摘要:

CONFERENCE ANNOUNCEMENT 1995 FIRST MEDITERRANEAN BASIN CONFERENCE ON ANALYTICAL CHEMISTRY Cordoba Spain 5-10 November 1995 In order to promote collaboration among analytical scientists of the whole Mediterranean Basin the 1995 First Mediterranean Basin Conference on Analytical Chemistry will provide an adequate forum for reporting and thoroughly discussing the latest research results in basic and instrumental developments in Analytical Chemistry. Other aims of this Conference are - To promote new opportunities for young scientists in the Mediterranean Sea area (particularly for those in the Southern Bank) to attend international meetings in countries of the region to attend training workshops on new analytical techniques to attend short courses on new techniques and trends in Analytical Chemistry and to establish new links for research i d o r other countries of the region.- To stimulate the progress of Analytical Chemistry as a whole by solving analytical problems affecting the Mediterranean Area. The program has been designed to attract participants from industry universities and research centers. The program will comprise invited plenary and key-note lecturers contributed oral papers and posters distributed in several Symposia covering the following topics Education of Analytical Chemistry Environmental Analytical Chemistry Agriculture and Food Analysis Geoanalytical Chemistry and Benefitiation of Minerals Biomedical Analysis Archeometry and Art Objects Preservation Quality Assurance and Harmonization of Procedures. A few Short Courses Special Sessions on "hot" topics and an Exhibition of Instrumentation has also been arranged.Invited lecturers who have already confirmed their contribution include M. Valckrcel I.B. Brenner D. Barcelo S. Caroli A. Laachach. O.X.F. Donnard M. M. Water H. Muntau J. Albaiges B.Y. Meklati P. Quevauviller etc. CALL FOR PAPERS 'Titles of submitted oral or poster presentations are solicited with the preliminary registration card by 30 May 1995. Submission of final Conference Abstracts are requested not later than 30 June 1995. SOCIAL ACTIVITIES Varied social activities including a visit to Granada are being planned. FURTHER INFORMATION For further information and pre-registration forms please contact Prof. Alfred0 Sanz-Medel (Chairman) Department of Physical and Analytical Chemistry Faculty of Chemistry University of Oviedo C/ Julian Claveria s/n 3300GOviedo SPAIN Phone 3 4 - 8 - 5 103480 o 34-8-5 103474 FAX 3 4 - 8 - 5 1031257996 Winter Conference on Plasm a Spect roch e m is try Fort Lauderdale Florida Januaty 8 - 7 3 7 996 The 1996 Winter Conference on Plasma Spectrochemistry ninth in a series of biennial meetings sponsored by the ICP information Newsletter features developments in plasma spectrochemical analysis by inductively coupled plasma (ICP) dc plasma (DCP) microwave plasma (MIP) and glow discharge (GDL HCL) sources.The meeting will be held Monday January 8 through Saturday January 13 1996 at the Bonaventure World Conference Center in Fort Lauderdale Florida. Continuing education short courses at introductory and advanced levels will be offered Friday through Sunday January 5 - 7.Spectroscopic instrumentation and accessories will be shown during a three-day exhibition. Objectives and Program The continued growth in popularity of plasma sources for atomization and excitation in atomic spectroscopy and ionization in mass Spectrometry and the need to discuss recent developments of these discharges in spectrochemical analysis stimulated the organization of this meeting. The Conference will bring together international scientists experienced in applications instrumentation and theory in an informal setting to examine recent progress in the field. Approximately 500 participants from 25 countries are expected to attend. Approximately 300 papers describing applications fundamentals and instrumental developments with plasma sources are expected to be presented in lecture and poster sessions by more than 200 authors.Symposia organized and chaired by recognized experts will include the following topics 1) Sample introduction and transport phenomena 2) Flow injection spectrochemical analysis 3) Elemental speciation with plasma/chromatographic techniques 4) Plasma instrumentation including chemometrics expert systems on-line analysis software and remote-system automation 5) Sample preparation treatment and automation 6) Excitation mechanisms and plasma phenomena 7) Spectroscopic standards and reference materials 8) Plasma source mass spectrometry 9) Glow discharge atomic and mass spectrometry 10) Applications of stable isotope analyses and 1 1) Laser-assisted plasma spectrometry.Six plenary and 18 invited lectures will highlight advances in these areas. Afternoon poster sessions will feature applications automation and new instrumentation. Five panel discussions will address critical development areas in sample introduction instrumentation elemental speciation plasma source mass spectrometry and novel software and hardware directions. Plenary invited and submitted papers will be published in Fall 1996 after peer review as the official Conference proceedings. Schedule of Activities Preliminary Title and 50-Word Abstract Due for Contributed Papers Exhibitor Booth Reservation and Pre-Registration Deadline Conference Pre-Registration October 13 1995 Hotel Pre-Reservation October 13 1995 Late Pre-Registration Deadline December 8,1995 1996 Winter Conference Short Courses January 5 - 7,1996 1 996 Winter Conference on Plasma Spectrochemistry January 8 - 13,1996 July 3 1995 September 1 1 1995 Further Information For further information return this form to 1996 Winter Conference on Plasma Spectrachemistry %/CP Information Newsletter Department of Chemistry Lederle GRC Towers University of Massachusetts Box 34510 Amherst MA 01 0034510 USA. ATTN Dr. Ramon Barnes Conference Chairman Telephone (41 3) 545-2294 Telefax (41 3) 545-4490. % 0 Send further information. Cl I plan to attend accompanied by CI I plan to present a paper (D oral CI poster 0 computer poster). Title 1996 WINTER CONFERENCE ON PLASMA SPECTROCHEMISTRY Name Organization Address City Telephone Title State/Coun try Telefax Date ZIP/Postal Code EMAlL

ISSN:0267-9477    

DOI:10.1039/JA99510BP004

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

Journal of Analytical Atomic Spectrometry (Including Atomic Spectrometry Updates) JAAS Editorial Board* Chairman B. L. Sharp (Loughborough UK) J. M. Gordon (Cambridge UK) S. J. Haswell (Hull UK) S. J. Hill (Plymouth UK) R. C. Hutton (Winsford UK) D. Littlejohn (Glasgow UK) J. Marshall (Middlesbrougi9 UK) D. L. Miles (Keyworth UK) A. Sanz-Medel (Oviedo Spain) JAAS Advisory Board F. C. Adams (Antwerp Belgium) R. M. Barnes (Amherst MA USA) L. Bezur (Budapest Hungary) M. W. Blades (Vancouver Canada) R. F. Browner (Atlanta GA USA) S. Caroli (Rome Italy) A. J. Curtius (florianopolis Brazil) J. B. Dawson (Leeds UK) M. T. C. de Loos-Vollebregt (Delft The Netherlands) L. Ebdon (Plymouth UK) M. S. Epstein (Gaithersburg MD USA) Fang Zhao-lun (Shenyang China) W. Frech (UmeA Sweden) A.L. Gray (Egham UK) S. Greenfield (Loughborough UK) G. M. Hieftje (Bloornington IN USA) B. V. L'vov (St. Petwsburg Russia) R. K. Marcus (Clemson SC USA) J. M. Mermet (Villeurbanne France) T. Nakahara (Osaka Japan) Ni Zhe-ming (Beijing China) N. Omenetto (Ispra Italy) C. J. Park (Jaejon Korea) R. E. Sturgeon (Ottawa Canada) V. Sychra (Prague Czech Republic) R. Van Grieken (Antwerp Belgium) A. Walsh K. B. (Victoria Australia) B. Welz (Uberlingerr Germany) Atomic Spectrometry Updates Editorial Board Chairman *D. L. Miles (Keyworth UK) J. Armstrong (Edinburgh UK) J. R. Bacon (Aberdeen. UK) C. Barnard (Glasgow UK) R. M. Barnes (Amherst MA USA) S. Branch (High Wycombe UK) R. Bye (Oslo Norway) J. Carroll (Middlesbrough UK) M. R. Cave (Keyworth UK) S. Chenery (Keyworth.U K ) *J. M. Cook (Keyworth UK) *M. S. Cresser (Aberdeen UK) H. M. Crews (Norwich UK) J. S. Crighton (Sunbury-on-Thames UK) *J. B. Dawson (Leeds UK) J. R. Dean (Newcastle upon Tyne UK) *A. T. Ellis (Oxford UK) *E. H. Evans (Plymouth UK) J. Fazakas (Budapest Hungary) A. Fisher (Plymouth. UK) *J. M. Gordon (Cambridge UK) D. J. Halls (Glasgow. UK) *S. J. Hill (Plymouth UK) K. W. Jackson (Albany NY USA) R. Jowitt (Middlesbrough UK ) K. Kitagawa (Nagoya Japan) J. Kubova (Bratislava Slovak Republic) *J. Marshall (Middlesbrough UK) H. Matusiewicz (Poznan Poland) A. W. McMahon (Manchester UK) J. M. Mermet (Villeurbanne France) R. G. Michel (Storrs CT USA) T. Nakahara (Osaka Japan) Ni Zhe-ming (Beijing China) P. R. Poole (Hamilton New Zealand) P. J. Potts (Milton Keynes; UK) W.J. Price (Budleigh Salterton UK) C. J. Rademeyer (Pretoria South Africa) *M. H. Ramsey (London WK) P. G. Riby (Greenwich UK) A. Sanz-Medel (Oviedo Spain) *B. L. Sharp (Loughborough UK) I. L. Shuttler (Uberlingen Germany) S. T. Sparkes (Plymouth UK) R. Stephens (Halifax Canada) J. Stupar (Ljubljana Slovenia) R. E. Sturgeon (Ottawa Canada) *A. Taylor (Guildford UK) G. C. Turk (Gaithersburg MD USA) J. F. Tyson (Amherst MA USA) P. Watkins (London UK) B. Welz (Uberlingen Germany) J. Williams (Egham UK) J. B. Willis (Victoria Australia) *Members of the ASU Executive Committee ~ ~~~~ Editor JAAS Janice M. Gordon The Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 4WF UK. Telephone + 44 (0) 1223 420066. Fax + 44 (0) 1223 420247.E-mail RSC1 @RSC.ORG (Internet) Senior Assistant Editor Brenda Holliday Editorial Secretary Lesley Turney US Associate Editor JAAS Dr. J. M. Harnly US Department of Agriculture Beltsville Human Nutrition IResearch Center Beltsville MD 20705 USA. Telephone 301 -504-8569 Assistant Editor Ziva Whitelock Advertisements Advertisement Department The Royal Society of Chemistry Burlington House Piccadilly London W1 V OBN UK. Telephone + 44 (0) 171 -287 3091. Fax +44 (0) 171 -494 11 34. Information for Authors Full details of how to submit materials for publi- cation in JAAS are given in the Instructions to Authors in Issue 1. Separate copies are available on request. The Journal of Analytical Atomic Spectrometry (JAAS) is an international journal for the publi- cation of original research papers communi- cations and letters concerned with the development and analytical application of atomic spectrometric techniques.The journal is pub- lished twelve times a year including comprehen- sive reviews of specific topics of interest to practising atomic spectroscopists and incorpor- ates the literature reviews which were previously published in Annual Reports on Analytical Atomic Spectroscopy (ARAAS). Manuscripts intended for publication must describe original work related to atomic spectro- metric analysis. Papers on all aspects of the sub- ject will be accepted including fundamental studies novel instrument developments and prac- tical analytical applications. As well as AAS AES and AFS papers will be welcomed on atomic mass spectrometry X-ray fluorescence/emission spectrometry and secondary emission spec- trometry.Papers describing the measurement of molecular species where these relate to the characterization of sources normally used for the production of atoms or are concerned for example with indirect methods of analysis will also be acceptable for publication. Papers describing the development and applications of hybrid techniques (e.g. GC-coupled AAS and HPLC-ICP) will be particularly welcome. Manuscripts on other subjects of direct interest to atomic spectroscopists including sample prep- aration and dissolution and analyte pre-concen- tration procedures as well as the statistical interpretation and use of atomic spectrometric data will also be acceptable for publication. There is no page charge.The following types of papers will be considered. Full papers. describing original work. Communications which must be on an urgent matter and be of obvious scientific importance. Communications receive priority and are usually published within 2-3 months of receipt. They are intended for brief descriptions of work that has progressed to a stage at which it is likely to be valuable to workers faced with similar problems. Reviews which must be a critical evaluation of the existing state of knowledge on a particular facet of analytical spectrometry. Every paper (except Communications) will be submitted to at least two referees by whose advice the Editorial Board of JAAS will be guided as to its acceptance or rejection. Papers that are accepted must not be published elsewhere except by permission. Submission of a manuscript will be regarded as an undertaking that the same material is not being considered for publication by another journal.Manuscripts (three copies typed in double spacing) should be sent to Janice M. Gordon Editor JAAS or Dr. J. M. Harnly US Associate Editor JAAS. All queries relating to the presentation and sub- mission of papers and any correspondence regarding accepted papers and proofs should be directed to the Editor or US Editor (addresses as above). Members of the JAAS Editorial Board (who may be contacted directly or via the Editorial Office) would welcome comments suggestions and advice on general policy matters concerning JAAS. Fifty reprints are supplied free of charge. Journal of Analytical Atomic Spectrometry (JAAS) (ISSN 0267-9477) is published monthly by The Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 4WF UK.All orders accompanied with payment should be sent directly to The Royal Society of Chemistry Turpin Distribution Services Ltd. Blackhorse Road Letchworth Herts. SG6 1 HN UK Tel. +44 (0) 1462 672555; Telex 825372 Turpin G; Fax +44 (0) 1462 480947. Turpin Distribution Services Ltd. is wholly owned by The Royal Society of Chemistry. 1995 Annual subscription rate EEA €51 2.00 USA $941 50 Canada €538.00 (+ GST) Rest of World €538.100. Customers should make payments by cheque in sterling payable on a UK clearing bank or in US dollars payable on a US clearing bank. Air freight and mailing in the USA by Publications Expediting Inc.200 Meacham Avenue Elmont NY 11 003. USA Postmaster send address changes to Journal of Analytical Atomic Spectrometry (JAAS) Publications Expediting Inc. 200 Meacham Avenue Elmont NY 11 003. Postage paid at Jamaica NY 11 431. All other despatches outside the UK by Bulk Airmail within Europe Accelerated Surface Post outside Europe. PRINTED IN THE UK. @The Royal Society of Chemistry 1995. All rights reserved. No part of this publication may be reproduced stored in a retrieval system or transmitted in any form or by any means electronic mechanical photographic recording or otherwise without the prior permission of the publishers.Journal of Analytical Atomic Spectrometry (Including Atomic Spectrometry Updates) JAAS Editorial Board* Chairman B.L. Sharp (Loughborough UK) J. M. Gordon (Cambridge UK) S. J. Haswell (Hull UK) S. J. Hill (Plymouth UK) R. C. Hutton (Winsford UK) D. Littlejohn (Glasgow UK) J. Marshall (Middlesbrough UK) A. T. Ellis (Abingdon UK) A. Sanz-Medel (Oviedo Spain) JAAS Advisory Board F. C. Adams (Antwerp Belgium) R. M. Barnes (Amherst MA USA) L. Bezur (Budapest Hungary) M. W. Blades (Vancouver Canada) R. F. Browner (Atlanta GA USA) S. Caroli (Rome Italy) A. J. Curtius (Florianopolis Brazil) J. B. Dawson (Leeds UK) M. T. C. de Loos-Vollebregt (Delft The Nether L. Ebdon (Plymouth UK) M. S. Epstein (Gaithersburg MD USA) Fang Zhao-lun (Shenyang China) W. Frech (UmeA Sweden) A. L. Gray (Egham UK) S. Greenfield (Loughborough UK) G. M. Hieftje (Bloomington IN USA) B.V. L'vov (St. Petersburg Russia) R. K. Marcus (Clemson SC USA) J. M. Mermet (Villeurbanne France) T. Nakahara (Osaka Japan) Ni Zhe-ming (Beijiny China) N. Omenetto (lspra Italy) C. J. Park (Taejon Korea) R. E. Sturgeon (Ottawa Canada) V. Sychra (Prague Czech Republic) R. Van Grieken (Antwerp Belgium) A. Walsh K. B. (Victoria Australia) B. Welz (Uberlingen Germany) -lands) Atomic Spectrometry Updates Editorial Board Chairman *A. T. Ellis (Abingdon UK) J. Armstrong (Edinburgh UK) J. R. Bacon (Aberdeen UK) C. Barnard (Glasgow UK) R. M. Barnes (Amherst MA USA) S. Branch (High Wycombe UK) R. Bye (Oslo Norway) J. Carroll (Middlesbrough UK) M. R. Cave (Keyworth UK) S. Chenery (Keyworth UK) *J. M. Cook (Keyworth UK) *M. S. Cresser (Aberdeen UK) H. M. Crews (Norwich UK) J.S. Crighton (Sunbury-on-Thames UK *J. B. Dawson (Leeds UK) J. R. Dean (Newcastle upon Tyne UK) *E. H. Evans (Plymouth UK) J. Fazakas (Budapest Hungary) A. Fisher (Plymouth UK) *J. M. Gordon (Cambridge UK) D. J. Halls (Glasgow UK) *S. J. Hill (Plymouth UK) K. W. Jackson (Albany NY USA) R. Jowitt (Middlesbrough UK) K. Kitagawa (Nagoya Japan) J. Kubova (Bratislava Slovak Republic) *J. Marshall (Middlesbrough UK) H. Matusiewicz (Poznan Poland) A. W. McMahon (Manchester UK) J. M. Mermet (Villeurbanne France) R. G. Michel (Storrs CT USA) *D. L. Miles (Keyworth U K ) T. Nakahara (Osaka Japan) Ni Zhe-ming (Beijing China) P. R. Poole (Hamilton New Zealand) P. J. Potts (Milton Keynes UK) W. J. Price (Budleigh Salterton UK) C. J. Rademeyer (Pretoria South Africa) *M. H. Ramsey (London UK) P.G. Riby (Greenwich UK) A. Sanz-Medel (Oviedo Spain) *B. L. Sharp (Loughborough UK) 1. L. Shuttler (Uberlingen Germany) S. T. Sparkes (Plymouth UK) R. Stephens (Halifax Canada) J. Stupar (Ljubljana Slovenia) R. E. Sturgeon (Ottawa Canada) *A. Taylor (Guildford UK) G. C. Turk (Gaithersburg MD USA) J. F. Tyson (Amherst MA USA) P. Watkins (London UK) B. Welz (Uberlingen Germany) J. Williams (Egham UK) J. B. Willis (Victoria Australia) *Members of the ASU Executive Committee Editor JAAS Janice M. Gordon The Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 4WF UK. Telephone + 44 (0) 1223 420066. Fax +44 (0) 1223 420247. E-mail RSCl @RSC.ORG (Internet) Senior Assistant Editor Brenda Holliday Editorial Secretary Lesley Turney US Associate Editor JAAS Dr.J. M. Harnly US Department of Agriculture Beltsville Human Nutrition Research Center Beltsville MD 20705 USA. Telephone 301 -504-8569 Assistant Editor Ziva Whitelock Advertisements Advertisement Department The Royal Society of Chemistry Burlington House Piccadilly London W1 V OBN UK. Telephone + 44 (0) 171 -287 3091. Fax +44 (0) 171 -494 11 34. Information for Authors Full details of how to submit materials for publi- cation in JAAS are given in the Instructions to Authors in Issue 1. Separate copies are available on request. The Journal of Analytical Atomic Spectrometry (JAAS) is an international journal for the publi- cation of original research papers communi- cations and letters concerned with the development and analytical application of atomic spectrometric techniques.The journal is pub- lished twelve times a year including comprehen- sive reviews of specific topics of interest to practising atomic spectroscopists and incorpor- ates the literature reviews which were previously published in Annual Reports on Analytical Atomic Spectroscopy (ARMS). Manuscripts intended for publication must describe original work related to atomic spectro- metric analysis. Papers on all aspects of the sub- ject will be accepted including fundamental studies novel instrument developments and prac- tical analytical applications. As well as AAS AES and AFS papers will be welcomed on atomic mass spectrometry X-ray fluorescence/emission spectrometry and secondary emission spec- trometry. Papers describing the measurement of molecular species where these relate to the characterization of sources normally used for the production of atoms or are concerned for example with indirect methods of analysis will also be acceptable for publication.Papers describing the development and applications of hybrid techniques (e.g. GC-coupled AAS and HPLC-ICP) will be particularly welcome. Manuscripts on other subjects of direct interest to atomic spectroscopists including sample prep- aration and dissolution and analyte pre-concen- tration procedures as well as the statistical interpretation and use of atomic spectrometric data will also be acceptable for publication. There is no page charge. The following types of papers will be considered. Full papers describing original work.Communications which must be on an urgent matter and be of obvious scientific importance. Communications receive priority and are usually published within 2-3 months of receipt. They are intended for brief descriptions of work that has progressed to a stage at which it is likely to be valuable to workers faced with similar problems. Reviews which must be a critical evaluation of the existing state of knowledge on a particular facet of analytical spectrometry. Every paper (except Communications) will be submitted to at least two referees by whose advice the Editorial Board of JAAS will be guided as to its acceptance or rejection. Papers that are accepted must not be published elsewhere except by permission. Submission of a manuscript will be regarded as an undertaking that the same material is not being considered for publication by another journal.Manuscripts (three copies typed in double spacing) should be sent to Janice M. Gordon Editor JAAS or Dr. J. M. Harnly US Associate Editor JAAS. All queries relating to the presentation and sub- mission of papers and any correspondence regarding accepted papers and proofs should be directed to the Editor or US Editor (addresses as above). .Members of the JAAS Editorial Board (who may be contacted directly or via the Editorial Office) would welcome comments suggestions and advice on general policy matters concerning JAAS. Fifty reprints are supplied free of charge. Journal of Analytical Atomic Spectrometry (JAAS) (ISSN 0267-9477) is published monthly by The Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 4WF UK.All orders accompanied with payment should be sent directly to The Royal Society of Chemistry Turpin Distribution Services Ltd. Blackhorse Road Letchworth Herts. SG6 1 HN UK Tel. + 44 (0) 1462 672555; Telex 825372 Turpin G; Fax +44 (0) 1462 480947. Turpin Distribution Services Ltd. is wholly owned by The Royal Society of Chemistry. 1995 Annual subscription rate EEA f512.00 USA $941.50 Canada f538.00 (+ GST) Rest of World f538.00. Customers should make payments by cheque in sterling payable on a UK clearing bank or in US dollars payable on a US clearing bank. Air freight and mailing in the USA by Publications Expediting Inc. 200 Meacham Avenue Elmont NY 11 003. USA Postmaster send address changes to Journal of Analytical Atomic Spectrometry (JAAS) Publications Expediting Inc. 200 Meacham Avenue Elmont NY 11003. Postage paid at Jamaica NY 11431. All other despatches outside the UK by Bulk Airmail within Europe Accelerated Surface Post outside Europe. PRINTED IN THE UK. @The Royal Society of Chemistry 1995. All rights reserved. No part of this publication may be reproduced stored in a retrieval system or transmitted in any form or by any means electronic mechanical photographic recording or otherwise without the prior permission of the publishers.

ISSN:0267-9477    

DOI:10.1039/JA99510FX013

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

Journal of C I1 Analytical I I 111111 1111 I I11111 I111 I CONTENTS NEWS PAGES Diary of Conferences and Courses Future Issues 27N 28N PAPERS Laser Ablation Sampling with Inductively Coupled Plasma Atomic Emission Spectrometry for the Analysis of Prototypical Glasses R. E. Russo X. L. Mao W. T. Chan M. F. Bryant W. F. Kinard Determination of Trace Elements in Food Contact Polymers by Semi- quantitative Inductively Coupled Plasma Mass Spectrometry. Performance Evaluation Using Alternative Multi-element Techniques and In-house Polymer Reference Materials Peter J. Fordham John W. Gramshaw Laurence Castle Helen M. Crews Diana Thompson Susan J. Parry Ed McCurdy Continuous Hydride Generation Low-pressure Microwave-induced Plasma Atomic Emission Spectrometry for the Determination of Arsenic Antimony and Selenium Florian Lunzer Rosario Pereiro-garcia Nerea Bordel-garcia Alfredo Sanz-medel Improved Thallium Hydride Generation Using Continuous Flow Methodologies Les Ebdon Phillip Goodall Steve J.Hill Peter Stockwell K. Clive Thompson Glucose as a Chemical Modifier for the Determination of Antimony and Selenium by Electrothermal Atomic Absorption Spectrometry M. Teresa Perez- Corona M. Beatriz De La Calle-Guntiiias Yolanda Madrid Carmen Camara Electrothermal Atomic Absorption Spectrometric Determination of Ultratrace Amounts of Tellurium Using a Palladium-coated L’vov Platform After Separation and Concentration by Hydride Generation and Liquid Anion Exchange Marco Grotti Ambrogio Mazzucotelli Determination of Barium by Electrothermal Atomic Absorption Spectrometry Maria In& C.Monteiro Adilson Jose Curtius Studies of Jet Configurations for Jet-enhanced Sputtering Devices Hyo J. Kim Yang S. Park Jung H. Cho Gae H. Lee Kyu H. Cho Kee B. Lee Ha S. Kim CUMULATIVE AUTHOR INDEX 295 303 31 1 31 7 321 325 329 335 341 AT0 M I C S P ECTRO M ET RY U P DAT ES Clinical and Biological materials Food and Beverages-Andrew Taylor Simon Branch Helen M. Crews David J. Halls Mark White References 105R 61 R 0 2 6 7 - 9 4 7 7 ( 1 9 9 5 1 1 . 1 - # Typeset printed and bound by The Charlesworth Group Huddersfield England 01 484 51 7077Yhat JAASbase is ... AASbase i s a unique database of atomic pectrometry reference information containing full )i bl iographic references to journal articles and :onference papers in the field of atomic pectrometry published since 1985.These eferences are selected by expert atomic ,pectroscopists who add supplementary nformation that allows you to search for the [.eferences you require. The backfile (covering 1985 to 1994) contains over 28,000 references. Update disks add around another 4,000 references a year. JAASbase has been designed to work with the database manager Idealist a fully indexed free-text ret r i eva I system. How will JAASbase help you? If you are an analytical scientist with a need for rapid access to information on techniques used in atomic spectrometry JAASbase i s the tool you need. Particularly if you work in an applications laboratory with a restricted budget for primary journals and little or no access to library facilities - JAASbase gives you instant access at your bench.Whether your area of analysis is food the env i r on men t q u a I i ty con tr o I g eol ogy met a I I u r gy or whatever JAASbase will quickly become an essential part of your working life. I 1 with the I . 1995 Subscription Price JAASbase Backfile (1 986-94) f 280.00/$490.00 JAASbase Updates 1995 f 99.00/$174.00 Idea I i st Software f 21 0.00/$368.00 Plus VAT in the UK Available in disk size 3.5'' or 5.25" I I I To order please contact The Royal Society of Chemistry Turpin Distribution Services Limited Blackhorse Road Letchworth Herts SG6 1 HN United Kingdom. Telephone +44 (0) 1462 672555. Fax +44 (0) 1462 480947. Turpin Distribution Services Limited is wholly owned by The Royal Society of Chemistry. RSC members' should order from The Royal Society of Chemistry Membership Administration Thomas Graham House Science Park Milton Road Cambridge CB4 4WF United Kingdom. TpIPohnne +44 (0) 1223 420066. Fax +44 (0) 1223 423623. E-Mail (Internet) RSC1 @RSC.ORG. THE ROYAL SOCIETY OF C H EM I STRY Information Services I

ISSN:0267-9477    

DOI:10.1039/JA99510BX015

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

DIARY OF CONFERENCES AND COURSE 1995 Fourth International Conference on Progress in Analytical Chemistry in the Steel and Metals Industry May 16-18 Jean Monnet Building Luxembourg Details can be found in J. Anal. At. Spectrom. 1994 9 50N. For details of providing a contribution to the programme or other information contact CEC/CETAS Conference R. Jowitt British Steel plc Technical Teesside Laboratories PO Box 11 Grangetown Middlesbrough Cleveland TS6 6UB. Telephone + 44 642 467144; Fax +44 642 460321. 43rd ASMS Conference on Mass Spectrometry and Allied Topics May 21-25 Atlanta GA USA For further details contact ASMS 1201 Don Diego Avenue Santa Fe NM 87501 USA. Telephone 505 989 4517; Fax 505 989 1073. 5th Annual Flow Injection Atomic Spectroscopy Short Course June 6-8 Amherst Massachusetts USA Details can be found in J .Anal. At. Spectrom. 1994 9 68N. For further information contact Julian F Tyson Department of Chemistry Lederle GRC Tower University of Massachusetts Box 34510 Amherst MA 01003-4510 USA. Telephone (413) 545 0195; Fax (413) 545 4846. Short Course. High-Performance Liquid Chromatography July 3-7 Loughborough U K Details can be found in J . Anal. At. Spectrom. 1995 10 18N. For further details contact Mrs. S. J. Maddison Depart men t of Chemistry University of Technology Loughboro- ugh Leics. LEll 3TU. Telephone (01 509) 222575 222563; Fax (01 509) 233163. SAC 95 July 9-15 Hull UK Details can be found in J. Anal. At. Spectrom. 1995 10 13N. For further information contact The Secretary Analytical Division The Royal Society of Chemistry Burlington House Piccadilly London W 1 V OBN UK.Vth COMTOX Symposium on Toxicology and Clinical Chemistry of Metals July 10-13 University of British Columbia Vancouver British Columbia Canada Details can be found in J . Anal. At. Spectrom. 1994 9 26N. For further information contact F. William Sunderman Jr. MD Department of Laboratory Medicine University of Conneticut Medical School Room C-2050 263 Farmington CT 06030-2225 USA. Telephone 203-679-2328. 13th Australian Symposium on Analytical Chemistry. In conjunction with 4th Environment Chemistry Conference - Chemistry in Tropical and Temperate Environments July 9-14 Darwin Northern Territory Australia Details can be found in J. Anal. At. Spectrom. 1995 10 19N. For further information contact Dr.Brian Salter-Duke Secretary 13AC/4EC Organizing Committee RACI GPO Box 363 Darwin NT 0801 Australia. 41st International Conference on Analytical Sciences and Spectroscopy August 14-16 Windsor Ontario Canada Details can be found in J. Anal. At. Spectrom. 1995 10 23N. For more information contact Dr William E. Jones. Telephone ( 5 19) 253 4232 ext 2001; Fax (519) 973 7098. The Third Asian Conference on Analytical Sciences ASIANALYSIS I11 August 20-24 Seoul Korea Details can be found in J. Anal. At. Spectrom. 1995 10 18N. Journal of Analytical Atomic Spectrometry For further details contact Prof. Hasuck Kim (Secretariat) ASIANALYIS 111 Department of Chemistry College of Natural Sciences Seoul National University Seoul 15 1-742 Korea. Telephone + 82(2)880-6638; Fax + 82(2)889-1568; E-mail hausukim@KRSNUCC 1.BITNET Colloquium Spectroscopicum Internationale (CSI) XXIX August 27-September 1 Leipzig Germany Details can be found in J .Anal. At. Spectrom. 1993 8 50N. For further details contact Prof. Dr. H. Nickel Forschungszentrum Julich GmbH Institut fur Werkstoffe der Energietechnik/RWTH Aachen D- 52425. Telephone (02461) 61 55 65; Fax (02461) 61 36 99. Colloquium Spectroscopicum Internationale (CSI) XXIX Post Symposium ICP-MS September 1-4 WernigerodelHartz Germany Details can be found in J . Anal. At. Spectrom. 1994 9 46N. For further details contact Dr. L. Moenke Martin-Luther University Halle- Wittenberg Department of Chemistry Institute of Analytical and Environmental Chemistry Weinbergurg 16 D-06120 Halle Germany.Fax 0049-345-649065. Euroanalysis IX September 1-7 Bologna Italy Details can be found in J . Anal. At. Spectrom. 1995 10 14N. Further information is available from Professor Luigia Sabbatini Euroanalysis IX Dipartimento di Chimica Universita di Bari Via Orabona 4 70126 Bari Italy. 8th International Conference on Coal Science September 10- 15 Znstituto Nacional del Carbbn CSIC Apartado 73 33080 Oviedo Spain Details can be found in J . Anal. At. Spectrom. 1994 9 62N. Journal of Analytical Atomic Spectrometry April 1995 VoZ. 10 27 NFor further details contact Dr. Juan M. D. Tascon 8th ICCS Scientific Programme Chairman Instituto Nacional del Carbon CSIC Apartado 73 33080 Oviedo Spain. Telephone + 34.8.528.08.00; Fax + 34.8.529.76.62. Sixth Surrey Conference on Plasma Source Spectrometry September 17-20 Jersey U K Details can be found in J.Anal. At. Spectrom. 1995 10 19N. For further details contact Dr. K. Jarvis NERC ICP-MS Facility Centre for Analytical Res. in the Environment (CARE) Imperial College at Silwood Park Buckhurst Road Ascot Berkshire SL5 7TE UK. Telephone +44(0) 344 294517; Fax +44(0) 344 873997. European Workshop in Chemometrics September 17-22 Bristol U K Details can be found in J. Anal. At. Spectrom. 1995 10 24N. For further details contact Mrs. C. Hutcheon School of Chemistry University of Bristol Contock’s Close Bristol BS8 lTS UK. Telephone + 44( 0) 1 17-928 7645 ext. 4221; Fax + 44-( 0) 1 17-925 1295. Federation of Analytical Chemistry and Spectroscopy Societies Conference October 15-20 Cincinnati Ohio USA Details can be found in J.Anal. At. Spectrom. 1995 10 19N. For further information contact Joseph A. Caruso FACSS National Office 198 Thomas Johnson Dr. Suite S-2 Frederick MD 21702 USA. Telephone ( 30 1 ) 694-8 122; Fax ( 30 1 ) 694-6860. First Mediterranean Basin Conference on Analytical Chemistry November 5-10 Cbrdoba Spain For further details contact Prof. Alfred0 Sanz-Medel Department of Physical and Analytical Chemistry Faculty of Chemistry. University of Oviedo C/ Julian Claveria no 8. 3006 Oviedo (Spain). Telephone 34/85/ 103474-103485; Fax 34/85/103480. Biological Applications of Inorganic Mass Spectrometry November 8-9 Norwich U K Details can be found in J . Anal. At. Spectrom. 1995 10 20N. For further information contact Dr. Fred Mellon Institute of Food Research Norwich Laboratory Norwich Research Park Colney Norwich NR4 7UA UK.Telephone +44(0)1603 255 299 (direct line) +44 (0) 1603 255 OOO (switchboard/paging); Fax +44 (0)1603 452578 +44 (0)1603 fred.mellon@BBSRC. AC.UK. 507723; E-MAIL International Symposium on Environmental Biomonitoring and Specimen Banking December 17-22 Honolulu Hawaii USA Details can be found in J . Anal. At. Spectrom. 1994 9 59N. For further information contact K. S. Subramanian Environmental Health Directorate Health Canada Tunney’s Pasture Ottawa Ontario K1A OL2 Canada (phone 613-957-1874; fax 613-941-4545) or G. V. Iyengar Center for Analytical Chemistry Room 235 B 125 National Institute of Standards and Technology Gaithersburg MD 20899 USA (Telephone 301-975-6284; Fax 301-921-9847) or M.Morita Division of Chemistry and Physics National Institute for Environmental Studies Japan Environmental Agency Yatabe-Machi Tsukuba Ibaraki 305 Japan (Telephone 81-298-51-61 11 ext. 260; Fax 81-298-56-4678). 1996 1996 Winter Conference on Plasma Spectrochemistry January 8-13 Fort Lauderdale Florida USA Details can be found in J . Anal. At. Spectrom. 1994,9,53N. For further information contact Dr. R. Barnes ICP Information Newsletter Department of Chemistry Lederle GRC Towers University of Massachusetts Box 345 10 Amherst MA 01003-45 10 USA. Telephone (41 3) 545 2294; Telefax (4 13) 545 4490. International Schools and Conferences on X-Ray Analytical Methods January 18-25 Sydney Australia Details can be found in J. Anal. At. Spectrom. 1994,9,47N. For further information contact AXAA ’96 Secretariat GPO Box 128 Sydney NSW 2001 Australia. Telephone 61 2 262 2277; Fax 61 2 262 2323; Telex AA 17651 1 TRHOST. Analytica Conference 96 April 23-26 Munich Germany Details can be found in J. Anal. At. Spectrom. 1994,2,69N. For further information contact Messe Miinchen GmbH Messegelande D-80325 Miinchen Germany. Telephone +49 89 51 07-0; Telex 5 212 086 ameg d; Fax + 49 89 5 1 07- 177. Eighth Biennial National Atomic Spectroscopy Symposium July 17-19 University of East Angliu Norwich U K For further information contact Dr. S. J. Haswell School of Chemistry University of Hull Hull HU6 7RX UK. Telephone + 44 (0)482-465469; Fax +44 (0)482-466410. 28 N Journal of Analytical Atomic Spectrometry April 1995 Vol. 10

ISSN:0267-9477    

DOI:10.1039/JA995100027N

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

FUTURE ISSUES WILL INCLUDE- Validation of the analytical linearity and of the discrimination correction model exhibited by multiple collection inductively coupled plasma mass spectrometry by means of a set of synthetic uranium is0 tope mixtures - Philip D. P. Taylor Paul De Bievre Andrew J. Walder Speciation of Organotin Compounds Using Inductively Coupled Plasma Mass Spectrometry with Micellar Liquid Chromatography-J’oshinori Inoue Katsuhiko Kawabata Yoshihito Suzuki Effect of Particle Size in the Analysis of Botanical Samples by Slurry Sampling and Fluorination Electrothermal Vaporization Inductively Coupled Plasma Atomic Emission Spectrometry (ETV-ICP-AES)-Yongchao Qin Zucheng Jiang Yun’e Zeng Bin Hu Determination of Antimony in Urine by Solvent Extraction and Atomic Absorption Spectrometry and its Application to Biological Monitoring of Occupational Exposure - Monica M.Smith Mark A. White H. Kerr Wilson Investigation of Pyrolyzed Ascorbic Acid in Electrothermal Graphite Furnace by Inductively Coupled Argon 28 N Journal of Analytical Atomic Spectrometry April 1995 Vol. 10Plasma Mass Spectrometry and Raman Spectrometry-Shoji Imaj Yasuko Phosphide by Electrothermal Atomic Fornari Nishiyama Toshiyuki Tanaka Yasuhisa Hay ashi Determination of Tellurium in Indium Absorption Spectrometry and ul traviole t-visi ble spectrop ho tometry- M. Taddia Alessandra Bellini Roberto COPIES OF CITED ARTICLES The Royal Society of Chemistry Library can usually supply copies of cited articles. For further details contact The Library Royal Society of Chemistry Burlington House Piccadilly London W1V OBN UK.Tel +44 (0) 71-437 8565; fax +44 (0) 71-287 9798; Telecom Gold 84; BUR210; Electronic Mailbox (Internet) LIBRARY@RSC.ORG. If the material is not available from the Society’s Library the staff will be pleased to advise on its availability from other sources. Please note that copies are not available from the RSC at Thomas Graham House Cambridge. 6th Surrey Conference on Plasma Source Spectrometry St. Helier Jersey UK 17-20 September 1995 Invited Lecturers Dr N Walsh (Royal Holloway) Dr C Gregoire (Geological Survey Canada) Professor R Barnes (University of Massachusetts) and Dr A Gray (Imperial College) Call f o r Papers Social Programme Registration Further Details Papers ( o r a l and poster presentations) on topics associated with all aspects of plasma source mass spectrometry and on ICP-AES and ICP-MS studies in the Earth Sciences.Three copies of abstracts must be submitted before July 2 8 1995 An informal reception will take place on the Sunday and a conference dinner on Wednesday evening. An accompanying persons‘ package is available. The residential package covers all meals coffee tea accommodation in single rooms and registration fee. A reduced fee is available for all bona f i d e students Dr K p Jarvis NERC ICP-MS Facility CARE Silwood Park Ascot Berks UK SLS 7TE. Tel + 4 4 (0)1344 294517/6; Fax +44 (0)1344 873997 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 29 NRamon M. Barnes Editor Department of Chemistry LGRC Towers University of Massachusetts Amherst MA 01003-0035 Telephone (41 3) 545-2294 fax 545-4490 0 b j ect I ve The ICP INFORMATION NEWSLETTER is a monthly journal published by the Plasma Research Group at the University of Massachusetts and is devoted exdusively to the rapid and Impartial dissemination of news and literature Information re- lated to the development and applications of plasma sources for spectrochemical analysis.Background ICP stands for inductively coupled plasma discharge which during the past decade has become the leading spectrochemi- cal excitation source for atomic emission spectroscopy. ICP discharges also are applied commercially as an ion source for mass spectrometry and as an atom and ion cell in atomic fluo- rescence spectrometry. The popularity of this source and the need to collect in a single literature reference all of the pertinent data on ICP stimulated the publication of the ICP INFOR- MATION NEWSETTER in 1975.Other popular plasma sources i.e. microwave induced plasmas direct current plasmas and glow discharges also are induded in the scope of the ICP IN- FORMATION NEWSLETTER. Scope As the only authoritative monthly journal of its type the ICP lNFORMA TION NEWSLETTER is read in more than 40 coun- tries by scientists actively applying or planning to use the ICP or other types of plasma spectroscopy. For the novice in the field the tCP INFORMATION NEWSLETTER provides a mnase and systematic source of information and background material needed for the selection of instrumentation or the development of methodology.For the experienced scientist it offers a sin- gle-source reference to current developments and literature. Editorial The ICP INFORMATION NEWSLETTER is edited by Dr. Ramon M. Barnes Professor of Chemistry University of Mas- sachusetts at Amherst with the assistance of a 20-member Board of National Correspondents composed of leading plasma spectroscopists. The Board members from around the world report news viewpoints and developments. Or. Barnes has been conducting plasma research on ICP and other dis- charges since 1968. He also serves as chairman of the Winter Conference on Plasma Spectrochemistry sponsored by the ICP INFORMATION NEWSLETTER. Regular Features .Original submitted and invited research articles by ICP and *Complete bibliography of all major ICP publications.*Abstracts of all ICP papers presented at major US and inter- .First-hand accounts of world-wide ICP developments. .Special reports on dcp microwave glow discharge and other Calendar and advanced programs of plasma meetings. .Technical translations and reprints of critical foreign-lan- guage ICP papers. *Critical reviews of plasma-related books and software. Conference Activities The ICP INFORMATION N€WSL€TT€R has sponsored seven international meetings on developments in atomic plasma spectrochemical analysis since 1980 in San Juan Orlando San Diego St. Petersburg and Kailua-Kona. Meeting pro- ceedings have appeared as Developments in Atomic Plasma Spectrochemical Analysis (wiley) Plasma Spectrochemistry and Plasma Spectrochemistry 11-1V (Pergamon Press) as well as in special issues of Spectrochimica Acta Parts and Journal of Analytical Atomic Spectrometry. The 1994 Winter Confer- ence on Plasma Spectrochemistry will be held in San Diego California January 10 - 15 1994; its proceedings will be published by Fall 1994.Subscription Information Subscriptions are available for 12 issues on either an annual or volume basis. The first issue of each volume begins in June and the last issue is published in May. For example Volume 18 runsfrom June 1992 through May 1993. Backissues beginning with Volume 1 May 1975 also are available. To begin a subscription complete the form below and submit it with prepayment or purchase information. For additional informa- tion please call (41 3) 545-2294 fax (41 3) 545-4490 or contact the Editor.Credit cards accepted. plasma experts. national meetings. plasma progress. To order complete this section and send it to ICP Information Newsletter %Dr. Ramon M. Barnes Depart- ment of Chemistry Lederle GRC Towers University of Massachusetts Am hetst MA 01 003-0035 USA. Start a subscription for the following issue D Volume(s)- (June 19- - May 19- ) or CI 19 (January December). Enclosed 0 Prepayment 0 Check or money order OVlSA D Mastercard Account No. (All 13 or 16 digits) ) or Cl Send invoice. Date Card holder Name Expiration date Cardholder Signature . Amount Due $ Mail to NfAtTW Organization Address City S tate/Cou n try- ZI P/Postalcode Telephone Telex/f ax Note For each credit-card transaction a 4 % service charge wiiI be added reflecting ow bank charges. 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ISSN:0267-9477    

DOI:10.1039/JA995100028N

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

ATOMIC SPECTROMETRY UPDATE- CLINICAL AND BIOLOGICAL MATERIALS FOOD AND BEVERAGES Atomic Spectrometry Update ANDREW TAYLOR* Supra-Regional Assay Service Metals Reference Laboratory Robens Institute of Industrial and Environmental Health and Safety University of Surrey Guildford Surrey UK GU2 5XH SIMON BRANCH The Lord Rank Research Centre R.H.M. Research and Engineering Lincoln Road High Wycombe Buckinghamshire UK HP12 3QR HELEN M. CREWS Ministry of Agriculture Fisheries and Food CSL Food Science Laboratory Norwich Research Park Colney Lane Norwich UK NR4 7UQ DAVID J . HALLS Trace Element Unit Institute of Biochemistry Royal Injirmary Castle Street Glasgow UK G4 OSF MARK WHITE The Health and Safety Laboratory Health and Safety Executive Broad Lane ShefJield UK S3 7HQ SUMMARY OF CONTENTS 1.1.1. General Reviews 1.2. Sampling and Sample Preparation 1.3. Developments in Multi-element Analysis 1.3.1. 1.3.2. 1.3.3. X-ray fluorescence spectrometry 1.3.4. 1.4. 1.5. 1.6. Hair and Nail Analysis 1.7. Drugs and Pharmaceuticals 1.8. Progress for Individual Elements 1.8.1. Aluminium 1.8.2. Antimony 1.8.3. Arsenic 1.8.4. Beryllium 1.8.5. Bismuth 1.8.6. Boron 1.8.7. Cadmium 1.8.8. Calcium 1.8.9. Chromium 1.8.10. Cobalt 1.8.1 1. Copper 1.8.12. Germanium 1.8.13. Gold 1.8.14. Indium 1.8.15. Iodine 1.8.16. Iron 1.8.17. Lead 1.8.18. Lithium 1.8.19. Magnesium 1.8.20. Manganese 1.8.21. Mercury 1.8.22. Molybdenum 1.8.23. Nickel 1.8.24. Platinum 1.8.25. Rare earth elements 1.8.26. Selenium 1.8.27. Silicon Analysis of Clinical and Biological Materials Inductively coupled and direct current plasma atomic emission spectrometry Inductively coupled plasma mass spectrometry and other mass spectrometric techniques Other multi-element techniques and studies Developments in Single Element Techniques Reference Materials and Quality Assessment 1.8.28.1.8.29. 1.8.30. 1.8.3 1. 1.8.32. 1.8.33. 1.8.34. 1.8.35. 1.9. 2. 2.1. 2.1.1. 2.1.2. 2.1.3. 2.1.4. 2.2. 2.3. 2.4. 2.5. 2.6. 2.7. 2.8. 2.8.1. 2.8.2. 2.8.3. 2.8.4. 2.8.5. 2.8.6. 2.8.7. 2.8.8. 2.8.9. 2.9. 2.10. 2.11. Silver Sodium and potassium Strontium Tin Titanium Thallium Vanadium Zinc Conclusions Table 1. Summary of Analysis of Clinical and Biological Materials Analysis of Foods and Beverages Sampling and Sample Preparation Direct determination of analytes Preconcen tra tion Digestion Direct solids and slurry sampling Speciation Studies Developments in Methodology for Flame Atomic Absorption Spectrometry Developments in Methodology for Electrothermal Atomic Absorption Spectrometry Developments in Methodology for Plasma Atomic Emission Spectrometry Developments in Methodology for Inductively Coupled Plasma Mass Spectrometry Applications of X-Ray Fluorescence Spectrometry Progress for Individual Elements Antimony Arsenic Barium Chromium Iron Mercury Iodine Selenium Tin Single and Multi-element Analysis of Foods Characterization Studies Reference Materials and Collaborative Trials Table 2.Summary of Analyses of Foods and Beverages Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 61 RThe information included in this Atomic Spectrometry Update is taken from papers 94/615-94/3502 listed each month as Atomic Spectrometry Updated References in the Journal of Analytical Atomic Spectrometry.It forms the tenth of our reviews of developments in the field of Clinical and Biological Materials Foods and Beverages. In 1986 there was enormous interest in the biological effects associated with exposure to aluminium and a great number of papers featuring this element were included in both the clinical and foods section of the first Update. This interest was sustained for many years and it is only in the last two or three Updates that we have seen a reduced number of publications concerned with this metal. Selenium bas now emerged as the element which has captured the leading position but with less prominence than was formerly associated with aluminium.As a consequence of various developments a number of other metals have featured regularly in recent Updates. Many countries have introduced legislation aimed at protection of employees against excessive occupational exposure to toxic metals and methods for measurement of chromium cobalt nickel and other metals in biological samples have been developed. Increasing concern as to the effects of commercial preparation and storage treatments has also required investigations of all food types. The food laboratories have taken full advantage of multi- element analytical techniques but we have not seen evidence of the ‘retirement’ of AAS in the face of ICP-AES ICP-MS or other approaches. While the importance of speciation has been understood for many years it is only quite recently as our Updates have shown that analytical techniques have emerged to permit realistic studies.We are conscious of new developments that have yet to feature significantly among the published work. However it is probable that these new ideas will develop quickly and it is our aim to include such work as soon as possible. 1. ANALYSIS OF CLINICAL AND BIOLOGICAL MATERIALS David J. Halls Andrew Taylor and Mark White This review covers developments in the application of atomic spectrometric techniques to the analysis of clinical and biologi- cal materials that have appeared in the literature and at conferences in the year approximately ending August 1994. Continuing innovations have produced new possibilities in a number of areas and with the development of high-resolution ICP-MS the field seems poised for a move forward into measurement of even lower concentrations.Table 1 at the end of Section 1 summarizes published and conference papers produced within the review year giving details where possible of methods used. 1.1. General Reviews The development of the first clinicd application of AAS was described in a fascinating historical account by Willis (94/2245). Walsh who developed the first AA spectrometer asked his colleague Willis to develop a method for the determi- nation of Ca in serum as Perkin-Elmer had intimated that they would be interested in taking out a licence to manufacture if this determination was possible by AAS. This task proved so difficult and frustrating that at one point Willis allowed himself a diversion to see how easy it would be to determine Mg in serum.This proved relatively straight forward allowing Willis to return refreshed to solve the problem of Ca. Savory and Wills (94/2244) reviewed the role of trace metals as essential nutrients and toxins and discussed their determi- nation. Recent trends in analytical methodology for trace element research were reviewed by Iyengar et al. (94/2109). Developments in the application of ETAAS to occupational and environmental health over the decade 1983-1992 were covered in a comprehensive review by Tsalev (94/2946) with 170 references. According to Tsalev ‘essential components of progress in the 1980s were not only the hardware support and methodological improvements but also the philosophy organ- ization education training and quality assurance in ultratrace analysis’. Applications of plasmas in routine and research clinical and biological analysis were discussed by Sanz-Medel (94/2110).Lobinski and Adams (94/941) reviewed recent advances in speciation analysis by capillary GC-MIP-AES describing applications to environmental and biological samples. 1.2. Sampling and Sample Preparation Progress continues in the application of on-line digestion. As predicted in last year’s Update (J. Anal. At. Spectrom. 1994 9 87R) the main applications have been found in the digestion of fluid samples such as whole blood or serum. The ultimate application of FI technology must be that of Burguera et al. (94/2248) in which blood was pumped directly from a patient’s forearm mixed with anticoagulant EDTA and an HN0,-HCl mixture digested in a microwave oven and part of the digested mixture injected into a carrier stream feeding an AA spec- trometer for the determination of Cu and Zn.Standards containing human albumin and glycerol were necessary to obtain accurate results. Guo and Baasner (94/3142) used microwave heating to oxidize blood with Br0,- and Br- under acid conditions for the determination of Hg by CVAAS in an FI system. Further oxidation by mixing with 0.05% m/v KMnO was carried out prior to reduction of Hg” to Hg with 0.05% m/v NaBH,. For determination of Se in serum by HG-ICP-AES Recknagel et al. (94/1645) digested samples on-line with an H2S0,-HC104-HN03 mixture which was passed through a reaction coil heated to 240°C and placed in an ultrasonic field to aid dispersion.Following reduction with NaBH the gas-liquid mixture was passed directly into the nebulizer of the ICP spectrometer. The spray chamber acted as a gas-liquid separator. On-line procedures .for preconcentration continue to be of interest. Schramel et al. (94/736) obtained enhancement factors of 6.4-13.5 for the determination of 11 elements by ICP-AES by preconcentrating the elements on an on-line 8-hydroxy- quinoline-cellulose microcolumn prior to eluting them directly into the nebulizer of the ICP spectrometer. To pre- concentrate Cd and Cu in digested plant and animal RMs and in urine Xu et al. (94/727) used a reversed-phase bonded silica as a sorbent in an FI system to collect chelates formed with diethylammonium diethyldithiocarbamate. The complexes were eluted with methanol into the nebulizer of a flame AA spectrometer.Overall enhancements of 126- and 114-fold resulting in LODs of 0.15 and 0.20 pg I-’ were obtained for Cd and Cu respectively. Results on RMs were generally satisfactory except for the determination of Cd in the presence of high concentrations of copper and/or iron. In a later version of this work Xu et al. (94/C3408) sorbed the complexes of Cd formed with NaDDC directly onto the walls of a knotted reactor and eluted with IBMK. The enhancement factor was 66 giving an LOD of 0.1 pg 1-’. Interferences from Cu and Fe were overcome by addition of thiourea and ascorbic acid- phenanthroline respectively. Tackling the same problem de Pefia et al.(94/3106) preconcentrated Cd as a dithizone complex on an activated carbon microcolumn and eluted with 150 p1 of IBMK. The activated carbon column provided more favourable results than a reversed-phase silica sorbent allowing preconcentration factors of up to 130 for a sample volume of 12 ml. Results obtained on digested biological tissue RMs were within the certified range. Cadmium in urine was determined 62R Journal of Analytical Atomic Spectrometry April 1995 Vol. 10by Dong and Fang (94/3156) using FAAS after collecting the Cd on an ion-exchange column and then eluting with 2 moll-' HCl. For 3.5 ml of sample an enhancement factor of 30 was obtained with an LOD of 0.3 pg 1-'. The use of the yeast Saccharomyces cereuisiae for preconcentrating trace elements was investigated by Maquieira et al.(94/2878). The yeast was immobilized on controlled pore glass and packed in a microcolumn. At pH 6-7.5 Cd Cu Fe Pb and Zn bound to the column and were eluted by lowering the pH to <2.0. Using determination by FAAS LODs of 0.2 0.7 0.6 8.0 and 0.1 pg 1-' were obtained for Cd Cu Fe Pb and Zn respectively. Similar procedures are also suitable for the on-line removal of interferences especially for ICP-MS. Ebdon et al. (94/2973) eliminated isobaric interferences from C1-containing species in the determination of As Cr Se and V in biological matrices by retaining the analytes as anions at pH 9 on an activated alumina microcolumn in an on-line FI system. Potassium persulfate was added in the digestion procedure to convert the elements into oxyanions and the SO4- produced as a result displaced C1- from the column.To breakdown As present as arsenobetaine samples were irradiated with UV light for 8 h in the presence of H202. For Se a 100-fold preconcentration step was necessary to obtain sufficient sensitivity. The pro- cedures were validated by the use of CRMs. The same kind of procedures have been used for preconcen- tration or matrix removal without on-line preparation. Soylak et al. (94/1665) used chelation with APDC to preconcentrate Cd Co Cu Fe Ni and Pb from dialysis fluids. The chelates were retained on an Amberlite XAD-4 column and then eluted with 1 mol I-' HNO in acetone. The eluate was evaporated to dryness and redissolved in aqueous 1 mol 1-' HNO for determination by ETAAS or FAAS.To remove interferences from Na and Cl in the determination of the 70Zn:68Zn ratio by ICP-MS Durrant et al. (94/2908) chelated the Zn on a column containing carboxymethylated poly(ethy1eneimine)- poly(methylenepolypheny1ene) isocyanate. Elution was with 2 mol 1-' HNO,. The method applied to digested human urine and bovine milk was simpler .than previous extraction procedures. Interesting applications of surfactant-based ordered media in analytical atomic spectrometry were discussed by Sanz-Medel et al. (94/3036). Reactions at the molecular level become more efficient leading for example to an increase of up to two-fold in sensitivity in the determination of As and Pb by HG-ICP- AES. A volatile Cd species could also be formed by reaction with NaBH in an ordered medium.Applications of micellar or vesicular mobile phases in HPLC was also possible enabling for example the separation of toxic forms of As coupled with the on-line generation of ASH with the enhance- ment described above. The suitability of an open-focused microwaue heating system for the digestion of clinical samples for determination of trace elements by ICP-AES was examined by Krushevska et al. (94/2556). Digestion with HN03-H,S04-H202 gave low residual carbon content even when the volume of H2S04 was reduced to avoid nebulizer effects in ICP-AES. Low recoveries for Pb and Sr could be avoided by adding 15% HNO or 12% HC1-3% HNO to the final solution. All insoluble sulfate formation including that of Ba could be avoided by adding 1.2% m/v of the ammonium salt of EDTA.Open vessels were also used by Chakraborti et al. (94/3016) for digestion of biological and environmental samples for determination of Cd Cu Fe Mn and Pb by ETAAS. Their technique allowed the preparation of up to 100 samples in one operation. Preparation times for biological materials comparable to those taken by microwave pressure digestion can be achieved by partial digestion with HNO at 105 "C (94/1618 94/C3427). Niazi et al. (94/1618) showed that the elements Cu Fe Mn and Zn were completely released from tissue samples after heating for 20 min. Centrifugation of the samples after digestion improved the separation from undigested fat. Results on CRMs were in good agreement with certified values and results on a bovine liver sample were in agreement with those obtained after a recommended H202-H,S0 digestion procedure. Measurements were by FAAS ICP-AES and ETAAS.For determination of Cd and Pb in marine biological tissue by ETAAS Tinggi et al. (94/686) compared wet digestion by HN0,-H,SO HN0,-H202 and HN0,-HClO,. The last was considered most efficient. In the first SO4- depressed the absorbance especially for the determination of Pb. Adeljou et al. (94/3130) found that to obtain complete breakdown of organic mercury digestion with mixtures of HNO3-H2SO or HN0,-H202 was necessary. Nitric acid alone or HN0,-HClO gave low recoveries. They preferred HN0,-H2S04 as this gave the most accurate and reproducible data on a range of biological and environmental CRMs.By contrast Tahan et al. (94/2187) found that recovery was complete with pressure digestion in Parr bombs using HN0,-HClO with either microwave or convection heating. The method was shown to be satisfactory for whole blood lyophilized tissue and pond sediment samples. The work of DUlivo et al. on the use of HBr-Br2 digestion in the determination of Se has been published (94/742). Quantitative recovery of Se from organoselenium compounds such as selenomethionine selenocysteine and selenopurine could be obtained in 90 min at 122 "C using 0.01 mol 1-' Br in 48% HBr. The method was applied to the determination of Se in human urine and serum by HG-AFS. Slurry sampling for ETAAS has been developed further by Miller-Ihli (94/732) who discussed an optimized general approach for preparation of slurries involving grinding biologi- cal and botanical samples with PTFE beads and maintaining slurries with ultrasonic agitation.Slurry sampling for MIP- AES was investigated by Matusiewicz and Sturgeon (94/1010). Using a V-groove Babington nebulizer satisfactory results were obtained with a 1% m/v slurry of Lobster Hepatopancreas RM in 10% v/v HNO,. 1.3. Developments in Multi-element Analysis 1.3.1. Inductively coupled and direct current plasma atomic emission spectrometry With the aim of producing a direct method for the determi- nation of trace elements in human milk by ICP-AES Carrion et al. (94/2909) emulsified the milk samples with ethoxynonyl- phenol to 0.03% m/v. Samples were then diluted ten-fold to a final HNO concentration of 1 YO v/v.Standards prepared with identical acid and surfactant concentrations gave good recov- ery. The method applied to the determination of Ca Cu Fe Mg P and Zn in maternal milk gave results with a precision of 0.3-2.0% RSD. No problems with nebulizer blockage were found. Violante et al. (94/1106) concluded that of all the lines they studied for the determination of aluminium in serum by ICP- AES the only suitable line of sufficient sensitivity was that at 396.15 nm but this was overlapped by the 396.83 nm Ca line. Burden et al. (94/C3441) came to the same conclusion but found that for optimum accuracy precision and sensitivity the instrumental conditions and sample diluent were critical. Under optimum conditions measurement of A1 in clinical samples down to 1 pg 1-' was possible.The optimum conditions for the determination of B in biological tissues by ICP-AES were evaluated by Pullmann et al. (94/1635). The lowest LOD (25 pg 1 - I ) was obtained at the 249.6 nm line with a Babington nebulizer and with a forward power of 1.3 kW. Samples were digested with HNO Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 63Runder elevated temperature and pressure for 2 h in PTFE bombs. The method could be used for the determination of natural concentrations of B in tissues (0.1-0.3 pg g-') as well as for measurement after uptake of B compounds in boron neutron capture therapy (1-5 pg g-'). Concentrations of Mn and Sr in serum were determined by ICP-AES after three-fold dilution with 1 mol 1-' HNO by Ma et al. (94/1075). Calibration was by standard additions.Dysprosium conccntrations in monkey serum resulting from the administration of a contrast medium for magnetic reson- ance imaging were measured at the 353.17nm line by ICP- AES (94/3164). Samples were diluted 100-fold with 1 mol 1-' HCl. The LOD was 24 pg I-'. Selenium concentrations in serum were measured by an on-line procedure involving wet ashing with H,S0,-HC104-HN03 at 240 "C generation of H,Se with NaBH and introduction of the gas-liquid mixture into the nebulizer of an ICP-AE spectrometer. The spray chamber acted as a gas-liquid separator. Measurement of the Se concentration of a Seronorm serum CRM and comparison of results on samples with those obtained by ETAAS confirmed the accuracy of the procedure. There are various ways of improving the sensitivity of ICP- AES.Uchida et al. (94/3133) used ultrasonic nebulization to determine Cd Co Cu Ni and Pb in digests of a range of plant and biological RMs. On-line preconcentration on an 8-hydroxyquinoline cellulose column enabled Schramel et al. (94/736) to obtain signal enhancements of 6.4- 13.5-fold for peak height and 3.7-5.8-fold for peak area in measurement of 11 elements by simultaneous ICP-AES. The technique was applied to the determination of Cr Cu Fe Mn Ni V and Zn in a number of CRMs. Results were satisfactory except for Cr and Fe. Electrothermal vaporization can also provide a gain in sensitivity but as in ETAAS measurement of the refractory elements is difficult. Zucheng (94/C3372) showed that a PTFE slurry acted as a fluorinating agent improving the LODs of the refractory elements by 1-2 orders of magnitude compared with conventional ETV-ICP-AES.The technique was applied to the determination of B Cr Mo REEs and V in slurried biological RMs. Introduction of slurries into a microwave-induced plasma AE spectrometer was shown to be possible by Matusiewicz and Sturgeon (94/1010). A Babington nebulizer introduced 1 % slurries of Lobster Hepatopancreas RM in 10% v/v HNO into the MIP. To obtain accurate results for Cd Cu Fe and Zn in the RM standard additions calibration was necessary. 1.3.2. inductively coupled plasma mass spectrometry and other mass spectrometric techniques Two reviews on applications of ICP-MS in the clinical field have appeared. Barnes (94/2540) reviewed applications to human nutrition and toxicology illustrating with examples of measurement of isotopes for studies of Zn nutrition and Pb toxicity.Morita's review in Japanese (94/1353) covers examples of hair analysis by ICP-MS laser ablation and speciation by Comparison with other techniques has highlighted the advan- tages of ZCP-MS. Hess (94/3191) found that both AAS and ICP-MS gave accurate and precise results for the determination of As Cd Co Cu Mn Pb T1 and Zn in urine but the analysis of the 8 elements took only 6 min by ICP-MS compared with 32min by AAS. For measuring skin absorption of Pb Dale et al. (97/2795) compared TIMS and ICP-MS for the measure- ment of low levels of Pb in body fluids. Whilst TIMS showed better accuracy and precision ICP-MS was favoured because of the minimal sample preparation and high sample throughput.Spectral interferences remain a significant drawback in the application of ICP-MS to clinical and biological analysis HPLC-ICP-MS. particularly for As and Se. Polyatomic ions originating from the elements C Ca C1 K Na P and S in biological matrices have been studied by Vanhoe et al. (94/2905). For several analytes factors were calculated to quantitate the extent of interference. Ways of correcting for interferences were reviewed. Goosens et al. (94/1294) found that interferences in the determi- nation of As and Se could be overcome if 4% C,H,OH was added to solutions and the nebulizer gas flow adjusted. Under these conditions accurate results were obtained with standard additions calibration on serum and urine CRMs.Cryogenic desolvation was used by Alvez et al. (94/1281) to reduce polyatomic interferences in the determination of As Ni and V in seawater and urine CRMs. Addition of a small amount of H (2%) to the aerosol gas flow enhanced signals by a factor of 2-3 compensating for the loss of sensitivity caused by desolvation. Samples were diluted with 1% HNO so that chlorine could be removed as HCl. Results on the CRMs were in agreement with the certified values. Other possibilities for removal of interferences are on-line techniques using retention of analytes on a column of activated alumina (94/2973) or chelating resin (94/2908) and subsequent elution or for those who enjoy added complexity separation by ASV. Pretty et al. (94/2879) determined Cr"' and Vv without polyatomic inter- ference by depositing on a working electrode and subsequent stripping for determination by ICP-MS.Recoveries were not however quantitative (62% and 43% for Cr and V respectively). The determination of a range of elements in human serum was described by Vanhoe et al. (94/2213). Using five-fold dilution of sample with 0.14 mol 1-' HNO and suitable internal standards they were able to measure B Ba Bi Cd Cs Hg Li Mo Pb Sn and Sb in the Versieck second- generation serum RM. Normal ranges were also established for these elements. For determination of Bi Cd and Sb the sensitivity was barely adequate. Further details of their work on B (94/2536) and Bi (94/2615) are given in separate publi- cations. The latter also gives results of measurements in serum of patients and volunteers who had taken therapeutic doses of colloidal bismuth subcitrate.About 1.5 to 2 h after intake Bi concentrations had increased by several orders of magnitude above normal values. When therapy was stopped Bi concen- trations slowly returned to normal over a period of months. Mauras et al. (94/2614) developed a method for the determi- nation of Bi Pb and TI in plasma and urine by ICP-MS. In 23 healthy individuals Bi and T1 concentrations were below the quantification limits (1.2 and 2.5 nmol l-' respectively) but the mean Pb concentration in plasma was 8.2nmol 1-' higher than the range reported by Vanhoe et al. (94/2213) of 0.5-3.5 nmol 1-'. In work on the determination of I Vanhoe et al. (94/2554) found that the oxidation state of the analyte had a strong influence on the analytical performance.When I was present as I- and HNO was used for acidification the ion signal was not stable and falsely high recoveries of up to 750% were obtained. If NH solution was used as diluent instead of HNO recoveries were reasonable and results were satisfactory for the second-generation serum RM for sera from healthy individuals and for Milk Powder CRMs. As Trentini et al. (94/610) found A1 concentrations in the sera of patients on haemodialysis can be measured satisfactorily by ICP-MS giving results which are in good agreement with those obtained by ETAAS. The determination of Cd and Pb in whole blood by ICP-MS was demonstrated by Stroh (94/2345). Samples were diluted 1 +9 with 0.2% NH solution and 0.1% Triton X-100.The accuracy and precision was better with isotope dilution than with an external calibration method. Cadmium Cu and Pb in urine were determined by Lu et al. (94/2811) using ICP-MS with isotope dilution and FI sample introduction. The LODs were 25,45 and 58 ng 1- ' for Cd Cu 64R Journal of' Analytical Atomic Spectrometry April 1995 Vol. 10and Pb respectively. Results obtained for NIST SRM Toxic Metals in Urine agreed well with the certificate values. The use of a new high-resolution ICP mass spectrometer for solving some of the spectral interferences found in the analysis of trace elements in serum was explored by Moens et ul. (94/3277). The instrument offered resolution settings of 300 3000 and 7000 (MIAM 10% valley definition). In a second generation human serum RM diluted 4-8-fold Cu Fe V and Zn were determined with good accuracy at a resolution of 3000 free of polyatomic interference.The low resolution mode offered high sensitivity limited by the ability to achieve low enough blanks. Helium as a plasma gas offers advantages of more efficient ionization and reduced spectral interferences. Fecher and Nagengast (94/3269) studied the determination of As Br I and Se in biological samples with a prototype He MIP mass spectrometer. Pneumatic nebulization with a Meinhard nebul- izer was used without desolvation. Unexpectedly sensitivities were 1.6-5.5-fold worse than with an Ar ICP but the back- ground was lower so that the resultant LODs were comparable. Measurement of As and Se in a range of food animal tissue and plant CRMs gave accurate results except when the Ca and C1 concentrations were very high.Results for Br and I were close to the certified values. The application of laser ablation ICP-MS to the determi- nation of envirionmental contaminants such as Cd and Pb in calcified materials from fish and aquatic mammals was demon- strated by Evans et al. (94/3263). For example the outermost layer of walrus teeth the cementum is developed as a series of annual layers and by measuring the changes in concen- tration across these layers it was hoped that a picture could be built up of the changes in contamination with time. Within each layer there was some variation in concentration which required sampling of a large number of spots ( ~ 1 0 0 ) . This was achieved by developing a computer programme and hardware modifications to carry this out automatically.Optimization of laser pulse rate and pulse time was important to achieve ablation holes free of scorching and fracturing. Signals were expressed as a ratio to that of an internal standard 44Ca to account for variation in ablation. Speciation studies continue to form a significant proportion of applications of ICP-MS. For a study of Pt species in a new anti-tumour drug formulation Cairns et al. (94/C3495) devel- oped a novel HPLC-ICP-MS interface based on thermospray nebulization. The eluate was desolvated with a membrane drier tube and a cryogenic condenser cooled by the Peltier effect. The Pt species were separated on a reversed-phase column with a mobile phase of acetonitrile-H,O.Methods suitable for the study of metabolites of cis-platin were devel- oped by Zhao et al. (94/1407) using reversed-phase ion-pairing LC with sodium dodecylsulfate or heptanesulfonate as the ion- pairing reagents. Conditions were established for the separation of cis-platin hydrolysis products and for the products of reaction of cis-platin with methionine cysteine and glutathione. The distribution of Au in red cells from patients treated with Au-based drugs was studied by Zhang et ul. (94/C1905) using HPLC-ICP-MS. Gold in the red cell lysate was found to be bound not to haemoglobin but to a higher molecular mass species (M z 300,000). The extent of uptake of Au seemed to vary greatly from patient to patient. The trace elements Cu Fe and Zn were speciated in a gut model by Dundar et al.(94/C3484) using reversed-phase HPLC with detection by ICP-MS Speciation of Cr"' and Cr"' Ni" and V" and Vv was carried out by Tomlinson et al. (94/3258) using a mixed anion-cation exchange HPLC column and elution with a solution of the lithium salt of 2,6-pyridinedicarboxylic acid. Conditions were established under which interconversion of the species did not occur. Application to the NIST SRM 2670 Toxic Metals in Urine gave successful resolution of the two forms of V and a single peak for Ni with accurate quantitation. For Cr however disturbances of the baseline and polyatomic interference prevented a result from being obtained. Sulfhydryl groups were determined in chicken ovalbumin after conversion to mercury mercaptides which were separated by HPLC and the Hg detected by ICP-MS (94/2533).Of five reagents evalu- ated ethylmercuric chloride was found to give the fastest conversion. Kumar et al. (94/2689) separated organotins in fish by reversed-phase HPLC with ICP-MS detection. Inorganic Sn was found to bind strongly on the columns used. The LODs were 1.6 1.5 and 2.3 pg for trimethyltin tributyltin and triphenlytin respectively. The use of stable isotopes for absorption and bioavailability studies using MS was discussed in detail by Mellon et a!. (94/2543). Examples of applications to the study of Ca and Zn absorption were described. Turnlund et al. (94/2183) deter- mined isotope ratios for Ca in samples enriched with 44Ca by automated multiple-collector TIMS. The method developed was applied to the analysis of urine and ashed faecal samples in a study of Ca absorption and excretion in very low birthweight infants fed on human or formula milk.The Ca was separated from the samples by precipitation as the oxalate followed by dissolution of the washed precipitate in HN03. Measurement of the 44Ca 46Ca and 48Ca isotopes was made simultaneously giving isotope ratios with a between-batch precision of 0.07% RSD for urine and 0.09% RSD for faecal samples. Techniques for the isolation of Fe from biological samples to remove isobaric interferences in the measurement of Fe isotope ratios by FAB-MS were described by Flory (94/2532). Precisions of d 1.2% RSD were achieved. Absorption and retention of Mo in adults has been studied by Soltani-Neshan and co-workers (94/2650,94/3 192).The stable isotope 'OOMo was administered orally and the ratio 98Mo lwMo measured in faecal and urine samples by ICP-MS with a precision of 0.1-1.0% RSD. In the seven adults studied 35-96% Mo was absorbed and 0.5-46% retained. For three of them most of the Mo was found in the faeces whereas for the others it was mainly in the urine. Veillon et nl. (94/3184) described a method for measurement of Cr isotope ratios in urine by ID-GC-MS using chelation with trifluoroacetylace- tone. The method could also be used for total Cr measurement down to an LOD of 0.03 ng g-' and was accurate in the determination of Cr in CRMs and in comparison of results with independent methods. The same basic method was applied to the determination of blood volume with an enriched stable isotope 53Cr (94/3200) and was a reliable and safer alternative to existing methods using radioactive 'lCr.The isotope ratios determined in sheep's blood and tissues by ETV-ICP-MS by Gregoire and Lee (94/2944) after preconcentration to obtain sufficient sensitivity. Plasma red cells liver and kidney were digested with HN03 using microwave heating and the Cd and Zn separated from matrix components on a column of 8-hydroxyquinoline immobilized on silica. The eluate was taken to dryness and reconstituted in a minimal volume of 1% v/v HNOJ (0.2 ml) to give a preconcentration factor of 35-fold thus achieving LODs of 0.34 and 0.40 pg g-' for Cd and Zn in blood respectively. Peak height measurement gave poorer precision than peak area which enabled determination of the ratios to 2-3% RSD for Cd and 1% for Zn.For removal of spectral interferences Durrant et al. (94/2908) separated Zn from matrix components on a chelating resin prior to determi- nation of the 70Zn 68Zn ratio by ICP-MS (see also section 1.2). The possibilities of ID-GC-MS continue to be demonstrated by Aggarwal et al. (94/769 94/1325). Using 19,Pt as internal standard Pt in urine ultrafiltrate and whole plasma were measured after use of lithium bis(trifluoroethy1)dithiocarba- mate as chelating agent and measurement of the volatile chelates by GC-MS (97/769). Comparison of results with 111Cd 106cd 111Cd. . lloCd 68Zn 67Zn and 68Zn 66Zn were Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 65Rthose by methods using ETAAS showed good agreement for urine but significant differences for ultrafiltrate and whole plasma.Application to the determination of Ni in semen and urine has also been described (94/1325). Resonance ionization mass spectrometry has been applied to the determination of Cr in urine (94/1006 94/1321 94/1393). The NIST Urine SRM was digested with HN03-H202 and portions air-dried on to tantalum ribbon filaments which were placed in the ionization region of a time of flight spectrometer. Atoms were ionized by a two-photon transition using energy from an excimer laser-pumped dye laser. Using ID a Cr concentration of 9 3 f 8 pg 1-' was obtained close to the certified value of 85+6 pg 1-'. Studies on the uptake of Cu by single cells have also been reported (94/1393).Time offright SIMS and its application to biological analysis was reviewed by Niehuis (94/1527). Application of SIMS to the determination of trace elements in nanolitre volumes of biological fluids was described by Chia et al. (94/1541). Results using linear calibration were accurate and precise provided that the aliquot was representative of the whole sample. The feasibility of using SIMS to image ion transport in cells was studied by Chandra and Morrison (94/1543). Barium Cs Li Mn and Sr were tested as possible tracers. The difficulties of quantitation in laser microprobe mass spectrometry were discussed by Love11 et al. (94/1416). Methods for biological tissues using LM MS allow simultaneous multie- lement determination at high sensitivity and with high spatial resolution (about 1 pm).The advantages and disadvantages of various methods of quantitation using internal or external standards were compared. They advocated for tissue analysis the use of standards for Al Ca and Fe based on their complexes with cis-dicyc1ohexano-18-crown-6-ether. 1.3.3. X-ray fluorescence spectrometry Sampling and sample preparation for EDXRF were discussed by Holynska (94/1565). Care is needed to obtain a representa- tive sample and to avoid contamination of the sample and loss of elements in preparation. Voglis et al. (94/1570) applied a recently developed capillary- focused XRF spectrometer to the element mapping of bone. Using L-line XRF Rosen et al. (94/2496) measured Pb concen- trations in bone of a US suburban population previously exposed to Pb emissions from a nearby factory.Concentrations were three-fold higher than in a similar population not exposed. Blood Pb concentrations were apparently uninformative about the extent of previous exposure. A similar conclusion was reached by Erkkila et al. (94/2306) in their study by XRF of Pb concentrations in active and retired workers at acid battery manufacturers. Bone Pb concentrations in the exposed popu- lation were distinctly separated from controls whereas blood Pb concentrations showed less of a distinction. Comparison was made between measurement at four skeletal sites. Heavy elements in archaelogical samples of tooth enamel and dentine were measured by PIXE in a study by Buoso et al. (94/2300). Calibration was made by using standards prepared by adding known amounts of the elements to hydroxyapatite.The long term stability of trace elements in total parenterul nutrition (TPN)fruids was studied by Allwood and Greenwood (94/23 10). Precipitating material was collected on a membrane filter and measured by EDXRF. The trace elements Cu Fe Rb Se and Zn were measured in serum by TRXRF in research by Dogan et al. (94/1728). Samples were digested with HN03 either at normal or elevated pressure. An aliquot (20 pl) was pipetted onto a sample carrier and the solvent evaporated. They found that patients with BehCet disease a multisystemic vasculitic disorder found in Turkey had significantly lower Rb Se and Zn concentrations in serum than those of controls. Development and applications of SRXRF are showing pro- gress.Iida and Noma (94/1599) built a microprobe with a beam size of around 5 pm which they used to study the distribution of trace elements in cross-sections of human hair. Mapping of trace elements in cartilage from calf scapula to a resolution of 10 pm was carried out by Vittur et al. (94/2307). In resting regions of the cartilage the elements appeared homogenously distributed but were altered in hypertropic- calcified tissue. The distribution of Zn appeared to match that of alkaline phosphatase a Zn-containing enzyme involved in calcification. Analysis of an Ox-Liver RM by SRXRF per- formed by An et al. (94/2569) showed concentrations com- parable to those obtained by other atomic spectrometric techniques. Measurement of elements at the cellular leuel is now possible.Yao et al. (94/2381) used micro-PIXE for elemental distribution analysis and SRXRF for quantitative elemental analysis of liver cells. Nuclear microscopy was applied by Lindh (94/905) to study the distribution of trace elements in cells while PIXE was used for quantitative analysis. The intracellular distri- bution of major and trace elements in blood cells was found to give useful clinical information in inflammatory connective tissue diseases and chronic fatigue syndrome. 1.3.4. Other multi-element techniques and studies Simultaneous multi-element determinations by E TAAS continue to be demonstrated. Workers from Hitachi (94/1705) showed that Al Cd Cr Mo and Ni concentrations in whole blood could be determined after four-fold dilution addition of Pd as modifier and using calibration with standard additions.For Mn and Se a modifier of Pd with ascorbic acid was more effective while for As Pd with potassium persulfate as oxidizing agent was necessary. Sneddon and Farah (94/C1947) applied their four-element system to a range of materials including blood and urine. Suitable modifiers were examined together with a comparison of Smith-Hieftje and continuum source background correction. Changes in 19 trace element concentrations in human brains with ageing studied by Saito et al. (94/1712) showed increases in Cd and Sn concentrations and decreases in K and Rb. Measurements were by FAES AAS and ICP-MS. Five regions of brain were studied revealing differences in distribution of the trace elements.Sixteen elements in bone biopsies from patients on dialysis were determined by Minoia et al. (94/1686) using ETAAS ICP-AES and NAA. Results were compared with reference values and discussed in relation to time on dialysis and type of treatment. The influence of alumina implants on the Al Ca and P concentrations in iliac bone of rabbits was examined by Wang et al. (94/824). Measurements by JCP-AES showed that the implant released A1 into the bone and lowered the Ca and P concentrations compared with control bones. Children aged 7-15 years with bone age delay living in high fluoride areas were studied by Qian et ul. (94/2173). The group with highest urinary F- concentrations as measured by an ISE had a higher risk of bone age delay than the group with the lowest F- concentration.In addition serum Ca Cu Mg and Zn concentrations were measured by AAS. Of these serum Cu concentrations seemed to be related to the susceptibility to bone age delay. Reference values for 22 elements in whole blood serum and urine measured by ETAAS HG-AAS and ICP-AES were reported by Sabbioni et al. (94/1681). Concentrations of 16 elements in lung tissue were determined by Alimonti et ul. (94/1105). Samples taken at autopsy were dry-ashed and the ash dissolved in HN03 for determination by ICP-AES and ETAAS. Reference values for Cu Cr Fe Mn and Se in human milk were determined by Salvato et al. (94/1679) using ETAAS 66R Journal of Analytical Atomic Spectrometry April 1995 V d . 10after simple dilution of samples with addition of a Mg(N03) or Ni modifier when necessary.Anderson (94/1867) studied the longitudinal changes in Ba Cu Fe Si Sr and Zn concen- trations in milk by ICP-AES during the first five months of lactation. Of these Cu Fe and Zn reduced significantly but changes in the others were not significant. Long term corrosion by salivu of Co-Cr Ni-Cr and Pd-based dental alloys and pure dental Ti was investigated by Strietzel et ul. (94/830) using measurements by AAS. Pure Ti and alloys containing more than 20% Cr showed the lowest corrosion. Research continues on the cellular concentrations of trace elements. Schmitt et ul. (94/1101) determined by ETAAS Cr Cu and Zn concentrations in whole blood plasma erythro- cytes platelets and leucocytes comparing samples from patients with non-Hodgkins lymphoma and controls.Cells were separ- ated by density gradient centrifugation. They concluded that the intracellular and extracellular behaviour of trace elements did not necessarily correlate. The effect of lithium treatment on concentrations of Ca and Mg in plasma and erythrocytes was studied by Linder et al. (94/1843) using AAS. Long term treatment led to increased intra- and extracellular Mg and increased extracellular and decreased intracellular Ca. The finding of low plasma Se reduced plasma Zn and increased plasma Cu concentrations is common to many disease states. It is seen in a study by Suzuki et al. (94/1701) on patients with gastrointestinal and hepatobiliary cancer. The lower than normal plasma Se concentrations were associated with tumour spread and inadequate diet or intravenous nutrition and correlated with other markers of nutritional status such as protein concentrations.Shinohara et al. (94/1703) found that in children with congenital biliary atresia concentrations of Se in red blood cells and plasma were both significantly different from controls. Concentrations of Cu Fe Mg and Zn were also measured. In the patient group red blood cell Fe and Mg and plasma Zn concentrations were lower than controls while plasma Cu was higher. Measurements were by AAS and fluorometry. In a study of essential and toxic elements in liver and kidney of muskoxen from Victoria Island Canada Salisbury et al. (94/1242) measured in acid digests of the tissues Cu Mn and Zn by FAAS As and Se by HGAAS Hg by CVAAS and Cd and Pb by ETAAS.Comparison was made with results obtained for domestic cattle and sheep. 1.4. Developments in Single Element Techniques Probe atomization very effectively removed interferences in the determination of Pb in urine by ETAAS in a method developed by Chen and Littlejohn (94/712). Samples were simply diluted 2-12.5-fold with 1 YO v/v HNO,. Accuracy was demonstrated by analysis of RMs and by comparison of results with those obtained by a method using extraction of Pb into IBMK with APDC prior to determination by ETAAS. However probe atomization was not found to be useful in the determination of Cr in serum and urine. In this study Cimadevilla et. ul. (94/2401) compared atomization from wall platform and probe. Wall atomization from a pyrolytic graphite coated graphite tube provided the best sensitivity and precision.Trapping techniques allow the determination of hydride- forming elements with excellent sensitivity. Ni et al. (94/2185) trapped Se and Te hydrides on a graphite tube coated with Ag a less expensive alternative to the more costly Pd trapping agent An additional advantage was that atomization occurred at a lower temperature ( 1800 "C) than with a Pd-coated surface (>2000°C) which increased the lifetime of the tube. The characteristic masses were 17 and 18 pg for Se and Te respectively. The platinum-loop atomizer inserted into an air-C2H2 flame was applied to the determination of Li by AES by Ozdemir . et ul. (94/3122). Interferences from Ca and Sr normally found in FAES were not present as the salts of these elements remained non-volatilized on the loop.An LOD of 0.34 pg 1 - I was achieved from a 100 pl aliquot of solution (equivalent to 0.007 ng Li) and application to the determination of Li in a range of samples including blood was demonstrated. Free fatty acids (94/1755) were determined indirectly by measuring Cu by FAAS after extracting the acids from organ- isms with CHC1,-C6Hl4-CH30H and adding Cu to form copper soaps. Comparison with results obtained by a colori- metric method showed good agreement. There have been some interesting applications of lasers. Heitmann et ul. (94/2951) applied LEAFS to the determination of As and Se in whole blood. A Nd:YAG pump laser was used with two synchronously pumped dye lasers to obtain the As and Se excitation lines at 193.7 and 196.0 nm respectively in the vacuum ultraviolet.Detection limits were 5.4 and 1.5 ng 1-' respectively. Selenium was determined in 300 blood samples by diluting samples 10-20-fold with 0.2% v/v HNOJ and 0.01% v/v Triton X-100; Pd was added as a modifier. Laser-enhanced ionization spectrometry was shown by Epier et al. (94/2394) to be a very sensitive detector for LC. The method was applied to the determination of organolead com- pounds in NIST SRM Oyster Tissue. Burakov et al. (94/2929) applied intracavity laser spectroscopy to the determination of I in urine using the molecular bands of Iz. The urine was placed in a quartz cell heated to 80-90°C. Prior to measure- ment a few drops of H2S04 and H202 were added to convert I - into 1,. Laser radiation at 580-590nm was absorbed by the I molecules in the vapour above the liquid.The LOD was 15 pg 1-'. Electrodeposition as a means of collecting the element prior to determination has featured in previous Updates. Zhang et al. (94/664) electrodeposited Cd from urine on to a tungsten wire cathode for 2 min. The wire was then placed in a graphite furnace for determination by ETAAS. The LOD was 0.01 pg1-l. Since the determination of Cd in urine is adequately carried out by direct procedures this approach seems of little value. 1.5. Reference Materials and Quality Assessment Roelandts (94/979) has produced an updated list of biological and environmental RMs. A computer program that allows integrated quality control method evaluation and proficiency testing was described by workers from the Danish National Institute of Occupational Health (94/650) The internal quality control uses Shewhart .and z-control charts.The proficiency testing part evaluates results from a group of laboratories and has been used for the assessment of the performance of 29 Danish laboratories in the determination of Pb in blood. From the same Institute comes a paper detailing the use of internal quality control in the determination of Cr in blood and serum by ETAAS with Zeeman-effect background correction (94/927). In the esti- mation of reference values for persons not occupationally exposed to Cr 45% of serum and 57% of blood results were below the LODs (0.17 and 0.27 pg 1-' respectively). A statisti- cal evaluation was used to estimate the reference interval.1.6. Hair and Nail Analysis The results of a five year international project supported by the IAEA on the relationship between concentrations of trace elements in hair and in internal organs has been published (94/676). The conclusions are so important that they are worth repeating. Cortes Tor0 et al. stated 'For the elements Zn and Cu there is no correlation when comparing trace element concentrations in hair with those in internal tissues. Arsenic and Hg concentrations seem to correlate to some extent with Journal of' Analytical Atomic Spectrometry April 1995 Vol. 10 67 Rthe levels of these elements in liver and kidney. Selenium is positively correlated with the concentration in liver kidney and spleen.' In this study protocols were laid down for col- lecting lung liver kidney brain bone and hair samples at autopsy for their preparation and for quality assurance. Determination was mainly by NAA XRF and PIXE.Circulation of unknown samples showed reasonable agreement for Cu Se and Zn but much poorer agreement for As Cd Hg and Pb. This led them to a further conclusion that the results of hair analysis would be of little value if their quality was not improved. They called on analysts to devote more effort to validate their analytical procedures to produce reliable and valuable results. By measuring the Hg and TI concentrations along the length of single strands of hair Yoshinaga et al. (94/1369) were able to reconstruct the recent exposure and uptake history of the subjects. Each hair section several mm long was dissolved in a volume of HNO (typically 50 pl) and then diluted.Aliquots (50pl) were introduced by an FI system into an ICP mass spectrometer. The examples shown were from a T1-poisoned patient and from a Russian scientist visiting Japan. The Hg concentrations at the distal end were low corresponding to his life in Russia where his fish consumption was minimal; whereas at the follicle end his hair Hg concentration was high reflecting his greater consumption of fish in Japan. Changes in concentration of Ca Cu Fe and Zn along the length of women's hair during pregnancy was followed by Wu et al. (94/1069) using SRXRF. Tsalev et al. (94/935) found measurements of trace element concentrations in toenails to be useful for biological monitor- ing. The nails after scraping clean and washing with 0.1% m/v Triton X-100 were solubilized with 40% v/v tetraethylam- monium hydroxide solution at 90 "C for 30 min.The elements Cu Fe and Zn were determined by pulse nebulization FAAS whereas Al As Co Mo Ni Sb Se and Sn were determined by ETAAS. Cadmium Cr Mn and Pb were determined by both techniques. Reference ranges from control groups were produced for all elements. Fingernails were analysed by Hayashi et al. (94/1205) for Cd Pb and Zn by dry-ashing dissolution in HNO and determination by AAS. Concentrations were found to vary with age sex season and dietary habits. For the determination of Se in hair and nails Harrison et al. (94/C3439) found the digestion procedure was critical. The final procedure developed involved digestion with HN03-H202 in a PTFE bomb with microwave heating a procedure which was shown to successfully oxidize selenome- thionine.Measurement of Se was then made by ETAAS with a Pd modifier. Total mercury in hair was determined by CVAAS with gold foil preconcentration by Bruhn et al. (94/2965). Digestion with HNO in a PTFE bomb for 1.5 h at 110°C was compared with digestion in a sealed pyrex ampoule for 24 h at 50°C. The latter was preferred as it was simpler less expensive and more suited to the simultaneous treatment of a number of samples. Between-batch variation in the determination was 4.8% RSD at a Hg concentration of 1.1Opg g-I. Determination of methylmercury in hair was achieved by Kratzer et ul. (94/2928) using selective leaching with HCl and determination by CVAAS.The conditions of leaching were established by radiotracer studies. Comparison with an alterna- tive solvent extraction procedure showed good agreement. Residual inorganic Hg was determined after leaching by wash- ing and drying the hair and then combusting the hair in a stream of O2 and collecting the Hg on a gold collector for determination by CVAAS. Studies by Pineau et al. (94/832) on the determination by ETAAS of A / in hair of patients on long term dialysis led them to the conclusion that hair concentrations were of no value as an indicator of A1 accumulation in the body. Detailed methods for individual elements or groups of elements in hair have been developed by Chinese workers. Considering the simplicity of dissolving hair in acid it would seem that some of the digestion procedures used are unnecessarily com- plicated. Procedures for determination include FAAS after metal chelate co-precipitation for Cd (94/1058) and Mn (94/2143); Ni (94/1842) and Sr (94/1073) by FAAS; Co by ETAAS (94/1096); Ca Cu Fe Mg Mn and Zn by pulse nebulization FAAS (94/1214); and 14 elements by vertical electrode AES (94/836).The elements As Sb Se and Te were determined in hair and nails by Nakaaki et ul. (94/1700) using HGAAS following digestion with HN03-H202-HC1. For 93 non-occupationally exposed persons the geometric mean hair concentrations were 18.3 ng g-' As 8.2 ng g-' Sb and 349 ng g-' Se; normal Te concentrations were not measurable. 1.7. Drugs and Pharmaceuticals The number of papers describing applications of atomic spec- trometry in the analysis of pharmaceutical preparations has increased in this review year.Many of the papers describe the determination of toxic elements in traditional Chinese patent medicines often herbal in origin. Most of the abstracts seen by the reviewer give details of the methodology but not of the results. However Zhuo et al. (94/C3404) reported Hg concen- trations greater than 0.5 mg kg-' for the medicines that they analysed by CVAAS and Takano et al. (94/2134) found average concentrations of 15 g kg-' Hg and 4.1 g kg-' As in 'Bezoar antifebrile pills'. Their investigations by XRF AAS colorimetry and XRD led them to the conclusion that each pill (3 g) contained 30-60 mg cinnabar (HgS) and 10-40 mg realgar (ASS). Methodologies in other studies were CVAAS for Hg (94/2626 94/280 1 ) ICP-AES for multi-element determinations (94/960 94/1168) and ETAAS with a Pd-Mg(NO,) modifier for As and Pb determination (94/2172) with a Ni modifier for As (94/2801) and a PO4 modifier for Pb (94/2801).Speciation of trace elements was studied by Fan et al. (94/2624) using ETAAS HPLC ion-exchange chromatography spectrophoto- metry fluorimetry and catalytic polarography. Bayly et al. (94/C3117) reported five cases of Pb poisoning in the West Midlands UK resulting from the taking of imported traditional remedies. In one case the source of poisoning was confirmed by measurement of the Pb isotope ratios in the medicine and in the patient's blood. With the aim of reducing the sample preparation time in the determination of B in pharmaceutical preparations by ICP- AES Bearman and Donaghy (94/C3463) avoided acid decomposition and evaluated direct dissolution in organic solvents.Acetic acid was the preferred solvent because of its favourable washout time and its low organic band structure at the 249.77 nm B line. Isegawa et al. (94/1710) determined Cr Mo and Se in nutrient solutions used for TPN. Chromium and Mn were determined by ETAAS and Se by HGAAS. Natural concen- trations were found to be insufficient to provide the daily nutritional requirement of these elements. Trace element concentrations in diaspirin cross-linked hae- moglobin solutions were determined by Marshall et al. (94/815) using ICP-AES. Only Ca Fe Mg and Zn were present in measurable concentrations. To determine non-haem iron this was complexed with diethylenetriaminepentaacetic acid and the sample subjected to ultracentrifugation. The Fe in the ultrafiltrate was then measured by ICP-AES.Concentrations of 30 minor and trace elements in Nigerian cigarettes and raw tobacco were determined by Oladipo et al. 68R Journul of Anulyticul Atomic Spectrometry April 1995 Vol. 10(94/1409) using ICP-MS. The NIST SRM Citrus Leaves was analysed to establish the accuracy of the procedure. A number of indirect procedures have been described for the measurement of active pharmaceutical ingredients. Glycine was determined in an FI system by passing the sample solution through a reactor containing copper carbonate immobilized in a polyester resin (94/697). The glycine complexed the Cu thus releasing it for determination by FAAS.The LOD was 1.2 mg I-' and at 20mg 1-' the precision was 1.1% RSD. Samples could be analysed at a rate of 180 h-I. The alkaloids papaverine strychnine and cocaine were determined by Eisman et al. (94/2204) by injecting the reagent BiI,- into a carrier stream containing the alkaloid in solution. The precipi- tated ion pair of the alkaloid with Bi14- was collected on a filter and the Bi concentration in the carrier measured on-line by FAAS. The concentration of alkaloid was proportional to the decrease in the absorbance of the Bi. The method was used to determine papaverine in commercial preparations. In their procedure Ye and Wang (94/C3410) determined alkaloids by reacting with Cr(NH,),(SCN),- to form an insoluble ion pair which was separated by solvent flotation. The decrease in Cr concentration measured by AES was proportional to the alkaloid concentration.The antihistamines terfenadine and chlorphenoxamine hydrochloride were reacted with Co and SCN- to form a ternary complex extractable into benzene (94/772). This could be measured by spectrophotometry at 625 nm or the Co could be measured by AAS. Results by both methods on the analysis of pharmaceutical preparations gave results in agreement with those by official methods. 1.8. Progress for Individual Elements 1.8.1. Aluminium Methods for the determination of A1 in biological fluids continue to be developed for clinical monitoring of long term renal dialysis patients. The effectiveness of different chemical modifiers for the quantitative determination of A1 in serum was examined by Betinelli et al.(94/1683). With Zeeman-effect background correction and STPF conditions K2Cr207 was found to give better analytical sensitivity than Mg(N03),. The former chemical modifier was subsequently used to determine reference values for serum A1 in an Italian population. In the ETAAS method described by Johnson and Treble (94/674) for the determination of A1 in body fluids STPF conditions chemical modification with Mg( and standard additions calibration were necessary for accurate quantitation. In con- trast Bandinelli (94/1208) simply diluted samples 1 + 3 with 0.1% Triton X-100 for quantitative analysis of A1 in serum from long term renal dialysis patients. The same method was applied to the determination of A1 in tap water from the dialysis centres. Violante et al.(94/1106) investigated the use of alternative spectral lines for the determination of A1 in serum by ICP-AES. To overcome overlap interferences from Ca on the measurement of A1 at 396.15 nm measurements were made at 237.35 nm. However measurement at this alternative line was only accurate for high A1 concentrations. The authors concluded that measurement at 396.15 nm was essential for determination of A1 at the low levels found in the general population. The relationship between A1 and Si in serum dialysis patients was examined by Wrobel et al. (94/2924) using ETAAS to determine both elements. Aluminium and Si species associated with low and high M serum fractions were separated by ultramicrofiltration.A fraction of Al amounting to 11% of the total serum Al was ultrafiltrable and was not influenced by total serum element levels or renal pathology. Administration of desferrioxamine a1 tered the speciation of A1 by increasing the relative proportion of A1 in the low M fraction to 75% of the serum total. Distribution of A1 between low and high M fractions was not related to Si distribution in serum. The biological significance of plasma and hair A1 levels in long term renal dialysis patients was examined by Pineau et al. (94/832) using Zeeman-effect ETAAS. Plasma A1 levels showed a positive correlation with length of dialysis treatment but no relationship between plasma and hair A1 levels was observed. The authors concluded that hair A1 measurements were of no value as indicators of A1 body burden.Several groups have investigated the distribution of A1 in brain and other body tissues in an effort to clarify the link between A1 and neuropathological conditions. Radunovic et al. (94/711) determined A1 in rat tissues by ETAAS with in situ O2 ashing following HNO digestion. Standard additions calibration with a NH,H,PO chemical modifier was necessary for accurate quantitation of A1 in bone tissues. Aluminium concentrations were ten-fold higher in bone than other tissues. Cerebellar levels of A1 (0.073 pg g-I) were twice those in the cerebral hemispheres. Levels of A1 in autopsy brain samples from Alzheimer's disease patients were determined by Xu et al. (94/891). The ETAAS method used K2Cr207 as a chemical modifier to overcome interferences from high levels of P and alkali metals.The highest level of A1 determined in the brain tissues was 8 pg g-'. The authors identified small but signifi- cant increases in A1 levels in specific regions of Alzheimer's disease brain (hippocampus superior and middle temporal gyri) compared with neurologically normal controls. The intra- cellular distribution of A1 and other trace elements in brain tissue was examined by Lukiw et al. (94/1657). Twenty trace elements in nucleosomes generated by mononuclease digestion of brain cell nuclei were determined by ETAAS and ICP-AES. A 4.5-9-fold increase in nuclear A1 levels was found in Alzheimer's disease-affected nuclei from cells of the superior temporal gyrus. The authors concluded like the previous group that brain A1 is localized to specific cell populations within specific regions of the brain.1.8.2. Antimony Radiotracer studies were undertaken by Dahl et al. (94/2209) to evaluate the effectiveness of noble metals as chemical modifiers for the direct determination of Sb in biological fluids by ETAAS. The most effective modifier was a mixture of Pd Pt Rh and Ru all at concentrations of 0.025%. The noble metal cocktail was combined. with 1% ascorbic acid in the atomizer to ensure that the modifiers remained in their metal form during the early steps of the temperature programme. The modifier gave quantitative recovery of Sb for ashing temperatures up to 1200°C. A simpler Ni chemical modifier was described by Chen et al. (94/844) in an ETAAS method for the determination of Sb in human urine.The method gave recoveries of between 97 and 102% and had an LOD of 6.7 pg 1-'. 1.8.3. Arsenic Speciation studies have again dominated the work on this element during the review period. The speciation of As by HPLC using micellar and vesicular mobile phases was com- prehensively reviewed by Sanz-Medel et al. (94/3036). An HGAAS method for As in urine capable of discriminating dietary and occupational sources of As exposure was reported by Le et al. (94/663). To quantitate the four As species As"' AsV dimethylarsinic acid and monomethylarsonic acid urine was treated with L-cysteine and introduced into the HG system for generation of ASH,. Total As in a second aliquot of the same urine sample was determined by generation of ASH following microwave digestion with K,S,08-NaOH to convert all As (including arsenobetaine) to AsV.Hanna et al. (94/1729) described a method for the quantitative determination of inorganic As"' and AsV and the organic metabolites dimethyl- Journal of Anulytical Atomic Spectrometry April 1995 Vol. 10 69Rarsinic acid and monomethylarsonic acid in urine by FI-HGAAS. Non-toxic arsenobetaine and arsenocholine were separated from the sample by solid-phase extraction. The extracted sample was digested with HN03-H2S04-K2Cr207 and treated with H202. All As" was reduced to As"' with KI in HCl and the sample introduced into the FI system. Limits of detection for As in the injected solution were 0.1-0.2 pg 1-'. Methods for the determination of organoarsenic species in biological fluids have usually been applied to urine analysis.Fisher et al. (94/C3477) however used an HPLC-ICP-MS technique to determine organoarsenic species in plasma of haemodialysis patients. Chromatographic separation was achieved with aqueous NH3-K2S04 on an ion-exchange column. Arsenobetaine was the only organoarsenic species detected in plasma and did not accumulate in patients with impaired renal function. A modified electrically heated quartz tube furnace was developed by Mayer et al. (94/637) for the determination of total As and Se in biological samples by HGAAS. The heating block was open ended to allow easy interchange of fused silica tubes. Optimum sensitivity for As was achieved at a tube temperature of 1100 "C. Microwave digestion and conventional wet digestion methods for sample pre-treatment were also compared.Total urinary As levels in patients with Blackfoot disease were also determined by HGAAS in a study by Pan et al. (94/877). Urine samples were microwave digested with HNO and preconcentrated on a solid-phase extraction car- tridge for analysis of As by HGAAS and Hg by CVAAS. Mean levels of As in urine from Blackfoot disease patients were 33.6 pg 1-' compared with 11.3 pg 1-' in controls. Procedures for eliminating polyatomic interferences in the determination of As in biological samples by ICP-MS have continued to appear. Goossens et al. (94/1294) overcame the interference effects of 40Ar40Ar+ 40Ar35Cl + and 32s1603+ in the determination of As and Se through a combination of chemical modification with ethanol and adjustment of nebul- izer gas conditions.Standard additions calibration enabled accurate determination of both elements in urine and serum CRMs. Ebdon and colleagues (94/2973) eliminated many of the polyatomic interferences in the determination of As (and Cr Se and V) by separation of the analytes from the biological matrix using an activated alumina micro-column. The column was connected to the FI-ICP-MS system to enable simul- taneous on-line matrix elimination and preconcentration. Recoveries of the elements from marine biological CRMs were near 100% and the LOD for As was 9 pg I-'. 1.8.4. Beryllium A method for the direct determination of Be in urine by ETAAS with Zeeman eflect background correction was devel- oped by Minoia et al. (94/800) in which an Mg(N0,)2 chemical modifier was used to increase the thermal stability of the analyte.The method gave a detection limit of 0.03 pg I-' and precision of 10.8% at the 1.7 pg 1-' level. 1.8.5. Bismuth Eisman et al. (94/2204) adopted a new approach to the indirect determination of the alkaloids papaverine strychnine and cocaine by coupling FI to FAAS detection. The alkaloids were precipitated with BiI,- complexing agent and removed by on-line filtration. The concentration of alkaloid was pro- portional to the decrease in the Bi absorbance signal of the complexing agent measured by FAAS. The authors reported significantly improved repeatability with this method com- pared with extraction methods. The new method could deter- mine alkaloid concentrations up to 1OOpg 1-' with a repeatability better than 2.5% and a sampling frequency of 100 h-'.Inductively coupled plasma-MS was used by Vanhoe et al. (94/2615) to establish reference values for Bi in human serum and to determine serum Bi concentrations in subjects taking therapeutic doses of colloidal bismuth subcitrate (CBS). Dilution with 0.14 mol 1-' HN03 was the only sample pre- treatment necessary for accurate quantitation of Bi. Reference values for serum Bi in healthy adults ranged from <0.007 to 0.067 pg 1-' whilst serum levels in subjects taking CBS were 50-1500 times greater. After stopping CBS treatment serum Bi levels returned to normal after several months. Slikkerveer et al. (94/1047) determined Bi in biological tissues by ETAAS following a wet digestion sample pre-treatment.The method employed Pt as a chemical modifier to stabilize Bi in the graphite tube and a gas stop step at atomization to enhance signal sensitivity. Bismuth concentrations were measured in the tissues of rats administered CBS. Bismuth was detected in liver kidney and spleen but not in bone or brain. 1.8.6. Boron There have been further reports of sensitive methods for the determination of B in biological fluids and tissues in relation to monitoring for boron neutron capture therapy. Papaspyrou et al. (94/3026) developed a simple ETAAS method for the direct determination of B in cell suspensions. A modified autosampler and furnace with an argon bypass system and magnetic stirrer enabled precise and repeatable analysis of samples of cell suspensions injected directly into a pyrolytically coated graphite tube.Optimum conditions for the determi- nation of trace levels of B in biological tissues by ICP-AES were investigated by Pollmann et al. (94/1635). Tissue samples were digested with HNO in a PTFE bomb. The lowest detection limit (25 pg 1-') was achieved using a Babington type nebulizer with a gas flow of 1 1 min-'. and Ar as the outer gas. Two groups described simple sample pretreatment procedures for the determination of B in serum and plasma using an ICP source. Vanhoe et al. (94/2536) diluted serum five-fold with 0.14 mol 1-' HNO and added Be as an internal standard for ICP-MS determination of B. Memory effects were minimized by using a short clean-out procedure after each sample. A detection limit of 0.5 pg I-' was reported.Ferrando et al. (94/813) used microwave digestion with ultrapure double distilled HNO to determine B in plasma by ICP-AES. To determine the suitability of different B carriers for neutron capture therapy Gregoire et al. (94/2114) determined B in mouse tissues and plasma by ICP-AES. Two B carriers borocaptate sodium and L-boronophenylalanine were adminis- tered to mouse tumour models. The biodistribution of the two carriers identified some differences in their tumour selectivity. L-boronophenylalanine showed significant selectivity for mela- noma. Bearman et al. (94/C3463) investigated different dissolu- tion methods for the determination of B in pharmaceuticals by ICP-AES. Acetic acid solutions gave some analytical advan- tages over other organic solvents for this element.1.8.7. Cadmium The relatively high analytical sensitivity of this element means that Cd is often determined in biological samples by FAAS. However sample pre-treatment is still required to minimize matrix interferences and improve detection limits. Both off- line and on-line sample preconcentration procedures for the determination of Cd by FAAS have been described in this review period. For off-line preconcentration of Cd in hair Su and Chen (94/1058) digested hair with HN0,-HClO and precipitated Cd with ethanolic 1 -( 2-pyridylazo)-2-naphthol (PAN) The precipitate was redissolved in dilute HNO and analysed by FAAS. On-line preconcentration techniques based on FZ systems have received wider attention in view of the distinct advantage this approach offers in terms of sample 70R Journal of Analytical Atomic Spectrometry April 1995 Vol.10throughput and reduced sample handling. Xu et al. (94/727 94/C3408) have continued to develop methods for the quanti- tative preconcentration of Cd from biological RMs for determi- nation by FAAS using an on-line FI sorbent extraction system. Two approaches were described. In the first Cd was complexed with DDC and adsorbed onto a bonded silica reversed-phase column whilst in the second Cd-NaDDC complexes were adsorbed onto a knitted reactor column. Complexes were eluted with organic solvent directly into the nebulizer of an FAAS instrument. Signal enrichment factors of between 66- and 126-fold were achieved giving detection limits of 0.1-0.15 pg 1-'.Interferences from high levels of Cu and Fe were reported in some matrices and were overcome with thiourea and ascorbic acid-phenanthroline. A similar approach was taken by Petit de Pena et al. (94/3106). In this case Cd was complexed with dithizone and adsorbed onto an activated charcoal micro-column. Organic elution was again used to transport the chelate to the FAAS. Further ETAAS methods for the determination of Cd in biological tissues and fluids have also been described. To achieve greater sensitivity Zhang et al. (94/664) electro- deposited Cd from water or urine diluted with H2S04 onto a tungsten wire coil which was placed in the furnace of an ETAAS for measurement of Cd. Wet digestion procedures for the determination of Cd and P by ETAAS were crit- ically evaluated by Tinggi et al.(94/686). Digestion with HN03-HC104 was found to be the most effective treatment. The presence of H2S0 in the digestion mixture markedly suppressed absorbance signals. Manca et al. (94/1077) used HNO alone for the microwave digestion of micro-samples of biological tissues. Tissue homogenates (100 ml) were digested with 6 volumes of acid and diluted with H 2 0 for analysis by ETAAS. Gregoire and Lee (94/2944) found the relatively new coupled technique of ETV-ICP-MS to be essential for stable isotope studies of Cd metabolism in ruminants. The authors used the technique to determine Cd and Zn isotope ratios in blood and tissues of sheep infused with enriched stable isotopes. Following acid digestion and microwave heating Cd and Zn were separ- ated from matrix components by adsorption chromatography for analysis by the coupled technique.In a study of placental transfer of Cd Soederberg et al. (94/1793) used ETAAS to determine blood Cd levels in mother- newborn pairs living in the vicinity of a copper smelter. Blood Cd levels were low in both exposed and control subjects. However a significant increase in blood Cd levels during pregnancy was observed. Blood Cd levels in newborn babies were about 70% of those in the mother and were significantly higher in babies from the industrial area. On a related topic Varga et al. (94/2115) investigated the accumulation of Cd in the human ovary by AAS. Cadmium levels increased linearly with age from 30 to 65 years but beyond 65 years ovarian Cd level declined.Ovarian Cd levels were elevated in smokers compared with non smokers. 1.8.8. Calcium The use of a fuel-lean flame for the determination of Ca in serum was described by Sommer et al. (94/C1934). A lean air-C,H flame eliminated underrecovery of Ca due to inter- ferences from the serum matrix but did not compromise analytical sensitivity. Stable isotope ratios of Ca were deter- mined by Turnlund et al. (94/2183) using TIMS in studies of Ca metabolism in very low birth weight infants. The use of a magnetic sector instrument with an automated multiple collec- tor significantly reduced analysis times and improved sample throughput. Calcium was separated from the biological matrix by precipitation as Ca oxalate and redissolved in HNO for measurement by TIMS.The effect of citric acid concentration on dentine demineraliz- ation was investigated by Sterret et al. (94/1085) using AAS to determine dissolved Ca released by citric acid treatment on dentine surfaces of bovine molars. Dentine demineralization was dependent on both acid concentration and application time. 1.8.9. Chromium Further methods for the determination of Cr in biological fluids have been described in this review period. These methods have been used to investigate Cr as an essential element for biological monitoring of occupational exposure and for the use of Cr as a tracer in physiological measurements. Optimum furnace conditions for the determination of Cr in serum and urine by ETAAS were investigated by Cimadevilla et al. (94/2401). The use of a pyrolytically coated tube with wall atomization was found to give best results.A Mg(NO,),- Ca( NO3) chemical modifier improved the detection limits for Cr in water and serum but did not improve the determination of Cr in urine. Both water and urine were analysed directly whilst serum was diluted 1 + 1 with 0.1 YO HN03 and Triton X-100. A vanadium(v) plus molybdenum(v1) chemical modifier was found by Manzoori and Saleemi (94/2934) to improve the direct determination of Cr in serum and high salinity waters by ETAAS. Atomization rates of Cr and tube lifetime were improved by this modifier. The method gave satisfactory recovery of Cr from samples with different matrices. For the determination of trace levels of Cr in serum Zhao et al. (94/681) used ETAAS with an angled platform following dilution of the sample 1 + 4 with 0.5% HNO,.In the ETAAS method described by Zhang et al. (94/ 1066) serum was digested with HC104-H20,-HC1. This method was used to examine serum Cr levels in healthy and diabetic individuals. Christensen et al. (94/ 927) also employed ETAAS with Zeeman-effect background correction to determine reference values for Cr in whole blood and serum. Improved determi- nation of Cr in whole blood was afforded by solubilization with the proteinase subtilin. The reference values obtained were in agreement with previous data. A 90% tolerance interval of 0.37 pg 1-' for Cr in whole blood was reported. The authors also described an internal quality control procedure for moni- toring analytical performance of the method.The technique of RIMS was used by Estler and Nogar (94/1006) to determine Cr in urine. Acid digested urine samples were air dried on tantalum ribbon filaments placed in the ionization region of a time-of-flight spectrometer and excited with a laser operating at 12 Hz. Aqueous standards and urine both spiked with ''Cr were used for calibration. Chromium was quantitated by measuring the isotopic abundances of the four stable Cr isotopes. Veillon et al. (94/ 3184) also used MS to determine Cr in urine. In their method the mass spec- trometer was coupled to GC for chromatographic separation of the volatile Cr-trifluoroacetic acid chelate. The Cr(TFA),+ ion was measured in the 356-360 m/z region. The LOD was 0.03 pg 1-' and accuracy was verified by analysing CRMs.The group used the method with enriched 53Cr stable isotope to measure blood volume. The method was evaluated by direct comparison with the conventional ''Cr radiolabel method. As discussed by the authors this stable isotope method is particu- larly suited to the study of blood volume changes in pregnancy and in young children. The relationship between air Cr exposure urinary Cr concen- trations and health effects in Cr electroplaters was investigated by da Silva et ul. (94/1801). Urine Cr levels were determined by ETAAS. Nasal septum ulceration was observed in workers having urinary Cr levels above 30 pg Cr per gram of creatinine and who were exposed to air Cr concentrations above 0.175 pg m - 3 for hard plating and 0.064 pg m - 3 for decorative Journal of Analytical Atomic Spectrometry April 1995 Vol.10 71 Rplating. The corrosion behaviour of Cr containing dental alloys in artificial saliva was investigated by Stratzel and Viohl (94/830). Metals released into solution by the saliva treatment were determined by AAS. Alloys with a high (>20%) Cr content exhibited high corrosion resistance. An interesting observation of species differences in the distribution of Cr following oral and intra peritoneal administration of CrV1 was made by Kargacin et al. (94/811). The authors hypothesized that differences in the organ concentrations of Cr observed between mice and rats could be due to differences in the reduction of CrV1 and in binding of Cr to haemoglobin. 1.8.10. Cohaft A critical study of Co determination in urine by Zeeman- effect ETAAS was conducted by Minoia et al.(94/1684). Urine samples were diluted 1 + 4 v/v with a 0.2% Mg( N03)2 chemical modifier for analysis. A 58C0 spike was added to samples to investigate the behaviour of Co during the atomization process. The method was assessed by comparison with an NAA method and gave a limit of detection of 0.28 pg 1-'. Different tissue digestion procedures and chemical modifiers for the determi- nation of Co in bovine liver by ETAAS were evaluated by Campos et ul. (94/640). Neither Mg(NO,) or Pd(N03)2 gave any significant improvement in analytical performance. Optimum results were obtained with a L'vov platform an ashing step at 1200 "C and a cool down step before atomization. Aqueous standards gave acceptable performance.Dry ashing and dissolution in sub-boiling 0.5% HN03 was the sample digestion procedure adopted by Xu (94/1094) to determine trace levels of Co in hair by ETAAS. Sample recoveries of 94-105% and a repeatability of <5% RSD were reported. The quantitation by AAS of Co in ternary complexes formed between antihistamines Co and isothiocyanate ions was used by Ayad et al. (94/772) for the analysis of antihistamines in pharmaceutical preparations. The complexes were extracted into benzene for analysis. This indirect method was compared with quantitation of the extracted ternary complexes by UV-VIS spectrophotometry. Both methods gave comparable results to those obtained by a standard reference method. 1.8.1 1. Copper Methods for the determination of Cu in biological tissue and fluids continue to be developed for investigations of copper metabolism.Tahan and Romero (94/696) evaluated an ASV method for the determination of Cu in plasma by comparison with an established ETAAS method. The correlation between the methods was 0.998. Samples from healthy individuals and renal patients were analysed by both methods following microwave mineralization. Mean concentrations of 1261 pg 1 - ' and 760 pg 1-' were found for renal patients and controls respectively. A microsample injection FAAS method was devel- oped by Yan and Jiang (94/1232) for the quantitative determi- nation of Cu and Zn in microlitre samples of whole blood taken from the ears of Chinese children. Accurate quantifi- cation was achieved with 25 p1 samples diluted ten-fold with 0.05% Triton X-100.An LOD for Cu of 0.04mg 1-' and a repeatability of better than 6% were reported. Copper levels in liver biopsy samples from healthy subjects and subjects with Wilson's disease were determined by Janousek (94/1038) using FAAS. Levels of Cu in liver samples from subjects with Wilson's disease were 244 and 250 pg g-' compared with levels of 4-35 pg g-' in healthy individuals. The injuence ofage and gender on Cu status was investigated by Milne and Johnson (94/2246). Plasma Cu was quantitated by FAAS following a simple dilution with distilled H20. Plasma Cu and caeruloplas- min levels were significantly higher in women and were increased further by oral contraceptive use. Plasma Cu was also significantly affected by age. Serum Cu is predominantly bound to the plasma protein caeruloplasmin.To quantify unbound Cu Cocho et al. (94/2121) extracted this fraction by chelation with APDC and extraction into IBMK. Copper in the organic extract was quantified by ETAAS with a L'vov platform. Reference levels of caeruloplasmin-free Cu were 0.78-1.84 pmol 1-' and 0.86-1.83 pmol l-' for women and men respectively. The determination of Cu has been used by several groups to indirectly quantify other biological and pharmaceutical compounds. For the determination of free fatty acids (FFAs) in biological samples Liu et al. (94/1755) reacted Cu ions with FFAs extracted into chloroform-hexane-methanol to form the copper soaps. Copper in the organic phase was determined by AAS. Recovery of FFAs from plasma was 96-102%.Satisfactory agreement with a colorimetric method was achieved. Jin et al. (94/2800) developed an ETAAS method for the determination of Cu following preconcentration on a Nafion modified electrode. The method was used to indirectly quantitate the anticancer drug nitrocaphamum by quantifying Cu after competitive exchange between Cu ions and the drug on the electrode. The determination by FI-AAS of Cu released from entrapped Cu" carbonate was used by Garcia-Mateo et uf. (94/697) to indirectly quantify glycine in pharmaceutical preparations. The Cu" carbonate was physically entrapped in polyester to form a solid resin reactor which was connected to the FI system. Immobilized Cu" was released by complexing with glycine in the pharmaceutical preparations and monitored by AAS.Linear calibration was achieved for glycine concen- trations up to 35 mg 1-' and the LOD was 1.2 mg 1-'. 1.8.12. Gevmunium To overcome strong interferences from both Na and S042- on the direct determination of Ge in biofogicaf samples by ETAAS Feng et af. (94/C3412) employed a NH4N03- Ba( N03),-Pd( N03)2 chemical modifier. Germanium could be accurately quantitated in solutions containing up to 600 mg 1-' Na,S04 using this modifier. A range of linearity up to 800 pg 1-' and a limit of detection of 6 pg 1-' were achieved. Shi et al. (94/3517) also used Pd as a chemical modifier for the determination of Ge and Sr in serum by ETAAS. Serum samples were diluted 1 + 4 v/v with 10 pmol 1-' HN0,-0.1% Triton X-100 and injected into a graphite tube pre-treated with 20 pg Pd.1.8.13. Gold Zhang et al. (94/C1905) applied HPLC and FI coupled with ICP-MS to the determination of Au in erythrocytes from arthritis patients undergoing treatment with gold-containing drugs. Chromatographic separation of erythrocyte haemolysate and solubilized membranes revealed both low M and high M gold containing species. Erythrocyte Au was not principally bound to haemoglobin but to a 30000 u species. Uptake inhibition studies indicated that dicyanogold ions enter erytho- cytes by some route other than the membrane anion channel. 1.8.14. Indium The quantitation of ultratrace elements in biological samples by ETAAS often requires chelation and solvent extraction procedures to achieve the necessary analytical sensitivity. This approach was adopted by Zheng et af.(94/985) for the determination of In in body fluids and tissues. Following acid digestion and dilution with NaC1 Na2S203 and hydroxyl- ammonium chloride In was extracted as an ion pair with Aliquant 336 into hexane-IBMK and back extracted into aqueous HNO for analysis by ETAAS. Measurements were made with Smith-Heiftje background correction and Pd was used as a chemical modifier. Calibration was linear from 72R Journal of Analytical Atomic Spectrometry April 1995 Vol. 101-1Opg 1-' and an LOD in tissues of 5-long g-' was achieved. 1.8.15. Iodine Improved sensitivity over existing colorimetric and spectropho- tometric techniques for the determination of I in biological media was reported by Burakov et al. (94/2929) using intracav- ity laser spectroscopy (ICLS).By directing the laser at the vapour above the heated liquid sample in a closed cell urinary I concentrations down to 15 pg I-' could be accurately meas- ured with a precision better than 10%. Vanhoe et al. (94/2554) showed that the oxidation state was an important factor to consider in the determination of I in biological samples by ICP-MS. An unstable signal and erroneously high recoveries were obtained for I in milk samples acidified with HNO,. Good recoveries and agreement with certified reference values for three milk RMs were obtained when samples were diluted with NH solution. Human serum samples diluted with HNO or NH solution gave comparable results. 1.8.16. Iron Two reviews on the determination of Fe in clinical specimens have been published this year.The specialized techniques of Mossbauer spectroscopy electron diffraction and EXAFS were reviewed by Dickson (94/C3115). The use of the techniques to investigate Fe overload conditions was discussed. Andrade et al. (94/1655) undertook a comprehensive review of AAS and UV spectrophotometric methods. Methods for the determi- nation of Fe continue to be developed for the study of Fe metabolism disorders. To determine liver Fe in needle biopsy samples Preston (94/C3121) developed a rapid microwave digestion method for FAAS which overcame the limitations of conventional open vessel acid digestion methods. Digestion of 3-10mg samples of tissue was achieved in 60s with an HN03-H202 mixture. The method was used to determine liver Fe concentrations in patients with idiopathic haemo- chromatosis.Liver Fe concentrations in these subjects ranged from 79 to 690pmol g-' compared with reference values of 3-32 pmol g-'. Complete removal of Fe from biological matrices was found by Flory et al. (94/2532) to be necessary for the accurate determination of stable Fe isotope ratios by FAB-MS. Isolation of Fe from the biological matrix was also recommended by Oshima (94/1709) for the determination of inorganic and haem Fe in liver by Zeeman-effect FAAS. Haem and inorganic Fe were removed from liver proteins by acid treatment and extraction into IBMK. Inorganic Fe was sub- sequently separated from haem Fe by back extraction into 1% HCl. Iron was determined by Zeeman-effect FAAS in both aqueous and organic extracts. 1.8.17.Lead There appears to be no abatement in the number of papers published on the determination of Pb in blood and other biological fluids and tissues. Concerns over the low level toxicity of Pb often referred to as sub-clinical toxicity have undoubtedly stimulated much of this recent work. Unfortunately there is little in terms of novel analytical method- ology and many of the papers simply describe modifications to established methods. The Australian standards organization Standards Australia have published standard procedures for the determination of Pb in blood using both FAAS and ETAAS (94/2602,94/2603). In the former method Pb was chelated with APDC and extracted into butyl-1-acetate for determination in an air-C,H flame. The method gave satisfactory performance for blood lead levels upto 6 pmol 1-'.For determination by ETAAS blood was diluted with an NH,H,PO,-Triton X-100 chemical modifier. The method was applicable for the determination of 0.25-6 pmol 1-' Pb in blood. The effectiveness of different chemical modifiers for the determination of Pb in blood by ETAAS was evaluated by Yo0 and Kwon (94/1667). Both (NH,),HPO and ( NH4),HPO4-PdC1 chemical modifiers gave good agreement with CRMs but better analytical repeat- ability was obtained with (NH,),HPO alone. Electrothermal AAS methods for the determination of Pb in blood using different background correction systems have also been described. Zeeman-effect correction with STPF conditions were used by Patriarca and Morisi (94/789) whilst Bosnak et al. (94/642) used platform atomization with continuum source correction.The reported detection limits indicated 20-fold better sensitivity with the latter method. The analytical difficulties of determining Cd and Pb in urine were discussed by Sesana and Baj (94/799) who proposed a direct method using ETAAS with Zeeman-effect background correction. Using the method the authors reported an upper reference limit of 26.4 pg 1-' for Pb in urine. Chen and Littlejohn (94/712) applied ETAAS with probe atomization to remove chemical interferences in the determination of Pb in urine. Samples were diluted 2-12.5 fold for analysis. Peak area measurements were necessary for accurate quantitation and the results were in good agreement with those obtained by an established chelation/extraction method.A limit of detection of 4 pg 1-' was obtained. Of more interest is the application of ICP-MS to the determination of Pb in biological fluids particularly in relation to the identification of sources of exposure through isotope ratio measurements. Stroh (94/2345) described a solution nebulization ICP-MS method for the determination of Cd and Pb in whole blood which used NH solution and Triton X-100 for sample dilution. Improved accuracy and precision were achieved with ID rather than external standards calibration. The ICP-MS determination of Pb isotope ratios in blood samples from Saudi children and samples of traditional cos- metics and remedies enabled Al-Saleh et al. (94/984) to estab- lish that the cosmetics and remedies were the likely sources of excessive Pb exposure rather than car exhaust emissions.Bayly and colleagues (94/C3117) also used isotope ratio ICP-MS to confirm the source of Pb in a case of Pb poisoning due to imported traditional remedies in the UK. A method for the simultaneous determination of Bi Pb and T1 in plasma and urine by ICP-MS was described by Mauras et al. (94/2614). The method was found to give better analytical sensitivity than ETAAS. Dale et al. (94/2795) undertook a comparative study of ICP-MS and TIMS for the determination of low levels of Pb in body fluids. The'poorer accuracy of ICP-MS compared to TIMS was more than compensated for by'the minimal sample preparation required and greater sample throughput. Reference values for Pb in blood cind urine have been stated by several groups.Mauras et al. (94/2614) reported levels of 8.2 nmol I-' for plasma Pb and 32 nmol 1-' for urine Pb in a French population Using ICP-MS Nuttall et al. (94/2613) determined an upper normal reference limit of 100 pg 1-' for whole blood Pb in a group of non-occupationally exposed Americans. Mean blood Pb levels of 10.7 pg dl-' in men and 7.9 pg dl-' in women for an adult population in Barcelona were established by Schumacher et al. (94/1798). The authors concluded that Pb exposure was not an environmental health problem in the city. A study of blood Cd and Pb levels in patients with end stage renal failure by Holding et a!. (94/C3118) indicated no evidence of accumulation of these elements nor any effect of haemodialysis. An ETAAS method for the determination of Pb in HNO digested primate bone samples was described by Subramanian et al.(94/807). The quantitation of Pb required STPF con- ditions chemical modification with Pd(N03) and standard additions calibration. Levels of Pb in trabecular bone and Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 73 Rteeth were also determined by ETAAS in a study of bone Pb mobilization undertaken by Bercovitz and Laufer (94/939). The authors observed that the ratio of Pb in bone to Pb in teeth was reversed in subjects aged over 50 years and concluded that this was due to release of Pb from bone as a result of the high turnover rate of trabecular bone. The influence of long term occupational exposure on bone Pb levels was examined in an important study by Erkkila et al.(94/2306). Bone Pb levels were measured at four different sites representing both cortical and trabecular bone using an in uiuo XRF technique. Retired and active lead battery workers were studied. The authors observed that the use of blood Pb measurements might seriously underestimate Pb body burden and that endogenous exposure from skeletal Pb stores could be the main contributor to systemic Pb levels in retired workers. In uiuo measurements of bone Pb by L-line XRF were also made by Rosen et al. (94/2496) to estimate body Pb burdens resulting from long term Pb uptake in a suburban US population exposed to high environmental Pb levels. Bone Pb levels were three times higher (15 ppm) than those in a reference popu- lation and were similar to approximated values for Pb pro- cessing workers.1.8.18. Lithium The interference of alkali and alkaline earth metals on the determination of Li by FAES was investigated by Ozdemir et al. (94/3122). Interferences from CaO and SrO could be eliminated by using an electrically heated platinum loop in the flame of a conventional FAAS instrument. Salts of Ca and Sr remained as solid residues on the Pt loop. The atomizer did not overcome interferences on the Li signal by high concen- trations of Cl- and Po43-. A ten-fold improvement in the LOD for Li over conventional FAES was achieved with the loop. The influence of Li treatment on extracellular Ca and Mg concentrations was studied by Linder et al. (94/1843) using AAS to determine Ca Li and Mg concentations in whole blood plasma and erythrocytes.Long term Li treatment was associated with an increase in both extracellular and intracellu- lar Mg concentrations. Hypercalcaemia was evident in 21% of patients on Li treatment. 1.8.19. Magnesium An FAAS method was used by Yang et al. (94/666) to determine Mg bound to human erythrocyte membranes. Erythrocyte membranes suspended in isotonic buffer were digested with HN03-HC104 and diluted ten-fold with H 2 0 for analysis by FAAS at 285.2 nm. The concentrations of membrane bound Mg were lower in subjects with hypertension and coronary heart disease compared with healthy subjects. A simple sample pre- treatment was described by Al-Khamis et al. (94/777) for the quantification of both K and Mg in erythrocytes by AAS. Erythrocytes were washed with isotonic LiN03 and lysed by dilution (1+24) with 10mmol 1-' HC1.A value of 2.33 k0.17 mmol 1-' for packed cells was obtained which was similar to values obtained by other published methods. The evaluation of mononuclear blood cell Mg as an indicator of Mg status was investigated by Martin et al. (94/983) using FAAS. Repeated measurements of mononuclear cell Mg were made in a group of subjects. RSDs of 12 and 22% were reported for intra-subject measurements. The authors concluded that bio- logical variability and analytical imprecision precluded the use of single mononuclear cell Mg measurements as an accurate indicator of body Mg status. 1.8.20. Manganese Judging by the number of published papers there appears to have been a renewal of interest in the determination of Mn in biological samples during this review period.There is not however a specific topic to which these studies have been addressed. Different atomic spectroscopic techniques have been applied to the determination of Mn in waters and biological fluids. An ETAAS method with Zeeman-effect background correction and a L'vov platform graphite tube was developed by Apostoli and co-workers (94/1682 94/21 16) to determine Mn in serum and urine. Both sample types were diluted 1 + 1 with a 0.2% Mg(N03)2 chemical modifier solution. Recoveries for Mn in serum and urine were 95.6 and 96.6% respectively and the LOD was 0.08pg I-'. The method was used to establish Mn reference values for serum and urine in the general population of Lombardy. An ETAAS method was also used by Zhao and Sun (94/2305) for the determination of both Cr and Mn in serum of patients with glycosuria.For this method sample pre-treatment involved dilution with H 2 0 and precipitation of serum protein with Na2S04. Ma et al. (94/1075) reported the sensitive determination of trace levels of Mn and Sr in serum by ICP-AES following a three-fold dilution of the sample with 1 mol 1-' HNO,. Manganese was measured at an analytical line giving minimal spectral inter- ferences. Standard additions calibration gave recoveries of 90-105% for the method. Three methods for the determination of Mn in hair samples have been published. Preconcentration of Mn from hair by coprecipitation with the metal chelating agent PAN was used by Su et al. (94/2143). Chi and Zhou (94/2895) also employed an extraction and preconcentration technique for the determination of Mn in hair by FAAS.In this method extraction and preconcentration was achieved on-line by coupling FI to the flame spectrophotometer. Improved sensitivity for the determination of Mn in water and hair samples by FAAS was achieved by using a slotted quartz tube atom trap in the method described by Zhen et al. (94/851). A three-fold increase in sensitivity was reported but Ca Cr and Mg interfered with the determination of Mn. To prevent deficiency Mn is included in trace element supplements in TPN. However Reynolds et al. (94/C3116) reported Mn toxicity in a case of long term paediatric TPN. Blood Mn levels peaked at 1500 nmol I-'. Quantitative enzyme linked immunoassay (ELISA) usually involves a colorimetric detection system.Remy and Brossier (94/2257) described a novel approach to immunoassay measurements using Zeeman-effect ETAAS to determine biotin labelled with tricarbonylcyclopentadienylmanganese (cyman- trene). Using the biotin-cymantrene label in a standard com- petitive immunoassay for bovine serum albumin the authors produced a well defined calibration up to 200mg 1-l and accurate quantification of bovine serum albumin. 1.8.21. Mercury This review period has seen a great deal of work published on the determination of both total Hg and Hg species in biological materials. The determination of Hg in biological samples was reviewed by Satoh (94/1699) who identified an urgent need for the establishment of biological SRMs for organomercury compounds.Decomposition methods for total Hg determi- nation in biological samples have been evaluated by several groups. Four different acid digestion procedures were com- pared by Adeloju et al. (94/3130) for the determination of Hg by CVAAS. Digestion with HN03-H2S04 was found to be the most satisfactory for organomercury species. Tahan et al. (94/2187) compared conventional and microwave digestion procedures for mineralization of marine biological samples. Both procedures gave acceptable results for biological CRMs although microwave . mineralization was much faster. The mineralization procedures were used to determine blood and urine Hg concentrations in groups of Venezuelan subjects both unexposed and occupationally exposed to Hg. Both urine Hg (19.7 pg 1-') and blood Hg (20.8 pg 1-') were elevated approxi- 74 R Journal of Analytical Atomic Spectrometry April 1995 Vol. 10mately two-fold in exposed workers compared with the refer- ence population. Cold vapour AAS was also used by Zhou et al.(94/C3404) and Tian and Shi (94/2626) for the determi- nation of Hg in Chinese traditional medicines. In both methods medicines were acid digested and Hg reduced with SnC1,. For the determination of Hg in blood urine and saliva Stockinger and Muntean (94/1838) digested samples with HN0,-H202 in a high pressure microwave system. The digest was injected into an FI-CVAAS system for determination of Hg. Two separate digestion procedures were applied to the same marine biological specimen by Xu et al. (94/1789) for the determi- nation of organic Hg.Inorganic Hg was first reduced and purged with N2 for subsequent determination of organic Hg by CVAAS. Improved sensitivity over previous methods was claimed by Tasche et al. (94/1767) in a CVAAS method for the determination of Hg in urine. Careful sample preparation was essential for accurate results. An LOD of better than 0.5 pg 1-' was reported. On-line sample pre-treatment methods have also been investigated to reduce sample handling and improve sample throughput. Guo and Baasner (94/3 142) microwave digested whole blood with HC1 in a knitted reaction coil for the on-line determination of Hg by FI-CVAAS. Organic Hg species were decomposed with an acidified Br-Br- reagent prior to diges- tion. The method avoided losses by vaporization and adsorp- tion and gave recoveries of 96-100%. The same workers (94/1610) applied the same decompsition and digestion pro- cedure off-line for the determination of Hg in urine.Analysis by ETAAS has also been used by groups for the determination of total Hg. Bortoli et al. (94/804) reported a detection limit of 5 pg 1-l for Hg in plasma and 15 pg 1-' for Hg in hair using a Zeeman ETAAS method. Ma and Fang (94/2411) used a gold-coated tube for the determination of Hg by ETAAS. Mercury was released from digested samples by FI-vapour generation and trapped onto the gold-coated graphite tube for quantitation. Methods for the determination of Hg in hair continue to be developed. Total Hg in hair was determined by amalgam- CVAAS in a method described by Bruhn et al.(94/2965) which used a laboratory built amalgam unit. Different sample dissolution procedures were evaluated and a procedure using HNO digestion in sealed pyrex ampoules was selected as being the most suitable for routine analysis. Different Hg species in hair were quantitatively determined by CVAAS following acid leaching in a method described by Kratzer et al. (94/2928). Methylmercury was selectively leached from hair by HC1 washing. A method for the determination of organomercury species in marine biological samples was developed by Behlke and Uden (94/C1965). Sample preparation simply involved acid extraction of organic Hg into toluene followed by separation of Hg species on a DB-1701 capillary column. A similar approach was adopted by Emteborg et al. (94/2927) who extracted Hg as DDC complexes into toluene for reaction with Grignard reagent prior to GC-AES detection.The method gave acceptable results for a variety of marine CRMs with Hg concentrations in the ng g-'-pg g-' range. The in vitro and in vivo release of Hg from dental amalgam alloys was investigated by Berglund (94/1813) using a commer- cial analytical system based on AAS. In vivo studies showed that the type and amount of amalgam restoration had little influence on the intra-oral release of Hg vapour and did not affect urinary or blood Hg concentrations. Levels of Hg in tissues and body fluids of rats following administration of Hg vapour was studied by Eide and Wesenberg (94/1746) using CVAAS. All target organs and fluids examined with the exception of the femur showed a positive correlation with exposure concentration and molar concentrations showed the best correlation with kidney Hg.The authors concluded that human deciduous teeth may be useful indicators of Hg expo- sure and target organ burdens. An ICP-MS method for the determination of Hg following HPLC separation of mercury mercaptides was developed by Takatera and Watanabe (94/2533) for the indirect measurement of thiol groups in ovalbumin. 1.8.22. Molybdenum To eliminate interference effects on the determination of Mo in human liver by ETAAS Zeng (94/678) used an La-treated pyrolytically coated platform and BaF as a chemical modifier. Samples were microwave digested with HNO and diluted with H20. The furnace programme was lengthy having an ashing step of 210 s at 1800°C and a 75 s atomization step at 2700 "C.Extraction of Mo from biological samples with ethyl- phenylcyclohexanecarboxylic acid in CHCl and dilution with C,H50H gave improved sensitivity for the determination of Mo by AAS in a method described by Poluyanov and Akater (94/2095). Soltani-Neshan et al. (94/2650) developed an ICP-MS method for the determination of stable Mo isotopes in biological samples. The method was sufficiently sensitive for the quantitative determination of '*Mo and looMo at pg I-' and ng g-' levels respectively in urine and faeces. The group (94/3192) used the method to examine absorption and reten- tion of Mo in adults after oral administration of a stable Mo isotope tracer. Interestingly differences in the main route of Mo elimination were observed between subjects with some eliminating Mo mainly in faeces and others mainly in urine.1.8.23. Nickel The liquid-liquid extraction sample pre-treatment for determi- nation of Ni in biological samples by ICP-AES described by Alonso et al. (93/1034) in the previous review was used by the same group (94/685) to determine Ni by ETAAS. An LOD of 0.1 pg 1-' for Ni in biological matrices was achieved with ETAAS as compared with 0.5 pg 1-l for ICP-AES. Patriarca and Fell (94/2954) reported an improved ETAAS method for the determination of Ni in serum. Sample treatment was a 1 + 1 v/v dilution with 1% HNO and 0.25% Triton X-100. Acceptable results for serum RMs were obtained using aqueous calibration and deuterium background correction. Comparable sensitivity and accuracy to Zeeman ETAAS methods were achieved with this new method.The determination of Ni in biological matrices by ID-GC-MS was described by Aggarwal et al. (94/1325). Instrumentation reagents digestion procedures and control of contamination were discussed and specific methods for the determination of Ni in semen and urine were described. Alves et al. (94/1281) examined cryogenic desolvation to overcome polyatomic interferences on the determination of As Ni and V in biological samples by ICP-MS. Interferences were attenu- ated to manageable levels and addition of 2% H2 to the aerosol gas flow produced a two- to three-fold enhancement of the analyte signal. Samples were diluted with 1% HNO and introduced by FI. Detection limits for Ni in urine river water and seawater ranged from 0.03 to 20 pg 1-'.White and Boran (94/767) developed a simple method for the direct determination of Ni in urine to assess the suitability of such measurements for biological monitoring of occupational exposure. The method was used to monitor urinary Ni concen- trations in two groups of electroplaters. Two groups have examined sample decomposition methods for the quantitative determination of Ni in hair by FAAS. Wang (94/1842) digested hair samples with HN0,-H,02. Wang (94/1076) examined various decomposition methods and found the best results were obtained with dry ashing and subsequent digestion with HNO,. Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 75 R1.8.24. Platinum methods for atomic spectroscopic analysis.The suitability of Extensive use of platinum drugs in the treatment of cancer continues to stimulate studies on the measurement of Pt in biological samples. Several papers have reported the evaluation of methods for the determination of 'free' Pt and Pt species in biological fluids and tissues. A comparison of isotope dilution GC-MS and ETAAS for the determination of Pt in urine plasma and plasma ultrafiltrate was undertaken by Aggarwal et al. (94/769). For GC-MS analysis Li-bis-(trifluoroethy1)di- thiocarbamate was used as the chelating agent and enriched 192Pt as an internal standard. For the ETAAS measurements calibration with aqueous standards and standard additions was investigated. Good agreement between the methods was observed for Pt determination in urine but there were signifi- cant discrepancies in the concentrations of Pt in whole plasma and ultrafiltrate determined by the two methods.Both Zhao et al. (94/1407) and Cairns et al. (94/C3495) described methods for the determination of Pt species by chromatography coupled to ICP-MS. In the first of these studies satisfactory separation of cisplatin hydrolysis products and cisplatin-amino acid conjugates was achieved by reversed- phase ion-pair chromatography using Na dodecylsulfate or heptanesulfonate as ion-pairing agent. An LOD of 1 pg 1-l Pt was obtained with an injection volume of 100 pl. The second group separated Pt species in a novel Pt drug by reversed- phase HPLC using isocratic and gradient systems. The chroma- tograph was coupled to the ICP with a novel interface design based on cryogenic desolvation and thermospray nebulization.The effect of different cisplatin perfusion modes on lung morphology and lung function in pigs was investigated by Ratto et al. (94/1720). Platinum concentrations in urine plasma and tissues were determined by ETAAS. Changes in lung morphology and impairment of gas exchange were independent of the perfusion technique used but highest Pt concentrations in all fluids and tissues were detected when cisplatin was administered by a stop flow technique. To measure Pt drug- DNA interactions in human tissues Pourier et al. (94/1743) used both immunoassay and AAS methodologies. Total DNA-Pt adduct was quantitated by AAS and a specific fraction of this adduct was detected by anti cisplatin-DNA enzyme linked immunosorbent assay (ELISA).This approach was taken to evaluate the use of DNA adduct measurements for clinical investigation and for occupational and environmental biomonitoring. The study demonstrated a strong correlation between failure to form Pt-DNA adducts detected by ELISA and failure of cisplatin therapy. The same correlation was not observed for total DNA-bound Pt. 1.8.25. Rare earth elements Lopez-Molinero et al. (94/2111) found that the addition of KCl to calibration standards overcame inorganic matrix inter- ferences on the determination of Eu in biological samples by ICP-AES. Lai and Jamieson (94/3164) applied ICP-AES to the determination of Dy in monkey serum following adminis- tration of a new contrast medium for magnetic resonance imaging.Serum samples were diluted 100-fold with. 1 mol 1-' HC1 and calibrated against matrix matched standards. 1.8.26. Selenium Much of the continued interest in selenium lies in its role as an essential element and its role in the prevention of disease. Methods are required to determine Se at trace levels in biological fluids to clearly establish deficiency states. The determination of Se in environmental and biological materials was reviewed by Izbash et al. (94/950). The difficulty in accurately determining Se in biological matrices is well recog- nized and activity has focused on identifying the most appro- priate sample pre-treatment and chemical modification commonly used chemical modijiers for the determination of Se in serum and urine was critically evaluated in a comprehensive study by Johannessenn et al.(94/2186). Addition of 7.5 pg Pd and 5 pg Mg(N03)2 to samples of serum and urine in the graphite tube was found to be the most effective for stabiliz- ation of all the important organic and inorganic Se species. Analysis of serum and urine CRMs using this modifier gave acceptable results. Kao et al. (94/861) described a method for the determination of total Se in urine and serum with Pd-Ni-NH,NO for chemical modification. Limits of detection for serum and urine samples were 2.36 and 4.9 pg I-' respect- ively. A simpler chemical modifier of Pd and Triton X-100 was reported to be effective for the Zeeman-effect ETAAS determi- nation of Se in serum and whole blood by Ciapellano et a!. (94/1685) Zhu et al.(94/2409) and Rai and Mei (94/C3402). Using this modifier Ciapellano determined reference values for blood Se in an Italian population. The underlying chemistry of the stabilization of Se with noble metals was investigated by Hirano et al. (94/3311). The importance of analysing Se in its active oxidation states was highlighed by Takanada and co-workers (94/1702,94/1704). The group described a method for the analysis of SeIV and SeV' by ETAAS following selective extraction of SeIV on an ion-exchange resin with bismuthiol-I1 sulfonate functional groups. Selenium(1v) was adsorbed onto the resin in 0.1-6 mol 1-l HCl. The loaded resin was injected into the graphite furnace as a slurry. The method was used to determine Se in amino acid and TPN injections. Hydride generation methods have also been developed to eliminate matrix interferences on the determination of Se in biological samples.Hydride generation systems have been coupled to a variety of different atomic spectroscopic detection systems. Hydrogen selenide was concentrated in situ onto a silver coated graphite tube for determination by ETAAS in a method developed by Ni et al. (94/2185). Trapping onto a silver-coated tube offered a less expensive alternative to Pd and was sufficient to determine Se concentrations above 20 ng g - ' in biological samples. Sample dissolution procedures and HG reaction conditions for the determination of Se by ICP- AES were evaluated by Liu and Lu (94/1776). The practical problems affecting FI-HGAAS determination of Se in biologi- cal samples were investigated by Tyson and Sundin (94/C471).Oxidative decomposition of organoselenium species was achieved with an acidified Br-Br - reagent. A water permeable Nafion tubing gas line to the quartz atomizer overcame the problem of H 2 0 vapour in the HG system. For the determi- nation of Se in serum by ICP-AES Recknagel et al. (94/1645) described a novel on-line FI-acid digestion-HG system. Digestion was carried out in a heated reaction coil to which a ultrasonic field was applied. The nebulizer of the ICP was used as the gas-liquid separator. The LOD of the system was Atomic fluorescence spectrometry is a particularly sensitive system for the determination of Se. D'Ulvio et a!. (94/742) like Tyson and Sundin digested organoselenium species with acidified Br-Br- for total Se determination by HG with AFS detection.The method was equally effective for organic and inorganic Se species and gave LODs of 0.5 and 1 pg 1-l for human urine and serum respectively. Hydride generation-AFS was also used by Yang et al. (94/1233) to determine Se bound to human erythrocyte membranes. Membranes were digested with HNO-HC104-H2S0,. The combination of LEAFS with ETA gave extremely high sensitivity for the determination of both As and Se in whole blood in a method described by Heitmann et al. (94/2951). Determination of 103 blood samples with the method gave a median value of 109 pg I-' Se for a German population. Korunova et al. (94/1697) reported serum Se levels in an adult Czechoslovak population. A wide range of values were 5 pg 1-'.76 R Journal of Analytical Atomic Spectrometry April 1995 Vul. 10determined by AAS. Mean Se concentrations were 72 pg I-' for men and 76 pg I-' for women. The authors concluded that the Se status of this population was below the European average. 1.8.27. Silicon There have been further developments in ETAAS methods for the determination of Si in biological tissues and Juids during this review period. To quantitate silicone concentrations in breast tissue Wichems et al. (94/3300) determined Si in heptane extracts of dried breast tissue using a continuum source AA spectrometer with an electrothermal vaporizer. An LOD of 6 pg I-' Si was achieved. In the ETAAS method described by Zhuoer (94/2211) addition of Ca and La to acid digested samples gave a considerably enhanced atomization signal from a pyrolytically coated tube.Ammonium dihydrogenortho- phosphate and tartaric acid were used as chemical modifiers for soft tissue and bone digests respectively. The LODs for Si in soft tissues and bone were 0.14 and 0.9 pg g-' respectively. Satisfactory results were achieved with aqueous calibration. For the quantitative determination of Si in serum and urine Prajon and Sanz-Mede1(94/2400) investigated the use of metal carbide coated graphite tubes to enhance the Si atomization signal and prevent Si carbide formation. A tungsten-coated tube and L'vov platform were found to give the best signal. With this approach no sample treatment other than a 1 + 3 dilution for serum and 1 +49 dilution for urine was necessary.All instrumentation was housed in a clean room to minimize dust contamination. The authors used the method to determine Si levels in chronic renal failure patients. No correlation between A1 and Si levels was observed except for samples with very high (> 100 pg 1-') A1 concentrations. 1.8.28. Silver A direct method for the determination of Ag in urine using ETAAS with Zeeman effect background correction was described by Minoia et al. (94/802). Urine samples were diluted 1 + 1 with a Pd-Mg(N0,)2 chemical modifier. Reasonable analytical precision (12%) and a detection limit of 0.08 pg 1-1 were reported. The authors used the method for the biological monitoring of workers occupationally exposed to Ag dust and fume. 1.8.29. Sodium and potassium Ohta et al. (94/2293) described an ETAAS method for the determination of K in biological materials which used a molyb- denum atomizer tube.Plant materials were digested with HNO3-H2O2 at 120 "C evaporated to dryness and dissolved in 1 mol 1-' HNO,. The digest was diluted 1+49 with 5 mg ml-' thiourea. The detection limit was 0.12 ng in the presence of thiourea as a chemical modifier and the repeat- ability as measured by RSD was 2.6%. 1.8.30. Strontium A method for the determination of trace amounts of Sr in human hair by FAAS was developed by Liang and Ruan (94/1073). Hair samples were digested with HN0,-H,02 in a closed PTFE vessel. Interferences from Ca and Mg on the Sr signal were supressed by the addition of EDTA to the cooled digest. Good accuracy and a precision of better than 5% were reported.1.8.31. Tin Total Sn levels in waters and serum were determined by Tao and Fang (94/C3377) using ETAAS with on-line ion-exchange chromatography and FI-HG. Tin was separated as the chloro- stannate complex from the sample matrix on a strong anion- exchange column and eluted with HNO into the FI-hydride system. Stannane was subsequently trapped onto a Pd-coated tube and atomized at 2300°C. A detection limit of 0.05 pg I-' for a 10.7 ml sample was obtained. Lin et al. (94/2410) described a method for the determination of Sn in blood by ETAAS which used KN03 as a chemical modifier. There is continued interest in the development of methods for the speciation of organotin compounds in biological samples. Sample preparation methods for the speciation of Se and Sn were examined by Donnard et al.(94/C1890). The authors concluded that open microwave irradiation systems offered the opportunity for on-line sample preparation for speciation analysis. For the determination of organotin species in fish CRMs Kumar et al. (94/2689) coupled reversed-phase ion- pair HPLC to ICP-MS. The effect of inorganic Sn on the elution of organotin species was investigated. 1.8.32. Titanium A combination of histological examination and ICP-AES was used by Fischer-Brandies et al. (94/829) to examine human bone tissue from the vicinity of titanium prosthetic implants. Titanium corrosion products mainly as particulates were identified from both titanium bolts and plates. 1.8.33. Thallium For the direct determination of T1 in urine Minoia et al.(94/801) used Zeeman-effect ETAAS with STPF conditions. Thermal stabilization of the analyte was achieved by chemical modification with Pd and Mg(N0,)2. The direct method gave comparable results with an established chelation-solvent extraction procedure. The repeatability of the method was 5 % RSD at a T1 concentration of 52pg 1-l and the LOD was 1.25 pg 1-'. The authors used the method to monitor subjects with acute TI intoxication. An FI-ICP-MS technique was used by Shibata et al. (94/1369) to determine the distribution profile of T1 and other elements along a single strand of hair. Sections of hair were digested with microlitre volumes of HNO at room temperature. The authors used the profile results to reconstruct the recent exposure history of an individual with TI poisoning.1.8.34. Vanadium To eliminate the polyatomic interference of 35C1160 on the determination of 51V in urine by ICP-MS Pretty et al. (94/2879) investigated the coupling of an on-line ASV flow system to the ICP-MS detection system. Elimination of the 35C1'60 polyatomic interference was quantitative for C1 con- centrations upto 1 g 1-' but higher C1 concentrations yielded a C10 signal overlapping that of V. 1.8.35. Zinc This reviewer was intrigued by the approach adopted by Burguera et al. (94/2248) to eliminate sample contamination problems in the determination of Zn and Cu in whole blood by FAAS. Samples were drawn directly from the forearm vein of subjects into a timed injector which was automatically controlled to pump sample mixed with EDTA and 1 mol I-' HC1-HNO to an FI system with on-line microwave mineraliz- ation.The FI system was in turn coupled to the nebulizer of an FAAS. Thus the subject became an integral part of the analytical system. Accurate quantitation required calibration with standards prepared in glycerol-H,O containing human serum albumin. Ranges of 4.8-6.5 mg I-' Zn and 0.85-1.1 mg 1-' Cu were determined in twenty samples from healthy fasted individuals. Sample throughput was 30 h-'. It will be interes- ting to note the interest shown in this approach by groups conducting research into trace element reference values. Durrant et a!. (94/2908) evaluated different chelation pro- cedures to separate Zn from biological matrix elements prior Journal of Analytical Atomic Spectrometry April 1995 Vol.10 77Rto isotope ratio analysis of Zn in biological samples by ICP-MS. A method using carboxymethylated poly(ethy1ene- imine)-poly(methylenepolypheny1ene) isocyanate CPPI was found to be the most effective for removing Na C1 and Ca ions. Acceptable results were obtained for measurements of Zn ratios in bovine milk and human urine. Results were compar- able with those obtained by an extraction procedure. To compare precision between ICP-MS and FAB-MS methods for the determination of Zn isotope ratios Friel et al. (94/1352) prepared Zn isotope enriched faecal and urine samples by ion- exchange chromatography. 1.9. Conclusions It was interesting to read Willis' account of the first clinical application of AAS (94/2245). For younger readers it may be difficult to realize what a momentous step this was.Atomic absorption spectrometry allowed the straightforward and selec- tive determination of Ca and Mg in serum and urine producing an increase in study of these elements with a greater under- standing of their role. Extension of FAAS to the determination of Cu and Zn enabled growth of clinical studies of these elements. It is perhaps ironic that the use of FAAS for the determination of Ca and Mg is now declining and being replaced by colorimetric methods not because they are superior but because they are compatible with the concept of a multi-channel clinical analyser based on measurements by molecular absorption spectrophotometry. It was difficulty with colorimetric methods which led to the emergence of AAS in the first place.In those early days concentrations of 1 ppm (1 mg 1-' or 1 mg kg-l) were considered low but developments in ETAAS ICP-AES and ICP-MS have pushed LODs lower and lower. Now Moens et al. (94/3277) report that the sensitivity of high-resolution ICP-MS operated in the low resolution mode was so great in the determination of Ag that they were limited by the size of their blank achieving an LOD of 4.3 ng 1-l whereas the true instrumental LOD was 10-100 times lower. This they indicated called for a new round in the battle against blanks. Reference values have been established for a range of ultra- trace elements using ICP-MS (94/2213) and one might hope that this will lead to a greater understanding of the role of some of these elements (e.g.B Mo) in humans and animals. However our understanding of elements that have been studied for a long time (e.g. Cu Fe Zn) is still very patchy. The use of stable isotopes and measurement by MS techniques (Section 1.3.2) is helping to follow the absorption and bioavail- ability of these elements. Studies on the toxic elements are often easier to interpret. It is intriguing to see that interest in the publication of methods for determining Pb has not abated (Section 1.8.17). There are several novel approaches to looking at these elements. For example the direct determination of Pb in bone by XRF (94/2306,94/2496) and assessment of environ- mental Cd and Pb contamination in oceans by determining these elements in the annual growth layers in the teeth of the walrus or Beluga whale by laser ablation ICP-MS (94/3263).The collaborative project reported by Cortes Tor0 et al. (94/676) has established which elements hair analysis is useful for and which give meaningless information. The cases reported by Yoshinaga et al. (94/1369) demonstrate that hair analysis when used to follow concentrations of Hg and T1 along the length of hair can reveal interesting information. Table 1 CLINICAL AND BIOLOGICAL MATERIALS. The 'Various' section which includes papers where five or more elements are included has been arranged so that similar applications appear together. Entries have been grouped as Serum plasma blood; Urine; Other biological fluids; Soft tissues; Bone and other hard tissues; Hair nails; Biological materials RMs etc. Element Ag A1 A1 A1 A1 Technique; atomization; Matrix analyte form* Urine A A;ETA; L Tissues AA;ETA;L Plasma hair Brain AA;ETA;L AA;ETA;L Serum AE;ICP;L A1 A1 A1 A1 A1 Tissues Serum Serum Algal biomass Serum LMMS;-;S AA;ETA;L AA;ETA;L _ a _ ._ 9 AA;ETA; L Sample treatment/comments A method was presented with Pd and Mg(N03)2 as chemical modifiers in a series of applications of AAS in toxicology measured with (NH,)H,PO as chemical modifier. Standard additions calibration was necessary for analysis of bone A1 concentrations in hair samples from patients on haemodialysis were similar to those of controls and were not correlated with exposure or plasma levels Interferences associated with phosphate and alkali metals were reduced by K2Cr20 as chemical modifier. Small focal increases of A1 were found in regions of brain from Alzheimer's disease patients Five emission lines were investigated and at higher concentrations 237.33 nm was suitable.The greater sensitivity at 396.15 nm was necessary for normal levels but this was subject to interference from the 396.83 nm Ca line Methods for quantitation using LMMS were discussed and a crown ether complex with cis- dicyclohexane was proposed as a standard A group of laboratories collaborated to develop a method. Standard additions calibration of samples diluted 1 + 4 with 0.02 moll-' HNO was recommended with measurement in Ta-treated tubes or pyrocoated tubes with a platform (in French) Mg(NO,) and K2Cr20 were compared as chemical modifiers in association with atomization from a L'vov platform.Comparable results were obtained but sensitivity was superior with K,Cr,O adsorb metals from contaminated water with desferrioxamine on the binding of A1 and Si to serum proteins was investigated Tissues were digested with HNO and the A1 Various algal species were tested for their ability to The effects of chronic renal failure and treatment Reference 94/802 9417 1 1 941832 94/89 1 94/1106 9411416 9411 669 9411683 94/c2021 9412924 78R Journal of Analytical Atomic Spectrometry April 1995 Vol. 10Table 1 (continued) Technique; atomization; analyte form* Element A1 Serum Matrix Sample treat ment/commen ts Reference A E;I C P; L Instrumental parameters; wavelength plasma power 941c3441 sheath gas viewing height and sample diluent were investigated and optimization provided for an LOD of 1 ppb.Recommended conditions were to use 396.152 nm 0.8 I min-' gas flow and 1 +4 dilution with 1.4 rnol I-' KCI The sample was heated at 90°C with HN0,-H,SO in a sealed silica tube. Digested sample H,O and HCI were placed into a reaction vessel and NaBH in NaOH added. The generated hydride was transferred to an electrically heated atomizer at 1100°C. Recovery of As"' (5-10 ng) was 91-108% With 0.1 g cysteine added to 10 ml urine AS'*' As" monomethylarsonic acid and dimethylarsinic acid were converted to ASH with equal efficiency when mixed with 0.7 mol I-' HCI and then with 0.65 rnol I-' NaBH,-0.1 rnol I-' NaOH. Arsenobetaine together with these As species were converted to As" when urine was heated with K,S04 and NaOH. The As" was then reduced to ASH by mixing with 3 rnol 1-' HCI followed by 0.65 moll- ' NaBH,-0.1 rnol I - NaOH.These two methods permitted differentiation between dietary and occupational exposure to As Acidified urine was digested by microwave heating and As concentrated on an ion-exchange column Conditions for fast (< 1 min) analysis were developed for STPF measurement in a transversely heated graphite tube After dilution with 1% HNO samples were nebulized and C10+ CaO+ and ArCl' were removed from the aerosol by cryogenic desolvation. Inclusion of 2% H to the plasma gas usefully enhanced analyte signals be overcome by addition of 4% ethanol adjustment to the nebulizer flow rate and standard additions calibration As and Hg were measured in samples from subjects with various occupational exposures.A risk of As toxicity was seen in motorcycle silencer manufacturers digested with HNO -H2S04-HC1 at < 130 "C. Results from non-occupationally exposed subjects were reported Arsenobetaine and arsenocholine were removed by strong cation exchange solid-phase extraction. The sample was then digested with HNO,-H,SO4-K,Cr,O,-H~O to take all the .As1'' As" monomethylarsonic acid and dimethylarsinic acid to As"' for measurement with an FI-HG technique 3300-7900 ppm and 9300-18000 ppm respectively in 16 out of 18 samples (in Japanese) final concentrations of 0.2% v/v HNO and 0.01% Triton X-100. 10 pl of diluted sample and 10 pl Pd solution were placed onto a L'vov platform in a graphite atomizer. Electrochemical heating was applied to atomize the sample for LEAF with an Nd:YAG laser excitation source A method for elimination of matrix components that contribute to polyatomic interferences was developed.Samples were digested with HN0,-H,O and taken into Tris buffer pH 9. Using an FI manifold the analyte (as the anion) was retained on an alumina column eluted with HNO and transported to the ICP. Interfering ions remained on the alumina column with ICP-MS detection in specimens from patients treated by haemodialysis Spectral and non-spectral interferences were said to Good recovery was achieved when samples were AAi-i- XRF; -;S LEAF;-;L As and Hg were found at concentrations of The blood was diluted 1 + 9 with a diluent to give As species were separated and measured by HPLC 94/c3477 As Biological materials AA;H y ;L 941637 As Urine AA;Hy;L 941663 As As Urine Urine AA;Hy;L AA;ETA;L 941877 9411 188 As Urine MS;IC P L 94/1281 As As Serum urine Urine M S;ICP;L AA;Hy;L 9411294 941 166 1 As As Hair nails Urine AA;H y;L AA;Hy;L 9411 700 9411729 As As Chinese patent medicine Blood 9412 134 941295 1 As Biological materials MS;ICP;L 9412973 As Plasma MS;ICPL Journal of Analytical Atomic Spectrometry April 1995 Vol.10 79RTable 1 (continued) Technique; atomization; analyte form* MS;ICP;L Element Matrix Au Red blood cells Sample treatment/comments Reference Binding of Au to red cells from patients treated with 94/c 1905 gold compounds for arthritis was investigated. Species were separated by HPLC and the Au measured by ICP-MS See Al ref. 941C2021 941c2021 HNO and plasma were microwave heated in PTFE Tissues from cancer patients undergoing boron 9418 13 9411635 containers neutron capture therapy were digested with HNO in closed PTFE vessels.Operating conditions and nebulizer type giving best response were determined Ilistribution tumour uptake and minimum effective tumour concentration for boron neutron capture therapy were studied Samples were diluted 1 +4 with 0.14 mol I-' HNO containing Be internal standard. The lens voltage and nebulizer flow rates were optimized to give the best B signal and concentrations in reference specimens were 4.1-25.8 pg 1-'. See also Various ref. 9412213 washed and suspended in tissue culture medium. A solution of CaCl in 9.5 mmol 1-' HCl was added and 20 p1 introduced to the pyrolytic coated graphite atomizer. An LOD of 0.05 mg I-' of suspension was found To facilitate the solubilization of drugs dissolution in organic solvents rather than acid digestion was undertaken. CH,COOH was preferred to CH,OH heptane or H20 A method was presented with Mg(NO,) as chemical modifier in a series of applications of AAS in toxicology Hi was measured in tissue samples digested with HN0,-H2S04 (4+ 1) using Pt as the chemical modifier.Bone was homogenized prior to digestion An FI continuous precipitation and filtration system was developed for the indirect measurement of papaverine strychnine and cocaine. The alkaloids were mixed with a Bi14- reagent to give the ion pairs which precipitated from solution. The decrease in Bi was proportional to the concentration of alkaloid investigated none was detected <0.007-0.067 pg 1-' and the response to therapeutic colloidal Bi salts was followed.Samples were diluted with HNO for analysis administration of a tracer dose Cells incubated with boronophenylalanine were Normal levels for healthy French adults were Reference values for healthy adults were Stable isotopes were monitored for up to 600 h after 9411 352 See Al ref. 9411416 9411416 The influence of Li on intracellular and extracellular 9411843 concentrations of Ca and Mg was determined was preferred and provided accurate reproducible results The delaying effects on bone age of exposure to high concentrations of F were examined Infants were fed diets enriched with 46Ca to study Ca metabolism. Saturated ammonium oxalate at pH 10 was added to samples to precipitate the Ca.The washed precipitate was dissolved in HNO for measurement of 44Ca 46Ca and 48Ca by magnetic sector TIMS Historical work with the first AAS instruments was described in a personal account by a pioneering worker The distribution of Ca was mapped in solid samples with a spatial resolution of 20 pm Studies to investigate intestinal absorption and bioavailability of essential elements using stable isotopes were presented to illustrate the value of MS In the preparation of a serum RM a fuel-lean flame 941c1934 9412 1 73 9412 183 Au B Algal biomass Plasma _ * _ * _ 7 AE;ICP;L Tissues AE;ICP;L B Tissue plasma Serum AE;ICPL MS;ICP;L B B 94/21 14 9412 5 3 6 Melanoma cells AA;ETA;L B 9413026 B Pharmaceutical solutions AE;ICP;L 94lC3463 Be Bi Bi Urine Tissues Alkaloid drugs AA;ETA;L AA;ETA;L AA;F air-C2H,;L 941800 9411047 9412204 Bi Bi Plasma urine Serum MS;ICP;L MS;ICPL 9412614 941261 5 Ca Plasma MS;TI;S Tissues Blood erythrocytes plasma LMMS;-$ AA;F;L Ca Ca Ca Serum AA;F air-C2H2;L Ca Ca Serum Faeces urine Ca Serum urine AA;F;L 9412245 Ca Ca Biological materials Biological materials XRF;-;S MS;ICP;L 9412505 9412543 80 R Journal of Analytical Atomic Spectrometry April 1995 Vol.10Table 1 (continued) Element Matrix Technique; atomization; analyte form* Sample treatment/comments Cd Blood Cd Urine Cd Tissue Cd Hair Cd Tissues Cd Blood Cd Placenta Cd Blood Cd Ovary Cd Blood Cd Urine Cd Blood tissues Cd Biological materials Cd Blood Cd Urine Cd Hair AA;ETA;L AA;ETA; L AE;MIP;Sl AA;F;L AA;ETA;L AA;ETA;L AA;-;- AA;ETA;L AA;-;- MS;ICP;L MS;ICP;L MS;ICP;L AAETA;L AA;ETA;L AAF;L Cd Urine AA;ETA;S The sample was acidified to 0.1 moll-' with HzS04 and the Cd electrodeposited onto a tungsten wire coil.The coil was placed inside the graphite furnace for electrothermal atomization. A detection limit of 0.1 ng ml-' was reported Cd Biologcal materials A A; ETA; L A procedure with HN0,-HClO was the most effective of three digestion methods investigated Cd Biological materials urine AA;F;L An on-line FI manifold was constructed to prepare a DDC complex which was trapped on octadecyl functional groups attached to a silica sorbent. The chelate was eluted with CH,OH and transferred to the nebulizer. The sampling rate was 85 h-' with an enrichment factor of x 20 Various methods were presented in a series of applications of AAS in toxicology Various methods were presented in a series of applications of AAS in toxicology A 1% slurry of lyophilized sample in 10% HNO was fed into an MIP via a V-groove Babington nebulizer (9+ 1) and the residue dissolved in 10 ml H,O.The solution was mixed with 1.5 ml ethanolic 0.1% 1-(2-pyridylaz0)-2-naphthol and 1 ml pH 10 NH,-NH4Cl buffer to give a precipitate which was collected after 10 min dissolved in HNO and analysed (in Chinese) Tissues were homogenized with 4 volumes of pH 7.6 10 mmol 1-' Tris buffer and 100 pl mixed with 600 pl HNO in a sealed tube. After at least 12 h the tube was heated for 2 min on a defrost cycle in a microwave oven cooled and reheated twice. The solution was diluted with H,O and analysed Maternal and cord blood from subjects living near to a Cd-smelter were measured This study established interactions between Cd and the essential elements Cu and Zn during pregnancy correction at the analytical line was used to eliminate potential d.c.emission interference years and the analysis of RMs calibrated by ID 'Tracecon' pre-treatment system for FI-ID measurement After digestion with HNO and separation from potential interferents in the test matrix by adsorption chromatography ETV was used to introduce the sample for measurement of isotope ratios A column of activated C was included in an FI system in which a Cd-dithizone complex was concentrated. The trapped analyte was eluted by IBMK and enhancement of up to 130-fold was achieved Normal concentrations were found in patients with chronic renal failure and on treatment with haemodialysis 1 ml urine+ 1 ml HNO was heated in a sealed phial at 60 "C for 1 h.An LOD of 0.03 ng ml-' was achieved using a system with a 300 W Xe arc lamp as the radiation source for AAS An on-line preconcentration system was developed with adsorption of a Cd-DDC compex onto a solid support and subsequent elution with IBMK. An enhancement factor of x 66 was achieved using 5 ml of sample and the LOD was 0.1 pg 1-1 Hair 0.2 g was heated with 5 ml HN03-HC10 The Smith-Hieftje approach to provide background Ovarian Cd levels increase with age between 30-65 Samples were diluted 1 + 9 with NH,-Triton X-100 Interference from Mg and Na was removed with a AA;F air-C,H,;L Reference 941664 941686 941727 941798 941799 941 1010 9411058 9411 107 9411793 9411804 94fC1948 9412115 9412345 94/28 1 1 9412944 9413 106 94/C3 1 18 9413301 941C3408 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 81 RTable 1 (continued) c o Antihistamines AA;-;L 941712 c o Hair c o Urine Cr Plasma Cr Blood serum Cr Urine Cr Cr Cr Cr Cr Cr.Cr Cr Cr Cr Cr Cr Serum Blood plasma blood cells Urine Biological materials Pharmaceuticals Serum urine Urine Serum Biological materials Urine Blood Urine AA;ETA;L A A;ETA; L AA;ETA;L A A;ETA; L RIMS;-;S AA;ETA;L AA;ETA;L RIMS;-$ AA;ETA;L AA;ETA;L AA;ETA;L M S;I CP; L AA;ETA;L MS;ICP;L MS;GC;L MS;GC;L MS;ICP;L 941 1096 9411684 94/68 1 941927 941 1006 9411066 9411 101 941 1 32 1 9411 702 941 1 7 10 9412401 9412819 9412934 9412973 9413 184 9413200 9413258 Technique; atomization; analyte form* Sample treatment/comments Reference Element Matrix c o Liver AA; ETA;L Two digestion procedures were investigated for the 941640 preparation of dried powdered liver.5 ml HN0,-HC104 ( 3 1) was added to 500 mg sample at room temperature for 3 h heated to 120°C for 1 h to 180°C for 1 h and then to 210°C for 30 min. The solution was diluted with H,O to 25 ml. Similar results were obtained when the second method with just HClO was used. Chemical modifiers [ Mg( or Pd( NO,),] were not necessary antihistamine drugs thiocyanate and Co and extracted into CsH6. Measurement of Co provided the indirect determination of the antihistamines 0.5% HNO (in Chinese) Ternary complexes were formed between the Residues after ashing at 550°C were dissolved in Samples were diluted 1 + 4 with 0.2% Mg(N03)2 The sample was diluted 1 5 with 0.5% HNO and 20 p1 applied to an angle-platform atomizer (in Chinese) Blood samples were pretreated with a proteinase Subtilisin A.Reference ranges for Danish subjects were 0.04-0.35 pg 1-' and 0.12-0.34 pg 1-' for serum and blood respectively lJrine digested with HN0,-H20 was dried onto a tantalum ribbon. The ribbon was placed into the spectrometer heated to 700°C and the atoms ionized by laser radiation for detection of the Cr isotopes by MS 0.2 ml serum was mixed with 0.4 ml HClO,+0.1 ml H20,+0.4 ml 0.3 moll-' HCl and 20 p1 were placed into the graphite furnace to measure Cr. The LOD was 0.418 pg 8-l (in Chinese) Erythrocytes platelets and leucocytes were separated by density gradient centrifugation (in German) RIMS with ID was found to be an accurate technique for measurement of Cr in complex samples oxidation states of Cr Mn Se and V were considered (in Japanese) Trace elements were measured in components of total parenteral nutrition solutions (in Japanese) Serum was diluted 1 + 1 with 0.2% Triton X-100 in 0.1% HNO urine was untreated and a mixture of Mg( NO,),-Ca( N03)2 chemical modifier was added.Wall atomization was from pyrocoated graphite tubes. Other atomization techniques and graphite surfaces were investigated in this study ASV with a flow-through cell was used to isolate metal ions from C1 and other species likely to give polyatomic MS interferences. The ASV cell was coupled directly to the ICP-MS system A chemical modifier with 20 pg V was investigated.' In the recommended procedure samples were diluted 1 + 1 with 0.1% v/v Triton X-100 and standard additions was used for calibration See As ref. 9412973 A volatile chelate with trifluoroacetylacetone was Various analytical approaches for investigation of the formed for measurement by GC-MS. The LOD was 0.03 ng g-' and results were comparable with those given by other techniques. Total Cr and different isotopes could be determined Cells labelled with ',Cr were used to measure blood volume changes. Measurements were made by GC-MS and results were identical to those given by an established procedures using a radioactive label optimization of pH and ionic strength of the mobile phase the ICP-MS detector provided for very low LODs.Similar work with Ni and V was also reported (3r"' and CrV' were separated by HPLC after 82R Journal of Analytical Atomic Spectrometry April 1995 Vol. 10Table 1 (continued) Technique; atomization; Element Matrix analyte form* c u Pharmaceuticals AA;F;L Sample treatment/comments Samples of pharmaceutica1 solutions were pumped through a polyester resin. Cu trapped within the resin was dissolved by glycine in the sample and measured in an indirect method for the determination of the glycine See Cd ref. 941727 Samples were solubilized with HNO,-H,O for the simultaneous measurement of Cu Fe Mn and Zn. Better results were obtained with Smith-Hieftje background correction compared with a deuterium system or with no correction Effect of an infection on the Cu Fe and Zn content of tissues was studied.Lyophilized tissues were digested with HN0,-H,O See Cd ref. 9411010 5-20 mg tissue was heated at 550°C and the ash dissolved in 2 ml of 3 mol I-' HNO (in Czech) A commercial colorimetric kit method was less precise and gave higher concentrations when compared with measurements of Cu by FAAS See Cr ref. 9411101 25 p1 blood (collected from the earlobe) + 250 p1 0.05% Triton X-100 were mixed and 15 p1 used for discrete nebulization (in Chinese) Samples were heated with HNO at 105 "C. The time required for release of metals to give accurate results was investigated. Partial digestion by heating for 20 min followed by centrifugation was an effective procedure Binding to plasma ligands was investigated by SEC on Sephadex G-150.Changes in the first weeks of life were monitored extraction into CHC1,-n-hexane-CH,OH and formation of Cu soaps (in Chinese) Free fatty acids were measured indirectly by See Al ref. 94/C2021 Non-caeruloplasmin-bound Cu was extracted as the APDC complex into IBMK (in Spanish) See Ca ref. 9412173 In an investigation of age and gender on adult reference ranges samples were prepared for measurement by dilution with H 2 0 A novel FI procedure was assembled to take blood directly from the vein of an individual mix it with anticoagulant and acid. The FI stream passed through a microwave oven to the nebulizer for measurement. Matrix matched standards were prepared with human albumin and glycerol Solid material was broken down to fragments of 1-4 mg and placed into the graphite furnace through a 4 mm sampling hole.Measurements were made at a wavelength of 327.4 nm A Nafion-modified electrode was electrolytically coated with Cu" for a fixed time from a Cu solution. The Cu concentration in the solution was then measured. Nitrocaphamum was added to the Cu solution and the process repeated. The drug exchanged with Cu on the electrode to reduce the amount plated and the measurement of Cu gave an indirect method for the determination of this anticancer drug (in Chinese) See Cd ref. 94/28 11 Urinary excretion was increased with a reduction in serum concentrations during treatment for cancers with Pt drugs analysis from 0.8 ml sample at a sampling frequency of 100 h-' Dy-containing contrast medium were diluted 10-fold with 1 mol 1-' HCl and nebulized into an optimized ICP.The LOD was 24 ng mi-' were investigated An FI system was designed that provided triplicate Samples collected from monkeys gwen a Interferences in the analysis of digested specimens See Cu ref. 941778 Reference 94f697 c u Biological materials urine AA;F;L c u Liver AA;F;L 941727 941778 c u Tissues serum AA;F;L 9418 14 c u Tissue c u Liver AE;MIP;Sl AA;F air-C,H,;L 941 10 10 9411038 9411046 9411727 9411 101 9411232 c u Serum AA;F;L c u Blood plasma blood cells AA,ETAL c u Blood AA,F air-C,H,;L c u Tissues AE;ICP;L AA;F; L AA;ETA;L 9411 6 18 9411696 c u Plasma AA;-;L c u Biological materials AA;F;L 9411 75 5 c u Algal biomass c u Serum 94/c202 1 9412 1 2 1 9412173 9412246 c u Serum c u Plasma AA;-;- AA,F;L 9412248 c u Blood AA,F;L c u Animal feeds c u Nitrocaphamum AA;ETA;S AA;F;L A A; ETA L 9412402 9412800 94/28 1 1 94/c3 120 94lC3378 9413 164 94/21 11 941778 c u Urine c u Serum urine MS;ICP;L AA;F air-C2H,;L c u Serum AA;F;L AE;ICP;L DY Serum Eu Biological materials Fe Liver AE;ICPL AA;F;L Journal of Analytical Atomic Spectrometry April 1995 Vol.10 83RTable I (continued) Technique; atomization; analyte form* AA;F;L AE;MIP;Sl AE;ICP;L AA;F;L LMMS;-;S AA;ETAL AA;-;- Element Matrix Fe Tissues serum Fe Tissue Fe Tissues Fe Tissues Sample treatment/comments Reference See Cu ref. 941814 See Cd ref. 9411010 See Al ref. 94/1416 See Cu ref. 94/1618 9418 14 94/1010 94/ 1416 9411 6 18 Fe Clinical specimens A review of methods for the determination of Fe in Haem Fe and inorganic Fe were extracted from 9411655 9411709 human samples (in Spanish) proteins into IBMK.The two forms were then separated when the organic layer was mixed with 1% HCl; haem Fe remained in the IBMK while inorganic Fe was in the HC1. Samples were aspirated by discrete nebulization and Zeeman- effect background correction was used (in Japanese) Techniques to successfully isolate Fe isotopes for measurement by FAB-MS were discussed The biopsy sample was heated in a sealed container with HNO,-H,O for 60 s in a microwave oven and Fe measured in the clear solution. Normal values were 3-32 pmol 1-' while in haemochromatosis results were 79-690 pmol 1- HNO,-0.1% Triton X-100. The sample and Pd chemical modifier were injected into the graphite furnace (in Chinese) and sulfates was eliminated with a chemical modifier which contained NH,NO,-Ba(NO,),-Pd( NO3) AAS in toxicology Serum was diluted 5-fold with 10 mmol 1-' 9413 157 Interference due to high concentrations of Na salts 94/c34 12 Methods were presented in a series of applications of 941804 See As ref.941877 941877 Samples of otter liver were solubilized in 9411045 HNO,-HClO (4+ 1) at room temperature for 36-48 h. The solutions were taken to 4°C for 1 h to 140°C for 60-90 min cooled and the Hg measured Br-Br03 - reagent rapidly disrupted organomercury compounds to give the Hg" ions. An FI system was used for reduction and generation of atomic vapour 9411610 ,See As ref. 9411661 IConcentrations of Hg in hair teeth and blood correlated well with exposure to Hg vapour 4 highly sensitive system with an LOD below 0.5 pg 1-' was developed (in German) Factors influencing release of Hg vapour were studied in uivo and in vitro ;Specimens were digested with HNO,-H,O in a microwave oven (in German) Organomercury compounds were extracted from acidified samples into toluene for a preliminary cleanup by SEC.Compounds were separated by capillary GC See As ref. 94/2134 AA;F;L Fe Liver Fe Fe Biological materials Liver biopsy MS;-;S AA;F;L 9412 5 3 2 94/c3 1 2 1 Ge Serum AA;ETA;L Ge Biological materials AA;ETAL Plasma hair AA;ETA;L Urine Liver AA;CV;L AA;CV;L AA;CV;L Urine Urine AA;CV;L Blood hair tissues AA;CV;L 941 166 1 9411746 Urine AA;CV;L 9411 767 Dental amalgam saliva AA;CV;L Blood saliva urine AA;CV;L urine 9411 8 13 9411838 Tissues AE;-;L 94/C1965 Chinese patent medicines AAi-i- XRF; -;S Blood urine AA;CV;L 9412 134 9412 187 Comparable results were obtained when either conventional or microwave heating was used to digest samples in sealed digestion bombs ,4 gold-coated graphite furnace was use to trap the Hg vapour followed by thermal desorption (in Chinese) Sulfydryl groups in ovalbumin were determined by conversion to a mercaptide derivative separation from the matrix by HPLC and detection of the Hg species.Five organomercury compounds were investigated and ethylmercuric chloride was the most effective source for mercaptide formation Samples with HNO3-H2SO4-HC1O were left overnight and then heated at 105-120°C for 2 h. The solution was reduced with SnC1 for generation of the Hg vapour (in Chinese) Biological materials AA;CV;L 941241 1 Ovalbumin MS;ICP;L 9412533 Chinese medicines A A;CV;L 9412626 84 R Journal of Analytical Atomic Spectrometry April 1995 Vol.10Table 1 (continued) Technique; atomization; Element Matrix analyte form* Hg Tissues AE;MIP;L Reference 9412927 Sample treatmentlcomments DDC complexes of methylmercury and Hg" were extracted into toluene butylated wih a Grignard reagent and separated by GC using an MIP for detection by AE Methylmercury and Hg" were separately measured. 9412928 Hair AACV;L Methylmercury was extracted by shaking 90-125 mg hair with 2 mol I-' HC1 for 4 h. Hg" in the extract and in the dried solid phase was measured in a specific Hg analyser Hair was digested with HNO in a sealed pyrex ampoule at 50°C for 24 h.The solution was taken for reduction and vapour generation trapping on a gold-platinum grid and desorption at 700 "C. Conditions for the different steps were optimized and the performance of the overall method was characterized Increased concentrations were found in specimens from residents of an Amazonian region where Hg was used for extraction of Au Four digestion procedures were investigated and use of HNO3-H2SO4 was preferred with good recoveries of inorganic and organic forms of Hg Blood (0.5 ml) 1.2% Triton X-100 (0.5 ml) and H20 (4 ml) were mixed with 0.6 ml 8% KBr-1.2%0 KBr0 and taken to an FI manifold. The sample was streamed through a microwave oven mixed with KMnO and reduced by NaBH Hair AA;CV;L 9412965 Blood urine hair Tissues Blood AA;CV;L AA;CV;L AA;CV;L 94/c3 9413 9413 19 30 42 Chinese medicines AA;CV;L A mixture of HN03-H2S0,-H202 was'added to a 941c3404 medicine for digestion and the Hg" reduced with Sn(Cl),.Medicines were found to contain more than 0.5 ppm Hg prepared with dilute HNO or with NH solution spectroscopy (ICLS). 10 pI solution inside a sealed glass or quartz cell were heated to produce sample vapour. Radiation at 430-700 nm from a pumped dye laser was arranged so that the sample cell was in the laser cavity. Appearance of the vapour produced a change in the radiation intensity proportional to the analyte concentration. A graphite atomizer was also used to produce sample vapour Tissues were digested with acid and the ion-pair between InC1,2- and methyltricapryl ammonium ion extracted into hexane-IBMK.The In was back-extracted into HN0,-CH,COOH and measured in the aqueous layer. The assay had a sensitivity of < 1 ng ml-' Red cells were washed with isotonic LiNO and lysed by dilution 1 25 with 10 mmol I-' HCI The residues from digested specimens were diluted with 50 ml of 5 mg ml-' thiourea. 1 pl was injected into a molybdenum-atomizer Similar results were obtained when samples were Samples were analysed by intracavity laser 9412554 See Ca ref. 9412505 See Ca ref. 9411843 A 20 pl volume of sample placed onto a platinum loop was dried electrically and the loop positioned directly into the flame for analyte atomization. Salts remained on the loop so that spectral interferences associated with CaOH and SrO band emissions were not observed HN03-HC104 for 6 min and diluted with La3+ solution (in Chinese) Cell membranes in buffer were boiled with See K ref 941777 A Ficoll density gradient was used to isolate mononuclear cells from other blood components.The cells were lysed by addition of a detergent diluted with La solution and the Mg measured See Ca ref. 94/1351 9411 3 5 1 See Ca ref. 9411843 9411843 See Ca ref. 9412173 9412 173 See Ca ref. 9412245 94 f 2245 See Cu ref. 941C3120 94/c3 120 Serum Urine MS;ICP;L AA;-;L 9412929 941985 In Blood urine tissues A A;ETA;L K Erythrocytes AA;F;L 941777 K Biological materials AA;ETA;L 9412299 9412505 94/1843 9413 122 K Li Li Biological materials XRF;-;S Blood erythrocytes plasma AA;F;L Serum urine AE;F air-C2H2;L Erythrocyte membranes AA;F;L 941666 Erythrocytes Mononuclear leucocytes AA;F;L AA;F;L 941777 941983 Plasma MS;TI;S Blood erythrocytes plasma AAF;L Serum urine AA;F;L Serum urine AA;F air-C2H2;L Serum AA;-;- Journal of Analytical Atomic Spectrometry April 1995 Vol.10 85RTable 1 (continued) Technique; atomization; analyte form* AA;F;L AA;F air-C,H,;L Element Matrix Mn Liver Mn Hair Sample treatment/comments Reference See Cu ref. 941778 941778 A slotted quartz tube was used to increase sensitivity. 941851 Interferences from Ca Cr and Mg were reported (in Chinese) optimized for analysis of serum diluted 1 + 2 with 1 moll-' HNO (in Chinese) Power gas flow and observation height were 9411075 See Cu ref. 9411618 9411618 AE;ICP;L Mn Serum Mn Tissues Mn Blood urine AE1CP;L AA;F;L A A;ETA; L AA,ETA,L A 1 + 1 dilution of the sample with 0.2% Mg(NO,) was made and 20 p1 used for measurement.The LOD was reported as 0.08 pg 1-' with recoveries of approximately 96%. The same method was also published in Spanish and Portuguese (see refs. 9412116 and 9412117) 9411682 See Cr ref. 9411702 A complex between biotin and tricarbonylcyclopentadienylmanganese was used to label secondary antibodies included in an immunoassay for the measurement of bovine serum albumin See Ca ref. 9412505 An FI protocol involving solvent extraction preconcentration and AAS was presented (in Chinese) receiving Mn-rich total parenteral nutrition fluids microwave heated at 500 W for 3 min and diluted to 20 ml. Mo was then measured with BaF as chemical modifier from a platform coated with La(N03) (in Chinese) High concentrations were reported in patients 5 g sample with 2 ml HN03-6 ml H20 was See Cr ref.9411710 l'icric acid was added to a suspension of the sample in H20 and the Mo extracted with ethylphenylcyclohexanecarboxylic acid in CHCl "Mo and lwMo were measured in bioavailabilty studies (in German) Gastrointestinal absorption of Mo was determined using '"OM0 as the tracer (in German) HNO,-HCI (2 + l) 4 ml with 200 mg sample was heated in a microwave oven taken to pH 3 and diluted to 100 ml. To 50 ml 1 ml of 1 mol 1-' NaClO and 5 ml pH 3 glycine buffer were added for extraction with 0.1 % 1,5-bis-(di-2-pyridyl- methylene) thiocarbonohydrazide in IBMK lJrine measurements were used to monitor occupational exposure to Ni The bacterium Thiothrix strain Al was added to the sample solution.After an incubation period the cells were isolated digested and metals measured. Ability of the cells to adsorb metals was related to factors such as age incubation time and the content of the medium on which the bacterium was cultured. See As ref. 9411281 9411281 The various steps involved in GC-MS measurement 941 1325 Serum was diluted 1 + 1 with 1% HNO,-0.25% 9412954 of Ni were discussed Triton X-100. Aqueous standards were similarly prepared in a method that showed good precision and accuracy See Cr ref. 9413258 9413258 A computer program for a proficiency testing scheme 941650 was described with Pb in blood as the model. The program allowed data handling presentation of results and evaiuation of performance. A procedure with HNO3-HC10 was the most effective of three digestion methods investigated.Inclusion of H2S04 caused suppression of atomization but improved sensitivity was seen with the addition of ascorbic acid Pb in urine diluted 2-12.5-fold with 1% HNO was atomized from a graphite probe. Chemical interferences were not seen and calibration was with aqueous solutions 941686 Mn Mn Biological materials Immunoglobulins 9411702 9412257 _ * _ * _ > > AA;ETA;L Mn Mn Biological materials Hair Chinese medicines XRF;-;S AA;F;L 9412505 9412 8 9 5 Mn Mo Blood Liver AA;ETA;L A A;ETA; L 94lC3116 941678 Mo Mo Pharmaceuticals Tissues AA;ETA;L AA;-;L 9411710 9412095 MS;ICP;L Mo Mo Ni Faeces urine 9412650 9413 192 941685 Urine faeces Tissues MS;ICP;L AA;ETA;L AE;ICPL Ni Ni Urine Bacteria AA;ETA;L AA;-;L 941767 941784 Ni Ni Urine Semen urine MS;ICP;L MS;GC;L AA;ETA:L Ni Serum Ni Pb Urine Blood Biological materials AA;ETA;L Pb Pb Urine AA;ETAL 9417 12 86 R Journal of Analytical Atomic Spectrometry April 1995 Val.10Table 1 (continued) Technique; atomization; Element Matrix analyte form* Pb Blood AA;ETA,L Pb Urine AA;ETA;L Pb Bone AA;ETA;L Sample treatmentjcomments See Cd ref. 941798 See Cd ref. 941799 10-20 mg bone was dissolved at room temperature in HNO,. This solution was analysed with Pd(NO,),. Calibration by standard additions was essential to obtain accurate results and environmental specimens in a study to identify sources of exposure among a population with high total blood Pb levels Pb in blood and in acid digested-synovial fluid was extracted as the APDC complex into IBMK.Concentrations in blood and synovial fluid were not correlated (also see ref. 941834) The 206Pb 207Pb ratios were determined in blood See As ref. 9411 188 Accurate results were obtained for CRMs diluted 1 + 4 with 1% Triton X-100 and assayed with either 1% (NH,),HPO or 1% (NH,),HPO,-0. 1 YO PdCI (in Korean) See Cd ref. 94jC1984 In vivo measurements of Pb were made in different bones of individuals with current and previous occupational exposure to Pb See Cd ref. 9412345 Organolead compounds were separated by LC coupled to an LEI flame for detection and measurement in the eluent Exposure to Pb among populations living close to a factory were assessed by in viuo measurement in bone. Concentrations were three times those of control subjects (NH,),HPO,-Triton X-100 was suitable for measurement of Pb at concentrations of 0.25-6 pmol 1-' Pb-APDC complex into butyl acetate N. American adults was established An Australian standard method with blood diluted in An Australian standard method with extraction of a A reference range of less than 100 pg 1-' for healthy See Bi ref.9412614 In studies of dermal absorption of Pb ICP-MS was preferred due to simple sample preparation although better precision and accuracy was obtained with TIMS See Cd ref. 941281 1 A preliminary partial digestion step with addition of HNO to blood and heating at 120°C was followed by dilution with 1 % ( NH,),HP04-0.2% HNO,. A portion of this solution was injected into the graphite furnace.Calibration solutions were prepared in the diluent solution The Li-bis( trifluoroethy1)dithiocarbamate chelate with Pt was formed and measured by GC-MS. Results compared well with those obtained by AAS for urine but there were significant differences with other biological fluids Cisplatin and its metabolites were separated by reversed-phase ion pairing LC with ICP-MS detection Digested samples were electrochemically deposited onto an electrode constructed of reticulated vitreous carbon packed within a graphite furnace. The furnace was then placed into the spectrometer so that the light beam passed along a hole drilled through the vitreous carbon. The LOD was 0.3 ng Pt Distribution and excretion of Pt was determined following administration by perfusion of the pulmonary blood supply was determined. Therapeutic response was positively associated with adduct formation Binding of platinum anticancer drugs to nucleic acids Reference 941798 941799 941807 Pb Blood Pb Blood synovial fluid MS;ICP;L AA;ETAL 941984 AA;-;L 9411031 Pb Urine Pb Blood AA;ETA;L AA;ETA;L 9411 188 9411667 Pb Pb Blood Bone AA;ETAL XRF;-;S 94/c 1984 9412306 Pb Pb Blood Biological materials MS;ICPL LE1;FL 9412345 9412394 Pb Bone XRF;-;S 9412496 Pb Blood AA; ETkL 9412602 Pb Blood AA;F air-C2H,;L 9412603 Pb Blood MS;ICPL 94/26 1 3 Pb Pb Plasma urine Clinical fluids MS;ICPL MS;ICPL MS;-;S 94/26 1 4 9412795 Pb Pb Urine Blood M S;IC P; L AA;ETA;L 94/28 1 1 94/c3407 Pt Urine plasma ultrafiltrate AA;ETA;L MS;GC;L 941769 Pt Pt Biological fluids Biological materials MS;ICP;L 94/ 941 407 643 AAETA;L Pt Pt Tissues plasma urine AA;ETA;L Tissues AAETA;L 94/ 1 720 9411743 Journal of Analytical Atomic Spectrometry April 1995 VoZ.10 87RTable 1 (continued) Technique; atomization; analyte form* Element Matrix Reference 94/844 Sample treatment/comments ,Qnalytical conditions were investigated. Use of a L'vov platform pyrocoated graphite tubes and 20 pg Ni as the chemical modifier were recommended. NaCl was added to standard solutions. A sensitivity of 0.0067 pg ml-l was reported (in Chinese) See As ref. 9411700 Possible chemical modifiers for the thermostabilization of Sb were investigated and a mixture of Pd Pt Rh and Ru each at 0.025% with 1% ascorbic acid was the most suitable. Samples were diluted 1 + 3 in 0.1% Triton X-100 See As ref.941637. The atomizer was operated at 750 "C and recovery of 10-50 ng Se(1V) was 95-1 10% 0.01 mol 1-' Br in 48% HBr at 122 "C released Se from selenomethionine selenocysteine and selenopurine. With this procedure accurate results were obtained for CRMs See Hg ref. 941804 Samples were diluted 1 +9 with 0.2% HNO and 10 pl placed into the furnace. The chemical modifier was 10 pl containing for serum 0.3 pg Pd 30 pg Ni 80 pg NH,NO3 in 0.04Y0Triton X-100-0.2% HNO, for urine 0.6 pg Pd 25 pg Ni 80 pg NH4N03 in 0.2% HNO,. Standard additions calibration was employed Suspensions of membranes from patients with hypertension and coronary disease were digested with HN03-HC10,-H,S0,. The residue was heated with HCl and KBH solution added for HG. An LOD of 0.7 ng Se was obtained (in Chinese) See As ref.94/1294 44 unified on-line system was developed for digestion of the sample with H,SO,-HClO,-HNO at 240°C in an ultrasonic field reduction to SeH,; and transfer to the plasma. The LOD was 5 pg 1-' Samples were diluted with Triton X-100 and Pd was used as the chemical modifier See As ref. 9411700 See Cr ref. 9411702 See Cr ref. 94/1710 Conditions for acid treatment with microwave heating which would either preserve or breakdown organoselenium species were investigated Samples were digested with HN03-HC104 at 95 "C and the metalloid reduced by 6 mol 1-' HC1. The hydride was formed by addition of 2% m/v NaBH and trapped at > 200 "C onto a graphite furnace coated with AgNO,. Atomization was accomplished by heating to 1800°C and the characteristic concentration was 17 pg Differences in thermostability of Se" Sev' selenomethionine and trimethyselonium were systematically determined with series of chemical modifiers.The recommended modifier was 7.5 pg Pd-5 Pg Mg(NO,) See As ref. 94/2951 See As ref 9412973 The vaporization temperature of Se was increased by Pd or Rh. In the presence of oxidizing agents however the Se was extremely refractory with a vaporization temperature > SO00 "C. Addition of reducing agent or an increase in the amount of Pd or Rh attenuated this negative interference (in Japanese) A method with good accuracy precision and recovery was set up with Pd(NO,) and Triton X-100 chemical modifiers. Zeeman-effect background correction eliminated interference from Fe and phosphate heated in a microwave oven.Selenomethionine was completely broken down with HNO,-H,O as the digestion material Specimens were digested in sealed PTFE vessels Sb Urine AA;ETA;L Sb Sb Hair nails Blood urine AA;H y ;L AA;ETA,L 94/1700 9412209 Biological materials Serum urine A A;H y ;L AF;H y;L Se Se 94/637 94/742 Se Se Plasma hair Serum urine AA;ETA;L AA;ETA;L 94/804 941861 Se Erythrocyte membrane AF;Hg;L 9411233 Se Se Serum urine Serum MS;ICP;L AE;ICP;L 9411294 94/1645 Se Blood AAETA;L 94/1685 Se Se Se Se Hair nails Biological materials Pharmaceuticals Tissues 9411700 9411702 94/1710 941C1890 Se Biological materials AA;Hy ;L 94/2185 Se Serum urine AA;ETA;L 94/2 186 Se Se Se Blood Biological materials Urine LEAF;-;L MS;ICP;L AA;ETA;L 941295 1 94/2973 9413311 Se Serum AA;ETA;L 94/C 3402 Se Hair nails AA;ETA;L 94JC3439 88 R Journal of Analytical Atomic Spectrometry April 1995 Vd.10Table 1 (continued) Technique; atomization; analyte form* Element Se Si Si Matrix Urine Sample treatmentlcomments trimethylselonium ion was proposed with an FI procedure for subsequent HG and measurement of the Se with HNO at 90"C an La-Ca mixture was added and Si atomized from pyrolytically coated tubes. Disodium tartaric acid (for bone) and NH4H2P04 (for soft tissues) were used as chemical modifiers platforms and tubes for the determination of Si was investigated. Chemical modifiers were also studied. It was found that best performance was obtained with tungsten coatings and that no modifier was necessary. Si was determined in serum and urine after 1 + 3 and 1 + 49 dilution in H,O respectively Acidified Br-BrO,- to break down The samples were taken into solution by heating The use of Mo Ta W and Zr to treat graphite See Al ref.9412924 also see Si ref. 9412211 Si was extracted from 7.5 mg dried tissue with heptane for measurement in a system using a 300 W Xe arc lamp continuum light source See Se ref. 94/C1890 The chemical modifier was KNO and recovery was The effect of Sn" on the HPLC separation and An FI manifold was designed to load 10.7 ml 95.8-101% (in Chinese) recovery of organotin compounds was investigated acidified sample onto an ion-exchange column and elute the Sn with 0.05 mol 1-1 HNO into an apparatus for HG. The gaseous hydride was transferred to a palladium-coated graphite tube at 300 "C for retention followed by heating to 2300°C for atomization The LOD was 0.05 pg 1-I Solutions from hair digested with HN03-H202 in a sealed vessel at 130°C for 30 min were mixed with EDTA to remove interferences from Ca and Mg (in Chinese) See Mn ref.9411075 See Ge ref. 9413157 See As ref. 9411700 See Se ref. 9412185 Particulate material from titanium implants was detected within bone (in German) A method was presented with Pd and Mg(NO,) as chemical modifiers in a series of applications of AAS in toxicology See Bi ref. 9412614 See As ref. 9411281 See Cr ref. 9411702 See Cr ref. 9412879 See As ref. 9412973 See Cr ref. 9413258 See Cu ref. 941778 See Ni ref. 941784 See Cu ref. 941814 See Cd ref. 94/1010 See Cr ref. 94/1101 See Cu ref. 9411232 After preliminary ion-exchange chromatography Zn isotope ratios were measured.Similar results were given by both techniques See Cu ref. 94/1618 Reference 94/C347 1 94/22 1 1 9412400 9412924 9413300 94/C 1890 94/24 10 9412689 94/c33 77 9411073 9411075 9413 157 9411 700 94/21 85 941829 941801 9412614 9411281 9411702 9412879 9412973 9413258 941778 941784 9418 14 941 101 0 9411 101 9411232 9411352 94,4618 9411696 9412173 9412248 9412543 9412908 9412944 94/c3120 AA;Hy;L Bone tissues A A;ETA;L Serum urine AA;ETA;L Si Si Serum Breast tissue AA;ETAL AA;ETAL Sn Sn Tissues Blood Sn Tissues MS;ICP;L Sn Serum AA;Hy;L Sr Hair AA;F air-C,H,;L Sr Sr Te Te Ti Serum Serum Hair nails Biological materials Bone AE;ICP;L AA;ETA;L AA;Hy;L AA;Hy;L AE;ICP;L T1 Urine AA;ETA;L T1 V V V V V Zn Zn Zn Zn Zn Zn Zn Plasma urine Urine Biologcal materials Urine Biological materials Urine Liver Bacteria Tissues serum Tissue Blood plasma blood cells Blood Blood faeces breast milk MS;ICP;L MS;ICPL - a _ * _ M ~ ; I ~ P ; L MS;ICPL MS;ICPL AA;F;L AA,F;L AE;MIP;Sl A A;ETA,L AA,F air-C,H,;L M S;ICP;L AA;-;L MS;FAB;- Zn Tissues AE;ICP;L AA;F;L AA;ETA;L AA;-;L AA;-;- AA;F;L MS;ICP;L AE;ICP;L MS;ICP;L Zn Zn Zn Zn Zn Plasma Serum Blood Biological materials Milk urine See Cu ref.9411696 See Ca ref. 9412173 See Cu ref. 9412248 See Ca ref. 9412543 Zn isotopes were separated from C1 Na and other possible sources of MS spectral interference by chelation onto carboxymethylated pol y (eth y1eneimine)-poly (me t hylenepolyphen ylene) isocyanate resin See Cd ref. 9412944 See Cu ref.94/C3120 Zn Zn Blood tissues Serum urine MS;ICP;L AA;F air-C,H,;L Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 89RTable 1 (continued) Technique; atomization; Element Matrix analyte form* MULTI-ELEMENT ANALYSIS Serum plasma and blood Various (22) Blood serum urine A A;ETA; L Various ( 5 ) Erythrocytes plasma AA;-;- Various (8) Blood AA;ETA;L Various ( 5 ) Serum Various ( 5 ) Blood urine Various (11) Serum Various Blood tissues urine Various Biological fluids tissues Various (5) Serum Various Blood urine MULTI-ELEMENT ANALYSIS Urine Various (22) Blood serum urine Various ( 5 ) Blood urine Various Blood tissues urine Various Tissues urine milk Various Biological fluids tissues Various Biological fluids Various (8) Urine Various Blood urine XRF;-;S AA;ETA;L MS;ICP;L AA;ETA;L MS;ICP;L AA;ETA;L MS-1CP;L AA,ETA;L AAETA;L AA;-;- MS; _ _ 3 AE;ICP;L AA;ETA;L AA;-;L MS;ICP;L A A;ETA; L MS;ICP;L Sample treatmenticomments Reference Reference values were reported for healthy subjects without occupational exposure Children with congenital biliary atresia had altered concentrations compared with their controls (Cu Fe Mg Se Zn) (in Japanese) Blood was diluted 1 + 3 and Pd-ascorbate added; the modifier included potassium persulfate for measurement of As.Calibration was by standard additions (Al As Cd Cr Mn Mo Ni Se) (in Japanese) Specimens were digested with HNO Ga added as an internal standard and a 20 pl aliquot dried onto the sample carrier (Cu Fe Rb Se Zn) Conditions for simultaneous multi-element measurements were established (As Cd Pb Se Zn) containing Be In and T1 as internal standards the samples were aspirated into a carefully optimized system.Memory effects were removed with a 2 min wash phase and the LODs were from 0.007 ng ml-' (Bi) to 0.5 ng ml-' (B) (B Ba Bi Cd Cs Hg Li Mo Pb Sb Sn) ,9 review which discussed the importance of trace elements to human health in terms of essential nutrients and as toxic agents. Approaches to their measurement in clinical specimens were described More than 50 elements have been measured in occupational and environmental health practice. ETAAS is appropriate for many of these and practical aspects of the analyses were reported in this review The samples were diluted 4-fold or 8-fold with 0.14 moll-' HNO containing Co and In as internal standards and measurement were made with a new high resolution ICP mass spectrometer.Spectral interferences typical of quadrupole MS were not observed and accurate results were obtained for a serum RM (Ag Cu Fe V Zn) Applications of ETAAS and ICP-MS to clinical problems were presented 4fter 1 +4 dilution with 0.14 mol I-' HNO Reference values were reported for healthy subjects Conditions for simultaneous multi-element without occupational exposure measurements were established (As Cd Pb Se Zn) A review which discussed the importance of trace elements to human health in terms of essential nutrients and as toxic agents. Approaches to their measurement in clinical specimens were described investigated. Combinations of HNO H$04 and HzOz power-time settings and other factors were optimized Adore than 50 elements have been measured in occupational and environmental health practice.ETAAS is appropriate for many of these and practical aspects of the analyses were reported in this review Formation of micelles and vesicles by addition of surfactant was developed and the advantages which these structures offer to analytical procedures were investigated. Improvements in nebulization and atomization efficiencies graphite wettability generation of volatile species and other examples were demonstrated with short analysis times (in German) (As Cd Co Cu Mn Pb T1 Zn) problems were presented A focused open microwave digestion system was Good results were achieved with both techniques Applications of ETAAS and ICP-MS to clinical 94/1681 9411703 9411705 94/1728 94/C1947 94/2213 94/2244 9412946 9413277 94lC3418 9411681 94/C 1947 9412244 9412556 9412946 9413036 9413191 94jC3418 90 R Journal of Analytical Atomic Spectrometry April 1995 Vol.10Table 1 (continued) Technique; atomization; Element Matrix analyte form* MULTI-ELEMENT ANALYSIS Other biological fluids Various (5) Various Various (6) Various (5) Various (10) Various Various Various (6) Various Dialysis fluids Biological fluids Dialysis solutions Breast milk Breast milk Total parenteral nutrition fluids Tissues urine milk Breast milk Biological fluids MULTI-ELEMENT ANALYSIS Soft tissues Various (7) Hair tissues Various Normal and malignant cells Various Lung Various (8) Liver kidney Various (22) Brain cells Various (19) Brain Various Blood tissues urine Various Liver cell Various Tissues urine milk Various (10) Liver AA;ETA;L SIMS;-;S AA;ETA;L AA;ETA;L AE;ICP;L XRF;-;S AE;ICP;L AE;ICP;L AA,-;- AEiICPi- XRF;-;S PIXE;-;S AE;ICP;L AA;ETA;L AA;F;L AA;HG,L AA;CV;L AA;ETA;L A A;ETA;L AE;ICP;L AA;-;- AE;F;L AE;ICP;L AA;-;- MS; _ - XRF;-;S AE;I C P; L XRF;-; S Sample treatment/comments Methods were presented in a series of applications of Procedures were developed to deposit nanolitre AAS in toxicology (Al Cd Co Cr Pb) volumes of sample for quantitative measurement of elements by SIMS Analytes were extracted and concentrated from the dialysis fluid salts by formation of APDC chelates and retention on columns of Amberlite ZAD-4 (Cd Co Cu Fe Ni Pb) chemical modifiers (e.g.Mg(NO,) Ni) (Cr Cu Fe Mn Se) during the first 5 months of lactation.There was no change in Ba Si or Sr. Al Li Mn and Ti were found in some samples parenteral nutrition was investigated by collection onto membrane filters investigated. Combinations of HNO H2S04 and H,O power-time settings and other factors were optimized 25% ethoxy nonylphenol was added to samples at a final concentration of 0.3% m/v to effect emulsification. A further 10-fold dilution with 1 % HNO was made and the samples were nebulized (Ca Cu Fe K Mn Zn) Formation of micelles and vesicles by addition of surfactant was developed and the advantages which these structures offer to analytical procedures were investigated. Improvements in nebulization and atomization efficiencies graphite wetability generation of volatile species and other examples were demonstrated Diluted samples were analysed with appropriate Concentrations of Cu Fe and Zn gradually fell Stability of trace elements in fluids for total A focused open microwave digestion system was In an international study samples were prepared by a common procedure to investigate any relationship between concentrations in hair and tissues (As Cd Cu Hg Pb Se Zn) PIXE analysis was used to determine the intracellular distribution of trace elements Ashed samples were dissolved in 1 ml HNO and diluted to 25 ml.Li and Pb were determined by AAS other elements by AES in a study of normal values in non-smokers An automated digestion procedure was employed for preparation of samples from muskoxen (As Cd Cu Hg Mn Pb Se Zn) chromatin by the action of micrococcal nuclease.Samples from patients with Alzheimer’s disease had increased A1 and reduced Mg compared with control material Different brain regions were examined to investigate compositional changes with aging (in Japanese) A review which discussed the importance of trace elements to human health in terms of essential nutrients and as toxic agents. Approaches to their measurement in clinical specimens were described Examination of element distributions within a single cell was discussed with reference to micro-PIXE and SR-XRF techniques investigated. Combinations of HNO H2S04 and H,O power-time settings and other factors were optimized SR-XRF was applied to the analysis of a CRM (Br Ca C1 Cu Fe K Mn P S Zn) (in Chinese) Nuclear material was prepared from cellular A focused open microwave digestion system was Reference 941801 9411541 9411665 9411679 9411867 94/23 10 9412556 9412909 9413036 941676 941905 9411 105 9411242 9411657 94/17 12 9412244 941238 1 9412556 9412569 Journal of Analytical Atomic Spectrometry April 1995 Vol.10 91 RTable 1 (continued) Technique; atomization; Element Matrix analyte form* Various Biological fluids tissues A A; ETA;L MULTI-ELEMENT ANALYSIS Bone and other hard tissues Various (5) Renal stones PIXE-;S Various Bone XRF;-;S Various (16) Bone AA;ETA;L Various Calcified biological materials MS;ICP;S AE;ICP;L MULTI-ELEMENT ANALYSIS Hair nails Various (7) Hair tissues XRF;-;S Various (14) Hair AESpark;L Various (15) Toe nails hair Various (5) Hair Various (6) Hair Various (9) Hair Various Hair AA;F;L AA;ETA;L XRF;-;S AA;F;L MS;ICP;L XRF;-;S MULTI-ELEMENT ANALYSIS Biological materials RMs Various Biological materials AA;ETA;Sl Various ( 11) Biological materials Various Biological materials Various Biological CRMs Various Medicinal plants AE;ICP;L AE;MIP;L _*_.- 9 AE;ICP;L Sample treatmen tjcommen ts More than 50 elements have been measured in occupational and environmental health practice.ETAAS is appropriate for many of these and practical aspects of the analyses were reported in this review 'The matrix composition of samples was determined by FTIR and by proton elastic back-scattering spectrometry so that appropriate corrections could be made in PIXE analyses (Br Cu Fe Sr Zn) Capillary focused XRF provided a very detailed map of the elemental distribution within bone samples Bone biopsy specimens from patients undergoing haemodialysis were analysed after acid digestion Qualitative distribution patterns of elements across structures such as teeth shells scales etc.were mapped by LA-ICP-MS In an international study samples were prepared by a common procedure to investigate any relationship between concentrations in hair and tissues (As Cd Cu Hg Pb Se Zn) Washed sample 0.5 g was heated to 510°C and the ash mixed with 10 mg Si0,-NH41-Na2S04-C (5 40 10 145) with heating by IR. A drop of 50% ethanol containing 5% cane sugar and 50% NHJ was added and the sample dried for vertical electrode AES (in Chinese) Specimens solubilized with tetraalkylammonium hydroxide for 30 min at 90°C were analysed by pulse nebulization FAAS with a slotted quartz tube or by ETAAS.Matrix matched calibration solutions were prepared 'The distribution profiles along single hair specimens were examined in samples from 11 pregnant women (Ca C1 Cu Fe Zn) (in Chinese) Clean dry hair was dissolved in HN03-H202 HC104 added and the solution heated almost to dryness. The residue was diluted with H 2 0 and analysed by pulse nebulization (Ca Cu Fe Mg Mn Zn) (in Chinese) Short (mm) lengths of a hair strand were dissolved at room temperature in HNOJ diluted with H20 and 50 pl sampled by FI into the ICP (Al As Cd Cu Hg Pb Se T1 Zn) resolution and sensitivity was used to demonstrate the cross-sectional distribution of elements in a single hair A synchrotron X-ray microprobe with high PTFE beads were used to prepare finely ground particles and H,O or 5% HNO slurries were maintained by ultrasonic mixing.The importance of factors such as particle size and density addition of Triton X-100 and ultrasonic power were discussed Flow rates pH and eluents were investigated to determine the optimum conditions for on-line preconcentration onto an oxine microcolumn coupled to an ICP spectrometer Poor results were obtained for Cr and Fe with a helium-MIP for detection by AES environmental RMs HNO and HC104 at 160°C in a sealed container for 4 h. The sample was evaporated to dryness and the residue redissolved in 50% v/v HN03 (in Chinese) Organometallic compounds were separated by GC An update to a regular compilation of biological and Dried powdered plant materials were heated with Reference 9412946 9411 119 9411570 9411686 9413263 941676 941836 941935 941 941 94/ 069 214 369 9411 599 941732 941736 941941 941979 94/1168 92R Journal of Analytical Atomic Spectrometry April 1995 Vol.10Table 1 (continued) Technique; atomization; analyte form* SIMS;-;S XRF;-;S Element Various Various Various (6) Various Various Various Various Various Various Various Various ( 5 ) Matrix Biological materials Sample treatment/comments Design of instrument performance characteristics and applications were presented in this review Sample collection storage and preparation for EDXRF were discussed with reference to problems which can arise Egg proteins were separated by diethylaminoethyl- Dextran (DEAE-cellulose) chromatography and the metal contents determined (Ca Cu Fe Mg Mn Zn) A review of new developments and trends in analytical techniques for trace element analyses A review of the use of plasmas with emphasis on clinical applications A review of recent instrumental developments involving these techniques with some discussion of important areas of application Application to biological specimens was discussed (in Japanese) A review of recent work in medicine nutrition and toxicology A ‘speciation analysis’ using a range of analytical techniques was presented (in Chinese) Possible spectral interferences from elements found in biological samples were documented and procedures to overcome such interferences were discussed (C Cay C1 K Na P S) The samples were digested with HN0,-HCl- HC104-HF in sealed containers in a microwave oven evaporated to dryness and the residue redissolved in 0.1 mol 1-1 HClO containing 100 ng g-’ Be as internal standard.An ultrasonic nebulizer was used for sample introduction (Cd Co Cu Ni Pb) He MIP-MS was developed to avoid some of the problems associated with Ar ICP-MS and the conditions for use were described A slurry of the sample with PTFE was prepared and placed into a graphite furnace for ETV-ICP-AES. The PTFE served as a fluorinating reagent to prevent the formation of refractory carbides and improve performance (B Cr Mo V REEs) Further work was described for reduction of the analysis time to 30-60 s per measurement TXRF was used to examine solid samples. Reference 9411 527 9411565 9411865 9412 109 9412 1 10 9412207 9412493 9412540 9412624 94/2905 9413133 9413269 94/C3372 Biological materials Silkworm eggs AA;F;L Biological materials Biological materials Biological materials Biological materials XRF;-;S Biological materials Chinese medicines Biological materials MS;ICP;L AA;-;- MS;ICPL AE;ICP;L Biological materials Various Biological materials Various Biological materials MS;MIP;L AE;ICP;Sl Various Biological materials AA;ETA;L 94/c3427 INDIRECT ANALYSIS Terfenadine Antihistamine drugs oxamine- HCl G1 ycine Pharmaceuticals chlorphen- AA;-;L AA;F;L Ternary complexes were formed between the antihistamine drugs thiocyanate and Co and extracted into C6H6.Measurement of Co provided for the indirect determination of the antihistamines Samples of pharmaceutical solutions were pumped through a polyester resin.Cu trapped within the resin was dissolved by glycine in the sample and measured in an indirect method for the determination of the glycine Free fatty acids were measured indirectly by extraction into CHC1,-n-hexane-CH,OH and formation of Cu soaps (in Chinese) 941772 94/697 Free fatty acids Biological materials Pharmaceutical preparations AA;F;L 94/1755 9412204 Alkaloids; paperavine strychnine cocaine AA;F air-C,H,;L An FI continuous precipitation and filtration system was developed for the indirect measurement of papaverine strychnine and cocaine. The alkaloids were mixed with a BiI,- reagent to give the ion pairs which precipitated from solution. The decrease in Bi was proportional to the concentration of alkaloid A complex between biotin and tricarbonylcyclopentadienylmanganese was used to label secondary antibodies included in an immunoassay for the measurement of bovine serum albumin.Determination of Mn provided the Bovine serum albumin Serum AA;ETA;L 9412257 data for quantification Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 93RTable 1 (continued) Element Matrix Sulfdryl Ovalbumin groups Nitro- Pharmaceutical solutions caphamum Technique; atomization; analyte form* Sample treatment/comments Reference Sulfydryl groups in ovalbumin were determined by 94/25 3 3 conversion to a mercaptide derivative separation from the matrix by HPLC and detection of the Hg species. Five organomercury compounds were investigated and ethylmercuric chloride was the most effective source for mercaptide formation A Nafion-modified electrode was electrolytically coated with Cu(I1) for a fixed time from a Cu solution.The Cu concentration in the solution was then measured. Nitrocaphamum was added to the Cu solution and the process repeated. The drug exchanged with Cu on the electrode to reduce the amount plated and the measurement of Cu gave an indirect method for the measurement of this anticancer drug (in Chinese) MS;ICP;L AA;ETA;L 94/2800 2. ANALYSIS OF FOODS AND BEVERAGES Simon Branch and Helen Crews A summary of the published and conference papers covered in this review is given in Table 2. There are some differences in the organization of this part of the review compared with last year (94/739). Primarily there are more sections dealing with the progress made for individual elements.This is similar to the format for the first part of this review and serves to highlight those elements which are receiving particular atten- tion in the literature. For example As Hg Se and Sn have high profiles this year and there are some interesting papers on Ba Cr Fe I and Sb. In addition to our 1993 ASU review (94/739) three papers have been published during the past year which address various aspects of food analysis and spectroscopy. A Japanese publication (94/8 19) reviews methods for toxic elements (As Cd Cr Hg Pb Se and other harmful elements). A large review (684 references 94/1054) has been published which reports the analytical methods used for foods and beverages in China during the period 1990-1991 and the use of spectroscopy in food science has been described in an English publication by Belton et al.(94/1252). 2.1. Sampling and Sample Preparation 2.1.1. Direct determination of analytes Particular attention was paid to the direct analysis of foods matrices in a review of the analysis of trace elements by ETAAS with Zeeman correction (94/1677). The use of simple dilution of the sample with adequate chemical modification when possible is discussed and also the potential for the routine use of Zeeman-effect ETAAS in the food industry. As might be expected the direct determination of analytes is most feasible in water samples and several authors report this type of study. Sixteen elements (Ag Al As Ba Be Cd Co Cr Cu Fe Mn Ni Pb Se V and Zn) were determined in 96 Italian mineral waters using ETAAS with Zeeman-effect back- ground correction (94/797).The results from inter-laboratory studies were used to compare the effectiveness of this method of measurement with that using deuterium background correc- tion. Both Be (94/856) and Zn (94/1165) have been measured in drinking waters. Ammonium phosphomolybdate and ascor- bic acid were used with ETAAS for Be determinations resulting in an LOD of 0.03 pg 1- ' . Zinc was measured by FAAS after sample evaporation to 10 ml. An ultrasonic nebulizer with aerosol desolvation was used to improve the determination of Ag Al B Ba Ca Cd Cr Cu Fe K Mg Mn Na Ni P Pb S and Zn in drinking water by ICP-OES (94/1247). The small droplet size produced by use of a plate vibrating at ultrasonic frequency produces better 94 R Journal of Analytical Atomic Spectrometry April 1995 transport efficiency than with pneumatic systems.This means that more sample is delivered to the plasma and sensitivity is improved. Desolvation reduces the water loading of the plasma and thus reduces potential interferences. The authors quoted 'excellent' agreement with certified values when they used this technique to analyse the NIST SRM 1643c Trace Elements in Drinking Water. Gooch (94/1081) used solvent extraction with FAAS to measure Si in fruit juices. Fresh lemon juice required neutraliz- ation with NaOH plus re-acidification with HCl and grape juice needed to be diluted with H 2 0 (1 + 1) prior to extraction with IMBK. Pineapple orange and bottled concentrated lemon juice could be extracted without sample pre-treatment.As little as 1 ppm Si could be measured by this procedure which was used to determine traces of Si from defoamer in the fruit juices. Human milk was measured by ETAAS after aqueous dilution and addition of Mg(N0,)2 and Ni chemical modifiers (94/1679). Chromium Cu Fe Mn and Se were determined. Miller-Ihli and Greene (94/2247) have devised a simple method for the direct determination of Pb in sugars by ETAAS. The method used Mg(NO,) as chemical modifier O2 ashing platform atomization and quantification using peak area measurements with aqueous standards. A char temperature of 750 "C provided efficient ashing whilst avoiding unnecessary oxidation of the graphite tube and platform. Sucrose solutions were prepared using equal masses of crystalline sucrose and 5% sub-boiling distilled HNO and analysed directly.High fructose corn syrups were also diluted with an equal mass of 5% sub-boiling distilled HNO to facilitate pipetting. The LOD for a 20 pl injection was 0.5 pg 1-' which corresponded to an LOD of approximately 0.9 ng Pb g-' for sucrose and high fructose corn syrup. The direct analyses compared favour- ably with a wet digestion procedure and had the advantages of reduced opportunities for contamination shorter analysis times and decreased chance of loss of analyte. Additionally less chemical waste is produced. 2.1.2. Preconcentration Flame AAS has been used for the determination of Cd Cu and Pb in drinking water after preconcentration by coprecipi- tation (94/2298). Water was shaken with aqueous 20% Mg(N03)2-20% NaOH (1 + 1) and left to stand for 1 h.The lower phase with precipitate was centrifuged and the residue dissolved in HNO (0.5 ml) and diluted to 10 ml with H,O. Cadmium Cu and Pb were determined using an air-C2H2 flame with corresponding LODs of 3.5 16.7 and 5 ng ml-'. Analyte recoveries ranged from 89 to 109% with RSDs from 3.0 to 6.4%. Concentration by adsorption onto a resin followed by elution Vol. 10prior to measurement by AAS has been reported by Tuker et al. (94/737) using Amberlite XAD-16 for the determination of Cu Ni and Zn in tap water and by Baralkiewicz et al. (94/1033) using an amidoxime resin for the determination of Cd Co Cu Ni Pb and Zn in tap or natural waters. In a conference presentation Shukun et al.(94/C3408) described an FI system for on-line adsorption preconcentration for FAAS determination of Cd in powdered rice and human hair CRMs. Cadmium complexed with NaDDC was sorbed onto the inner walls of a 'knotted' reactor coil and eluted on-line by IBMK. Thiourea and ascorbic acid-phenanthroline were used to overcome interferences from Cu and Fe respect- ively. At a sample loading rate of 5.2ml min-' the retention efficiency was about 8O% the enhancement factor was 66 with a preconcentration period of 50 s using 5 ml of sample. For a sampling frequency of 55 samples h-' the LOD was 0.1 pg 1-' with precisions ( n = 11) of 2.3 (for 10 pg 1-') and 1.2% RSD (for 20pg 1-I). Good agreement was obtained for the two CRMs. On-line FI-solvent extraction-FAAS for preconcen- tration of trace Mn has been reported (94/2895).The method was described for the measurement of Mn in water Chinese herbal medicine and human hair. The LOD was 0.076 pg I-' with an RSD of 1.02% and recoveries of 94-102%. Kubova et al. (94/2917) have used a cation-exchange resin (50-100 mesh) to selectively preconcentrate REEs from min- eral waters. A paper from Ukraine (94/1167) described the determination of Cd Cu Pb and Zn in cooking salt. Following extraction with l,l-dimethylethan-1-01-2% NaDDC (5 + 1) the analytes from a salt sample solution ( 4 g salt in 20ml H20) were concentrated 4-fold to give an aqueous 50% HNO solution (5 ml) which was measured by air-C2H2 FAAS. 2.1.3. Digestion Heltai and Percsich (Talanta 1994,41 1067) described the use of a moderate pressure microwave digestion system for the preparation of wheat grain lucerne leaves meat green alga spinach grape leaves tomato and green paprika.Magnesium and Zn were measured by ICP-AES Ca Co Cr Cu Fe Mg Mn Ni and Pb by FAAS and K by FAES. The microwave system consisted of closed PTFE digestion vessels which were maintained at 150-300 kPa by means of an internal cooling spiral made of either quartz or Teflon cooled by H 2 0 flowing at a minimum rate of 2 1 min-'. Dry powdered sample (0.5 g) and HN03-H202 (2+ 1) were added to the vessels. After a few minutes degassing the vessels were sealed and placed in a microwave oven. Maximum power was applied for the duration of the heating cycle which ranged from 5 to 15 min depending upon the sample and the type of microwave oven.During digestion the water and acidic vapour condensed on the cooled spiral and a continuous inner reflux was formed therefore the pressure did not increase continuously during the microwave irradiation. After a short heating up .period of about 30 s a stationary state was reached at a pressure of 150-300 kPa. The low pressure produced lower temperatures for the acid mixture thus reducing the rate of digestion. However the authors considered the lower pressure to be advantageous for the decomposition processes with the liquid phase rather than the sample being continuously renewed. The analytical results for RMs were in good agreement with the reference values. A high-pressure acid digestion system using microwave heating for the determination of Cu Fe and Zn in mussels has been reported (94/1026).The samples were measured by FAAS. High-pressure Teflon bombs were used with HNO to optimize the microwave power and digestion conditions required for complete dissolution of CRM DOLT-1. Dissolution was com- plete for freeze dried sample (0.2 g) with HNO (2 ml) after 3 min. The procedure was used for the analysis of 46 estuarine mussel samples. An open focused microwave system was described in a confer- ence presentation (94/C3492). The NIES CRM No 7 Tea Leaves was digested using HN03-HC104 giving a clear colour- less solution in 35 min. This compared well with a conventional hot-plate procedure which took 2 h. The microwave procedure was used to digest several tea samples with subsequent multi- element analysis by ICP-AES.Two digestion methods for the determination of Pb by ETA AS have been compared (94/2280). Microwave digestion and dry ashing were used with samples encountered in wine production. Samples were either heated and ashed in platinum capsules and the residue dissolved in HN03-H20 or treated in a microwave digester with HNO or H202. Both methods gave similar results and repeatability but the microwave method was preferred because of the short treatment time 30 min as opposed to 20 h for the dry ashing. 2.1.4. Direct solids and slurry sampling Solid sampling Zeeman-AAS was used to measure Cd and Pb in equine livers for human consumption (94/2582). The liver samples were fresh and not homogenized. During microsam- pling the samples were kept in closed vessels at 2-5°C and 99% relative humidity.Liquid calibration standards were used and checked using RMs. For seven of the samples the analysis of variance showed a negligible influence of sample heterogen- eity on the results. However the authors recommended that at least six microsamples from different parts of the liver should be measured to minimize this effect. Results from 49 samples measured by solid sampling agreed with those from a conven- tional decomposition method after sample homogenization. Copper was determined in solid samples of animal feed using ETAAS (94/2402). Samples ( 1-4 mg) from cylindrical frag- ments of animal feed were cut using stainless-steel scissors and placed with stainless-steel pincers into pyrolytic graphite coated graphite tubes which had the sample introduction hole mech- anically enlarged to a diameter of about 4mm.No platform or background correction was employed. Calibration was by aqueous standards. The method permitted the determination of Cu to 0.001% (10 pg g-') in feeding stuffs with a typical RSD of around 8%. Several groups in Spain have reported the use of slurry sampling for the analysis of foods. Bermejo-Barrera et al. (94/1190) used Pd-Mg(NO,) as a chemical modifier with ETAAS for the determination of Pb in mussel slurries (see also ref. 94/1026 discussed in Section 2.1.3.). Triton X-100 was' found to be the best slurry stabilizing agent. Results were comparable to those obtained by a wet digestion procedure. Bendicho (94/2886) measured Se in wheat flour slurries with an automated ultrasonic slurry sampling system for Zeeman- effect ETAAS.The NIST SRM 1567a Wheat Flour was suspended in 1 ml of an acidic diluent containing 0.005% Triton X-100. A Pd-Mg chemical modifier was used. Selenium was measured at 196.0 nm with an atomization temperature of 2900 "C. The LOD was 0.06 pg 8-l and the repeatability of the method was 8.2% (n = 10) for a 5% m/v slurry. Aluminium was determined by ETAAS in fruit juice samples (94/3282) after 20-fold dilution with 0.2% HN03 (or after filtering through paper and then diluting) and mixed on-line with Mg( N03)2 as chemical modifier. Aqueous standards were used for calibration. The RSD for 2-20 pg 1-' of A1 in aqueous standards was 7.0% (n=20) compared with 8.2% for conven- tional ETAAS. Two papers published by C6rdoba's group at the University of Murcia described the use of slurry sampling with FAAS (94/3287) and with ETAAS (J. Agric.Food Chem. 1993 41 2024). The first paper reports the use of FI-FAAS for the Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 95Rdetermination of Ca Fe Mg Mn and Zn in vegetable slurries. Cauliflower bean citrus and apple leaves were dried ground and calcined at 500°C for 1.5 h. The residue was ground and suspended in 10% glycerol solution containing 1 YO HCl sonicated for 5 min and stirred for 10 min. For Fe Mn and Zn determinations the slurry was injected into an H20 carrier stream which passed to an air-C2H2 flame. For an alternative standard additions method the carrier was 10% glycerol-1 % HC1 containing added Mn" Fe"' or Zn.For the determination of Ca and Mg the residue was suspended in 1% HCl-l% La-0.02% Triton X-100 and the slurry was injected into an on-line dilution device described in an earlier publication (J. Anal. At. Spectrom. 1992 7 1291) using the same HCl- based solution as carrier. The LODs were 12.4 5.7 and 3.3 pg g- for Fe Mn and Zn respectively with corresponding RSDs (n=10) of 1.7 0.8 and 0.9% at 57 20 and 1618 g-'. In grapefruit leaves containing 5.18% Ca and 0.4% Mg the RSDs (n= 10) were 1.21 and 1.2% respectively. The second paper reports the use of a fast-programme slurry ETAAS procedure for the analysis of Cu in biscuits bread (white and wholemeal) and breakfast cereal. The samples were first dried and then ground in a domestic mill for 5 min.No sieving was carried out. Slurries were prepared by adding 25 ml of a 20% v/v C2H50H-H20 solution containing 0.5% HNO to the ground sample (50-200 mg). The use of an C2H50H-H20 solution had been found to give the best results when compared with Triton X-100 poly(viny1 alcohol) glycerol or detergents. Suspensions were sonicated for 5 min and then magnetically stirred for 10 min. Aliquots (20 pl) were taken during the time the samples were being stirred and injected into a pyrolytic graphite coated graphite tube. Calibration was performed using aqueous standards. The NIST SRM 1568a Rice Flour and NIST SRM 1567a Wheat Flour were analysed in the same way. For comparison the samples were also analysed by an ashing procedure using HC1-HN03 (5 + 1). Optimization of the ETAAS furnace programme was such that no ashing (samples were dried at 200 "C in a single step of 20 s) or clean- out step (samples were atomized at 2500°C) were required thus simplifying and shortening the procedure.No significant build-up of carbonaceous residues inside the tube was noted. Results for the samples and SRMs showed no significant difference between the slurry method and the ashing technique. Although not possible in their work the authors in agreement with the seminal work of Miller-Ihli (J. Anal. At. Spectrom. 1989 4 295) strongly recommend the use of an autosampler with slurry sampling accessory. A candidate BCR RM was examined for Cd Fe Hg Pb and Zn by solid sampling Zeeman-effect ETAAS (94/73 1). This paper is discussed further in Section 2.11.of this review. 2.2. Speciation Studies In this year's review developments in methods for the speciation of individual elements will be discussed in the appropriate section later (2.8.1 to 2.8.9). Multi-element studies are reported here. Fan et al. (94/2624) published a paper reporting research into the methodology of speciation analysis of trace elements in traditional Chinese medicines. Liquorice root dried tanger- ine peel and a drug formulation containing 13 traditional Chinese medicinal materials were used as typical samples. Calcium Cry Cu Fey K Mg Mn Ni and Zn were determined by ETAAS. Cobalt Cu Mn and Ni were also measured by HPLC and F- C1- NO3- SO4'- and PO4- were determined by anion-exchange chromatography. Fluorimetry was used to determine Se and catalytic polarography for Mo.The paper reports the use of eight parameters and eight species distri- butions to describe 'primary' and 'secondary' level speciation analysis for the samples. 2.3. Developments in Methodology for Flame Atomic Absorption Spectrometry Minimal sample preparation and the use of resins and FI with FAAS has already been mentioned in Sections 2.1.1 and 2.1.2. where some methods for direct measurement and preconcen- tration were discussed. Most of the improvements for FAAS concern obtaining better LODs for this widely available and relatively inexpensive technique. Li et al. (94/730) have used a liquid emulsion membrane for preconcentration of trace elements. The membrane was developed for the determination of Cd Co Cu Fey Mn Ni Pb and Zn in water beer and soft drinks.It consisted of a water-in-oil emulsion of Span 80,2-ethylhexyl phosphoric acid mono-2-ethyl hexylester di-2-ethylhexyl phos- phoric acid kerosene and an aqueous solution of 1 mol 1-' HCl and 0.02 mol 1-' H2S04. Sub-samples were degassed by stirring and heated with HNO and HC104 for 1 h at 50°C. The pH of the resulting solution was adjusted to between 4.5 and 5.6. The emulsion was added to the stirred solution in an extraction funnel and the stirring continued for a further 10 min and the phases were allowed to separate. The sample solution was removed and the emulsion cleared by the addition of n-butanol. After a few minutes the stripping solution was taken and analysed by both FAAS and ETAAS. Differences in the results from the two techniques expressed as percentages of the ETAAS values were in the range of +lo% (water) *9% (beer) and 14% (soft drinks).The agreement was considered to be satisfactory for the low concentrations of the analytes. Slotted tube atom-trapping with a quartz tube was used to determine Mn in drinking water human hair and beverages (94/851). Diagrams showing the structures of the tube and trap are given in the paper. Air and C2H2 flow rates were 3.0 and 1.5 1 min-' respectively. Manganese recoveries were 97.2-102% although Cay Cr and Mg were reported to interfere in its determination. The method was reported to be 3.4-fold more sensitive than conventional FAAS. Memon et al. (94/2250) have published work describing a new approach to FI with mixed solvents for the determination of Cu by FAAS.An FI manifold with phase separator was connected to the AA spectrometer. Toluene-xylene ( 1 + 4) was studied for the extraction on-line of the chelated product Cu-5,7-dibromo-8-hydroxyquinoline. The study was based on the idea that a mixed solvent will have lower density surface tension and viscosity and would therefore help to increase the efficiency of nebulization and atomization processes. Five samples were studied the NIST SRMs 1567 Wheat Flour 1573 Tomato Leaves 1575 Pine Needles and 1577 Bovine Liver as well as tap water. Samples were prepared by acid digestion and diluted to a concentration that fell within the range of the calibration curve whilst maintaining the pH. Under optimum conditions the calibration curve was linear up to 0.4pg Cuml-' and the LOD was 7ngml-' with extraction.The RSD (n= 8 ) when 1 pg ml-l of Cu standard was injected was 0.5%. An enrichment factor of 16 and rapid sample throughput 180 injections h-' was obtained. Good agreement was obtained between the FI extracted samples and certified values. An LOD of 7 ppb was reported for Cu in pickled gingers determined by FAAS after acid digestion with HN03-HC104 and extraction with IMBK (94/2179). Lead was also measured and an LOD of 30 ppb reported. Yebra et al. (94/703) measured Cu to indirectly determine reducing sugars in wine using a continuous precipitation system based on the reaction with Fehling's solutions. No sample pre- treatment was required. Copper oxide was precipitated on-line by injecting the Fehling's solutions into the wine carrier which was directly aspirated into an air-C2H2 flame.The wavelength was 324.7 nm. The reducing sugars could be determined in the 96 R Journal of Analytical Atomic Spectrometry April 1995 Vol. 10range 10-110 pg ml-' with an RSD (n= 11) of 2.7% for 50 pg of glucose ml-'. 2.4. Developments in Methodology for Electrothermal Atomic Absorption Spectrometry Details of a fast furnace programme for Pb in drinking water based on the US Environmental Protection Agency method 200.9 is given in a paper by Schneider and McCaffrey (94/639). The paper also describes an FAAS method for Cu in potable water. The possibility of standardless analysis was reported by Ma et al. (94/3 104) using Pd and tartaric acid as chemical modifiers and a tungsten foil platform (WFP) for the determination of Cd in CRMs (including Pork Liver Wheat Powder Tea Leaf and Cabbage) and seawater.The authors had published an earlier paper which described the use of a tantalum foil platform for Cd measurements but they found that WFPs have a longer lifetime. In addition the common oxides and carbides of W sublime at moderate temperatures making the W surface 'self-cleaning' during high temperature treatments. The use of a Pd-tartaric acid mixed modifier eliminated matrix effects and removed the two peaks observed during the atomiz- ation of some complex environmental samples. Quantitative analytical data were obtained using standardless analysis with an LOD of 0.3 pg and an RSD <5%. The determination of As and Pb in wine by ETAAS was described by Bruno et al.(94/2935). Arsenic was measured with Pd as a chemical modifier after dilution of the wine with HNO (8 + l) heating to 150 "C for 90 min and then diluting to 10 ml with de-ionized H,O. The LOD for As was 6.6 ng ml-'. For Pb the wine sample was diluted with HNO (1 +4). A Pd-Mg chemical modifier was used and the LOD for Pb was 15.5 ng ml-'. The LODs for As and Pb were 20-30 times below the maximum limits proposed for wine by Brazilian control agencies and therefore the methods were suitable for monitoring the levels of these analytes in wine. In a conference presentation (94/C3379) Lin et a!. described a new method for the determination of Ge by ETAAS. Germanium was of interest because it is thought to be involved in cancer prevention and many Chinese herbs and plants contain trace Ge. The method uses the fact that in dilute HN03 Ge will react with ammonium molybdate to form a stable germanomolybdate.This compound was extracted into butyl alcohol and determined directly in the organic phase. By using an ammonium molybdate-impregnated graphite tube the sensitivity of the determination was enhanced. The LOD was 6.0 x g and the RSD was 5%. 2.5. Developments in Methodology for Plasma Atomic Emission Spectrometry Two papers by Krushevska and Barnes (94/3135 94/3262) described the determination of Si in foods using ICP-AES. Silicon as well as Al Ba Sr and Ti were determined in standard food and milk powder samples after LiB02 fusion (94/3135). The resulting ash was mixed with H20-HN0,-H,O,-Sc solution and heated for 10-15 min on a hot-plate.Digests were measured by ICP-AES after dilution with H20. Data for total mixed food diet samples obtained by the fusion method agreed well with data for spiked recovery determinations and from three other independent sample preparation methods. Low concentrations of Si were determined in freeze dried homogenized commercial foods (e.g. canned meat fruit milk) following a new microwave dissolution procedure (94/3262) incorporating the addition of water soluble tertiary amines. Carrion et al. (94/2909) aimed to develop a direct rapid and simple method for the determination of Ca Cu Fe Mg P and Z n in human milk by ICP-AES by direct aspiration of emulsified samples. Milk samples were emulsified with ethoxy Journal nonylphenol to 0.03% m/v.The emulsions were then diluted 10-fold with HN03 to 1% v/v. Calibration standards were made with the same amount of emulsifier. The accuracy was assessed by analysing NIST SRM 1549 Non-Fat Milk Powder. There was no significant difference between certified and obtained values at the 95% confidence limit and the RSD for real samples (with no internal standard) was in the range The efects of low acetic acid concentrations on multi-element analysis by ICP-AES were investigated during development of a method for determining metal impurities in vinegar (94/2398). The magnitude and .mechanism of any interference were revealed from measured changes in the solution uptake rate the departure of the ratio of the line intensity in acetic acid solution and in H 2 0 from unity and the changes in ion-to- atom line intensity ratio. The LODs and RSDs for Al Cd Cr Cu Fe Ni Pb and Zn were almost equal for aqueous solutions and solutions of 3 and 10% acetic acid.Sanz-Medel and his group have further investigated the nature of volatile Cd species (94/2915). In this paper the formation of volatile Cd species with sodium tetraethylborate (NaBEt,) and its use to increase the sensitivity of Cd determi- nations by ICP-AES was applied to the analysis of tea infusions and seawater samples. 0.3-2 % . 2.6. Developments in Methodology for Inductively Coupled Plasma Mass Spectrometry A short review of the use of ICP-MS in a food science laboratory over the past decade has been published (94/1264). Applications including total analyte determinations isotope ratio measurements speciation studies and on-line coupling with HPLC were discussed.The use of ICP-MS for the analysis of natural and mineral waters has been studied and reviewed by Rosin et aE. (94/3213) who concluded that the ability to measure 60 elements with excellent sensitivity made this technique particularly suitable to water analysis. Goosens et al. (94/2584) have described the accurate determi- nation of Pb in wines by ICP-MS. The effect of preliminary sample preparation using an aqueous ethanolic medium on signal suppression or enhancement was investigated in conjunc- tion with the ability of an internal standard to correct for it. The method entails diluting wine with HN03 (lO+90) in the presence of T1 as internal standard with measurement against external calibration.The LOD was 0.2 pg 1-'. The Pb contents of the wines ranged from 1.63 to 58.8pg 1-l with standard deviations ( n = 3) ranging from 0.05 to 0.9 pg 1- '. The effect of using an Ar-N plasma to reduce polyatomic interferences during multi-element analyses by ICP-MS has been studied using CRMs (94/3112). Data for 38 elements were reported for MAM2/TM Mussel Tissue TORT-1 Lobster Hepatopancreas NIST SRM 1566a Oyster Tissue NIST SRM 1547 Peach Leaves and NIST SRM 8431a Mixed Diet. The samples were subjected to overnight digestion with HN03 in stainless-steel pressure bombs with PTFE liners. Following dilution and addition of In and Bi as internal standards the digests were measured with external calibration standards using an Ar-only plasma with low (0.755 1 min-') or high (0.955 1 min-') aerosol carrier flow rates or an Ar-N plasma (aerosol N 8% flow rate 0.755 1 min-I).Under normal default operating conditions (Ar-only and low aerosol flow) when the instrument had been optimized for signal response the addition of 8% N improved the measurement of 51V 53Cr 67Zn 75As and 77Se in the five RMs. The determination of 68Zn was improved by the addition of N for all the RMs except Peach Leaves. Of the other 28 elements which were determined those which had certified or reference values were with few excep- tions in good agreement with these values when measured of Analytical Atomic Spectrometry April 1995 Vol. 10 97Runder all three plasma conditions. The exceptions were the values for some REEs when a high aerosol carrier gas flow rate was used.The increase in LODs when N2 was added was not so great as to cause any problems with the multi-element determinations. Ground and drinking water samples were analysed with the aim of deciding if ICP-MS was suitable for the determination of low levels of A1 in these matrices (94/2637). Indium was used as an internal standard the calibration curve was linear up to at least 100 pg 1-' A1 and the LOD was 0.4 pg 1-'. The results from ICP-MS compared well with those from ICP-AES for samples with A1 concen- trations above the LOD for ICP-AES 20 pg 1- '. Aluminium has also been determined in test diets and animal tissues by ICP-MS following microwave digestion with HNO (Food. Chem. Toxicol.1994 32 697). Replicates of the RMs IAEA H-5 Animal Bone and NIST SRM 8431a Mixed Diet were analysed and monitored as inter-batch standards. Since the Mixed Diet SRM had only a recommended value (4.39 1.07 pg g-I) for Al measured values were expected to be within 20% of the quoted recommended concentration. The measured mean was 3.67k0.67 pg 8-l (n=24). No A1 value was given for Animal Bone and this RM was used to assess repeatability and to act as a matrix matched carrier for an A1 spike for bone samples since experimental sample availability was limited. The mean A1 concentration for Animal Bone was 1.45 range 1.25-1.65 pg g-' A1 (n=21). The same paper also describes the use of SEC-ICP-MS to characterize the A1 in gut contents following ingestion by guinea pigs of test foods.Although one of the test diets contained citrate as orange juice the chromatographic studies indicated that the A1 was not present as citrate in the soluble fraction of upper intestinal contents. Other publications have reported the use of HPLC-ICP-MS for speciation studies and these are reported in the sections dealing with specific elements. For example As speciation using this methodology has been described by several authors (94/2197 94/2214 and 94/2974) and these papers are discussed in Section 2.8.2. of this review. 2.7. Applications of X-ray Fluorescence Spectrometry The Ca and K content of Turkish fresh green tea black tea and tea residue have been determined (94/2162). The data from XRF and the suitability of this technique for this type of analysis were discussed and the data compared with those from AES.The factors affecting the accumulation of Ca and K in tea were also highlighted. An Australian paper described a method for total glucosinol- ates in oilseed rape and other Brassica oilseeds in which glucosinolates are determined indirectly by the measurement of oxidized S (S6') by XRF (94/2451). Results were highly correlated with glucosinolate content as determined by glucose release a standard method used widely in Australia. The correlation of glucosinolates with S6+ was closer than the correlation with total S. The latter correlation forms the basis of the existing XRF method used within the EC in recent years. The advantages of using S6+ derive from the linearity of the regression and the elimination of errors caused by variability in protein content. The method allows the rapid screening of breeding lines to ensure low glucosinolate content.2.8. Progress for Individual Elements 2.8.1. Antimony Antimony is included here because of the recent theory that there is a possible association of Sb with infant cot deaths and the subsequent increased interest in its determination. Smichowski et al. (94/3340) described a method for precon- centration of Sb in tap and seawater using activated alumina. Tap water ( 5 ml) or seawater ( 10-75 ml) were passed through a PTFE column packed with the H f form of activated alumina which had been washed with HC1 and H20. The retained Sb was eluted with 0.5-2.0 ml of 4 ml HC1 and a 20 pl portion analysed by ETAAS with deuterium background correction.The LOD was 0.2 pg with RSDs of 8 and 1% for 10 and 90 ng ml-' Sb respectively. The only significant interference reported was from Sn. Antimony and Bi were determined in canned foods using HG-AAS (94/3158). Samples (10-15 g) were treated with HN03-H2S04 and the resultant clear digest was mixed with KI containing 10% ascorbic acid and diluted to a final volume of 25 ml with H20. The wavelengths were 223.1 and 306.8 nm for Bi and 217.6 nm for Sb. The hydrides were generated using 6 mol I-' H2S04 and 0.8-1% NaBH,. The LODs were 0.88 and 2.1 ng ml-' for Bi and Sb respectively with corresponding RSDs of 4.3 and 7.5%. 2.8.2. Arsenic Three papers from the groups at the University of Valencia and the Institute of Agrochemistry and Food Technology in Valencia deal with different aspects of As determinations.A study has been made of the interferences effecting As determi- nations in mussel products by ICP-AES (94/2583). Dry ashing followed by HG-AAS was used to measure As in orange juice products (94/3170). The LOD for the ICP-AES study was 0.1 pg g-' whilst that for HG-AAS was 0.1 ng g-'. Seafood often contains more As than other food products. Inorganic forms of As are generally more toxic than organic forms however most of the As in seafood is present as non- toxic arsenobetaine. With the likelihood of legislation in the future that will require the ability to separate inorganic from organic forms of As methods continue to be investigated and developed. The third paper from Valencia (94/2980) reported a procedure for the determination of inorganic As in seafood products.The authors modified an existing method by Lunde which released and separated inorganic As in one stage and was based on conventional distillation of inorganic As as AsC1 in the presence of HCl. This process was time consuming and the use of a microwave oven to provide the appropriate temperature for distillation was studied. The different param- eters that control the distillation were investigated and the optimized method applied to seafoods. The organoarsenic compounds were not decomposed by the microwave procedure. Inorganic As was determined by HG-AAS and total As by ICP-AES. The method for inorganic As has an LOD of 0.068 pg g-' (dry mass) or 0.023 pg g-' (wet mass) of mussel product.Pallanca et al. (94/C3440) in a conference presen- tation described a different approach to speciate toxic As in foodstuffs. Enzyme extraction techniques were used to solubil- ize As species without altering the speciation. The extracts were then subsequently analysed by HPLC-ICP-MS and HG-AAS. The former allows full quantitative speciation analy- sis whereas the latter provides a rapid screening method for total toxic As Larsen et al. (94/2197) and Branch et al. (94/2214) also determined As species by HPLC-ICP-MS. Larsen et al. isolated As species found in extracts of 11 samples of shrimp crab fish fish liver shellfish and lobster digestive gland (hepato- pancreas). Tissues of shrimp crab dogfish lobster mussel plaice and tuna were freeze dried and finely ground.a portion was suspended in CH30H-CHC13 (5+2) by sonication for 30 min then centrifuged and the supernatant extracted with H20. The aqueous extract was purified on a C18 cartridge and separated by ion-exchange chromatography. For anion exchange the mobile phase was 0.1 mol I-' NH,HCO adjusted to pH 10.3 with aqueous NH,. For cation exchange the mobile phase was 20 mmol 1-' pyridinium adjusted to pH 2.65 with formic acid. The chromatography was coupled to ICP-MS 98 R Journal of Analytical Atomic Spectrometry April 1995 Val. 10and m/z = 75 monitored. Trimethylselonium iodide and hexa- hydroxyantimonate(v) were used as internal standards at m/z 82 and 121 respectively. The LODs were in the range 10-59 ng g-' (dry mass) with the exception of arsenobetaine for which the LOD was 360 ng g-'.The amounts of each species (as the As atom) relative to the total As extracted from the samples were arsenobetaine 19-98 YO arsenocholine and trimethyl- arsine oxide O-O.6% and tetramethylarsoniumion 0-2.2%. Additionally an unknown species was present in the shellfish and the lobster digestive gland (3.1-18%) and a second unknown species was present (0.2-6.4%) in all samples. The contents of arsenite and arsenate were 0-1.4% and of dimethyl- arsenate 8.2-29%. Monomethylarsonate was only found in oyster at 0.3% of the total As. The intake of inorganic As via ingestion of the seafood samples analysed did not represent a toxicological problem to humans. In the paper by Branch et al. (94/2214) non-toxic arsenobetaine was identified using ion-exchange chromatogra- phy as the major As species in cod dab haddock mackerel plaice and whiting.Mackerel also contained dimethylarsinic acid and possibly a lipid-bound species. No monomethylar- sonic acid was found in any of the fish. Levels of toxic inorganic species were low in all cases. When fish were subjected to an enzymatic digestion procedure based on trypsin no degra- dation of arsenobetaine to more toxic species was observed except for one of the plaice samples in which dimethylarsinic acid was observed. The levels of the growth promotor 4-hydroxy-3-nitrophenyl arsonic acid (Roxarsone) in samples of tissue from chickens fed on a diet supplemented with this compound were deter- mined by ion-exchange and reversed-phase LC coupled to ICP-MS (94/2974).Samples were extracted with trypsin at pH 8.0 and after centrifugation and pH adjustment the super- natant was analysed by anion-exchange chromatography with further separation of Roxarsone from other species achieved by reversed-phase LC. No Roxarsone was detected in chickens fed on growth promotor with or without a withdrawal period. The limit of quantification was 25 ng g- '. Other papers published during this review period report the determination of total As by ETAAS in fish (94/1778) edible vegetable oils (94/1070) and in vegetables and food samples (94/2804 94/C3409). Hydride generation with ICP-AES was used to analyse 41 common Malaysian vegetables (94/2099). 2.8.3. Barium Barium distribution in some Italian potable waters was studied using Zeeman-effect ETAAS (94/893).Results for the Regglio Emilia Plains area indicated that Ba concentrations ranged from 10 to 925 pg l-' with appreciable differences among the hydrogeological systems studied. Preliminary speciation stud- ies suggest that Ba is present in water as inorganic Ba or as complexes with low molecular weight organic compounds. Intracavity laser spectral analysis of trace amounts of Ba in water by sample evaporation in a standard graphite electrother-. ma1 atomizer was described by Burakov et al. (94/2929). The LOD obtained by this method for Ba was 0.2ng 1-'. This compares very well with LODs for modern spectrometers of 0.002-0.04 pg I-' (as quoted by Burakov et al.) and was 2 or 3 orders of magnitude lower than those obtained by a pulsed dye laser.The precision of the.method was 10% for the lowest concentrations measured The authors also determined I which is discussed in Section 2.8.7. 2.8.4. Chromium Posta et al. (94/3280) used high performance flow FAAS for automated on-line separation and determination of Cr"' and CrV' and for preconcentration of CrV' in drinking waters. The eluent stream CH30H-H,PO (1 + 4) from the c18 Cr speci- ation column was introduced into a slightly reducing air-C,H2 flame via a high pressure nebulizer system. With 100 pl sample injections the LODs were 0.03 and 0.02 pg ml-' for Cr"' and Crvl respectively. In a conference presentation (94/C1937) Yehl et al. evaluated FI-FAAS for Cr speciation. By judicious adjustment of the parameters controlling the retention and elution of Cr"' and Crvl the authors were able to improve the procedure developed by Sperling et al.(Anal. Chem. 1992 64 3101). The modified method had a significantly greater capacity and efficiency for Cr"' then for CrV'. 2.8.5. Iron Methods for the determination of haem and non-haem Fe have been reported in three papers from Japan. Oshima et al. (94/876) describe a simple and rapid procedure which involves extracting both forms of Fe from foods with IMBK under acidic conditions. By washing the IMBK layer with H20 the non-haem Fe was transferred to the aqueous layer. Iron in both phases was detected by Zeeman-effect ETAAS. The method was applied to confectioneries fortified with Fe at 40-50 pg g-' and gave recoveries of > 84%. The same method was used by Oshima (94/1709) to isolate haem and inorganic Fe from Fe-containing protein in liver.One difference was that the non-haem Fe was removed from the IMBK by washing with 1% HCl Kojima and Yasui (94/898) extracted haem Fe with 80% acetone acidified with HC1 and non-haem Fe was extracted using 1% HCl at 80°C. After adjusting the acetone concentration of extracts to 40% solutions were passed through a cartridge. Haem Fe was adsorbed whilst non- haem Fe passed through. The haem Fe was eluted with acidified 80% acetone. The eluates were evaporated to dryness then wet digested with HN0,-HClO and the residue taken up in HCl and measured by AAS. The ratios of haem Fe to total Fe in processed foods were almost the same as in the meat starting material. 2.8.6. Mercury Trace Hg in well water grain and plant samples was determined using a gold-coated graphite tube a sample insertion system and a flowing hydride generator (94/720).Samples (e.g. grain 0.5 g) were mixed with V205-H3P0 and left overnight. The mixture was digested at 140 "C and then the cooled digest was mixed with 2 ml H2S04 and further digested for 15 min. The digest was mixed with 1 ml of 5% KMnO left for 3-4 h before being treated with hydroxylamine and then diluted to 50 ml with H20 ready for measurement. The LOD was 0.8 ng 1-l and the RSD (n= 11) was 0.6-2.4%. The eflect of I - addition on Hg determination by AFS using a Cr" reduction system was reported by Tanaka et al. (94/3041). The authors had already established that the use of Cr" instead of SnC1 for the CV generation of Hg in the presence of I- could completely reduce the Hg-I- complex to elemental Hg enabling Hg detection at the pg 1-' level by an FI-AFS technique.Addition of I- ions (> 10 mg 1-') to Hg solutions led to stabilization giving improved repeatability and LOD. The system was further evaluated using real water samples. Cold vapour-AAS was used to determine the Hg content of fish and fish products (94/1020). Samples (0.2-0.3 g) were digested with HNO,-H,SO,-HCl (4+2 + 1) and then the Hg oxidized to Hg2+ with KMnO,. Excess KMnO was removed by addition of 20% hydroxylamine hydrochloride. The sample plus saturated NaCl were analysed by CVAAS the Hg vapour being generated by SnC1,-H,S04. The results for various fish products were listed. Zhu et al. (94/2730) also used CVAAS to determine Hg in pork liver using a NABH,-HCl mixture to generate the vapour. Abdallah et al.(94/1088) studied the influence of bromide bromate iodide iodate periodate sulfide sulfite and thiosulf- ate on the determination of Hg in acidic and alkali media in Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 99Rrelation to the analysis of foods and water. The effect of a variety of insecticides was also investigated. Ofunack and Cyanox decreased the Hg absorbance signal by about 65%. In a different publication Buzasi-Gyfori et al. (94/1104) reported the metal content of pesticide formulations and vegetables using arc source AES and AAS. They found that the concentrations of metals in vegetables treated with metal- containing pesticides increased considerably. 2.8.7.Iodine Total I concentrations in 2 milk powders and human serum were determined using ICP-MS by Vanhoe et al. (94/2554). It was shown that the oxidation state of the analytes had a strong impact on analytical performance. If the I was present as iodide and HNO was used for acidification the observed signal was not stable and samples spiked with iodide yielded erroneous recoveries of up to 750%. Since the I in milk is almost exclusively present as iodide HNO was not suitable for matrix digestion. It was found that when NH solution was used as diluent the excessive I recoveries did not occur. Good agreement with certified values was obtained for BCR 150 and 151 Spiked Skimmed Milk Powders and NIST SRM 1549 Non-Fat Milk Powder. For human serum results from samples treated with HNO or with NH solution were not significantly different from one another.Results were reported for a second generation biological RM Freeze-Dried Human Serum (University of Ghent Belgium) and for sera from healthy individuals. Bermejo-Barrera et al. (94/2958) determined iodide indirectly by ETAAS measurement of the Hg signal generated when small amounts of iodide and Hg were heated together in a graphite furnace. The method was applied to a range of tap waters. The LOD and limit of quantification were 3.0 and 10.1 pg iodide I-' respectively with RSDs (n=7) ranging from 5.1 to 8.9% depending upon concentration. Direct measurements of trace amounts of I in water and urine were made using intracavity laser spectroscopy (ICLS) by Burakov et al.(94/2929). Minimal sample preparation was required for the laser probing of the vapours over the surface of the heated liquid in a closed cell. The LOD was 0.015 mg 1-'. 2.8.8. Selenium Veber et al. (94/2925) determined both As and Se in highly mineralized mineral waters by HG-AAS. The atomization was performed either conventionally in a heated silica tube or in the graphite furnace after collection and thermal decomposition of the hydrides. In most cases the determination of As was not subject to problems. Significant matrix effects were found only with waters containing the higher Mg Na and SO4- concen- trations. The conventional flow-through HG technique was good for analyte concentrations in the range 1-50 pg 1-'. For determinations of As and Se at lower concentrations in situ preconcentration in the graphite furnace was applied giving satisfactory precisions of 2-l6% RSD in the concentration range 0.5-10 pg I-'.Selenium was also determined (94/3151) in water following treatment with HC1-H,SO,-H2O2 and subsequent reaction with NaBH and measurement by AAS at 196nm. Hydride generation-AAS was used to measure Se in fresh fish samples from South-Eastern Spain (J. Agric. Food Chem. 1994 42 334). The study was carried out because high consumption of fish represents one of the main dietary sources of Se in this area and data for dietary Se intake was lacking. The muscular meat from 31 of the most common species of fish were lyophilized pulverized and after homogenization stored at - 18 "C prior to analysis.Sub-samples (300 mg) were treated with HNO diluted with H20 and further heated with HCl and diluted. Hydride generation was achieved using NaBH4-NaOH. The samples were analysed by the standard additions method and BCR CRM 278 Mussel Tissue was also included in the analyses. The LOD was 2.83ng and all the samples exceeded this value in the range 0.150-2.014 pg g-'. The repeatability was 4.00-4.71 YO RSD. The daily dietary intake of Se from fish was calculated as 15.78g d-' for an adult in Andalusia Southern Spain. Another Spanish group (94/2981) measured the Se content of fruit juices by FI-ETAAS. Selenium was successfully deter- mined in fruit and tomato juice by using the standard additions method (juice samples were diluted 10-fold) with an RSD of 4.5-12.0%.The LOD was 5 pg 1-'. Fifty typical Italianfoods were analysed for Se using Zeeman- eflect ETAAS after decomposition with HNO in a sealed high pressure asher (94/1678). The advantages of the method included no contamination or loss of analyte short treatment time and improved safety for operators. A copper chemical modifier was used with a L'vov platform. The authors considered the method to be simple and relatively fast being suitable for samples containing 0.05 pg g-' Se or more. Spectrofluorimetry and HG-AAS were compared for the determination of Se in Australian foodstuffs (94/863). The efficiencies of acid mixtures used for digestion were also compared. An HN03-HC104 mixture was the best for spectrofluorimetry and this mixture or an HN03-HC104-H2S04 mixture were suitable for HG-AAS.No matrix interferences were encountered. Spectrofluorimetry was more sensitive than HG-AAS with LODs of 0.001 and 0.033 pg g-' respectively. High levels of Se were found in cereals meat fish and wheat products with relatively low levels in milk products. Fruit and vegetables contained very little Se and negligible amounts were found in beverages. A Chinese paper compared three methods for determining Se in food samples (94/947). The methods were 2,3- diaminonaphthalene molecular fluorimetry HG-AFS and HG-AAS. Whilst the precisions and accuracies were reported to be similar for all three techniques the absolute LODs for HG-AFS and HG-AAS were 1.2 and 0.9 ng respectively lower than the value of 3.9 ng for molecular fluorimetry. There was no significant difference between the results from the three techniques for six RMs.Molybdenum and Se were determined in rice and sesame by Zeeman-effect ETAAS (94/726) after sample digestion in Jacobs et al. (94/2163) investigated the Se distribution in egg white proteins. The proteins were separated by ion exchange and fast protein LC and the distribution of Se detected by FI-AAS. Nine protein fractions were identified by sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS- PAGE). Over half (56%) of the total Se was found to be associated with ovalbumin which contained approximately 500 ng g-'. Flavoprotein was the richest Se-containing protein (1800 ng g-') with the concentrations in other proteins ranging from 359 to 1094ng g-'. In a paper presented at Pittcon '94 in Chicago preliminary results from coupling headspace GC with AES to determine trace levels of flavours off-flavours and contaminants in variety of food products (94/C1930) were reported.Ten organoselen- ium compounds were found in fresh garlic dry garlic powder and related plants (Chinese chives and radish). The system provided high sensitivity without tailing for both S and Se compounds. It will be very interesting to read the full pub- lished paper. HN03-H202. 2.8.9. Tin Several Chinese papers have reported the determination of total Sn in foodstufls. Wu (94/931) used FAAS to measure Sn in Baijiu (an alcoholic drink). Samples (25 ml) were mixed with NH4C1-NH,SCN-C2H50H (2 + 2 + 1 ) and the solution ana- lysed directly with an ethylene flame. The presence of NH4+ increased sensitivity.Tin in canned foods was detected using 100 R Journal of Analytical Atomic Spectrometry April 199.5 Vol. 10HG-ICP-AES at 283.99 nm (94/1229). The samples including beans peas mushrooms tomato sauce and cola beverage were digested with HNO3-HC1-H,SO and a portion of the digest neutralized with NaOH or KOH before dilution with HCl. The hydride was generated with KBH,-KOH with Ar as carrier gas. Tin(1v) was determined in mineral and drinking waters using a chemically modified probe AAS (94/2281). The optimum conditions for the use of a trioctylphosphine oxide (TOP0)-coated tungsten probe were investigated. The probe was immersed in an acidified sample for 5 min rinsed with HCl for 5 s and transferred into the graphite tube of an AAS system.The sheath gas was Ar with ashing at 1000°C for 15 s and atomization at 2700 "C for 7 s. The LOD was 0.4 ng ml-' with a 5.7% RSD (n= 11) for water samples containing 4 ng ml-'. In situ preconcentration for the determination of ultra-trace amounts of Sn in tap water and serum samples was described in a conference presentation (94/C3377). Tin was retained as its chlorostannate complex on a column packed with a strongly basic anion exchanger and then eluted into the HG system with HN03. The hydride and H2 gases evolved were separated from the liquid phase in a gas-liquid separator and transferred to a palladium-coated graphite tube. The sampling frequency was 25 h-l with an LOD of 0.05 pg 1-l using 10.7 ml sample. A second conference presentation (94/C3387) described the simultaneous determination of Pb and Sn in food by HG-FAAS. Analytical data for bean powder orange juice canned rice and milk samples were presented.In three papers by Forsyth et al. the speciation of organotin compounds was reported in edible oils (94/756) in fruit juices (94/785) and in PVC [poly(vinyl chloride)] products used for containing and transporting food for retail and bulk shipment purposes (Food Addit. Contam. 1993 10 531). In all cases the organotin species were detected using GC-AAS with confirmation by GC-MS where appropriate. For edible oils the butyl- cyclohexyl- octyl- and phenyltin compounds were extracted using 0.05% tropolone in 0.04 mol 1-' HC1-CH30H. Methyl derivatives for GC were formed by Grignard reaction.Fruit juices were similarly extracted using 0.05 YO tropolone in 25 YO pentane-diethyl ether. For the extraction of PVC products three solvents tetrahydrofuran xylene and methylene chloride were evaluated. The latter extracted more than 97% of the total extractable organotin in two extractions and resulted in the highest recoveries of analytes from all three PVC products. 2.9. Single and Multi-element Analysis of Foods Water samples were collected from 55 locations from tube wells and groundwater sources used for drinking water in the Hooghly District of West Bengal India (94/1796). Arsenic Ca Cd Cr Cu Fe Hg K Mg Mn Na Pb and Zn were mea- sured by AAS. Iron and Mn were present at levels above the World Health Organisation (WHO) Maximum Admissible Concentrations in 76 and 70% of all cases respectively.Zinc was present in 65% of the samples with a maximum value 33 times greater than the WHO guideline value. Cadmium and Cu were also present at elevated concentrations in some samples providing evidence for groundwater pollution in this area. Multi-element analyses of beverages have been reported. Aluminium P and Si were determined in fruit juices stored in glass and aluminized containers (94/1719). Juice stored in aluminized containers with an internal plastic coating did not show increased A1 concentrations. Lead released from crystal decanters for cognac (94/1814) and sherry (Food Chem. Toxic. 1994 32 285) storage was measured in the beverages by ETAAS. After 15 months storage there was nearly 800 ppb Pb in cognac from unprotected decanters but no Pb migration when the interior was protected by a glass sheet or had been treated by ion exchange with kaolin.The results from studies with sherry indicated that sufficient ageing of the lead crystal prior to use reduces the health risk to adults caused by Pb migration into beverages. Matsushige and Oliveira (94/1055) determined Co Cr Cu Fe Pb and Zn in Brazilian beers by ICP-AES. Bottled and canned beers were treated with HN0,-H202 or HN03-03. The results showed good quality of the beers with respect to their metal content. Infant milk samples were measured using FAAS for Cu Fe Mn and Zn (94/1027). The samples were dry ashed and the residue taken up in HN03. Anderson (94/1867) reported the results from a longitudinal study of trace element changes in human milk during the first 5 months of lactation.Samples were analysed by ICP-AES. The elements found in all samples in measurable quantities were in order of highest to lowest concentrations Zn Si Cu Fe Ba and Sr. Copper Fe and Zn concentrations reduced with time. Other elements detected in some but not all samples were Al Li Mn and Ti. In Spain milk samples have been analysed for Ca and Mg by FI-AAS (94/1126) and the seasonal changes for Cu Fe Mn and Zn in natural cow ewe and goat milk samples have been studied using FAAS (94/1799). Indian cow and buffalo milk from animals near a coal-fired power plant and from unexposed areas have been analysed for Cd Co Cu Mn Ni Pb and Zn (94/1795). The samples collected from around the power plant were considered to be contaminated with these metals. Arsenic Cd Cr Pb and Sn were determined in oils and fats using ETAAS (94/2119) The LODs for oil were As 2 Cd 0.25 Cr 1 Pb 5 and Sn 10 ppb.The RSDs were 4% for 50 ppb As 3% for 10 ppb Cd 8% for 50 ppb Cr 2% for 10 ppb Pb and 6% for 15 ppb Sn. Generally analyte levels were low in refined oils but could be abnormally high for some crude oils. In a conference presentation (94/C3406) the Pb contents of 14 fried oil samples ranged from 99.7 to 164.8 pg kg-l. The Pb was measured by ETAAS after treatment of the oil samples with KOH-C2H,0H with PdC12 as chemical modifier. The effect of highway traffic on the Cd and Pb content of fruits and vegetables grown along roadsides in Libya was investigated using ETAAS (94/1815).Crops from farms along the Tripoli-Zawiya major road were compared with those from farms in Waddy Al-Rabia away from any large road. The samples were digested using dry ashing. Lead in crops grown near the major highway was significantly elevated whilst Cd was elevated in all crops except potatoes. Substantial amounts of the analytes could be removed by washing the samples with triple distilled water. Cadmium and Pb were also determined in all-wheat pastas and pasta products by ETAAS (94/1660) and in foods of animal and vegetable origin using Zeeman-effect 'ETAAS (94/1676). Lead only was analysed by ETAAS in Jordanian wheat flour and bread samples (94/828) and Cd only in feed and food crops (94/1082) and in pulses (94/1659). Chromium Cu and Zn concentrations in Spanish vegetables grown in Tarrogona Province were determined after digestion in PTFE bombs with HN03 (94/1204).The resulting digest was diluted and then Cr measured by Zeeman-effect ETAAS Zn by FAAS and Cu by ICP-AES. The Cu and Zn values agreed well with published values whilst the Cr values were higher than some previously reported values. 2.10. Characterization Studies Multi-element analysis of green cotee has been investigated as a means of determining the origin of this commodity (94/1855). The concentrations of the following elements were measured in green coffees of the Arabic species produced in crop year 1987/88 in South American countries and in Papua New Guinea Ba Br C Ca Co Cr. Cu Cs Fe H K La Mg Mn N Na Rb Sc Sr and Zn. Analyses were carried out using ETAAS FAAS NAA and combustion elemental analysis.Of Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 101 Rthe elements studies Mn seemed to be the best indicator of origin with C Co Cs Na and Rb also of interest. being by far the most important followed by 1-hexanol K N compounds and total phenols. Moret et al. (J. Agric. Food Chem 1994,42,1143) determined K Li and Na (by FAES) and Ca and Mg (by AAS) as part of a set of 27 chemical variables (18 inorganic and classical determinations and 9 aroma compounds) for a chemometric multi-year study of the characterization and classijkation of five Venetian white wines. Best results for the 59 samples of different vintage were obtained by canonical variate analysis (overall correct classification about 90%) which showed that several variables contributed to the classification cis-3-hexen- 1-01 Table 2 FOODS AND BEVERAGES 2.1 1.Reference Materials and Collaborative Trials Only one paper appears in this section this year. The rush to produce RMs seems to have slowed. Pauwels et ul. (94/731) have published the results of a microhomogeneity study of a BCR candidate RM BCR CRM-422 Cod Muscle. The material was prepared by cryogrinding freeze-drying mixing and bot- tling and then the RM homogeneity examined by solid sam- pling Zeeman-effect ETAAS for Cd Fe Hg Pb and Zn. Element Matrix A1 Fruit juices A1 Waters A1 Fruit juices As As As As As As As As Vegetable oils Vegetables Fish shellfish Fish Oyster Foods Mineral waters Wine Technique; atomization; analyte form* Sample treatmentfcomments Reference AA;ETA;L 9411070 AE;ICP;L MS;ICP;L 9412099 9412 197 MS;ICP;L AE;ICP;L AA;ETA;L 94/22 14 9412538 9412804 AA;-;L The concentrations of Al P and Si were determined in 142 samples of apple grapefruit grape orange and pineapple juice groundwater and drinking water was investigated. 70% of the samples analysed had concentrations in the linear working range of 0.8-200 pg 1-' An on-line flow system was used for dilution and filtration of samples addition of 10 mmol 1-' Mg(NO,) as chemical modifier and final loading of solution into autosampler cups.Pyrolytic tubes with L'vov platforms were used KOH and analysed using ETAAS with a chemical modifier of 2% PdCl,. The LOD was 6.8 mg 1-' (in Chinese) 41 samples contained concentrations in excess of 9411 7 19 MS;ICP;L The suitability of using ICP-MS for analysis of 9412637 AA;ETA;L 9413282 The oils were saponified with 3 mol 1-' ethanolic As was determined by HG-ICP-AES.None of the 2 P8 8 - l Arsenobetaine arsenocholine arsenate arsenite dimethylarsenite monomethylarsonate and trimethylarsine oxide were separated and quantified by HPLC-ICP-MS at LODs of 10-50 ng g-' for all species except arsenobetaine for which the LOD was 360 ng g-'. The trimethylselenonium ion was also measured and used as an internal standard for the chromatography as the major species in cod dab haddock mackerel plaice and whiting. A lipid-bound arsenic species was putatively identified in the mackerel. Total As levels were also reported A dry ashing procedure was described utilizing 20% Mg(N03) with 2% MgO as ashing aid.The LOD was 0.1 pg g-' and the wavelength of measurement 193.696 nm Samples were pre-digested overnight at room temperature with HNO then treated with Mg(NO,) and HC10,. The resulting solution was evaporated to near dryness and after cooling mixed with HCl-H,SO (7 + 1) and 50% KI. Following extraction with CCl the organic phase was re-extracted with H20 and the resulting aqueous phase acidified evaporated and the residue analysed using ETAAS at 193.7 nm. Arsenic could be determined in samples containing as little as 1 ng g-' (in Russian) As and Se were determined using continuous flow HG with atomization occurring either in the conventional heated silica tube or in the cuvette of an ETAA spectrometer the latter following collection and thermal decomposition of the hydrides.Both elements had an LOD of 0.02 pg 1- Simple procedures for the analysis of wine were IJsing HPLC-ICP-MS arsenobetaine was identified described which yielded LODs for As and Pb of 6.6 and 15.5 ng 1-' respectively. Mg and Pd were used as chemical modifier AA;H y ;L 9412925 AA;ETAL 9412935 102 R Journal of Analytical Atomic Spectrometry April 1995 lf01.10Table 2 (continued) Technique; atomization; Element Matrix analyte form* As Chicken tissue MS;ICP;L Sample treatment/comments promoter 4-hydroxy-3-nitrophenylarsonic acid in tissue that had been enzymatically digested using trypsin. The quantification limit was 25 ng g-' A microwave-assisted distillation procedure was proposed for determining inorganic As at an LOD of 0.068 pg g-'. Using this procedure over- estimation of inorganic As may be possible since the authors did not demonstrate that reducible species such as dimethylarsinate were not also distilled Arsenic was determined following a multi-step dry ashing procedure yielding an LOD of 0.1 ng g-' A method using NH,NO,-Ba(NO,),-PdCl as chemical modifier was found to alleviate interferences from Na and sulfates. The LOD was 4 ng ml-' HPLC-ICP-MS was used to quantify the growth Reference 9412974 As Seafood products AA;H y;L AE;ICP;L 9412980 9413 170 94/c 3409 As As Orange juice Foods AA;Hy;L AA;ETA; L Foods Drinking water AA;Hy;L M S; I C P; L Various extraction procedures for solubilizing As in food without changing the speciation were considered concentrations present ranged from 10-925 pg 1-'.Ba was thought to exist either as a soluble inorganic form or in complexes with low molecular weight organic compounds Ba and I were determined with LODs of 0.2 ng 1- ' and 15 pg l-' respectively using ETAAS with laser desolvation for the Ba and intracavity laser spectroscopy for I. The laser was used to probe the vapour above liquids placed in a closed heated cell HN0,-H2S04 treated with 1 moll-' KI containing 10% ascorbic acid and analysed by HG-AAS at wavelengths of 223.1 and 306.8 nm for Bi and 217.6 nm for Sb. The LODs were 0.88 and 2.1 ng ml- for Bi and Sb respectively (in Chinese) P interference on Ca determinations was investigated and a number of releasing agents proposed (in Chinese) Samples were analysed using FI with Sr(NO,) as carrier.The LODs for Ca and Mg were 10 and 1 mg 1-' respectively (in Spanish) Cd was determined at a wavelength of 228.8 nm using pyrolytic cuvettes and L'vov platforms Cd was determined in the diet of the population of Seville Spain using microwave digestion with HNO followed by quantification using ETAAS with NH,H,PO as chemical modifier. The LOD was 2 ng g-' The analysis of Cd and Pb in animal tissues was critically assessed Cd and Pb were determined in samples grown alongside a major Libyan highway. Traffic emissions were believed to be the source of elevated levels of the elements found in all samples except potatoes coprecipitation with 20% Mg(N03),-20% NaOH (1 + 1). The LODS were 3.5 5 and 16.7 ng ml-' for Cd Cu and Pb respectively (in Chinese) Fresh non-homogenized liver was analysed directly by Zeeman-effect ETAAS.The results obtained using liquid standards agreed well with those obtained using conventional sample decomposition Ethylated Cd species were generated using sodium tetraethylborate. Using continuous flow vapour generation samples were introduced into an ICP-AE spectrometer giving an LOD of 0.4 ng ml-'. The vapour generation mechanism was discussed The merits of a mixed chemical modifier of Pd-tartaric acid were discussed when used in conjunction with a tungsten-foil platform. Standardless analysis gave an LOD of 0.3 pg Ba in Italian drinking water was investigated and Canned food samples were digested using Cd Cu and Pb were preconcentrated by 94/c3440 941893 As Ba AAETA;L Ba Biological materials water AA;Laser;L AAETA;L 9412929 Bi Foods AAHy;L 9413 158 Ca Foods AA;F;L 941948 Ca Milk AA;F;L 9411 126 Cd Cd Foods feed crops Foods AA;ETA;L AA;ETAL 941 108 2 941 1 203 Cd Cd Animal tissues Fruit vegetables A A;ETA; L A A;ETA; L 941 168 5 94/18 15 Cd Water AA;F air-C,H,;L 9412298 9412582 94/29 1 5 Cd Equine liver AA;ETA;S Cd Tea AE;ICP;G Cd Foods AA;ETA;L 9413 104 Journal of Analytical Atomic Spectrometry April 1995 Vol.10 103RTable 2 (continued) Technique; atomization; Element Matrix analyte form* Cd Rice AA;F;L Sample treatmentlcomments Reference A method for on-line preconcentration based on the sorption of soluble metal complexes on the walls of a knotted reactor was described. Thiourea and ascorbic acidlphenanthroline were used to overcome interferences from Cu and Fe respectively vegetable following digestion using 65% HNO in a PTFE bomb held at 110°C for 18 h from matrix effects and the choice of wash solutions were discussed in some detail On-line ASV was coupled to ICP-MS to determine 5zCr"' and "Vv and to eliminate 40Ar'2C+ and 3sC1160 + polyatomic interferences HPLC-FAAS the coupling achieved using a high pressure nebulizer.The wavelength was 357.8 nm and the LODs for a 100 pl injection were 0.03 and 0.02 pg ml-' for Cr"' and Crv' respectively Procedures for the FAAS determination of Cu and a fast furnace determination of Pb were given Reducing sugars were measured indirectly following their precipitation as Cu complexes by injecting Fehling's solution into a wine carrier which was directly aspirated into the AA spectrometer The feasibility and optimum conditions for the use of Amberlite XAD-16 to preconcentrate Cu Ni and Zn were investigated 94/C3408 Cr Cu and Zn were determined in 16 species of 9411204 Cr was speciated using FI-FAAS.Problems arising 941C1937 9412879 Cr"' and CrV' were speciated using coupled 9413 2 80 See Cr ref 9411204 AA;ETA;L AA;F;L AE;ICP;L Cr Cr Cr Cr Vegetables Drinking water Water Water AA;F;L MS;ICPL AA;F air-CzH,;L 941639 941703 c u c u Drinking water Wine AA;ETA;L AA;F;L AAF air-C2H2;L AA;-;L 941737 9411204 94/21 79 c u c u c u Tap water Vegetables Ginger AA;ETA;L AA,F;L AE;ICP;L AA;F;L Samples were digested in HN03-HC104 ( 10 + 2) H,P04 and KI added and Cu and Pb extracted using IBMK giving LODs of 7 and 30 pg kg-' respectively (in Chinese) chelates.Mixed solvents may lower density surface tension and viscosity thus increasing the efficiency of nebulization. Sample LOD was 0.44 ng ml-' Toluene-xylene (1 +4) was used to extract Cu See Cd ref. 9412298 Cu was determined directly in animal feed at an LOD of 10 pg 1-' without the use of a platform background correction or chemical modifiers Cu Fe and Zn were determined in lyophilized mussel tissue following microwave digestion at LODs of 4.8 1.2 and 19.5 pg 1-' respectively Haem and non-haem Fe were extracted using IBMK and speciated by selective extraction of non-haem Fe by water. Subsequent measurement was by ETAAS using discrete nebulization (in Japanese) An elaborate multi-step procedure for speciating haem and non-haem Fe was described based on selective retention on C cartridge columns (in Japanese) The method described in 941876 was applied by the same research group to the analysis of liver (in Japanese) See Cu ref.94/3341 Ge was extracted into butanol as a germanomolybdate complex and the organic phase analysed directly. Coating the cuvette with ammonium molybdate enhanced sensitivity. The LOD was 6 pg Hg was determined by continuous flow vapour trapping ETAAS using a gold-coated graphite tube and a sample insertion device. The LOD was 0.8 ng 1-1 (in Chinese) Samples were digested at 90°C in a Kjeldahl flask using HN03-H,SO,-HCl (4 + 2 + l) then oxidized by KMn04. Hg was generated by adding 12% SnC1 in HzS04. Results for a number of products were given (in Spanish) AA;F;L 9412250 c u Tap water c u cu 9412298 9412402 AA;F air-C,H,;L AA;ETA;S Water Animal feed AE;ICP;L 9413341 c u Mussels Fe Confectionary AA;ETAL 941876 Fe Foods 941898 Fe Liver AA;ETA;L 9411 708 Mussels Herbs AE1CP;L A A; ETA; L 9413341 941c3379 Fe Ge AA;ETAL 941720 Grain Fish fish products AA;CV;L 9411020 104 R Journal of Analytical Atomic Spectrometry April 1995 Vol.10Table 2 (continued) Technique; atomization; analyte form* AA;CV;L Element Hg Hg Hg I I I Mg Mn Mn Mn Mn Mo Ni P Pb Pb Pb Matrix Water Sample treatmentfcomments Anion and insecticide interferences on CVAAS Continuous flow CVAAS yielded an LOD of analysis for Hg were investigated 0.11 ng ml-'. The wavelength of measurement was 253.7 nm containing I- was found to overcome losses caused by the formation of the stable complex Hg142- which is not reduced by the usual agents It was reported that the use of HNO can lead to erroneously high recoveries if I is present as I-. The use of NH solution as diluent instead of HNO was recommended The use of Cr" as reducing agent in samples See Ba ref.9412929 Iodine was determined indirectly by measuring the absorbance arising from Hg in HgJ complexes formed during heating in the graphite furnace. The LOD using this approach was 3 pg 1-l See Ca ref. 9411 126 A slotted tube atom trap was described that gave signal enhancements of 3.4 fold over conventional FAAS. Ca Mg and Cr were reported to interfere (in Chinese) Plaque deposits arising from oxidized Mn on rice roots were studied using AAS Zeeman-effect STPF ETAAS in conjunction with a Mg-Pd chemical modifier was used to determine Mn in 36 Dutch whole milk powders An FI on-line solvent extraction preconcentration system was described.The LOD was 76 ng ml - ' (in Chinese) Samples were digested using HNO,-30% H202 and analysed for Mo and Se (in Chinese) See Cu ref. 941737 See Al ref. 9411719 See Cu ref. 941639 Reference 9411088 9412730 9413041 9412 5 54 9412929 94/29 5 8 9411 126 94/85 1 941875 9411863 9412895 941725 941737 9411 7 19 941639 941828 9411 190 941 168 5 9411814 9411 8 15 9412179 9412247 9412280 9412298 9412582 9412584 9412935 941C3387 94lC3406 Pork liver AA,CV;L Water AF;CV;L Milk powder MS;ICPL Biological materials water Tap waters AA,Laser;L AA,ETA;L Milk Beverages drinking water AA;F;L AA;F air-C2H2;L Rice Milk powder AA;-;L AA;ETA;L Water AA;-;L Rice sesame seeds Tap water Fruit juices Drinking water Bread flour wheat AA;ETA,L AA;-;L AA;-;L AA;ETA;L AA;F;L AA;-;- Pb was determined in the above samples produced in Jordan.Dry ashing was used to digest the samples. Mean Pb was below 1 pg kg-' in all cases (in Arabic) Pb was analysed at 283.3 nm using ETAAS equipped with pyrolytic tubes and L'vov platforms. With Pd-Mg(NO,) as chemical modifier an LOD of 0.9 pg 1-' was achieved The analysis of Cd and Pb in animal tissues was critically assessed After 15 months storage in Pb decanters cognac contained 800 pg 1-'. Two types of protected decanter showed no evidence of migration See Cd ref. 9411815 See Cu ref. 9412179 Sucrose solutions and high fructose corn syrup were prepared by diluting with an equal mass of 5% sub-boiling HNO then analysed using ETAAS with Mg(NO,) as chemical modifier Microwave digestion and dry ashing were compared for the preparation of samples arising during wine production.The results were similar for both of the procedures described (in French) See Cd ref. 9412298 See Cd ref. 9412582 An accurate and precise method yielding an LOD of 0.2 pg 1 - ' was described. The highest level found after analysing 10 different wines was 58.8 pg 1-' See As ref. 9412935 Pb and Sn were preconcentrated on and selectively desorbed from sulfydryl cotton giving LODs of 0.048 and 0.050 pg ml-' respectively Samples were saponified by ethanolic KOH and the resulting solutions analysed at 283 nm using ETAAS with PdCl as chemical modifier.The LOD was 0.7 pg 1-' Mussel AA;ETA;Sl Pb Animal tissues Pb Cognac AA;ETA;L AA;ETA;L Pb Fruit vegetables Pb Ginger Pb Sugar sugar syrups AA;ETA;L AA;F;L AAETA;L Pb Grapes and grape products AAETA;L Pb Water Pb Equine liver Pb Wine AA;F air-C,H,;L AA;ETA;S MS;ICP;L Pb Wine Pb Foods AA;ETA;L AA;Hy;L Pb Cooking oil AA;ETA;L Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 105RTable 2 (continued) Technique; atomization; analyte form* Element Matrix S Beer garlic Sample treatment/comments The role of S- and Se-containing compounds as flavourings and off-flavourings in beer and garlic was investigated using headspace GC-AED determination of fully oxidized S Glucosinolate content was measured uia the See Bi ref. 9413158 Sb was preconcentrated on activated alumina eluted in a minimum volume of 4 mol 1-' HC1 and analysed at 217.6 nm using ETAAS.This approach gave an LOD of 0.2 pg See Mo ref. 941725 HN0,-HC104 or HN03-HC104-H2S04 were found to be acceptable methods of digestion prior to HG-AAS analysis Samples were mineralized with HNO in a high pressure asher diluted mixed with Cu chemical modifier and analysed using Zeeman-effect ETAAS with a L'vov platform Ni(N03)2 and Ni(NO,),-Pd(NO,) were compared as chemical modifiers during Se measurement. The mixed modifier afforded the greater sensitivity (in Chinese) See S ref. 94JC1930 Egg white proteins were separated by ion exchange and fast protein LC and detected using FI-AAS. Flavoprotein was the richest Se-containing protein Slurries in 1 ml of acidified 0.005% Triton X-100 were prepared using an automated ultrasonic device.Using a mixed Mg-Pd modifier and isothermal atomization an LOD of 0.06 pg g-' was achieved See As ref. 94/2925 An FI system coupled to the autosampler cup was used for dilution and addition of chemical modifier The British Standard procedure for determination of Se in water was described. The method was based on boiling with H2S04-H202 cooling boiling with HC1 under reflux then analysis by HGAAS at 196 nm Silicone defoamer was identified in fruit juices using solvent extraction by IBMK followed by FAAS. The LOD was 1 mg I-' See Al ref. 9411719 Si was microwave-digested using HF. Addition of solutions of tertiary amines after the digestion reduced positive systematic errors. The LOD using this procedure was 75 ng ml-' Methyl derivatives of butyl- octyl- cyclohexyl- and octyltin were prepared using Grignard reactions and separated and quantified by GC-AAS A similar procedure to that described in 941756 was used to separate and quantify the same organotins using GC-AAS Sample 25 ml was mixed with 0.5% NH4CI-0.5% NH,SCN-50% C2H,0H (10 + 10+ 5) and analysed directly. The NH,' was claimed to increase sensitivity (in Chinese) Samples were digested with HNO HCl and H,S04 neutralized and diluted to 0.1 or 0.12 mol 1-' with HCl. KBH was used as the reducing agent (in Chinese) k trioctylphosphine oxide-coated tungsten probe was immersed in acidified sample rinsed with 2 moll-' HCl and transferred to the ETAAS tube.Ar was used as sheath gas and measurement was at 286.4 nm.The LOD was 0.4 ng ml-' and the RSD less than 5% (in Chinese) Homogenized samples were digested in HNO then HCl cooled diluted and filtered. Sn was determined in the filtrate at 189.989 nm Reference 94JC1930 9412541 9413 158 94/3340 941725 941863 9411678 9411785 94lC1930 9412 163 9412886 9412925 9412981 9413 1 5 1 941 108 1 9411719 9413262 941756 94/78 5 94/93 1 941 1229 941228 1 AE;-;G S Oilseed rape XRF;-;- AA;Hy;L A A;ETA;L Sb Foods Sb Tap water Se Rice sesame seeds Se Foods AA;ETA;L AA;H y;L A A; ETA; L Se Foods AA;ETA;L Se Drinking water Se Se Beer garlic Egg white Wheat flour AA;ETA;SI Se AA;Hy;L AA;ETA;L AAS;Hy;L Se Se Mineral Waters Fruit juices Water Se Fruit juices AA;F,N,O- C,H,;L AE;ICP;L AA;-;L Si Si Si Fruit juices Food Sn Sn Sn Edible oils AA;-;L Fruit juices AA;-;L Alcoholic beverages AA;F;L Tinned foods and beverages 1CP;Hy;L Sn Sn Waters AA;ETA;L Canned foods AE;ICP;L 9413 162 Sn 106R Journal of Analytical Atomic Spectrometry April 1995 b'ol.10Table 2 (continued) Element Matrix Technique; atomization; analyte form* Sn Tap water A A; ETA; L Sn Food V Water Zn Human milk Zn Tap water Zn Vegetables Zn Mussels AA;Hy;L MS;ICP;L AA;ETA;L AA;-;L AAETA;L AA;F;L AE;ICP;L AE;ICP;L MULTI-ELEMENT ANALYSIS Certified Reference Materials Various ( 5 ) Cod muscle AA;ETA;S Various Food CRMs AA;ETA;Sl MULTI-ELEMENT ANALYSIS Foods Various (8) Yoghurt AA-;L Various (4) Infant formulae Various Beverages foods Various Fruit vegetables Various (4) Salt Various Kitchen salt Various Kitchen salt Various (1 1) Rice wheat Various (7) Spanish honey AA;F;L .. _ _ _ 3 A A;ETA;S AE;arc;S AA;F air-C,H,;L S1MS;-;S SIMS;-;S AE;ICP;L AA;-;L Sample treatment/comments Following dilution to 2 mol 1-' with HCl samples underwent clean-up using a microcolumn packed with an anion-exchange resin. The retained chlorostannate complex was eluted using 0.05 moll-' HNO and swept into an HG system. The subsequently evolved hydrides were then preconcentrated in situ in a palladium-coated graphite tube held at 300°C. For a 10.7 ml sample the LOD was 0.05 pg 1-' See Pb ref. 94/C3387 See Cr ref. 94/2879 Milk was dry ashed at 400°C and the residue dissolved in 0.1 mol I-' HNO,. With measurement at 213.9 nm and a 10 ml injection the LOD was 122 nmol I-' See Cu ref. 941737 See Cr ref. 9411204 See Cu ref.94/3343 The microhomogeneity of a candidate CRM was assessed by solid sampling Zeeman-effect ETAAS measurement of five elements (Cd Fe Hg Pb Zn) 0.05% HNO containing 0.04% Triton X-100 and 5% HNO,. Slurries were homogenized manually or ultrasonically. Ultrasonic mixing and 5% HNO were found to improve stability Slurried CRMs were prepared in 0.05% HNO The concentration of eight nutritionally significant elements was measured in 80 samples of four commercial brands of yoghurt. Cu and Mn were reported to decline with length of storage (Ca Cu Fe K Mg Mn Na Zn) (in Spanish) An analytical procedure based on dry ashing was developed. Recoveries were 77-118% and the maximum RSD was 18% (Cu Fe Mn Zn) (in French) A review including 684 references on food analysis in China during the period 1990-91 (in Chinese) Metal content was found to increase in a range of plants when they were treated with metal containing pesticides.Samples were air dried ground digested in HNO,-30% H2O2 mixed with Pd solution graphite and HNO boiled to dryness and the residue further ground prior to analysis using the stated techniques determined by extraction using NaDDC (Cu Cd Pb Zn)(in Russian) secondary positive ion. Standards were prepared using fusion and freeze drying methods. The values obtained were in agreement with conventional methods and in the case of Li offered greater sensitivity than is attainable conventionally Elements in kitchen salt were determined as their secondary negative ion. Levels of F I and P were below the LODs attainable by conventional LC methods procedures for ICP-AES sample preparation were described (Ca Cu Fe K Mg Mn Mo Na Ni P Zn)(in Japanese) Analysis was conducted by calcination of the samples followed by dissolution of the ash in 0.1 mol 1-' HCl then measurement.Some elements were determined by LC (Ca Cu Fe K Mg Mn Na) Heavy metal impurities in cooking salt were Elements in salt samples were determined as their Open and closed vessel microwave digestion Reference 94lC3377 94/C3 3 87 9412879 941672 941737 9411 204 941334 1 94/73 1 9412 5 8 0 9411020 9411027 9411054 941 941 104 167 94/1436 941 1 43 7 9411708 941 1807 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 107 RTable 2 (continued) Element Matrix Technique; atomization; analyte form* Various (10) Human milk AE;ICP;L Various ( 5 ) Fats oils AA;ETA;L Various (6) Human milk Various (5) Foods milk powder Various (5) Vegetables AE;ICPL AE;ICP;L AA;F air-C,H,;Sl MULTI-ELEMENT ANALYSIS Beverages Various (8) Beverages water AA;F;L Various (16) Mineral waters AA;ETA;L Various (6) Water AA;-;L Various Beverages foods Various (6) Beer Various (4) Wine Various (18) Drinking water Various (13) Drinking water Various (4) Cow goat and ewe milk Various (20) Coffee Various (10) Human milk Various (6) Human milk .. _ _ _ 9 AE;ICP;L AA;ETA;L AE1CP;L AA;-;L AA:F;L AA;F;L AA;ETA;L AE;ICP;L AE;ICP;L Sample treatmentlcomments Reference L.ongitudina1 changes in trace element concentration in human milk were studied during the first 5 months of lactation. Cu Fe and Zn were reduced significantly on a daily basis Analysis of a range of fats and oils for As Cd Cr Pb and Sn showed that for refined oils most were below the LODs of 2 0.25 1 5 and 10 pg kg-' respectively.However abnormally high levels were found in some crude oils (in French) nonylphenol to 0.03% m/v then diluted 10-fold with HNO,. Matrix matched standards were used for calibration (Ca Cu Fe Mg P Zn) with LiBO at stepped temperatures up to 980°C. The results agreed well with those obtained using three other procedures Samples were dry ashed at 500 "C ground suspended in a 10% glycerol solution containing 1% HCl sonicated and then injected into an H,O carrier for measurement by FI-FAAS. La was added to the diluent used for Ca and Mg analysis (Ca Fe Mg Mn Zn) 9411867 94/21 19 Milk samples were emulsified using ethoxy Al Ba Si Sr and Ti were determined using fusion Metals were extracted and preconcentrated using a liquid membrane emulsion (Cd CO Cu Fe Mn Ni Pb Zn) Zeeman-effect ETAAS was used to determine 16 elements of biological significance in 96 samples of Italian mineral water.Results found using the Zeeman effect were contrasted with deuterium background correction Samples (11) were adjusted to pH 8-10 and stirred with amidoxime resin for 2 h. The resin was then removed by filtration and desorbed using 2 moll-' HNO,. The final solution was concentrated to 10 ml and analysed by AAS (Cd Co Cu Ni Pb Zn) A review including 684 references on food analysis in China during the period 1990-91 (in Chinese) Two digestion procedures were outlined; wet ashing with HN03-30% HzOz and a method using HNO and 0 Elemental content of 867 wines from 19 countries on sale in Switzerland was determined following acidification of the sample by HNO addition. The results were linked to colour source vintage and price of the wine (Cd Cu Pb Zn)(in German) Ultrasonic nebulization in conjunction with aerosol drying were used to improve sensitivity A survey of water samples in a district of India indicated that there was serious pollution of supplies e.g.Zn was above the WHO maximum admissible concentration in 65% of cases with one sample being 33 times above the limit. Cd Cu Fe and Mn also exceeded limits in some instances Seasonal changes in Cu Fe Mn and Zn in the milk from three species of Spanish animal were studied over 1 year Multi-element analysis and multivariate statistics were used in an attempt to assign geographical origin to green Arabica coffee samples.Mn was identified as the best indicator Longitudinal changes in trace element concentration in human milk were studied during the first 5 months of lactation. Cu Fe and Zn were reduced significantly on a daily basis nonylphenol to 0.03% m/v then diluted 10-fold with HNO,. Matrix matched standards were used for calibration (Ca Cu Fe Mg P Zn) Milk samples were emulsified using ethoxy 9412909 9413 13 5 9413 28 7 941730 941797 9411033 9411054 9411055 9411116 9411247 9411796 9411799 9411855 9411867 9412909 108R Journal of Analytical Atomic Spectrometry April 1995 Kd. 10Table 2 (continued) Element Matrix Technique; atomization; analyte form* Various (4) Tea leaf AE;ICP;Sl Various (16) Mineral waters Various Waters AE;ICP;L AE;ICP;L MS;ICP;L Various (6) Yellow rice AA,FL Various Teas AE;ICP;L MULTI-ELEMENT ANALYSIS Miscellaneous Various (10) Pollen AA;-;- XRD;-;- Various (8) Vinegar water AE;ICP;L Sample treatment/comments Commercial samples were ground and the < 80 mm fraction removed by a flow of C02 and subsequent trapping in a liquid N cooled tube.When measurement was performed against aqueous calibrations there was no difference between the results for the slurry and those obtained by conventional dry ashing and acid dissolution (Al Ba Mg Mn) A procedure for using Dowex cation-exchange resins for the selective preconcentration of REE present in mineral waters was described.The results were validated against those obtained using spectrophotometry The results of a Canadian co-operative study to estimate the precision and accuracy of private sector laboratories using the above techniques was described. The results were not particularly encouraging An analytical protocol for determining nutritional and toxic elements in yellow rice a flavouring ingredient in Chinese wine was described in some detail (Cu Fe Mg Mn Pb Zn) An open focused microwave digestion system using HNO followed by HC10 was outlined. The authors indicated that the results could be used to identify varietal origins Pollen collected from honeycombs was found to be an acceptable biomonitor of heavy metal pollution (in Czechoslovakian) The effect of 3 and 10% CH,COOH on selected analytical lines was measured as a function of incident power and carrier gas flow.Compromise conditions for vinegar analysis were recommended (Al Cd Cr Cu Fe Ni Pb Zn) Reference 94/29 14 94/29 1 7 94/3214 94/C3416 94/C3492 94/1656 9412398 LOCATION OF REFERENCES The full list of references cited in this Update have been published as follows 94/615-94/960 J. Anal. At. Spectrom. 1994,9(2) 73R-85R. 94/961-94/1264 J. Anal. At. Spectrom. 1994,9(4) 135R-146R. 94/1265-94/1830 J. Anal. At. Spectrom. 1994 9( 5) 149R-169R. 94/1831-94/2175 J. Anal. At. Spectrom. 1994 9(6) 189R-200R. 94/2176-94/2412 J. Anal. At. Spectrom. 1994 9(7) 203R-212R. 94/2413-94/2867 J. Anal. At. Spectrom. 1994 9( 8) 249R-265R. 94/2868-94/2994 J. Anal. At. Spectrom. 1994,9( lo) 267R-3 12R. 94/2995-94/3279 J .Anal. At. Spectrom. 1994,9( 1 l) 307R-318R. 94/3280-94/C3502 J. Anal. At. Spectrom. 1994 9( 12) 319R-366R. Abbreviated forms of the literature references quoted (excluding those to Conference Proceedings) are given on the following pages for the convenience of the readers. The full references names and addresses of the authors and details of the Conference presentations can be found in the appropriate issues of JAAS cited above. Abbreviated List of References Cited in Update 941637 Anal. Chim. Acta 1992,268 315.941639 At. Spectrosc. 1993 14 65. 94/64 At. Spectrosc. 1993 14 71. 941642 At. Spectrosc. 1993,14,80.94/650 Fresenius’ J. Anal. Chem. 1993 345 343. 941663 Talanta 1993 40 185. 941664 Talanta 1993 40 409. 941666 Fenxi Shiyanshi 1993 12 37.941672 Food Chem. 1992 44 213. 941674 J. Clin. Lab. Anal. 1992 6 264. 941676 J. Radioanal. Nucl. Chem. 1993,167,413.941678 Lihua Jianyan Huaxue Fence 1993 29 23. 941681 Lihua Jianyan Huaxue Fence 1993 29 49. 941685 Mikrochim. Acta 1993 110,41. 941686 Sci. Total Environ. 1992 125 15. 941696 Anal. Chim. Acta 1993 273 53. 941697 Anal. Chim. Acta 1993 274 275. 941703 Anal. Chim. Acta 1993 276 385. 941711 Analyst 1993 118 533. 941712 Analyst 1993 118 541. 94/720 Fenxi Huaxue 1993 21 303. 941726 Fenxi Huaxue 1993 21 492. 941727 Fresenius’ J . Anal. Chem. 1992 344 525. 941730 Fresenius’ J. Anal. Chem. 1993 345 467. 941731 Fresenius’ Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 109RJ. Anal. Chem. 1993 345 478. 941732 Fresenius’ J.Anal. Chem. 1993 345 482. 941736 Fresenius’ J. Anal. Chem. 1993 345 600. 941737 Fresenius’ J. Anal. Chem. 1993 345 755. 941739 J. Anal. At. Spectrom. 1993,8,79R. 941742 Spectrochim. Acta Part B 1993 48 387. 941756 Talanta 1993 40 299. 941767 Adv. Environ. Sci. Technol. 1992 25 89. 941769 Anal. Biochem. 1993 210 113. 941772 Anal. Lett. 1993 26 913. 941777 Anal. Lett. 1993 26 689. 941778 Anal. Lett. 1993 26 709. 941784 Appl. Environ. Microbiol. 1993 59 1274. 941785 Appl. Organomet Chem. 1992 6 579. 941797 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp. 209-226. 941798 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp.381-407.94/799 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp. 459-474.94/800 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp. 495-516.941801 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp. 517-537. 941802 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp. 539-570.94/803 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp 571-592.941804 A p p l . Zeeman Graphite Furn. At. Absorpt. Spectrom.Chem. Lab. Toxicol. eds. Minoia C. and Caroli S. Pergamon Oxford 1992 pp. 613-626.941806 Arch. Environ. Contam. Toxicol. 1993,24,421. 941807 Arch. Environ. Contam. Toxicol. 1993 24 494. 941808 Arch. Toxicol. 1993 67 200. 941810 Biochem. Pharmacol. 1993,45,1333.94/811 Biol. Trace Elem. Res. 1993 36 307. 941813 Biol. Trace Elem. Res. 1993 37 17. 941814 Bio. Trace Elem. Res. 1993 37 51. 941815 Biomater. Art$ Cells Immobilization Biotechnol. 1992 20 453. 941819 Bunseki 1993 1 65. 941824 Chin. Med. J. (Beijing Engl. Ed.) 1992 105 749. 941828 Dirasat-Univ. Jordan. Ser. B. 1991 18 89. 941829 Dtsch. Zahnaerztl. Z. 1992 47 526. 941830 Dtsch. Zahnaerztl Z. 1992 47 535. 941832 Eur. J. Pharmacol. Environ. Toxicol. Pharmacol. Sect. 1993 228 263. 941834 Exp. Toxicol. Pathol.1993 45 47. 941836 Fenxi Huaxue 1993,21,246.94/844 Guangpuxue Yu Guangpu Fenxi 1992 12(4) 63. 941846 Guangpuxue Yu Guangpu Fenxi 1992 12(4) 79. 94/847 Hejishu 1993 16 78. 941851 Hunan Daxue Xuebao 1992 19(4) 8. 94/856 J. Am. Water Works Assoc. 1993 85 77. 941861 J. Chin. Chem. SOC. (Taipei) 1993 40 33.941863 J. Food Compos. Anal. 1992,5,269.94/875 J. Plant Nutr. 1993 16 589. 941876 Jpn. J. Toxicol. Environ. Health 1993 39 114. 941877 Jpn. J. Toxicol. Environ. Health 1993 39 148. 941891 Neurotoxicology 1992 13 735. 941893 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 179. 941898 Nippon Shokuhin Kogyo Gakkaishi 1993 40 35. 941905 Nucl. Instrum. Methods Phys. Res. Sect. B 1993 B77 261. 941927 Sci. Total Environ. 1993 132 11. 941929 Sci.Total Environ. 1993,133 193.941931 Shipin Kexue (Beijing) 1992 156 41. 941932 Shokuhin Eiseigaku Zasshi 1992 33 586. 941935 Spectrosc. Lett. 1993 26 331. 941939 Trace Met. Enuiron. 1992 2 1. 941941 Trends Anal. Chem. 1993 12 41. 941947 Yingyang Xuebao 1992 14 422. 941948 Yingyang Xuebao 1992 14 430. 941950 Zavod. Lab. 1992 58(9) 3.941960 Zhongcaoyao 1993,24,19.94/979 Spectrochim. Acta Part B 1993 48 1291. 941983 Ann. Clin. Biochem. 1993 30 23. 941984 Ann. Clin. Biochem. 1993 30 142. 941985 Anal. Chem. 1993,65,2174.94/1006 Spectrochim. Acta Part B 1993 48 663. 94/1010 Spectrochim. Acta Part B 1993 48 723. 9411019 Alimentaria (Madrid) 1993 239 81. 9411020 An. Bromatol. 1992,44,45.94/1026 Analusis 1993 1 197. 9411027 Ann. Falsif. Expert. Chim.- Toxicol. 1992 85 381.9411031 Bull. Environ. Contam. Toxicol. 1992 49 388. 9411033 Chem. Anal. (Warsaw) 1992 37 641. 9411038 Chem. Listy 1992 86 531. 9411045 Chemosphere 1992 25 865. 9411046 Clin. Biochem. 1993,26,43.94/1047 Clin. Chem. (Washington DC) 1993 39 800. 9411054 Fenxi Shiyanshi 1992,11 83. 9411055 Food Chem. 1993 47,205. 9411056 GITFachz. Lab. 1992,36 812. 94/1058 Guangpuxue Yu Guangpu Fenxi 1992 12 101. 9411066 Guangpuxue Yu Guangpu Fenxi 1992,12,71.94/1069 Guangpuxue Yu Guangpu Fenxi 1992,12,99.94/1070 Guangpu Shiyanshi 1993 10 1. 9411073 Guangpu Shiyanshi 1993 10 24.9411075 Guangpu Shiyanshi 1993,10,40.94/1076 Guangpu Shiyanshi 1993 10 43. 9411081 J. AOAC Int. 1993 76 581. 9411082 J. Agric. Food Chem. 1992 40 1631. 9411085 J. Clin. Periodontol. 1993 20 366. 9411086 J.Dairy Sci. 1992 75 2176.9411088 J. Indian Chem. SOC. 1992,69,699.94/1094 Lab. Equip. Dig. 1993 31 31. 9411096 Lihua Jianyan Huaxue Fence 1993 29 96-97 100. 9411101 Labor-Med. 1992 15 275.9411103 Microchem. J. 1992,45,305.94/1104 Microchem. J. 1992 46 30. 9411105 Microchem. J. 1992 46 191. 9411106 Microchem. J. 1992 46 199. 9411107 Microchem. J. 1992 46 249. 9411116 Mitt. Geb. Lebensmitte-lunters Hyg. 1992 83 711. (Germany) 9411119 Nucl. Instrum. Methods Phys. Res. Sect B 1992 64 512. 9411126 Quim. Anal. (Barcelona) 1992 11 11.9411165 Zauod. Lab. 1992,58,23.94/1167 Zavod. Lab. 1992 58 23. 9411168 Zhongcaoyao 1993 24 131. 94/1188 Spectrochm. Acta. Part B 1993,48,1435.94/1189 Spectrochim. Acta Part B 1993 48 1445. 9411190 Analyst 1993 118 665. 9411203 Bull. Enuiron. Contam.Toxicol. 1993,50,417.94/1204 Bull. Enuiron. Contam. Toxicol. 1993 50 514. 9411205 Bull. Environ. Contam. Toxicol. 1993,50,547.94/1208 G. Ital. Chim. Clin. 1992 17 455. 9411214 Guangpuxue Yu Guangpu Fenxi 1992 12 91. 94/1229 Guangpuxue Yu Guangpu Fenxi 1993 13 55. 9411232 Guangpuxue Yu Guangpu Fenxi 1993 13 71. 9411233 Guangpuxue Yu Guangpu Fenxi 1993,13 85.9411242 Int. J. Environ. Anal. Chem. 1992,48,209.94/1246 LaborPraxis 1993 17 34. 9411247 LaborPraxis 1993 17 46. 9411252 Spectrosc. Eur. 1993 5 8 10 12-14. 9411264 Int. Lab. 1993 23 38. 9411281 Anal. Chem. 1993 65 2468. 9411294 Anal. Chim. Acta 1993 280 137. 9411321 Spectrochim. Acta Part B 1993 48 663. 9411325 Adv. Environ. Sci. Technol. 1992 25 77. 9411351 Biol. Mass Spectrom. 1993 22 441. 9411352 Biol.Trace Elem. Res. 1993 37 123. 9411353 Biomed. Res. Trace Elem. 1992 3 91. 9411369 Clin. Chem. (Washington D.C.) 1993 39 1650. 9411393 Inst. Phys. Conf. Ser. 1992 128 293. 9411407 J. Chromatogr. Biomed. Appl. 1993,615 83. 9411409 ,J. Environ. Sci. Health Part A 1993 A28,839.94/1416 J. Trace Microprobe Tech. 1992 10 109. 9411436 Nippon Kaisui Gakkaishi 1993 47 24. 9411437 Nippon Kaisui Gakkaishi 1993 47 30. 9411449 Nucl. Instrum. Methods Phys. Res. Sect. B 1993 B79 627. 9411487 Shipin Kexue (Beijing) 1993 159 ‘70 9411521 Second. Ion Mass Spectrom. SIMS 8 Proc. Int. Conf. 8th 1991 119. 9411527 Second. Ion Mass Spectrom. SIMS 8 Proc. Int. Conf. 8th 1991 269. 9411541 Second. Ion -Mass Spectrom. SIMS 8 Proc. Int. Conf. 8th 1991 661. 9411542 Second. Ion Mass Spectrom.SIMS 8 Proc. Int. Conf. 8th 1991 685. 9411543 Second. Ion Mass Spectrom. SIMS 8 .Proc. Int. Conf. 8th 1991,689.9411565 X-ray Spectrom. 1993 22 192. 94/1570 X-ray Spectrom. 1993 22 229. 9411587 X- ray Spectrom. 1993 22 332. 9411599 Nucl. Instrum. Methods Phys. Res. Sect. B 1993 82 129. 9411610 Anal. Chim. Acta 1993 278 189. 9411618 Analyst 1993 118 821. 9411635 Fresenius’ J. Anal. Chem. 1993 346 441. 9411643 Fresenius’ .I. Anal. Chem. 1993 346 689. 9411645 Fresenius’ J. Anal. Chem. 1993 346 833. 9411655 Acta Bioquim. Clin. Latinoam. 1992 26,205. 9411656 Acta Uniu. Palacki. Olomuc. Fac. Rerum Nut. 1991 104 157. 9411657 Adv. Biosci. (Oxford) 1993 87 259. 9411659 Alimentaria (Madrid) 1993 239 65. 94/1660 ’4limentaria (Madrid) 1993 241 35. 9411661 Am. Ind. Hyg. .4ssoc.J. 1993 54 454. 9411665 Anal. Lett. 1993 26 1997. 9411667 Anal. Sci. Technol. 1992 5 349. 9411669 Ann. Biol. Clin 1992 50 577. 9411670 Ann. Chim. (Rome) 1993 83 105. 941 1676 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 243. 9411677 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 257. 9411678 Appl. Zeeman Graphite Furn. At. 110R Journal of Analytical Atomic Spectrometry April 1995 Val. 10Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 279. 9411679 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 305.9411680 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 325.9411681 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 351.9411682 Appl.Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992,409.94/1683 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992,445.9411684 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992,475.9411685 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 593.9411686 Appl. Zeeman Graphite Furn. At. Absorpt. Spectrom. Chem. Lab. Toxicol. 1992 627.9411694 Baiqiuen Yike Daxue Xuebao 1993 19 133. 9411696 Biol. Neonate 1993 64 47. 9411697 Biol. Trace Elem. Res. 1993 37 91.9411699 Biomed. Res. Trace Elem. 1992,3 61.94/1700 Biomed. Res. Trace Elem. 1992 3 63. 9411701 Biomed. Res. Trace Elem. 1992 3 89. 9411702 Biomed. Res. Trace Elem. 1992 3 99. 9411703 Biomed. Res. Trace Elem.1992 3 181. 9411704 Biomed. Res. Trace Elem. 1992 3 205. 9411705 Biomed. Res. Trace Elem. 1992 3 209. 9411708 Biomed. Res. Trace Elem. 1992 3 219. 9411709 Biomed. Res. Trace Elem. 1992 3 221. 9411710 Biomed. Res. Trace Elem. 1992 3 225. 9411712 Biomed. Res. Trace Elem. 1992 3 237. 9411713 Biomed. Res. Trace Elem. 1992 3 243. 9411714 Biomed. Res. Trace Elem. 1992 3 255. 9411715 Biotechnol. Prog. 1993 9 526. 9411719 Can. J. Chem. 1993 71 769. 9411720 Cancer (Philadelphia) 1993 71 2962. 9411727 Clin. Biochem. 1993 26,43.94/1728 Clin. Chem. (Washington D.C.) 1993,39 1037. 9411729 Clin. Chem. (Washington D.C.) 1993 39 1662. 9411743 Environ. Health Perspect. 1993 99 149. 9411746 Environ. Res. 1993 61 212. 9411749 Exp. Mol. Pathol. 1993 58 215. 9411750 FEBS Lett. 1993 328 263.9411755 Fenxi Huaxue 1993 21 446. 9411759 Fresenius’ Environ. Bull. 1992 1 353. 9411760 Gaodeng Xuexiao Huaxue Xuebao 1993 14 621. 9411767 GIT Fachz. Lab. 1993 37 411. 9411776 Guangpuxue Yu Guangpu Fenxi 1992 12(5) 67. 9411778 Guangpuxue Yu Guangpu Fenxi 1992 12(5) 101. 9411785 Huanjing Baohu (Taipei) 1992 15 29. 9411789 Huanjing Wuran Yu Fangzhi 1992 14(5) 40. 9411793 IARC Sci. Publ. 1992 118 287. 9411795 Indian J. Environ. Prot. 1992 12 900. 9411796 Indian J. Environ. Prot. 1993 13 20. 9411797 inst. Phys. Conf. Ser. 1992 128 205. 9411798 Int. J. Environ. Health Res. 1993 3 99. 9411799 Int. J. Food Sci. Nutr. 1993 44 37. 9411801 Interfinish 92 Int. Congr. Surf Finish. 1992 3 1513. 9411804 J. Am. Coll. Nutr. 1993 12 31. 9411807 J. Apic. Res. 1992 31 65.9411813 J. Dent. Res. 1993 72 939. 9411814 J. Food Prot. 1992 55 806. 9411815 J. Food Saf. 1992 13 7. 9411833 Khim. Tekhnol. Vody 1993 15 255. 9411838 Laboratoriumsmedizin 1992 16 419. 9411842 Lihua Jianyan Huaxue Fence 1992 28 313. 9411843 Lithium 1993 4 115. 9411855 Mikrochim. Acta 1993 110 217. 9411856 Mitt. Klosterneuburg 1992 42 250. 9411859 MTA 1993 8 340. 9411861 Nahrung 1992 36 451. 9411862 Nahrung 1993 37 72. 9411863 Neth. Milk Dairy J. 1993 47 1. 9411865 Nippon Sanshigaku Zasshi 1993 62 310. 9411867 Nutr. Res. (N.Y.) 1993 13 499. 9411869 Ophthalmic Res. 1993 25 1. 9412077 Fr. Demande FR 2,679,656 (Cl. GUlN21/33) 29 Jan 1993 Appl. 91/9,630 25 Jul 1991; 16pp. 9412095 U.S.S.R. SU 1,778,647 (Cl. GOlN21/78) 30 Nov 1992 Appl. 4,868,807 25 Sep 1990. 9412099 Pertanika 1992 15 171.9412104 Pol. J. Environ. Stud. 1993 2 39. 9412109 Prog. CEin. Biol. Res. 1993 380 329. 9412110 Quim. Anal. (Barcelona) 1991 10 281. 9412111 Quim. Anal. (Barcelona) 1991 10 367. 9412114 Radiother. Oncol. 1993,27,46. 9412115 Reprod. Toxicol. 1993 7 225. 9412116 Rev. Cienc. Farm. (Sao Paulo) 1991 13 111. 9412117 Rev. Cienc. Farm. (Sao Paulo) 1991,13,127.94/2118 Rev. Esp. Cienc. Tecnol. Aliment. 1992 32 667. 9412119 Rev. Fr. Corps Gras 1993,40 19.9412120 Rev. Int. Oceanogr. Med. 1992 107. 9412121 Rev. SOC. Esp. Quim. Clin. 1992 11 142. 9412122 Riv. Vitic. Enol. 1992 45 29. 9412123 Rocz. Panstw. Zakl. Hig. 1992 43 333. 9412134 Shoyakugaku Zasshi 1993 47 70. 9412143 Tongji Daxue Xuebao 1992 20 109. 9412144 Turk. J. Chem. 1992 16 25. 9412162 Z . Lebensum.-Unters. Forsch. 1993 196 32. 9412163 Z. Lebensum.- Unters. Forsch. 1993 196 236. 9412171 Zhongguo Tiaoweipin 1992 10 28. 9412172 Zhongguo Yaoke Daxue Xuebao 1992,23,373.94/2173 Zhongguo Yike Daxue Xuebao 1993 22 113. 9412174 Zhongguo Zhongyao Zazhi 1993 18 223. 9412175 Zhonghua Yixue Jianyan Zazhi 1993 16 18. 9412179 J. Anal. At. Spectrom. 1993 8 61. 9412183 J. Anal. At. Spectrom. 1993 8 981. 9412185 J. Anal. At. Spectrom. 1993 8 995. 9412186 J. Anal. At. Spectrom. 1993 8 999. 9412187 J. Anal. At. Spectrom. 1993 8 1005. 9412197 J. Anal. At. Spectrom. 1993 8 1075. 9412204 J. Anal. At. Spectrom. 1993 8 1117. 9412207 J. Anal. At. Spectrom. 1993 8 261R 9412208 J. Anal. At. Spectrom. 1993,8 337R. 9412209 J. Anal. At. Spectrom. 1994 9 1. 9412211 J. Anal. At. Spectrom. 1994 9 11. 94/2213 J. Anal. At. Spectrom. 1994 9 23. 9412214 J. Anal. At. Spectrom. 1994 9 33. 9412244 Clin. Chem. 1992 38 1565. 9412245 Clin. Chem. 1993 39 155.9412246 Clin. Chem. 1993 39 883. 9412247 At. Spectrosc. 1993 14 85. 9412248 At. Spectrosc. 1993 14 90. 9412250 At. Spectrosc. 1993 14 99. 9412257 Analyst (London) 1993,118 1021.9412276 Zh. Anal. Khim. 1993 48 754. 9412280 Analusis 1993,21 249.9412281 Fenxi Ceshi Xuebao 1993 12 64. 9412283 Fenxi Yiqi 1993,2 22.9412295 LaborPraxis 1993,17,98.94/2298 Lihua Jianyan Huaxue Fence 1993,29 179.9412299 Microchem. J. 1993 48 184. 9412300 Nucl. Instrum. Methods Phys. Res. Sect. B 1992 68 269. 9412305 Zhongguo Yiyuan Yaoxue Zazhi 1993 13 169. 9412306 Br. J. Ind. Med. 1992 49 631. 9412307 Biochem. Biophys. Res. Commun. 1992 188 1010. 9412310 Pharm. Weekbl. Sci. Ed. 1992 14 321. 9412345 At. Spectrosc. 1993 14 141. 9412381 Nucl. Instum. Methods Phys. Res. Sect. B 1993 75 563. 9412394 J. Anal. At. Spectrom. 1994 9 79. 9412398 J. Anal. At. Spectrom. 1994 9 99. 9412400 J. Anal. At. Spectrom. 1994 9 111. 9412401 J. Anal. At. Spectrom. 1994 9 117. 9412402 J. Anal. At. Spectrom. 1994 9 125. 9412406 Fenxi Ceshi Xuebao 1993 12 67. 9412409 Fenxi Shiyanshi 1993 12 (4) 32. 9412410 Fenxi Shiyanshi 1993 12 ( 5 ) 51.9412411 Guangpuxue Yu Guangpu Fenxi 1993,13 110. 9412451 J. Sci. Food Agric. 1993 61 79. 9412496 Proc. Natl. Acad. Sci. U.S.A. 1993 90 2789. 9412505 Adv. X-Ray Anal. 1992,35B 1285.9412532 Anal. Chem. 1993,65 3501.9412533 Anal. Chem. 1993 65 3644. 9412536 Anal. Chim. Acta 1993 281 401. 9412540 Anal. Chim. Acta 1993 283 115. 9412543 Anal. Chim. Acta 1993 283 190. 9412554 Analyst (London) 1993 118 1015. 9412556 Analyst (London) 1993 118 1175. 9412569 Fenxi Huaxue 1993 21 601. 9412580 Fresenius’ J. Anal. Chem. 1993 346 1058. 9412582 Fresenius’ J. Anal. Chem. 1993 346 1068. 9412583 Fresenius’ J. Anal. Chem. 1993 347 58. 9412584 Fresenius’ J. Anal. Chem. 1993 347 119. 9412602 Australian Standard AS 4090-1993 13 Apr 1993 pp. 16. 9412603 Australian Standard AS 2411-1993 14 Jun 1993 pp. 16.9412613 Clin. Chem. ( Winston-Salem N.C.) 1993 39 1349. 9412614 Clin. Chim. Acta 1993 218 201. 9412615 Clin. Chim. Acta 1993 219 79. 9412624 Fenxi Shiyanshi 1993 12(4) 52. 9412625 Fenxi Shiyanshi 1993 12(4) 63. 9412626 Fenxi Shiyanshi 1993 12(4) 81. 9412637 Report 1991 RTVM-714301003; Order No. PB92-219534 42 pp. (Neth). Avail. NTIS. From Gov. Rep. Announce. index (U.S.) 1992 92(22) Abstr. No. 263,308. 9412650 Isotopenpraxis 1992 28 101. 9412673 inst. Phys. Conf Ser. 1992 128 275. 9412689 J. Chromatogr. 1993 654 261. 9412694 J. Korean Chem. SOC. 1993,37,800.94/2730 Mikrochim. Acta 1993,111,207.94/2795 Spec. Pub1.-R. SOC. Chem. 1993 124 (Applications of Plasma Source Spectrometry 11) 124.9412798 Tongweisu 1992,5,224. 9412800 Yaowu Fenxi Zazhi 1993 13 183. 9412801 Yaowu Fenxi Zazhi 1993 13 260. 9412804 Zavod. Lab. 1993 59(8) 19. 9412811 Anal. Chim. Acta 1993 284 181. 9412878 Anal. Chem 1994 66 1462. 9412879 Anal. Chem. 1994 66 1540. 9412886 At. Spectrosc. 1993 14 187. 9412895 Guangpuxue yu Guangpufenxi 1994 14( l) 94. 94/2896 Guangpuxue yu Guangpufenxi 1994 14(2) 103. 9412905 J. Anal. At. Spectrom. Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 1 1 1 R1994 9 177. 9412908 J. Anal. At. Spectrom. 1994 9 199. 9412909 J. Anal. At. Spectrom. 1994 9 205. 9412914 J. Anal. At. Spectrom. 1994 9 227. 9412915 J. Anal. At. Spectrom. 1994 9 231. 9412917 J. Anal. At. Spectrom. 1994 9 241. 94/2924 J. Anal. At. Spectrom. 1994 9 281. 9412925 J. Anal. At. Spectrom. 1994 9 285. 9412927 J. Anal. At. Spectrom. 1994 9 297. 9412928 J. Anal. At. Spectrom. 1994 9 303. 9412929 J. Anal. At. Spectrom. 1994 9 307. 9412934 J. Anal. At. Spectrom. 1994 9 337. 9412935 J. Anal. At. Spectrom. 1994 9 341. 9412944 J. Anal. At. Spectrom. 1994 9 393. 9412946 J. Anal. At. Spectrom. 1994 9 405. 9412951 J. Anal. At. Spectrom. 1994 9 437. 9412954 J. Anal. At. Spectrom. 1994 9 457. 9412958 J. Anal. At. Spectrom. 1994 9 483. 9412965 J. Anal. At. Spectrom. 1994 9 535. 9412973 J. Anal. At. Spectrom. 1994 9 611. 9412974 J. Anal. At. Spectrom. 1994 9 615. 9412980 J. Anal. At. Spectrom. 1994 9 651. 9412981 J. Anal. At. Spectrom. 1994,9,657. 9413014 Fresenius’ J. Anal. Chem. 1993,346( 6-9) 686.9413016 Fresenius’ J. Anal. Chem. 1993 346(6-7) 233. 9413026 J Anal. At. Spectrom. 1994 9 791. 94/3036 Talanta 1993 40(11) 1759. 9413041 Anal. Sci. 1993,9(6) 859.9413104 J. Anal. At. Spectrom. 1994 9 679. 9413106 J. Anal. At. Spectrorn. 1994 9 691. 9413122 J. Anal. At. Spectrom. 1994 9 797. 9413130 Anal. Chim. Acta 1994 285 359. 9413133 Anal. Chim. Acta 1993 283(2) 881. 9413135 Analyst 1994 119( l) 131. 9413142 Tulanta 1993 40( 12) 1927. 9413151 British Standard BS 6068 Section 2.45 1993 [IS0 9965 19931 15 Nov 1993. Pp. 10. 9413156 Fenxi Shiyanshi 1993 12 55. 9413157 Fenxi Shiyanshi 1993 12(6) 58. 9413158 Fenxi Shiyanshi 1993 12(6) 63. 9413163 J. AOAC Int. 1993 76(6) 1374. 9413164 J. Pharm. Biomed. Anal. 1993 11( 11-12) 1129. 9413170 Microchem. J. 1994 49(1) 20. 9413184 Anal. Chem. 1994 66( 6) 856. 94J3191 Akute Chronische Toxiz. Spurenelem. Jahrestag. Ges. Mineralstofe Spurenelem. 8th 1992 (Pub. 1993) 43-7. 9413192 Akute Chronische Toxiz. Spurenelem. Jahrestag. Ges. MineraEstoge Spurenelem. 8th 1992 (Pub. 1993) 61-4. 9413200 Clin. Chem. (Washington D.C.) 1994 40( l) 71. 9413213 J. Fr. Hydrol. 1992 23(1) 7. 9413256 J. Anal. At. Spectrom. 1994 9 945. 9413258 J. Anal. At. Spectrom. 1994 9 957. 9413262 J. Anal. At. Spectrom. 1994 9 981. 9413263 J. Anal. At. Spectrom. 1994 9 985. 9413269 J. Anal. At. Spectrom. 1994 9 1021. 9413277 J. Anal. At. Spectrom. 1994 9,1075.94/3280 Anal. Chem. 1 Oct 1993,65( 19) 2590.94/3282 Anal. Chem. 15 Nov 1994 65(22) 3331. 94/3287 Anal. Chim. Acta 15 Nov 1993 283( l) 393. 94J3300 Appl. Spectrosc. Oct 1993,47( lo) 1577.94/3301 Appl. Spectrosc. Oct 1993,47( lo) 1696. 9413311 Bunseki Kagaku Feb 1994,43(2) 105.9413340 Fresenius’ J. Anal. Chem. Feb 1994 348(5-6) 380. 9413341 Fresenius’ J. Anal. Chem. Feb 1994,348( 5-6) 390. 1 12 R Journal of Analytical Atomic Spectrometry April 1995 Vul. 10

ISSN:0267-9477    

DOI:10.1039/JA995100061R

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

References 95/C470-95/C.524 were presented at the Fourth International Conference on Plasma Source Mass Spectrometry University of Durham UK September 11-16 1994. 95fC470. 95JC471. 95/C472. 9 5fC473. 95/c474. 95fC475. 95/C476. 95JC477. 95fC478. 95fC479. 95JC480. 95fC48 1. 95fC482. 95/C483. 95/C484. Garcia Alonso J. I. Sena F. Arbore Ph. Rodriguez R. J. Koch L. Determination of major elements in nuclear samples by ICP-MS (Eur. Comm. JRC Inst. Transuranium Elements Postfach 2340 76125 Karlsruhe Germany). Turner P. J. Nicholls M. Some aspects of the analysis of solids using plasma mass spectrometer techniques (Finnigan MAT Ltd. Paradise Hemel Hempstead Herts UK HP2 4TG). Batey J. H. Liezers M. Tye C. H. Electron multiplier efficiency (Fisons Instruments Elemental Analysis Ion Path Road Three Winsford Cheshire UK CW7 3BX).Probst T. Rupprecht M. Partial least squares cali- bration for ICP-MS determinations applied to two model water systems (Inst. Radiochem. Tech. Univ. Munchen Walther-MeiBner-Str. 3 D-85748 Garching Germany). Stroh A. Briickner P. Vollkopf U. Recent advances in automation of ICP-MS analyses applying FIA sample introduction techniques (Bodenseewerk Perkin- Elmer GmbH Postfach 101761 D-88647 Uberlingen Germany). Houk R. S. Warren A. R. Alves L. A. Pang H.-M. Clemons P. S Minnich M. G. Experimental methods to improve precision and remove interferences in ICP-MS (Ames Lab. US Dept. Energy Dept. Chem. Iowa State Univ. Ames IA 50011 USA). Potter D. Kishi Y. Tsoupras G. Fundamental reduction of polyatomic interferences in ICP-MS (Hewlett-Packard 2850 Centerville Rd.Wilmington DE 19808 USA). Hutton R. C. Koller D. Sigsworth P. T. Flowing samples in liquid streams potentials for ICP-MS analysis (F.I. Elemental Analysis Ion Path Road Three Winsford Cheshire UK CW 3BX). Tanner S. D. Douglas D. J. Cousins L. M. Reduction of space charge effects in ICP-MS using a three aperture gas dynamic vacuum interface (SCIEX 55 Glen Cameron Rd. Thornhill Ontario Canada L3T 1P2). Jantzen E. Prange A. Multi-elemental speciation analysis using GC-ICP-MS (GKSS Res. Centre Inst. Phys. P.O. Box 1160 D-21494 Geesthacht Germany). Nicholls M. Turner P. J. Determination of low levels of uranium using electrothermal vaporization ICP-MS (Finnigan MAT Ltd. Paradise Hemel Hempstead Herts UK HP24TG). Komoda M.Chiba K. Uchida H. Determination of imrwrities on Si-wafer surface bv isotoDe dilution graphic separation and inductively coupled plasma mass spectrometric detection (Lab. Mater. and Nucl. Processes-Hot Lab. Paul Scherrer Inst. CH-5232 Villigen PSI Switzerland). 95/C485. Ruiz J. Geologic applications of inductively coupled plasma mass spectrometry (Dept. Geosci. Univ. Arizona Tucson AZ 85721 USA). 95/C486. Holland J. G. Lutz Th. M. Turner P. J. Laser ablation analysis of geological samples using IR and UV laser ablation techniques (Dept. Geol. Sci. Sci. Labs. South Rd. Durham City UK DH1 3LE). 95fC487. McCandless T. E. Ruiz J. Applications of laser ablation ICP-MS to problems in geochemistry (Dept. Geosci. Univ. Arizona Tucson AZ 85721 USA). 95fC488. Graham S. M.Sample preparation and determination of osmium by inductively coupled plasma mass spec- trometry (Mintek Private Bag ~3015 Randburg 2125 South Africa). 95/C489. McCandless T. Ruiz J. Ghazi A. M. In situ trace and rare earth elements (REE) determination in single fluid inclusions by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) (Dept. Geosci. Univ. Arizona Tucson AZ 85721 USA). 95/C490. Holland J. G. Eaton A. N. Turner P. J. Use of LA-ICP-MS for measuring partition coefficients at grain boundaries in igneous rocks (Dept. Geol. Sci. Sci. Labs. South Rd. Durham City UK DH1 3LE). 95,42491. G6mez Coedo A. Dorado Lbpez T. Features and evaluation of inductively coupled plasma mass spec- trometry in the quantitative determination of boron in steels using flow injection sampling system (Centro Nacl.Invest. Metal. (CSIC) Ave. Gregorio de Amo 8 28040 Madrid Spain). 95/C492. Greb U. Laser B. Jung G. New instrument approach to ultra-trace and high-performance ICP-MS (Finnigan MAT GmbH Barkhausenstr. 2 28197 Bremen Germany). 95/C493. Jakubowski N. Feldmann I. Tittes W. Stuewer D. Performance of a high-resolution ICP-MS prototype instrument (Inst. Spektrochem. Angew. Spektrosk. Postfach 10 13 52 D-44013 Dortmund Germany). 95/C494. Houk R. S. Chen X. Polyatomic ions as internal standards in ICP-MS (Ames Lab. US Dept. Energy Dept. Chem. Iowa State Univ. Ames IA 50011 USA). 95fC495. Stroh A. Vollkopf U. Alternative sample introduction techniques for ICP-MS-an overview (Bodenseewerk Perkin-Elmer GmbH Postfach 101761 D-88647 Uberlingen Germany). anhysis using ETV-ICP-MS (Achanced' Mater.& 95/C496. Tittes W. Feldmann I. Jakubowski N. Stuewer D. Technol. Res. Labs Nippon Steel Corp. 5-10-1 Application of desolvation and high mass resolution Fuchinobe Sagamihara Kanagawa Japan 229). for reduction of some selected spectral interferences in Mochizuki T. Sakashita A. Ishibashi Y. Laser ablation for trace elemental analysis of steels by ICP-MS (Mater. Characterization Res. Dept. Appl. Technol. Res. Center NKK Corp. Minamiwatarida- cho Kawasaki Japan 210). Nicholls M. Turner P. J. Whan D. A. Profiling of new and used palladium catalysts by ultra-violet laser ablation ICP-MS (Finnigan MAT Ltd. Paradise Hemel Hempstead Herts UK HP2 4TG). Hermann A. Kopajtic Z. Ledergerber G.Rollin S. Determination of rare earth elements in uranium materials using high-performance liquid chromato- ICP-MS (Inst. Spektrochem. Angew. Spektrosk. Postfach 101352 D-44013 Dortmund Germany). 95/C497. Jakubowski N. Stuewer D. Analysis of solid samples by plasma source mass spectrometry (Inst. Spektrochem. Angew. Spektrosk. Postfach 10 13 52 D-44013 Dortmund Germany). 95/C498. Soniassy R. Potter D. Kawabata K. Technical considerations in the development of a benchtop ICP-MS instrument ( Hewlett-Packard GmbH Hewlett-Packard Str. 8 7517 Waldbronn 2 Germany). 95/C499. Allott R. M. Miller P. D. Jones W. J. Mason R. S. Element analysis using concentration-modulated Journal of Analytical Atomic Spectrometry April 1995 VoZ. 10 1 13 R951c500. 95IC.501. 951c502.95lC503. 9 5/c504. 9 5 IC 50 5. 951C506. 951c507. 951C508. 95lC509. 951c510. 95/c5 1 1. 9 5/c5 12. 95/c5 13. 95/C514. 95/C5 15. absorption spectroscopy in a glow discharge source (Dept. Chem. Univ. Coll. Swansea Singleton Pk. Swansea UK SA2 8PP). Bogaerts A. van Straaten M. Gijbels R. Mathematical modelling of an analytical glow dis- charge (Univ. Antwerp Dept. Chem. Universiteitsplein 1 B-2610 Wilrijk Belgium). Tittes W. Feldmann I. Jakubowski N. Stuewer D. Greb U. Staats G. Analysis of steel reference samples with the prototype of a new double focusing ICP-MS instrument (Inst. Spektrochem. Angew. Spektrosk. Postfach 10 13 52 D-44013 Dortmund Germany). Mason R. S. Miller P. D. New ion source for glow discharge mass spectrometry (Dept. Chem. Univ. Coll. Swansea Singleton Pk.Swansea UK SA2 8PP). Schelles W. De Gendt S. Van Grieken R. Evaluation of the use of a secondary cathode for the analysis of different non-conductive sample types using glow discharge mass spectrometry (Univ. Antwerp (UIA) Dept. Chem. Universiteitsplein 1 B-2610 Antwerpen- Wilrijk Belgium). Vandecasteele C. Van den Broeck K. Leuven K. U. Environmental applications of ICP-MS (Dept. Chem. Eng. de Croylaan 46 3001 Heverlee Belgium). Beals D. M. Hayes D. W. Technetium-99 iodine-129 and tritium in the waters of the Savannah River Site (Savannah River Technol. Center Westinghouse Savannah River Co. Aiken SC 29808 USA). Zhang Y. Cox A. McLeod C. W. Ultra-trace determination of thorium in waters using microcolumn preconcentration and flow injection-ICP-mass spec- trometry (Environ.Res. Centre Sheffield Hallam Univ. Sheffield UK S1 1WB). Jones B. R. Analysis of marine sediments by ICP-MS (Ministr. Agric. Fish. and Food Fish. Lab. Remembrance Ave. Burnham-on-Crouch Essex UK CMO 8HA). Yamasaki SA. Tsumura A. Determination of ultra- trace elements in rain water by high-resolution ICP-MS (Natl. Inst. Agro-Environ. Sci. 3-1- 1 Kannondai Tsukuba Japan 305). Elwaer A. McLeod C. W. Drew P. Thompson K. C. Rapid sequential determination of bromate-bromide in waters by flow injection inductively coupled plasma mass spectrometry (Div. Chem. Sch. Sci. Sheffield Hallam Univ. Sheffield UK S1 1WB). Patriarca M. Lyon T. D. B. McGaw B. Reid M. Fell G. S. Assessment of nickel metabolism in humans using stable isotopes and ICP-MS (Dept.Clin. Biochem. 1st. Superiore di Sanita’ Rome Italy). Dunemann L. Begerow J. Greb U. Schoppenthau J. Sensitive and specific determination of elements and their species in biomatrices (Med. Inst. Umwelthyg. Heinrich-Heine-Univ. Dusseldorf Germany). Moens L. Dams R. Greb U. Jung G. Laser B. Application of high-resolution ICP-MS for the analysis of human serum (Lab. Anal. Chem. Ghent Univ. Proeftuinstraat 86 B-9000 Ghent Belgium). Angelini E. Bianco P. Palella C. Plassa M. Study of small mass variations of reference weights by ICP-MS (Dipt. Sci. Matel. Ing. Chim. Politecnic. Torino Italy). Stroh A. Bruckner P. Vollkopf U. Analysis of refractory sample matrices by ETV-ICP-MS (Bodenseewerk Perkin-Elmer GmbH Postfach 101761 D-88647 Uberlingen Germany). Forsyth R. S.Eklund U.-B. Spent nuclear fuel corrosion the application of ICP-MS to direct actinide analysis (Caledon-Consult AB Stenbrinken 7 S611 34 Nykoping Sweden). 951C516. 95lC517. 95/C518. 95/c5 19. 95IC520. 951c521. 951c522. 951c523. 951c524. 951525. 951526. 951527 951528. 951529. 45/530. Watson P. McLeod C. W. Novel approaches to selenium speciation in flow injection ICP-spectrometry (Div. Chem. Sch. Sci. Sheffield Hallam Univ. Sheffield UK S1 1WB). Houk R. S. Niu H.-g. Langmuir probe measurements of the ion extraction process in inductively coupled plasma mass spectrometry. 11. Measurements of floating voltage and rf voltage (Ames Lab. USDOE Dept. Chem. Iowa State Univ. Ames IA 50011 USA). Begerow J. Greb U. Dunemann L. Advantages of multi-element analysis in biological monitoring with HR-ICP-MS-first results and perspectives (Med.Inst. Umwelthyg Heinrich-Heine-Univ. Dusseldorf Dept. Anal. Chem. Auf ’m Hennekamp 50 40225 Diisseldorf Germany). Laser B. Rottmann L. Heumann K. G. HPLC coupled with a high-resolution ICP-MS for the determi- nation of elemental species (Finnigan MAT GmbH Barkhausenstr. 2 D-28 197 Bremen Germany). Stroh A. Vollkopf U. Evaluation of ICP-MS as a detector for elemental speciation (Bodenseewerk Perkin-Elmer GmbH Postfach 101761 D-88647 Uberlingen Germany). Batho A. Belmore R. J. Spark ablation of conducting solids into a plasma optical emission mass spectrometer (Thermo Electron Ltd. Warrington Cheshire UK). Tsumura A. Yamasaki SA. Ultimate detection limits obtained by high-resolution ICP-MS (Natl. Inst.Agro- Environ. Sci. 3- 1- 1 Kannondai Tsukuba Japan 305). Van den Broeck K. Vandecasteele C. Leuven K. U. Sample introduction techniques for the analysis of environmental samples by ICP-MS (Dept. Chem. Eng. de Croylaan 46 3001 Heverlee Belgium). Zilliacus R. Pajo L. Comparison of ICP-MS with neutron activation analysis for multi-element determi- nation in coal peat and biomass (Tech. Res. Centre of Finland (VTT) Chem. Technol. P.O. Box 1404 FIN-02044 VTT Finland). Weir D. G. Blades M. W. Characteristics of an inductively coupled argon plasma operating with organic aerosols. Part 1. Spectral and spatial obser- vations J. Anal. At. Spectrom. 1994 9 1311. (Dept. Chem. Univ. British Columbia Vancouver British Columbia Canada). Weir D. G. Blades M. W. Characteristics of an inductively coupled argon plasma operating with organic aerosols.Part 2. Axial spatial profiles of solvent and analyte species in a chloroform-loaded plasma J. Anal. At. Spectrom. 1994 9 1323. (Dept. Chem. Univ. British Columbia Vancouver British Columbia Canada). Castillano T. M. Giglio J. J. Evans E. H. Caruso J. A. Evaluation of low pressure inductively coupled plasma mass spectrometry for the analysis of gaseous samples J. Anal. At. Spectrom. 1994 9 1335. (Dept. Chem. Univ. Cincinnati Cincinnati OH 45221-0172 USA). Craig J. M. Beauchemin D. Univariate optimization of segmented-flow injection for inductively coupled plasma mass spectrometry J. Anal. At. Spectrom. 1994 9 1341. (Dept. Chem. Queen’s Univ. Kingston Ontario Canada K7L 3N6). Heumann K. G.Rottmann L. Vogl J. Elemental speciation with liquid chromatography-inductively coupled plasma isotope dilution mass spectrometry J. Anal. At. Spectrom. 1994 9 1351. (Inst. Inorg. Chem. Univ. Regensburg Universitatsstr. 3 1 D-93040 Regensburg Germany). Nam S.-h. Lim J.-s. Montaser A. High-efficiency nebulizer for argon inductively coupled plasma mass spectrometry J. Anal. At. Spectrom. 1994 9 1357. (Dept Chem. The George Washington Univ. Washington DC 20052 USA). 114R Journal of Analytical Atomic Spectrometry April 1995 Vol. 1095/53 1. 95/532. 95/533. 95 f534. 9 515 3 5. 951536. 9 515 3 7. 951538. 9 515 3 9. 95/540. 95/541. 95/542. Beary E. S. Paulsen P. J. Fassett J. D. Sample preparation approaches for isotope dilution inductively coupled plasma mass spectrometric certification of reference materials J.Anal. At. Spectrom. 1994,9 1363. (Natl. Inst. Stand. Technol. Gaithersburg MD 20899 USA). Argentine M. D. Barnes R. M. Electrothermal vaporization-inductively coupled plasma mass spec- trometry for the analysis of semiconductor-grade organometallic materials and process chemicals J. Anal. At. Spectrom. 1994 9 1371. (Dept. Chem. Lederle Graduate Res. Center Tower Univ. Massachusetts Box 34510 Amherst MA 01003-4510 USA). Campbell M. J. Demesmay C. 0116 M. Determination of total arsenic concentrations in bio- logical matrices by inductively coupled plasma mass spectrometry J. Anal. At. Spectrom. 1994 9 1379. (Service Central &Anal. CNRS Echangeur de Solaize BP 22 69390 Vernaison France). Takaku Y. Masuda K. Takahashi T.Shimamura T. Determination of trace silicon in ultra-high purity water by inductively coupled plasma mass spectrometry J. Anal. At. Spectrom. 1994 9 1385. (Anal. Res. Lab. Marubun Corp. 3-3-4 Minamisuna Kohto-ku Tokyo Japan 136). van Straaten M. Swenters K. Gijbels R. Verlinden J. Adriaenssens E. Analysis of platinum powder by glow discharge mass spectrometry J. Anal. At. Spectrom. 1994 9 1389. (Dept. Chem. Univ. Antwerp (UIA) Universiteitsplein 1 B-2610 Wilrijk-Antwerp Belgium). Pavski V. Chakrabarti C. L. Sturgeon R. E. Spatial imaging of the furnace atomization plasma emission spectrometry source J. Anal. At. Spectrom. 1994 9 1399. (Centre Anal. and Environ. Chem. Ottawa- Carleton Chem. Inst. Dept. Chem. Carleton Univ. 1125 Colonel By Dr. Ottawa Ontario Canada K1S 5B6).Hinds M. W. Brown G. N. Styris D. L. Mechanisms controlling the direct solid sampling of silicon from gold samples by atomic absorption spectrometry with electrothermal atomization. Part 1. Analyte migration to the solid surface J. Anal. At. Spectrom. 1994 9 1411. (Royal Canadian Mint 320 Sussex Dr. Ottawa Ontario Canada K1A OG8). Ebdon L. Goodall P. Hill S. J. Stockwell P. Thompson K. C. Approach to the determination of lead by vapour generation atomic absorption spec- trometry J. Anal. At. Spectrom. 1994 9 1417. (Anal. Chem. Res. Unit Dept. Environ. Sci. Univ. Plymouth Drake Circus Plymouth UK PL4 8AA). Cabrera C. Madrid Y. Camara C. Determination of lead in wine other beverages and fruit slurries by flow injection hydride generation atomic absorption spec- trometry with on-line microwave digestion J.Anal. At. Spectrom. 1994,9 1423. (Dept. Nutr. y Bromatol. Fac. Farm. Univ. Granada 18071 Granada Spain). Tahvonen R. Kumpulainen J. Determination of lead at low concentrations in food samples by electrothermal atomic absorption spectrometry J . Anal. At. Spectrom. 1994,9 1427. (Lab. Food Chem. Food Res. Inst. Agric. Res. Centre of Finland FIN-3 1600 Jokioinen Finland). Lespes G. Seby F. Sarradin P.-M. Potin-Gautier M. Application of experimental designs in optimization of a hydride generation quartz furnace atomic absorption spectrometry method for selenium determination J. Anal. At. Spectrom. 1994 9 1433. (Lab. Chim. Anal. Univ. Pau Ave. l’UniversitC 64000 Pau France). Marshall J. Carroll J. Crighton J.S. Barnard C. L. R. Atomic spectrometry update-industrial analysis metals chemicals and advanced materials J. Anal. At. Spectrom. 1994 9 319R. (ICI Wilton Res. Centre P.O. Box 90 Middlesbrough Cleveland UK TS90 8JE). 95/543. 951544. 951545. 951546. 951547. 951548. 951549. 951550 951551. 951552. Tao H. Miyazaki A. Decrease of solvent water loading in inductively coupled plasma mass spec- trometry by using a membrane separator J. Anal. At. Spectrom. 1995 10 1. (Natl. Inst. Resour. and Environ. Onogawa 16-3 Tsukuba Ibaraki Japan 305). Marawi I. Olson L. K. Wang J. Caruso J. A. Utilization of metallic platforms in electrothermal vaporization inductively coupled plasma mass spec- trometry J. Anal. At. Spectrom. 1995 10 7 . (Dept. Chem. Univ. Cincinnati Cincinnati OH 45221-0172 USA).Roehl R. Gomez J. Woodhouse L. R. Correction of mass bias drift in inductively coupled plasma mass spectrometry measurements of zinc isotope ratios using gallium as an isotope ratio internal standard J. Anal. At. Spectrom. 1995 10 15. (California Public Health Foundation 2151 Berkeley Way Berkeley CA 94704 USA). Uchino T. Ebihara M. Furuta N. Determination of rare earth elements in Precambrian sediments at Isua by inductively coupled plasma mass spectrometry J. Anal. At. Spectrom. 1995 10 25. (Dept. Chem. Fac. Sci. Tokyo Metropolitan Univ. Hachioji Tokyo Japan 192-03). Huang M.-f. Jiang S.-j. Hwang C.-j. Determination of arsenic in environmental and biological samples by flow injection inductively coupled plasma mass spec- trometry J. Anal. At.Spectrom. 1995 10 31. (Dept. Chem. Natl. Sun Yat-Sen Univ. Kaohsiung Taiwan China 804). Imai S. Okuhara K. Tanaka T. Hayashi Y. Saito K. Electrothermal graphite furnace atomic absorption signal for gold in organic matrices J. Anal. At. Spectrorn. 1995 10 37. (Dept. Chem. Joetsu Univ. Educ. Joetsu Nilgata Japan 943). Mahmood T. M. Qiao H. Jackson K. W. Physical behaviour of nickel and copper modifiers used in the determination of selenium by electrothermal atomic absorption spectrometry J. Anal. At. Spectrom. 1995 10 43. (Wadsworth Center for Lab. and Res. New York State Dept. Health and Sch. Public Health State Univ. New York P.O. Box 509 Albany NY Bulska E. Jgdral W. Application of palladium- and rhodium-plating of the graphite furnace in electro- thermal atomic absorption spectrometry J.Anal. At. Spectrom. 1995 10 49. (Dept. Chem. Univ. Warsaw 02-093 Warsaw Poland). Arruda M. A. Z. Gallego M. Valchrcel M. Automatic preparation of milk dessert slurries for the determi- nation of trace amounts of aluminium by electrothermal atomic absorption spectrometry J. Anal. At. Spectrom. 1995 10 55. (Dept. Anal. Chem. Fac. Sci. Univ. Cordoba E-14004 Cordoba Spain). Becker-Ross H. Florek S. Tischendorf R. Schmecher G. R. Flashlamp continuum AAS time resolved spectra J. Anal. At. Spectrom. 1995 10 61. (Inst. Spektrochem. angew. Spektrosk. Lab. spektroskop. Met. der Umweltanal. Rudower Chaussee 5 D- 12489 Berlin Germany). 12201-0509 USA). References 95/C553-95/C849 were presented at the 1994 Federation of Analytical Chemistry and Spectroscopy Societies (FACSS) S t .Louis MI USA October 2-7 1994. 95/C553. Platteau O. Two solvent system for determination of metallic elements in crude oils and petroleum products by flame AAS (Anal. and Evaluation Dept. INTEVEP S.A. Res. and Technol. Support Center of Petroleos de Venezuela S.A P.O. Box 76343 Caracas 1070A Venezuela). 95/C554. Salmon S. G. Williams M. C. Determination of silicon in petroleum products by ICP-AES (Texaco Inc. P.O. Box 509 Beacon NY 12508 USA). Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 115R95/C555. Brenner I. B. Zander A. Shkolnik J. Versatile calibration scheme for the analysis of petroleum products with ICP-AES (Ginzton Res. Center Varian Assoc. 3075 Hansen Way Palo Alto CA 94304 USA). 95/C556. Harness J.R. Tudeen V. A. Automated robotic workstation to prepare samples for wear metal analysis by atomic emission spectroscopy (Bohdan Automation Inc. Technol. Develop. 1500 McCormick Blvd. Mundelein IL 60060 USA). 95/C557. Platteau O. Direct determination of metallic elements in crude oils and petroleum products by GF-AAS using a two solvent mixture (Anal. Evaluation Dept. INTEVEP S.A. Res. and Technol. Support Center of PetrClleos de Venezuela S.A P.O. Box 76343 Caracas 1070A Venezuela). 95/C558. Botto R. I. Zhu J. J. Analysis of volatile petroleum/ petrochemical products using ICP-AES with ultrasonic nebulization and membrane desolvation (Exxon Res. and Eng. Co. Baytown Specialty Prod. P.O. Box 4255 Baytown TX 77522 USA). 95/C559. Moseley R. Z. Dulude G. R. Martin S.E. Direct determination of trace arsenic and lead in gasoline by GFAAS ( Thermo Jarrell Ash Corp. Franklin MA 02038 USA). 95/C560. Tahan J. E. Romero R. A Differential pulse anodic stripping voltammetric evaluation of total lead in anencephalic foetuses (Anal. Instrum. Lab. Fac. Sci. La Univ. del Zulia Maracaibo 4011 Venezuela). 95/C561. Shofran S. P. BOSS C. B. Lawless P. A. Reaction mechanisms and plasma diagnostics of a pulsed corona discharge (Dept. Chem. North Carolina State Univ. Raleigh N.C. 27695-8204 USA). 95/C562. Ug&re G. Salin E. D. Capsule based microwave digestion (Dept. Chem. McGill Univ. 801 Sherbrooke St. W. Montreal Quebec Canada H3A 2K6). 95/C563. Koirtyohann S. R. Yates D. Effects of saturation and blooming on a segmented CCD array detector (Dept.Chem. Univ. Missouri Columbia MO 65211 USA). 95/C564. Hill S. J. Ebdon L. Goodall P. Stockwell P. Generation of volatile organometallic compounds for on-line detection by atomic fluorescence spectroscopy (Dept. Environ. Sci. Univ. Plymouth Drake Circus Plymouth UK PL4 8AA). 95/C565. Scheie A. J. Holcombe J. A. Use of modifiers in direct ETV-MS (Dept. Chem. Biochem. Univ. Texas at Austin Austin TX 78712 USA). 95/C566. Hensman C. E. Rayson G. D. Applications of inductively coupled plasma axial viewing atomic absorption technique utilizing background correction (Dept. Chem. Biochem. New Mexico State Univ. Box 30001 Dept. 3C Las Cruces NM 88003 USA). 95/C567. Hareland W. A Monochromatic imaging camera for spectrally and spatially resolved pptical emission spec- troscopy (Sandia Natl.Labs. Albuquerque NM 87185 USA). 95/C568. Douthitt C. B. Allan M. New technology in high performance ICP-MS (9412 Rocky Branch Dr. Dallas TX 75243 USA). 95/C569. Alavosus T. J. Super-simultaneous ICP implications for the future of ICP spectroscopy (55 Cherry Hill Dr. Beverly MA 01915 USA). 95/C570. Jin L.-z. Shan X.-q. Chen B. Determination of carbon-bonded sulfur in soils by ICP-AES after hydri- odic acid reduction and hydrogen peroxide oxidation (Dept. Chem. Sci. Natl. Nat. Sci. Found. China 35 Huayuan Beilu East Gate Haidian District Beijing China 100083). 95/C571. Musselman B. Kubota E. Otsuka K. Performance characteristics of a new ICP high resolution mass spectrometer (JEOL USA Inc. 11 Dearborn Rd. Peabody MA 01960 USA). 95/C572.95/c573. 9 5/c574. 9 5/c575. 95/C576. 95/c577. 95/C578. 95/c5 79. 95/C580. 95/C58 1. 95lC582. 9 5/C5 8 3. 95/C 5 84. 95/C5 8 5. 95/C586. 9 SIC5 87. Wu S. Zhao Y.-h. Wittmeier A. Lucyk D. Dieken F. Interferences and their corrections for the determination of cadmium by inductively coupled plasma mass spectrometry (Environ. Chem. Alberta Environ. Centre P.O. Box 4000 Vegreville Alberta Canada T9C 1T4). Wiederin D. R. High throughput determination of metals in high solids samples using direct injection nebulization (CETAC Technol. 5600 S. 42nd St. Omaha NE 68107 USA). Sheier D. R. Micromethod for the determination of blood lead with matrix modification by graphite furnace atomic absorption utilizing a L'vov platform (MS Bellin Hosp. 215 N. Webster Ave. Green Bay WI 54301 USA).Epstein M. Smith S. Breen J. Slurry-sample intro- duction for rapid environmental assessments using graphite furnace atomic absorption spectrometry (Chem. Sci. Technol. Lab. Natl. Inst. Stand. Technol. Gaithersburg MD 20899 USA). Yehl P. M. Tyson J. F. Application of ICP atomic fluorescence spectrometry for speciation studies in complex matrices (Dept. Chem. Univ. Massachusetts Box 34510 Amherst MA 01003-34510 USA). Barnes K. W. Vollkopf U. Pruszkowski E. Beres S. Hergenreder R. New approaches to the analyses of biological matrices using inductively coupled plasma spectrometry (Perkin-Elmer Corp. 761 Main Ave. Norwalk CT 08859-0215 USA). Batey J. H. Liezers M. Tye C. T. Brown P. Electron multiplier efficiency (Fisons Instrum. Elemental Anal. Ion Path Road Three Winsford Cheshire UK CW7 3BX).Epstein M. S. Fassett J. D. Saraswati R. Torres R. A. Turk G. C. Certification of a mercury in water standard reference material (Chem. Sci. Technol. Lab. Natl. Inst. Stand. Technol. Gaithersburg MD 20899 USA). Batey J. H. Liezers M. Tye C. T. Brown P. Simulation of the quadrupole mass filter (Fisons Instrum. Elemental Anal. Ion Path Road Three Winsford Cheshire UK CW7 3BX). Amirav A. Dagan S. Electron impact hyperthermal surface ionization and fast GC-MS in supersonic molecular beams (Sch. Chem. Tel Aviv Univ. Tel Aviv 69978 Israel). Kawabata K. Yamanaka K. Sakata K. Study on reduction of polyatomic ions in ICP-MS by the Shield- Torch system (Yokogawa Anal. Systems Inc. 2-11-19 Naka-cho Musashino-shi Tokyo Japan 180).Wiedmann F. A. Wesdemiotis C. Emission spectra of collisionally activated ions (Chem. Dept. Univ. Akron Akron OH 44325-3601 USA). Krushevska A. Kotrebai M. Lasztity A. Barnes R. M. Application of tertiary amines in ICP-MS determination of arsenic and selenium in food and biological samples (Dept. Chem. Lederle GRC Tower Univ. Massachusetts Box 34510 Amherst MA Zhu J. J. Smith F. G. Reduction of polyatomic ion interferences in ICP-MS by ultrasonic nebulization and membrane desolvation (CETAC Technol. Inc. 5600 S. 42nd St. Omaha NE 68107 USA). Sparks C. M. Pinkston T. L. Holcombe J. A. Analyte distribution on the transport particles for ETV-ICP-MS (Dept. Chem. Biochem. Univ. Texas at Austin Austin TX 78712 USA). Hughes D. M. Grkgoire D. C. Chakrabarti C. I. Sturgeon R.E. Byrne J. P. Goltz D. M. Seawater (NASS-3) as a universal physical carrier for electro- thermal vaporization ICP mass spectrometry (Ottawa- 01003-4510 USA). 1 16 R Journal of Analytical Atomic Spectrometry April 1995 Wl. 10Carleton Chem. Inst. Dept. Chem. Carleton Univ. continuum source-array detection AAS (US Dept. Ottawa Ontario Canada K1S 5B6). Agric. Beltsville Human Nutr. Res. Centre Bldg. 161 BARC-East Beltsville MD 20705 USA). 95/C588. Fucsk6 J. Balazs M. K. Adsorption/desorption of metals within an ICP-MS (Balazs Anal. Lab. 252 95/C604. Histen T. E. Holcombe J. A New method for Humboldt Ct. Sunnyvale CA 94089-1300 USA). temperature control in ETAAS (Dept. Chem. Biochem. Univ. Texas at Austin Austin TX 78712 USA). 95/C589. Schleisman A. J. Bollinger D.Optimization of the ETV-ICP-MS (Texas Instrum. P.O. Box 655012 M/S 95/C605. de Loos-Vollebregt M. T. C. Calibration in Zeeman 301 Dallas TX 75265 USA). background correction (Delft Univ. Technol. Lab. 95/C590. Chen Y. Wu M.-g. Farnsworth P. B. Experimental studies of the effect of space charge on ion focusing in Mater. Sci. Rotterdamseweg 137 2628 AL Delft The Netherlands). an inductively coupled Plasma mass spectrometer 95/C606. Harnly J. M. Radziuk B. Effects of graphite furnace (Dept. Chem. Brigham Young Univ. Provo atomization conditions on simultaneous multielement UT 84602 USA). atomic absorption detection using a transversely heated 95/C591. 95/C592. 95/c593. 95/c594. 9 5/c595. 95/C596. 95fC597. 95/C598. Dziewatkoski M. P. Olesik J. W. Investigations into the ion sampling process oxide formation and matrix effects in inductively coupled plasma mass spectrometry (Lab.Plasma Spectrochem. Laser Spectrosc. and Mass Spectrom. Ohio State Univ. Dept. Geol. Sci. Scott Hall 1090 Carmack Rd. Columbus OH 43210 USA). Goldberg J. M. Minnick J. W. Electrical and optical characterization of a high-frequency capacitive dis- charge plasma gun atomic emission source (Dept. Chem. Univ. Vermont Burlington VT 05405-0125 USA). Goldberg J. M. Li FA. Characterization of a low- volume plasma gun/rf plasma source for atomic emis- sion spectroscopy (Dept. Chem. Univ. Vermont Burlington VT 05405-0125 USA). Starn T. K. Dearth L. L. Duan Y.-x. Jin Q.-h. Hieftje G. M. Mapping the microwave fields of a microwave plasma torch (Dept. Chem.Indiana Univ. Bloomington IN 47405 USA). Emily J. N. Goode S. R. Effect of design factors on fundamental characteristics of the tangential flow helium microwave-induced plasma torch (Univ. South Carolina Dept. Chem. Biochem. 730 S. Main St. Columbia SC 29208 USA). Pack B. W. Hieftje G. M. Investigations into the effects of mixed gases on an ICP-MIP tandem source for optical emission spectrometry (Dept. Chem. Indiana Univ. Bloomington Indiana 47405 USA). Akinbo 0. T. Carnahan J. W. Comparison of the performance of a membrane separator and condenser as an interface for coupling liquid chromatograph with low power helium microwave induced plasma (Dept. Chem. Northern Illinois Univ. DeKalb IL 601 15 USA). Tisdale R. C. Energy dispersive X-ray fluorescence spectroscopy as a new tool for process control in the cosmetics industry (Baird Corp.EDXRF Develop. Lab. 4101 Medical Pkwy. - Suite 108 Austin TX 78756 USA). 95/C599. Thomas C. L. Goode S. R. Oxgyen selectivity in the GC-MIP (Dept. Chem. Biochem. Univ. South Carolina Columbia SC 29208 USA). 95/C600. Styris D. L. Lamoureux M. M. Hutton J. C. Gordon R. L. Brown G. N. Palladium matrix modifier investigation by grazing incidence EXAFS (Pacific Northwest Lab. P.O.. Box 999 Richland WA 99352 USA). 95/C601. Groves R. Divoky P. Planer M. ICP monitoring of semi-conductor wastewater (Envirogard 1902 Swift Ave Clovis CA 93611 USA). 95/C602. Yuzefovsky A. I. Lonardo R. F. Slavin W. McCaffrey J. T. Michel R. G. Effect of spectral interferences on the linearization of calibration curves in Zeeman graphite furnace atomic absorption spectrometry (Dept.Chem. Univ. Connecticut Storrs CT 06269 USA). 95/C603. Harnly J. M. Radziuk B. Theoretical comparison of calibration curves for Zeeman self-reversed source and furnance (US Dept. Agric. Bdtsville Human Nutr. Res. Centre Bldg. 161 BARC-East Beltsville MD 20705 USA). 95/C607. Gilmutdinov A. Kh. Radziuk B. Sperling M. Welz B. Nagulin K. Yu Spatial distribution of radiant intensity from primary sources for atomic absorption spec- trometry (Dept. Appl. Res. Bodenseewerk Perkin- Elmer D-88647 Uberlingen Germany). 95/C608. GrCgoire D. C. Goltz D. M. Chakrabarti C. L. Byrne J. P. Mechanisms of atomization of uranium in electrothermal atomizers (Geol. Surv. Canada 60 1 Booth St. Ottawa Ontario Canada K1A OE8).95/C609. Redfield D. A. Mahon D. A Carter D. D. Maine S. A. Styris D. L. Mechanisms controlling lead atomization in ETAAS in the presence of aluminium and magnesium (Northwest Nazarene Coll. Nampa ID USA). 95/C610. Hunault P. Nelis T. Lemarchand A. Marcus R. K. Enhanced detector system for depth profile analysis by rf discharge atomic spectrometry full dynamic range on-the-fly (Instrum. SA Div. JOBIN YVON-BP 118 16-18 rue du Canal 91165 Longjumeau Cedex France). 95/C611. Molle C. Springael S. Wautelet M. Dauchot J. P. Hecq M. Mass spectrometry study of a magnetron planar glow discharge excited in the direct current mode (dc) and in the radiofrequency mode (rf) (Univ. Mons-Hainaut Ave. Maistrau 23,7000 Mons Belgium). 95/C612. Duckworth D. C. Barshick C. M.Smith D. H. McLuckey S. A. Yelton R. Hess K. R. Design and characterization of a new rf-glow discharge mass spectrometer (P.O. Box 2008 Chem. and Anal. Sci. Div. Oak Ridge Natl. Lab. Oak Ridge TN 95/C613. Marcus R. K. Harville T. R. Rf glow discharge atomic emission spectrometry for full solids coverage from precious metals to glasses (Dept. Chem. Clemson Univ. Clemson SC 29634-1905 USA) 95/C614. Heintz M. J. Myers D. P. Mahoney P P. Li G.q. Hieftje G. M. Characterization of an rf magnetron glow discharge source for time-of-flight mass spec- trometry (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). 95/C615. Marcus R. K. Shick C. R. Jr. Raith A. Hutton R. Comparison of rf-GD and LA-ICP-MS for the analysis of various sample types (Dept. Chem. Clemson Univ. Clemson SC 29634-1905 USA).95/C616. Chakrabarti C. L. Absalan G. Headrick K. L. Back M. H. Marcus R. K. Removal of matrix interferences by rf and dc sputtering in glow discharge atomic absorption spectrometry (Ottawa-Carleton Chem. Inst. Dept. Chem. Carleton Univ. Ottawa Ontario Canada K1S 5B6). 95/C617. King F. L. Meadows L. R. Steiner R. E. Optical and mass spectrometric investigations of pulsed rf glow discharge plasmas (Dept. Chem. West Virginia Univ. Morgantown WV 26506-6045 USA). 95/C618. Nygaard D. D. Krupa R. Owen E. Bulman F. Axial plasma observation for sensitivity enhancement in ICP- 37831-6375 USA). Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 1 17 R95/C6 19. 95/C620. 95/C621. 95/C622. 95/C623. 95/C624. 95/C625. 95/C626. 95/C627. 95/C628.OES (Baird Corp. 125 Middlesex Turnpike Bedford MA 01730 USA). Caruso J. A. Olson L. K. Giglio J. Interfacing gas chromatography with rf glow discharge mass spec- trometry (Dept. Chem. Univ. Cincinnati Cincinnati OH 45221 USA). Zhu J. J. Wiederin D. Bondarowicz J. Simultaneous determinations of total organic carbon with other elements by inductively coupled plasma spectrometry (CETAC Technol. Inc. 5600 S. 42nd Street Omaha NE 68107 USA). Fosdick L. E. Bhadha P. M. Analysis of hydrogen chloride gas after treatment with dryer resin for trace elemental contaminants by ICP-AES with ultrasonic nebulization (Hercules Incorp. Res. Center 500 Hercules Rd. Wilmington DE 19808-1599 USA). Smith F. G. Wiederin D. R. Gjerde D. T. Applications of an automated batch preconcentration/ matrix elimination system for ICP spectroscopy (CETAC Technol.Inc. 5600 S. 42nd St. Omaha NE 68107 USA). Hartshorne J. A. Olesik S. V. Olesik J. W. Inductively coupled plasma detection for carbon-based liquid chromatography (Dept. Chem. Ohio State Univ. 1090 Carmack Rd. Columbus OH 43210 USA). Ivaldi J. C. Barnard T. W. Axial viewing of the ICP for detection limit improvements (Perkin-Elmer Corp. 50 Danbury Rd. Wilton CT 06897 USA). Sun D. Ohlsson A. Sesi N. N. Hieftje G. M. Study of easily and non-easily ionizable element matrix effects in inductively coupled plasma atomic emission spec- trometry with a pre-evaporating device and a CCD imaging spectrometer (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). Caruso J. A. Elemental speciation a plus today-a mandate for the next century (Dept.Chem. Univ. Cincinnati Cincinnati OH 45221 USA). Vela N. P. Caruso J. A. Trace metal speciation via supercritical fluid techniques and plasma mass spec- trometry (Dept. Chem. Univ. Cincinnati Cincinnati Horlick G. Electrospray mass spectrometry the elemental analysis system for the next century? (Dept. Chem. Univ. Alberta Edmonton Alberta Canada T6G 2G2). OH 45221-0172 USA). 95/C629. Stewart I. I. Horlick G. Direct determination of solution ions by electrospray mass spectrometry (Dept. Chem. Univ. Alberta Edmonton Canada T6G 2G2). 95/C630. Marcus R. K. Radio frequency glow discharges for solid sample analysis what are the bounds? (Dept. Chem. Clemson Univ. Clemson SC 29634-1905 USA). 95/C631. Harville T. R. Marcus R.K. Radio-frequency glow discharge atomic emission spectrometry (rf-GD-AES) for bulk and depth-resolved elemental analyses (Dept. Chem. Howard L. Hunter Chem. Lab. Clemson Univ. Clemson SC 29634-1905 USA). 95/C632. Trowbridge N. R. George J. E. Thoma J. J. Performance evaluation of a new ICP-MS in a certified drinking water laboratory (Environ. Health Lab. 110 S. Hill St. South Bend IN 46617 USA). 95/C633. Chen Z. Doherty W. Gregoire D. C. Applications of laser ablation microprobe-inductively coupled plasma mass spectrometry (LAM-ICP-MS) to the in-situ trace element determination of minerals in geological samples (Geol. Surv. Canada 601 Booth St. Ottawa Ontario Canada K1A OE8). 95/C634. Mortlock R. A Froelich P. N. Determination of germanium by isotope dilution hydride generation inductively coupled plasma mass spectrometry ( Lamont-Doherty Earth Observatory Palisades NY 10964 USA).95/C635. 95/C636. 95/C637. 95/C638. 95/C639. 9 5/C 640. 95/C641. 95/C642. 95/C643. 95/C644. Tillotson B. D. Schleisman T. Trace analysis of ultra- pure H20 HF and NH,OH by concentration and DIN-ICP-MS (Texas Instrum. P.O. Box 655012 M/S 301 Dallas TX 75265 USA). Buckley B. Fang W. Johnson W. Jr. Speciation of metals in environmental samples by ion chromatogra- phy-inductively coupled plasma mass spectrometry (EOHSI Rutgers Univ. 681 Frelinghuysen Rd. Piscataway NJ 08855-1179 USA). Crews H. M. Baxter M. J. Strutt P. Hydride generation ICP-MS for total determinations of mercury selenium and arsenic in biological samples (MAFF CSL Food Science Lab.Norwich Res. Park Colney Norwich Norfolk UK NR4 7UQ). Rettberg T. M. Gilchrist G. F. R. Hutton R. C. ICP-MS routine analysis with mixed gases in argon plasmas (Fisons Instrum. 55 Cherry Hill Dr. Beverly MA 01915 USA). Nixon D. E. Moyer T. P. Screening for heavy metals in blood and urine with an inductively coupled plasma mass spectrometer (Metals Lab. Div. Clin. Biochem. Mayo Clinic Rochester MN 55905 USA). Granadillo V. A Romero R. A. Novel approach for total chromium determined by fast furnace program electrothermal atomization atomic absorption spec- trometry without analyte isoformation nor background correction (Anal. Instrum. Lab. Fac. Sci. Univ. del Zulia Maracaibo 401 1 Venezuela). Fender M. A. Butcher D. J. Determination of chloride by graphite furnace molecular absorption spectrometry with deuterium arc and Smith-Hieftje background correction (Dept.Chem. and Phys. Western Carolina Univ. Cullowhee NC 28723 USA). Smith C. M. M. Harnley J. M. Differentiation between inorganic and porphyrin bound iron using graphite furnace atomic absorption spectrometry (US Dept. Agric. Beltsville Human Nutr. Res. Center Beltsville MD 20705 USA). Delles J. B. Comparison of deuterium and Zeeman background corrections for graphite furnace analyses of total digestions and TCLP extractions of cemen- titious materials (Construction Technol. Labs. 5420 Old Orchard Rd. Skokie IL 60077 USA). Bradshaw D. K. Carnrick G. R. Trefry J. H. Metz S. Determination of trace metals in oceanic hydrothermal fluids (Perkin-Elmer Corp. 761 Main Ave.Norwalk CT 06859 USA). 95/C645. Shrader D. Flajnik C. Delles F. Background correc- tion in graphite furnace AAS-a review (Varian Assoc. 201 Hansen Ct. Ste. 108 Wood Dale IL 60191 USA). 95/C646. Littlejohn D. Hafid Belazi A. Davidson C. M. Sequential extraction of sediments for analysis by electrothermal atomic absorption spectrometry (Dept. Pure and Appl. Chem. Univ. Strathclyde 295 Cathedral St. Glasgow UK G1 1XL). 95/C647. Hinds M. W. Complimentary use of Massmann type and transversely heated graphite atomizers in determin- ing trace metals in gold by GFAAS (Royal Canadian Mint 320 Sussex Dr. Ottawa Ontario Canada K1A OG8). 95/C648. Katskov D. A. Schwarzer R. Marais P. J. J. McCrindle R. I. Furnace with graphite filter as an illustration of a new atomization concept (Dept.Chem. Phys. Technikon Pretoria Private Bag X680 Pretoria South Africa). 95/C649. Dulude G. R. Moseley R. Z. Pfeil D. L. Eliminating interferences in clinical applications of GFAAS (Thermo Jarrell Ash Corp. Franklin MA 02038 USA). !25/C650. Holcombe J. A. Jackson J. G. Fonseca R. W. Mass spectral studies of the thermal decomposition of metal nitrates (Univ. Texas Dept. Chem. Biochem. Austin TX 78712 USA). 1 18R Journal of AnaEytical Atomic Spectrometry April 1995 Vol. 1095/C651. 95/C652. 95/C653. 9 5/C 6 5 4. 95/C655. 95/C656. 9 5/C6 5 7. 9 5/C658. 95/C659. 95/C660. 95/C661. 95/C662. 95/C663. 95/C664. 95/C665. 95/C666. 9 5/C667. Jackson J. G. Scheie A. J. Holcombe J. A. Investigation of palladium nitrate modifiers by SIMS and TD-MS (Univ. Texas Dept.Chem. Biochem. Austin TX 78712 USA). Hinds M. Styris D. L. Brown G. N. Mechanisms of release of silicon from solution and from a solid gold matrix (Royal Canadian Mint 320 Sussex Dr. Ottawa Ontario Canada K1A OG8). Majidi V. Xu N. Molecular absorption of Group I11 elements in electrothermal atomizers (Dept. Chem. Univ. Kentucky Lexington KY 40506 UK). Byrne J. P. Hughes D. M. Chakrabarti C. L. GrCgoire D. C. Mechanisms of vaporization of tung- sten in electrothermal atomizers (Dept. Chem. Univ. Technol. Sydney P.O. Box 123 Broadway NSW 2007 Australia). Katskov D. A. Diffusion of molecular vapour through heated graphite (Dept. Chem. Phys. Technikon Pretoria Private Bag X680 Pretoria South Africa). Chakrabarti C. L. Goltz D. M. Hughes D. M. GrCgoire D. C. Byrne J.P. Mechanisms of atomiz- ation of boron in electrothermal atomizers (Ottawa- Carleton Chem. Inst. Dept. Chem. Carleton Univ. Ottawa Ontario Canada K1S 5B6). Welz B. Sperling M. Stauss P. Characteristics of longitudinally and transversely heated graphite tube atomizers (Dept. Appl. ..Res. Bodenseewerk Perkin- Elmer GmbH D-88647 Uberlingen Germany). Luan S. Pang €5.-m. Houk R. S. Fundamental and analytical studies of optical emission from the Mach disk extracted from an ICP (Ames Lab. US Dept. Energy and Dept. Chem. Iowa State Univ. Ames IA 50011 USA). Jackson K. W. Chen G. Modification by palladium in electrothermal atomizers the importance of hetero- geneous reactions ( Wadsworth Center Sch. Public Health State Univ. New York and New York State Dept. Health P.O.Box 509 Albany NY 12201-0509 USA). Browner R. F. Nebulization vaporization and ioniz- ation in ICP-AES and ICP-MS why haven’t we got it right yet and what can we do by the year 2000? (Sch. Chem. Biochem. Georgia Inst. Technol. Atlanta GA Wang L.q. May S. W. Browner R. F. Use of an oscillating capillary nebulizer (OCN) for micro-scale analysis of Se drug metabolites (Sch. Chem. Biochem. Georgia Inst. Technol. Atlanta GA 30332 USA). Hieftje G. M. Spectrochemical measurements for the 21st century (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). Myers D. P. Mahoney P. P. Li G. Hieftje G. M. Toward higher sensitivity in atomic TOFMS (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). Seace K. L. Platt D. Hurt S. G. Intelligent automation of the EPS QA/QC procedure for inorganic analyses (Hitachi Instrum.44 Old Ridgebury Rd. Danbury CT 06801 USA). Flajnik C. M. Delles F. Quality results for nutritional labelling by AA and ICP (Varian OSI 201 Hansen Ct. Suite 108 Wood Dale IL 60191 USA). Sanford C. L. Fernando R. Ennever F. K. Jones B. T. Determination of Pb in the blood of house painters by continuum source atomic absorption spec- trometry (Dept. Chem. Wake Forest Univ. Winston- Salem NC 27109 USA). Granadillo V. A. Tahin J. E. Romero R. A. Relationship between lead aluminium and vanadium levels and the arterial hypertension (Anal. Instrum. Lab. Fac. Sci. Univ. Zulia Maracaibo 401 1 Venezuela). 303 32-0400 USA). 95/C668. 95/C669. 95/C670. 95/C67 1. 95/C672. 95/C673. 95/C674. 95/C675. 95/C676. 95/C677. 95/C678. 95/C679.95/C680. 95/C681. 9 5/C 6 8 2. 95/C683. Smith F. G. Wiederin D. R. Mortlock R. Determination of rare-earth elements in geological and environmental samples using an automated batch preconcentration/matrix elimination system (CETAC Technol. 5600 S. 42nd St. Omaha NE 68107 USA). Cheam V. Lechner J. Lawson G. Sekerka I. Desrosiers R. Dissolved and particulate metals in lake water as directly determined by laser-excited atomic fluorescence (National Water Res. Inst. Aquatic Ecosystem Restoration Branch Box 5050 Burlington Ontario Canada L7R 4A6). Chen Z. Fryer B. J. Longerich H. P. Jackson S. E. Determination of precious metals in sulfide and magnet- ite minerals by inductively coupled plasma mass spectrometry after preconcentration using cation exchange (Geol.Surv. Canada 601 Booth St. Ottawa Ontario Canada KlA OE8). Hill S. J. Pitts L. Worsfold P. Selenium speciation- a flow injection approach employing on-line microwave reduction followed by hydride generationquartz fur- nace atomic absorption spectroscopy (Dept. Environ. Sci. Univ. Plymouth Drake Circus Plymouth UK PL4 8AA). Begley I. S. Sharp B. L. Protocol for high precision high accuracy isotope ratio measurement by ICP-MS (Dept. Chem. Loughborough Univ. Technol. Loughborough Leicestershire UK LE11 3TU). Hall E. S. Calello M. Cerrato P. Determination of lead isotope ratios in US postage stamps to chronicle lead pigment sources (Dept. Chem. Rutgers State Univ. New Jersey New Brunswick NJ 08903 USA). Lam J. W. H. McLaren J. W. Monodisperse dried microparticulate injector (MDM1)-the ultimate device for aqueous sample introduction? (Inst. Environ.Res. Technol. Natl. Res. Council Canada Ottawa Canada K1A OR9). Hutton R. C. Reed N. M. Microvolume analysis with high resolution ICP-MS (F.I. Elemental Anal. Ion Path Road Three Winsford Cheshire UK CW7 3BX). Tanner S. D. Can you have your cake and eat it too? Sensitivity and matrix effects in ICP-MS (SCIEX 55 Glen Cameron Rd. Thornhill Ontario Canada L3T 1P2). Denoyer E. R. Beres S. A Putting fundamentals into practice making advances in ICP-MS pay off for practical applications ( Perkin-Elmer Corp. 76 1 Main Ave Norwalk CT 06859-0215 USA). Lee S. C. Weeks S. Edelson M. C. Analytical application of electrothermal hollow cathode glow discharge spectrometer (ET-HCGDS) (Dept. Chem.Kyungnam Univ. Masan South Korea). Koppenaal D. W. Alexander M. L. Barinaga C. J. Smith M. R. Eiden G. C. Mendoza A. Fundamental studies in ICP-MS laser ablation and ion trap investigations (Pacific Northwest Lab. P.O. Box 999 MS P7-07 Richland WA 99352 USA). Schroeder S. Horlick G. Introduction of samples into a hollow cathode discharge using nebulization and laser ablation (Dept. Chem. Univ. Alberta Edmonton Alberta Canada T6G 2G2). You J.-z. DePalma P. Marcus R. K. Particle beam sample introduction into a hollow cathode discharge for atomic emission and mass spectrometry (Dept. Chem. Clemson Univ. Clemson SC 29634-1905 USA). Bengtson A. Mitchell J. Glow discharge optical emission spectrometry for quantitative depth profile analysis of nitrides and other wear-resistant hard coatings (Swedish Inst.Metals Res. Drottning Kristinas vag 48 S-11428 Stockholm Sweden). Winchester M. R. Salit M. L. Development and characterization of a system for glow discharge atomic Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 1 19R95/C684. 95/C685. 95/C686. 95/C687. 95/C688. 95/C689. 95/C690. 95/C691. 95/C692. 95/C693. 95/C694. 95/C695. 9 5/C696. 95/C697. 95/C698. 95/C699. 120R emission imaging of solid surfaces (Inorg. Anal. Res. Div. Natl. Inst. Stand. Technol. Gaithersburg MD 20899 USA). Leis F. New investigations on a microwave boosted glow discharge source (Inst. Spektrochem. Angew. Spektrosk. Bunsen-Kirchhoff-Str. 11 D-44139 Dortmund Germany). Raghani A. R. Smith B. W. Winefordner J. D. Influence of magnetic field on a microcavity hollow cathode discharge in atomic emission spectrometry (Dept.Chem. Univ. Florida Gainesville FL 3261 1 USA). Hutton J. C. Lamoureux M. M. Styns D. L. Gordon R. L. Conradson S. D. Hess N. J. Blanchard D. L. Chemical speciation of radioactive materials within Handford nuclear wastes (Pacific Northwest Lab. P.0 Box 999 Richland WA 99352 USA). Broekaert J. A. C. Hieftje G. M. Influence of operation parameters on the analytical figures of merit for different types of glow discharges (Univ. Dortmund Dept. Chem. D-44221 Dortmund Germany). Li G.q. Duan Y.-x. Hieftje G. M. Space-charge effects and ion distribution in plasma source mass spectrometry (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). Bakowska E. Potter D. Matsuzaki T. Software interface for a new inductively coupled plasma mass spectrometer (ICP-MS) (Hewlett-Packard Anal.Marketing Center 2850 Centerville Rd. Wilmington DE 19808 USA). Zhu J. J. Methods for delivering organic samples to nebulizers for trace element analysis by ICP spec- trometry (CETAC Technol. 5600 s. 42nd St. Omaha NE 68107 USA). Fulton G. Horlick G. AOTFs are they ready for atomic spectrometry? (Dept. Chem. Univ. Alberta Edmonton Alberta Canada T6G 2G2). Zhu J. J. Characterization of a micro laser ablation system for inductively coupled plasma mass spec- trometry (CETAC Technol. 5600 s. 42nd St. Omaha NE 68107 USA). Wiederin D. R. High throughput determination of mercury in waste water by direct injection nebulization ICP-MS (CETAC Technol. 5600 S. 42nd St. Omaha NE 68107 USA).Karanassios V. Zhang Z.-y. Wood T. Direct elemen- tal analysis of solid samples (Dept. Chem. Univ. Waterloo Waterloo Ontario Canada N2L 3G1). Wiederin D. R. Zhu J. Hydhde generation for interfacing microcolumn chromatography to ICP spec- troscopy for arsenic and selenium detection (CETAC Technol. 5600 S. 42nd St. Omaha NE 68107 USA). Chen Z. Fryer B. J. Longerich H. P. Ultra-trace rare’ earth element analysis of geochemical reference samples using a recycling nebulization system with a disposable spray chamber by inductively coupled plasma mass spectrometry (Geol. Surv. Canada 601 Booth Street Ottawa Ontario Canada K1A OE8). Wichems D. N. Jones B. T. Multi-element graphite furnace atomic absorption spectrometry with an induc- tively coupled plasma source (Dept.Chem. Wake Forest Univ. Winston-Salem NC 27109 USA). Nam S.-h. Lim I.-s. Montaser A. High efficiency nebulizer for argon inductively coupled plasma mass spectrometry (Dept. Chem. George Washington Univ. Washington DC 20052 USA). Castillano T. M. Caruso J. A. Performance of an ultrasonic nebulizer with organic solvents & plasma spectrometric detection (Univ. Cincinnati Dept. Chem. ML 172 Cincinnati OH 45221-0172 USA). 9 5/c700. 95/c701. 95/c702 95/c703. !)5/C704. 95/c705. 95/C706. 95/c707. 95/C708. 9 5/c709. 95/c7 10. 95/c711. 95/C712. 95/C7 13. 951C714. 95/C715. 9 5/C7 16. Williams M. C. Salmon S. G. Determination of boron in additives and lubricating oils (Texaco Inc. P.O. Box 509 Beacon NY 12508 USA). Lee C. E. Woosley R. S. Butcher D. J. Determination of aluminium calcium and magnesium in Fraser fir (Abies Fraseri) foliage and surrounding soil by atomic absorption spectrometry (Western Carolina Univ.Cullowhee NC 28723 USA). Thomas S. E. Sanford C. L. Jones B. T. Simple atomic absorption spectrometer using near-line back- ground correction (Dept. Chem. Wake Forest Univ. Winston-Salem NC 27109 USA). Wu M. Sulfur effect on accurate metal determinations by ICP-AES (Elf Atochem N.A. 900 First Ave. King of Prussia PA 19406 USA). Nair G. Williams J. C. Evaluation of the HCD as an emission source for non-metals (Dept. Chem. Univ. Memphis Memphis TN 38152 USA). Chen Y.-x. Williams J. C. Investigation of the evolution of the hollow cathode shape due to condition- ing by sputtering (Dept. Chem. Univ. Memphis Memphis TN 38152 USA).Mudroch A. Hall G. E. M. Cheam V. F. Arsenic speciation in lake sediment exposed to mine tailings disposal (Aquatic Ecosystem Restoration Natl. Water Res. Inst. Box 5050 Burlington Ontario Canada L7R 4A6). Cai X.-j. Williams J. C. Effective conditioning procedure for the hollow cathode in a pulsed discharge (Dept. Chem. Univ. Memphis Memphis TN 38152 USA). TahPn J. E. Granadillo V. A Romero R. A. Levels of Al Cu Fe Pb V and Zn in clinical samples and in standard reference materials evaluated by electrother- mal atomization atomic absorption spectrometry (Anal. Instrum. Lab. Fac. Sci. Univ. Zulia Maracaibo 4011 Venezuela). Hill S. J. Pitts L. Worsfold P. Determination of mercury in sediments using on-line pyrolysis preconcen- tration and atomic fluorescence detection (Dept.Environ. Sci. Univ. Plymouth Drake Circus Plymouth UK PL4 8AA). Gawalko E. Tkachuk R. Comparison of focused open and closed vessel microwave digestion procedures with conventional digestion procedures for trace element analysis of cereals (Grain Res. Lab. Canadian Grain Comm. 1404-303 Main St. Winnipeg Manitoba Canada R3C 3G8). Shan X.q. Wen B. Is palladium nitrate or a mixture of palladium and magnesium nitrate a more universal chemical modifier (Res. Center for Eco-Environ. Sci. Acad. Sin. P.O. Box 2871 Beijing China 100085). Karanassios V. Drouin P. Spiers G. Kellerman R. Correlation based signal processing in ICP spec- trometry (Dept. Chem. Univ. Waterloo Waterloo Ontario Canada N2L 3G1). Becotte-Haigh P. Ge H.-h. Tyson J. F. Denoyer E.R. Hinds M. W. Flow injection ICP-MS (Chem. Dept. Univ. Massachusetts Amherst MA 01003 USA). Autry H. A. Holcombe J. A. Separation and precon- centration of trace metals with poly-L-cysteine (Dept. Chem. Biochem. Univ. Texas at Austin Austin TX 78712 USA). Tu Q. Shan X.-q. Qian J. Ni Z.-m. Studies on trace metal redistribution during extraction of model soils by acetic acid/sodium acetate (Res. Center Eco- Environ. Sci. Acad. Sin. P.O. Box 2871 Beijing China 100085). Bakowska E. Wiederin D. R. Potter D. Trace metal analysis and speciation utilizing chromatographic Journal of Analytical Atomic Spectrometry April 1995 Vol. 1095/c717. 95/C718. 95/c719. 95/c720. 95/c721. 95/c722. 95/c723. 95/c724. 95/c725. 95/C726. 95/C727. 95/C728. 95/c729. 95/c730. 95/c73 1.sample introduction for inductively coupled plasma mass spectrometry (ICP-MS) (Hewlett-Packard Anal. Marketing Center 2850 Centerville Rd. Wilmington DE 19808 USA). Li L. Olson L. Caruso J. A. Lead speciation using capillary zone electrophoresis (CZE) with inductively coupled plasma mass spectrometry (ICP-MS) (Univ. Cincinnati Dept. Chem. ML 172 Cincinnati OH Zoorob G. Tomlinson M. Wang J.-s. Caruso J. A. Speciation of chromium employing a direct injection nebulizer (DIN) with inductively coupled plasma mass spectrometry (ICP-MS) (Univ. Cincinnati Dept. Chem. Mail Location 172 Cincinnati OH 45221 USA). Hill S. J. Ebdon L. Cairns W. R. L. Novel HPLC- ICP-MS interface for the determination of platinum species (Dept. Environ. Sci. Univ. Plymouth Drake Circus Plymouth Devon UK PL4 8AA).Bollinger D. Schleisman T. Preparation and analysis of high purity semiconductor chemicals by graphite furnace atomic absorption at the part per trillion level (Texas Instrum. P.O. Box 655012 M/S 301 Dallas TX 75265 USA). Skelly Frame E. M. Dorn S. B. LC-ICP applications in industrial R&D (GE Corp. Res. Develop. P.O. Box 8 Schenectady NY 12065 USA). Gilmutdinov A. Kh. Radziuk B. Sperling M. Welz B. Nagulin K. Yu. Spatially resolved detection of analyt- ical signals in graphite furnace atomic absorption spectrometry (Dept. Appl. Res. Bodenseewerk Perkin- Elmer D-88647 Uberlingen Germany). Patel B. M. Mansfield C. T. Determination of ultratrace elemental impurities in morpholine mono- ethanolamine and diethanolamine by graphite furnace atomic absorption spectroscopy (Texaco Inc.Res. Develop. Dept. P.O. Box 1608 Port Arthur TX 77641 USA). Shuttler I. L. Radziuk B. Carnrick G. Portala F. Tai Z. Leyrer M. Recent developments in ETAAS instrumentation (Bodenseewerk Perkin-Elmer GmbH Postfach 10 17 51 D-88647 Uberlingen Germany). Jackson K. W. Mahmood T. M. Reduction of chloride interference in electrothermal AAS (Wadsworth Center Sch. Public Health State Univ. New York P.O. Box 509 Albany NY 12201-0509 USA). Littlejohn D. Belazi A. H. Study of the effects of matrix modifiers for removal of chloride interferences in the analysis of seawater by ETAAS (Dept. Pure Appl. Chem. Univ. Strathclyde 295 Cathedral St. Glasgow UK G1 1XL). Miller-Ihli N. J. Routine GFAAS solids analyses facts fallacies and fantasies (US Dept.Agric. Beltsville Human Nutr. Res. Center Food Composition Lab. Beltsville MD 20705 USA). Sturgeon R. E. GrCgoire D. C. Ding W.-w. Applications of in-situ hydride techniques with the graphite furnace (Inst. Environ. Res. Technol. Natl. Res. Council Canada Ottawa Canada K1A OR9). Falk H. Analysis of micro-amounts with furnaces the contributions of Klaus Dittrich to trace analysis (Spectro Anal. Instrum. Boschstr. 10 D-47533 Kleve Germany). Carnahan J. W. Brandl P. G. Fu Y.-m. Integrated approach to the investigation of monomer ion induced charge transfer in plasma spectroscopy (Dept. Chem. Northern Illinois Univ. DeKalb IL 60115 USA). Duarte M. W. Rayson G. D. Development of an alternative method for determining temperature in an argon inductively coupled plasma (ICP) (Dept. Chem.Biochem. New Mexico State Univ. Box 30001 Dept. 3C Las Cruces New Mexico 88003 USA). 45221-0172 USA). 95/c732. 9 5/c 7 3 3. 9 5/c7 34. 9 5/c73 5. 95/C736. 9 5/c737. 9 5/C738. 95/c739. 95/c740. 95/c741. 95/c742. 95/c743. 95/c744. 95/c745. 95/C746. 95/c747. 9 5/c 74 8. Sturgeon R. E. Luong V. T. Marcus R. K. Langmuir probe diagnostics of the FAPES plasma (Inst. Environ. Res. Technol. Natl. Res. Council Canada Ottawa Canada K1A OR9). Marcus R. K. Harville T. R. Rf glow discharge atomic emission spectrometry can it replace the arc and spark? (Dept. Chem. Clemson Univ. Clemson SC Blades M. W. LeBlanc C. Rahman M. Emission and absorption features of furnace atomization plasma excitation sources (Univ. British Columbia Dept. Chem. Vancouver British Columbia Canada V6T 1Z1).Liang D. C. Leung K. Yu C.-b. Gauley W. Optimization and characterization of plasma graphite furnace emission spectrometry using Ar and He gases (Aurora Instrum. 191 W. 6th Ave. Vancouver British Columbia Canada V5Y 1K3). Broekaert J. A. C. Pollmann D. Pilger C. Leis F. Tschopel P. Elimination of spectral interferences in ICP-MS of ceramic samples (Univ. Dortmund Dept. Chem. D-44221 Dortmund Germany). Williams J. C. Plasma characteristics in the mini- hollow cathode emission source (Dept. Chem. Univ. Memphis Memphis TN 38152 USA). Sadler D. A. Littlejohn D. Perkins C. V. Compensating for manufacturing tolerances and drift in an optical emission spectrometer with array detection (Dept. Pure Appl. Chem. Univ. Strathclyde Glasgow UK).Kinzer J. A Olesik S. V. Laming L. A. Olesik J. W. Elemental speciation using capillary electrophor- esis inductively coupled plasma emission and mass spectrometry (Dept. Chem. Ohio State Univ. 1090 Carmack Rd. Columbus OH 43210 USA). Sappey A. D. Hyatt D. Sagan F. Sensitive detection of trace metals on fly ash by ICP-atomic emission spectroscopy (ADA Technol. 304 Inverness Way S. Suite 110 Englewood CO 80112 USA). Carney K. P. Development of a real-time monitor for metallic off-gases emitted from hazardous mixed waste processing systems (Argonne Natl. Lab. W. P.O. Box 2528 Idaho Falls ID 83403 USA). Schlager R. J. Durham M. D. Marmaro R. W. Monitoring total and speciated mercury by ultraviolet absorption spectroscopy (ADA Technol. 304 Inverness Way S. Suite 110 Englewood CO 80112 USA).Chisholm W. P. Review of METC’s continuous process monitoring devices for application to high temperature and pressure fossil fuel process streams (US Dept. Energy Morgantown Energy Technol. Center Morgantown WV 26507-0880 USA). Seltzer M. D. Continuous emissions monitor for airborne metals (Chem. Div. Res. Dept. Naval Air Warfare Center Weapons Division China Lake CA 93555 USA). Peng L. W. Flower W. L. Hencken K. R. Johnsen H. A. Renzi R. F. French N. B. Ottesen D. K. Laser-spark spectroscopy for continuous monitoring of metal emissions (Sandia Natl. Labs. Livermore CA Broekaert J. A. C. Siemens V. Klockow D. Optimization of low power MIP discharges for the monitoring of toxic metals in gases (Univ. Dortmund Dept. Chem. D-44221 Dortmund Germany).Meyer G. A. Continuous monitoring for metals in stationary stack emissions (Battelle Memorial Inst. 505 King Ave. Columbus OH 43201 USA). Savage J. M. Robertson J. D. Majidi V. Zhang W. Novel preconcentration technique for the PIXE analysis 29634-1905 USA). 94551-0969 USA). Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 121 Rof water (Element Anal. Corp. 1696 Capital Cr. S.W. Tallahassee FL 32310 USA). 95/C749. Eyler J. R. Development and application of new ionization sources for elemental analysis by FTMS (Dept. Chem. Univ. Florida P.O. Box 1 17200 Gainesville FL 3261 1-7200 USA). 95/C750. Robinson L. Dyer F. F. Nuclear methods of analysis in the advanced neutron source (Oak Ridge Natl. Lab. P.O. Box 2008 Oak Ridge TN 37831-6128 USA).95/C751. Chen H. Sharov V. A Mildner D. F. R. Downing R. G. Paul R. L. Lindstrom R. M. Zeissler C. J. Xiao Q.-f. Focusing cold neutrons using capillary optics for analytical nuclear methods (Chem. Sci. Technol. Lab. Natl. Inst. Stand. Technol. Gaithersburg MD 20899 USA). 95/C752. Koons R. D. ICP-MS or ETA-AA. analysis of individual carpet fibres (Forensic Sci. Res. Unit FBI Academy Quantico VA 22135 USA). 95/C753. Clark D. D. Hossain T. Z. Elemental analysis with a cold neturon irradiator (Cornell Univ. Ward Lab. Ithaca NY 14853-7701 USA). 95/C754. Vollkopf U. Bruckner P. Potentials and limitations of solid sampling analysis with slurry sampling ETV- ICP-MS (Bodenseewerk Perkin-Elmer GmbH D-88647 Uberlingen Germany). 95/C755. Morales-Rubio A. Woods G. Mena M.L. McLeod C. W. On-line microwave digestion and ICP spectro- chemical analysis of environmental materials (Environ. Res. Centre Div. Chem. Sheffield Hallam Univ. Sheffield UK S1 1WB). 95/C756. Pinkston T. Sparks C. Multielement determination of trace metal contaminants on silicon wafers by ETV- ICP-MS FI-ICP-MS and GFAAS after vapour phase decomposition (SEMATECH 2706 Montopolis Dr. Austin TX 78748 USA). 95/C757. Watling R. J. Herbert H. K. Comparison of GF-AAS ICP-AES and ICP-MS for the determination of gold platinum and palladium in the geochemical exploration for precious metal deposits (Chem. Centre (WA) 125 Hay St. East Perth Western Australia 6004). 95/C758. Richner P. Wanner B. Determination of boron isotope ratios and rare earth elements by ETV-ICP-MS (Swiss Federal Lab.Mat. Testing and Res. Ueberlandstr. 129 CH-8600 Duebendorf Switzerland). 95/C759. Hutton R. C. Sigsworth P. T. Barron M. Problem solving with ETV-ICP-MS (F.I. Elemental Anal. Ion Path Road Three Winsford Cheshire UK CW7 3BX). 95/C760. Grkgoire D. C. GrCgoire C. E. ETV-ICP-MS us. GFAAS to atomize or not to atomize? ... that is the question! (Geol. Surv. Canada 601 Booth St. Ottawa Ontario Canada K1A OE8). 95/C761. Beres S. A. Graphite furnace as a chemical reactor in ICP-mass spectrometry; (Perkin-Elmer Corp. 761 Main Av. Norwalk CT 06859-0215 USA). 95/C762. Sundin N. G. Tyson J. F. McIntosh S. Hanna C. P. Determination of selenium in urine by flow injection hydride generation atomic absorption spectrometry (Dept. Chem. Univ. Massachusetts Box 34510 Amherst MA 01003-4510 USA).95/C763. Hanna C. P. McCaffrey J. T. Using flow injection flame atomic absorption to analyse samples with high levels of dissolved and suspended solids (Perkin-Elmer Corp. 761 Main Ave. Norwalk CT 06859-0219 USA). 95/C764. de la Guardia M. Salvador A. Direct flow injection determination of metals in liposoluble matrices by atomic spectrometry (Univ. Valencia Dept. Anal. Chem. 50 Dr. Moliner St. 46100 Burjassot Valencia Spain). 95/C765. Ebdon L. Fisher A. Multi-element analysis using flow injection (Plymouth Anal. Chem. Res. Unit Univ. Plymouth Drake Circus Plymouth UK PL4 8AA). 95/C766. Burguera M. Burguera J. L. On-line microwave sample dissolution in FIA-AAS systems (IVAIQUIM (Andean Inst. Chem. Res.) Fac. Sci. Univ. Los Andes P.O. Box 542 Merida 5101-A Venezuela).95/C767. Pacey G. E. Sasaki K. Ozone as a possible alternative to conventional digestions for on-line flow injection- cold vapour AAS (Dept. Chem. Miami Univ. Oxford OH 45056 USA). 95/C768. Denoyer E. R. Debrah E. On-line column preconcen- tration of trace elements in seawater by FI-ICP-MS (Perkin-Elmer Corp. 761 Main Avenue Norwalk CT 95/C769. Sperling M. He Y.-z. Welz B. Capabilities and limitations of pressurised flow-through reactions for on-line sample pre-treatment for atomic absorption spectrometry (Dept. Appl. Res. Bodenseewerk Perkin- Elmer GmbH D-88647 Uberlingen Germany). 95/C770. Weiss A. D. Gintautas P. A. Piwoni M. D. Use of stable isotopes to evaluate selective extraction tech- niques for solid-phase metal speciation in contaminated soils (Hazardous Waste Res.and Information Center Champaign IL USA). 95/C771. McLeod C. W. Watson P. Mena M. Zhang Y. Woods G. Field sampling and flow injection strategies in atomic spectrometry (Environ. Res. Centre Div. Chem. Sheffield Hallam Univ. Sheffield UK S1 1WB). 95/C772. Ren J. M. Salin E. D. New approach to solid sample introduction for ICP-AES (Dept. Chem. McGill Univ. 801 Sherbrooke St. W. Montreal P.Q. Canada H3A 2K6). 95/C773. Sesi N. N. Shanks K. E. Hieftje G. M. ICP-AES matrix effects a progress report (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). 95/C774. Dziewatkoski M. P. Thaxton K. Bryden T. Olesik J. W. Effect of sample aerosol properties on analyte signals in the inductively coupled plasma (Lab. Plasma Spectrochem.Laser Spectrosc. and Mass Spectrom. Ohio State Univ. Dept. Geol. Sci. 1090 Carmack Road Columbus OH 43210 USA). 95/C775. Karanassios V. Drouin P. Spiers G. In torch vaporization (ITV) sample introduction system for ICP spectrometry (Univ. Waterloo Dept. Chem. Waterloo Ontario Canada N2L 3G1). 95/C776. Kacsir J. M. Meinhard B. A Nebulizer design effects of pressure and flow on ICP-AES (J E Meinhard Associates Inc. 1600-5 East Warner Ave. Santa Ana CA 92705 USA). 95/C777. Wiederin D. Sutton J. Ultra-clean micro autosampler and microconcentric nebulizer system for the introduc- tion of low volume samples for ICP-MS (CETAC Technol. 5600 S. 42nd Street Omaha NE 68107 USA). 95/C778. Wiederin D. R. Characterization of a high efficiency micro-concentric nebulizer for ICP spectroscopy (CETAC Technol.5600 S. 42nd Street Omaha NE 68107 USA). 95/C779. Wiederin D. R. Geil S. L. Barrett G. Improved ultrasonic nebulizer performance for ICP spectrometry (CETAC Technol. 5600 S. 42nd Street Omaha NE 68107 USA). 95/C780. McGowan G. J. Olesik J. W. Investigation of vaporization ionization and diffusion in inductively coupled plasmas using an on-demand monodisperse droplet generator (Lab. Plasma Spectrochem. Laser Spectrosc. and Mass Spectrom. Ohio State Univ. Dept. Geol. Sci. Scott Hall 1090 Carmack Rd. Columbus OH 43220 USA). 95/C781. Fonseca R. W. Miller-Ihli N. J. Wallace G. F. Ultrasonic slurry electrothermal vaporization solid sampling for ICP-AES and ICP-MS (US Dept. Agric. Beltsville Human Nutr. Res. Center Food Composition Lab.Beltsville MD 20705 USA). 06859-0215 USA). 122 R Journal of Analytical Atomic Spectrometry April 1995 Vol. 1095lC782. 95/C783. 95/C784. 9 5/C78 5. 95/C786. 95jC787. 95/C788. 95lC789. 95/c790. 95/c791. 95/c792. 951c793. 95/c794. 95/c795. 95/C796. 95/c797. Shen D. Y. Rayson G. D. Sangermano L. Rozenstraten A. Investigation of mercury analysis in wastewater by an inductively coupled argon plasma mass spectrometer (Environ. Sci. Lab. County Sanitation Districts of Orange County P.O. Box 8127 10844 Ellis Avenue Fountain Valley CA 92728-8127 USA). Koropchak J. A. Conver T. S. Allen L. B. Szostek B. Comparison of desolvated aerosols from ultrasonic and thermospray sample introduction systems for ICP spectrometry (Dept. Chem. SIUC Carbondale IL 62901 USA). Policke T.A. Bryant M. F. Analysis by ICP-MS of caesium in benzene recovered from the processing of simulated nuclear waste ( Westinghouse Savannah River Co. Savannah River Technol. Center Aiken SC 29808 USA). Zhou F.-m. Van Berkel G. J. Duckworth D. C. Morton S. J. Stripping analysis combined on-line with inductively coupled plasma mass spectrometry for enhanced trace metal analysis (Chem. and Anal. Sci. Div. Oak Ridge Natl. Lab. P.O. Box 2008/Bldg. 5510 Oak Ridge TN 37831-6365 USA). Plantz M. R. Wiederin D. Analysis of semiconductor- grade reagents by inductively coupled plasma mass spectrometry utilizing a direct injection nebulizer (Varian Associates 201 Hansen Court Suite 108 Wood Dale IL 60191 USA). Watling R. J. Herbert H. K. Bruce K. Use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in the interpretation of scene of crime evidence (Chem.Centre (WA) 125 Hay Street East Perty Western Australia 6004 Australia). Potter D. Sakata K. New insights into the origin of polyatomic interferences in ICP-MS ( Hewlett-Packard Company 2850 Centerville Rd. Wilmington DE 19808 USA). Hutton R. C. Tye C. T. Koller D. McLeod C. Progress on ultratrace determinations of actenides with an enhanced sensitivity ICP-MS instrument (F.I. Elemental Analysis Ion Path Road Three Winsford Cheshire UK CW7 3BX). Liang L. He L. Lubman D. Continuous-flow matrix- assisted laser desorption ionization in an ion trap storage-reflectron time-of-flight mass spectrometer (Dept. Chem. Univ. Michigan Ann Arbor MI 48109 USA). de Loos-Vollebregt M.T. C. van Veen E. H. Novel approach to the interpretation of data in ICP-MS (Delft Dept. Chem. Univ. Technol. Lab. Mater. Sci. Rotterdamseweg 137,2628 AL Delft The Netherlands). Wilkins C. L. Pastor S. New approaches to high- performance MALDI by FTMS (Dept. Chem. Univ. California Riverside CA 92521 USA). Cornett D. S. Lee T. D. Mahoney J. F. Massive cluster impact ionization of biomolecules (Beckman Res. Inst. of the City of Hope Duarte CA 91910 USA). Glish G. L. Ranasinghe Y. A. Thornquest A. D. Jr. Shinn D. W. Matrix assisted laser desorption-ioniz- ation combined with analysers other than time-of-flight (Dept. Chem. Univ. North Carolina Chapel Hill NC McIver R. T. Jr. Li Y.-z. High-resolution MALDI of biopolymers (Dept. Chem. Univ. California Irvine CA 92717 USA).Chalk S. J. Tyson J. F. Flow injection determination of chloride with reagent introduction without dilution (Dept. Chem. Univ. Massachusetts Box 34510 Amherst MA 01003-4510 USA). Mbakaya C. F. L. Evaluation of Amberlite IRC-718 for chelation of lead and copper from fresh and seawater 27599-3290 USA). 95,42798. 95lC799. 9 5/C 8 00. 95/C801. 95/C802. 9 5/C803. 95/C804. 95/cso5. 95/C806. 95/C807. 95lC808. 9 5 /C 809. 95/C810. 95/C8 1 1. 95/C812. 95/C813. samples prior to detection by FIA-FAAS (Kenya Med. Res. Inst. Med. Res. Centre P.O. Box 20752 Nairobi Kenya). Willie S. Sturgeon R. Flow injection hydride gener- ation with in-situ concentration in a graphite furnace (Inst. Environ. Res. and Technol. Natl. Res. Council Canada Ottawa Canada K1A OR9).Hollenbach M. Grohs J. Mamich S. Kroft M. Flow injection sample pre-treatment for the determination of radionuclides in soils by ICP-MS (US Dept Energy Grand Junction Projects Office P.O. Box 14000 Grand Junction CO 81502 USA). Burguera J. L. Burguera M. Time-based devices for sample introduction in flow injection atomic absorption spectrometry (IVAIQUIM (Andean Institute for Chemical Research) Faculty of Sciences University of Los Andes P.O. Box 542 Merida 5101-A Venezuela). Brindle I. D. Zheng X.-g. Cirello-Egamino J. Automated determination of arsenic in waters by flow injection atomic spectrometry (Chem. Dept. Brock Univ. St. Catharies Ontario Canada L2S 3A1). Wright L. J. Bye C. A. Hieftje G. M. Multi-species and multi-elemental excitation temperature measure- ments in an ICP using an kchelle-CID spectrometer (Indiana Univ. Dept.Chem. Bloomington IN 47405 USA). Tyson J. F. Recent developments in flow injection atomic absorption spectrometry (Chem. Dept. Univ. Massachusetts Box 34510 Amherst MA 01003-4510 USA). Pavski V. Sturgeon R. E. Chakrabarti C. L. Imaging of an ICC FAPES source at controlled pressure (Centre Anal. and Environ. Chem. Ottawa-Carleton Chem. Inst. Dept. Chem. Carleton Univ. Ottawa Ontario Canada K1S 5B6). Lancaster E. D. Ducatte G. R. Long G. L. Helium microwave induced plasma as an element specific detector for supercritical fluid extraction (Dept. Chem. Virginia Polytech. Inst. and State Univ. Blacksburg Virginia 24061-0212 USA). Falk H. Application of the short UV-range to ICP atomic emission (Spectro Analytical Instruments Boschstr.10 D-47533 Kleve Germany). Goldberg J. M. Minnick J. W. McKinstry J. Sampling strategies for the direct analysis of solids using a plasma gun-ICP tandem emission source (Dept. Chem. Univ. Vermont Burlington VT Caruso J. A Castillano M. T. Giglio J. Low pressure plasmas and their applicability for plasma mass spec- trometry (Dept. Chem. Univ. Cincinnati Cincinnati OH 45221 USA). Majidi V. Pogue R. Time-of-flight elemental mass spectrometry (Dept. Chem. Univ. Kentucky Lexington KY 40506 USA). Li G.-q. Mahoney P. P. Myers D. P. Heintz M. J. Hieftje G. M. Alternative plasma sources for atomic time-of-flight mass spectrometry (Dept. Chem. Indiana Univ. Bloomington IN 47405 USA). Mahoney P. P. Myers D. P. Li G. Heintz M.J. Hieftje G. M. Precision and interferences in atomic time-of-flight mass spectrometry (Chem. Dept. Indiana Univ. Bloomington IN 47405 USA). Zhang Z.-y. Karanassios V. Evaluation of the Kalman filter as a method of spectral interference correction in ICP-AES (Univ. Waterloo Dept. Chem. Waterloo Ontario Canada N2L 3G1). Burns D. A. Peristaltic pump noise a nemesis conquered (Los Alamos Natl. Lab. CST-1 MS G740 Los Alamos NM 87545 USA). 05405-0125 USA). Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 123 R95/C814. 95/C815. 95/C816. 95/C8 17. 95/C8 18. 95/C819. 95/C820. 95/C821. 95/C822. 9 5/C823. Zhang Z.-y. Karanassios V. Evaluation of partial least squares (PLS) as a method of spectral interference correction in ICP-AES (Univ. Waterloo Dept. Chem.Waterloo Ontario Canada N2L 3G1). Hutton J. C. Styris D. L. Gordon R. L. Conradson S. D. Lamoureux M. M. Hess N. J. Blanchard D. L. Speciation of Hanford nuclear wastes (Pacific Northwest Lab. P.O. Box 999 Richland WA 99352 USA). Mahan C. Gerth D. Direct solids analysis using a DC ARC CID spectrograph (Los Alamos Natl. Lab. CST-9 Los Alamos NM 87545 USA). Farmer 0. T. 111 Smith M. R. Barinaga C. J. Koppenaal D. W. Chromatographic separation of isobaric and polyatomic interferences in radionuclear ICP-MS applications (Pacific Northwest Lab. P.O. Box 999 MS P7-07 Richland WA 99352 USA). Eberlein S. J. Analytical challenges strategies and technology needs for the Hanford waste tank program (Westinghouse Hanford Company). Erickson M. D. Aldstadt J. H. Alvarado J.A. Crain J. S. Smith L. L. Orlandini K. A. Determination of radioisotopes in environmental samples $$ and sense (Argonne Natl. Lab. 9700 South Cass Avenue Argonne Murray K. K. Beeson M. D. Wei X. Russell D. H. Laser spray ionization for analytical mass spectrometry (Dept. Chem. Emory Univ. Atlanta GA 30322 USA). Carter M. Overview of the Department of Energy’s sampling and analysis activities of the Analytical Services Division (US Dept. Energy Anal. Services Div. EM-26 Quince Orchard Building Washington Amster I. J. Grigorean G. Wronka J. Laukien F. Development of a continuous-flow MALDI source for capillary electrophoresis or nanobore liquid chromatog- raphy mass spectrometry (Dept. Chem. Univ. Georgia Athens GA 30602 USA). Bonner Denton M. Recent advances in charge transfer device detectors (Dept.Chem. Univ. Arizona Tucson AZ 85721 USA). IL 60439-4831 USA). DC 20585-0002 USA). 95/C830. 95/C83 1. 95JC832. 9 5/C8 33. 95/C834. 95/C835. 95/C836. 95/C837. 95/C838. 95/C839. Yu L-j. Koirtyohann S. R. Turk G. C. Mass spectrometric detection of laser-enhanced ionization in an air-hydrogen flame (Dept. Chem. Univ. Missouri Columbia MO 6521 1 USA). RUSSO R. E. Fernandez A. J. Mao X. L. Shannon M. A. Laser ablation fundamental principles for analytical applications (Lawrence Berkeley Lab. Mail Stop 90-2024 Berkeley CA 94720 USA). Yuzefovsky A. I. Lonardo R. F. Michel R. G. Optical arrangement for detection of fluorescence in laser- excited atomic fluorescence spectrometry (Dept. Chem. Univ. Connecticut Storrs CT 06269 USA). Lonardo R.F. Yuzefovsky A. I. Michel R. G. Direct determination of phosphorus in polymers by laser- excited atomic fluorescence spectrometry in an electro- thermal atomizer (Dept. Chem. Univ. Connecticut Storrs CT 06269 USA). Liu H.-y. Montaser A. Phase-Doppler diagnostic studies of primary and tertiary aerosols produced by a new high-efficiency nebulizer (Dept. Chem. George Washington Univ. Washington DC 20052 USA). Rattray R. Alary J.-F. Salin E. D. High efficiency sample introduction for ICP atomic emission and mass spectrometry (Dept. Chem. McGill Univ. 801 Sherbrooke St. W. Montreal P.Q. Canada H3A 2K6). Liu X.-r. Horlick G. In-situ laser ablation sampling for inductively coupled plasma atomic emission spec- trometry (Dept. Chem. Univ. Alberta Edmonton Alberta Canada T6G 2G2).Karanassios V. Wood T. Direct sample insertion devices for ICP atomic emission and mass spectrometry (Univ. Waterloo Dept. Chem. Waterloo Ontario Canada N2L 3G1). Koropchak J. A. Conver T. S. Development of ultra- high performance sample introduction systems for ICP- AES based on thermospray processes (Dept. Chem. SIUC Carbondale IL 62901 USA). De Silva N. Guevremont R. Styris D. L. Lamoureux M. M. Hutton J. C. Koppenaal D. W. Direct powder introduction for plasma emission and mass spec- trometry (Geol. Survey Canada 601 Booth St. Ottawa Canada K1A OE8). 95/C824. Caprioli R. M. Electrospray and MALDI new tools for the study of dynamic biological systems (Dept. Biochem. and Mol. Biol. and Anal. Chem. Center Univ. Texas Med. Sch.. P.O. Box 20708.Houston. 95/c840. Jong9 R. French J. Etkin MDM1 a new frontier in sample introduction (Univ. Toronto Inst. Aerospace Studies 4925 Dufferin St. Downsview Ontario Canada M3H 5T6). TX 77225 USA). 95/CS41. Olesik .J. W. McGowan G. J. Dziewatkoski M. P.. 95/C825. Lipert R. J. Weeks S. J. Edelson M. C. Carney Monodisperse dried micro-particulate injector (MDMI) K. P. Mixed analyte in soils analysis using FAPES and sample introduction for inductively coupled plasma diode laser spectrometry (Ames Lab. Ames .IA 5001 1 spectrometry (Lab. Plasma Spectrochem. Laser Spectrosc. and Mass Spectrom. Ohio State Univ. Dept. Geol. Sci. 1090 Carmack Rd. Columbus OH 43210 USA). 95/C826. Koskelo A. Gamble T. K. Kos T. J. Cremers D. A. USA). RCRA in by break- 95/C842. Ebdon L. ICP-MS in the real environment (Plymouth Anal.Chem. Res. Unit Univ. Plymouth Drake Circus down spectroscopy (MS-J567 Los Alamos Natl. Lab. Plymouth UK PL4 8AA). Los Alamos NM 87545 USA). nebulization devices for LC-ICP-AES and LC-ICP-MS fill gas pressure and composition on theta-pinch interfacing (Sch. Chem. and Biochem. Georgia Inst. re-excitation of vapour sampled by a laser-induced Technol. Atlanta GA 30332-0400 USA). plasma (Dept. Chem. Univ. Vermont Burlington VT 95/C827- Goldberg J. M.9 Gluodenis Re O’Brien E.7 Effects of 95/C843. Browner R. F. Wang L.-~. H ~ s. ~ i ~ ~ ~ - 05405-0125 USA). 9 5/C828. Fernandez A. J. Mao X. L. Shannon M. A. RUSSO R. E. Correlation of laser-ablation plasma emission with ICP-AES signal intensity (Lawrence Berkeley Lab. Mail Stop 90-2024 Berkeley CA 94720 95/C844.Hinds M. W. Kogan V. Application of GFAAS and ICP-MS in determining trace elements in precious metal samples (Royal Canadian Mint 320 Sussex Dr. Ottawa Ontario Canada K1A OG8). USA. 95/C845. Gilchrist G. Rettbere T. Chloride effects in ETV- 95/C829. Eppler A. S. Cremers D. A. Hickmott D. D. Koskelo A. C. Matrix effects in the detection of Pb and Ba in ICP-MS (Fisons Instruments 55 Cherry Hill Dr. Beverly MA 01915 USA). soils using a laser plasma (Chem. Sci. Tech. Div. MS E525 Los Alamos Natl. Lab. Los Alamos NM 87545 USA). GmbH D-88647 Uberlingen Germany). 95/C846. Welz B. Sperling M. GFAAS-is it still worth the trouble? (Dept. Appl. Res. Bodenseewerk Perkin-Elmer 124 R Journal of Analytical Atomic Spectrometry April 1995 Vol. 1095/C847. Crecelius E. A. Tokos J. J.Direct analysis of metals in seawater by ICP-MS strengths and weaknesses of the multielement technique (Battelle Marine Sci. Council of Canada Ottawa Canada K1A OR6). S. N. ICP-MS and GFAAS-complementary tech- niques (Inst. Environ. Res. and Technol. Natl. Res. Lab. 1529 W. Sequim Bay Rd. Sequim WA98382 USA). 95/C849. Caruso J. A. ICP-MS for speciation studies strengths and weaknesses. (DeDt. Chem.. Univ. Cincinnati. 95/C848. McLaren J. W. Lam J. W. H. Sturgeon R. E. Willie Cincinnati OH 45221 bSA). Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 125R

ISSN:0267-9477    

DOI:10.1039/JA995100113R

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

Glossary of Abbreviations Whenever suitable elements may be referred to by their chemical symbols and compounds by their formulae. The following abbreviations are used extensively in the Atomic Spectrometry Updates. ac AA AAS AE AES A F AFS AOAC APDC ASV BCR CCP CMP CRM cv cw dc DCP DDC DMF DNA ECD EDL EDTA EDXRF EIE EPMA ETA ETAAS ETV EXAFS FAAS FAB FAES FAFS FANES FAPES FI FPD FT FTMS GC GD GDL GDMS Ge(Li) HCL hf HG HPGe HPLC IAEA IBMK ICP ICP-MS alternating current atomic absorption atomic absorption spectrometry atomic emission atomic emission spectrometry atomic fluorescence atomic fluorescence spectrometry Association of Official Analytical Chemists ammonium pyrrolidinedithiocarbamate anodic-stripping voltammetry Community Bureau of Reference capacitively coupled plasma capacitively coupled microwave plasma certified reference material cold vapour continuous wave direct current d.c.plasma dieth yldithiocarbamate N N-dimethylformamide deoxyribonucleic acid electron capture detection electrodeless discharge lamp ethylenediaminetetraacetic acid energy dispersive X-ray fluorescence easily ionizable element electron probe microanalysis electrothermal atomization electrothermal atomic absorption spectrometry electrothermal vaporization extended X-ray absorption fine structure flame AAS fast atom bombardment flame AES flame AFS furnace atomic non-thermal excitation spectrometry furnace atomization plasma excitation spectrometry flow injection flame photometric detector Fourier transform Fourier transform mass spectrometry gas chromatography glow discharge glow discharge lamp glow discharge mass spectrometry lithium-drifted germanium hollow cathode lamp high frequency hydride generation high-purity germanium high-performance liquid chromatography International Atomic Energy Agency isobutyl methyl ketone (4-methylpentan-2-one) inductively coupled plasma inductively coupled plasma mass spectrometry (ammonium pyrrolidin- 1-yl dithioformate) spectroscopy ID IR IUPAC LA LC LEAFS LEI LMMS LOD LTE MECA MIP MS NAA NaDDC NIES NIST NTA OES PIGE PIXE PMT PPb PPm PTFE QC rf REE(s) RIMS RM RSD SEC SEM SFC Si ( Li) SIMAAC SIMS SR SRM SSMS STPF TCA TIMS TLC TMAH TOP0 TXRF uhf uv VDU vuv WDXRF XRF S/B S/N isotope dilution infrared International Union of Pure and Applied Chemistry laser ablation liquid chromatography laser-excited atomic fluorescence spectrometry laser-enhanced ionization laser-microprobe mass spectrometry limit of detection local thermal equilibrium molecular emission cavity analysis microwave-induced plasma mass spectrometry neutron activation analysis sodium diethyldithiocarbamate National Institute for Environmental Studies National Institute of Standards and Technology nitrilo triacetic acid optical emission spectrometry particle-induced gamma-ray emission particle-induced X-ray emission photomultiplier tube parts per billion parts per million polytetrafluoroethylene quality control radio frequency rare earth element@) resonance ionization mass spectrometry reference material relative standard deviation signal to background ratio size-exclusion chromatography scanning electron microscopy supercritical fluid chromatography lithium-drifted silicon simultaneous multi-element analysis with a continuum source secondary ion mass spectrometry signal to noise ratio synchrotron radiation Standard Reference Material spark source mass spectrometry stabilized temperature platform furnace trichloroacetic acid thermal ionization mass spectrometry thin-layer chromatography tetramethylammonium hydroxide trioctylphosphine oxide total reflection X-ray fluorescence ultra-high frequency ultraviolet visual display unit vacuum ultraviolet wavelength dispersive X-ray fluorescence X-ray fluorescence 1 26 R Journal of Analytical Atomic Spectrometry April 1995 VoE.10

ISSN:0267-9477    

DOI:10.1039/JA995100126R

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

Laser Ablation Sampling with Inductively Coupled Plasma Atomic Emission Spectrometry for the Analysis of Prototypical Glasses R. E. RUSSO AND X . L. M A 0 Lawrence Berkeley Laboratory Berkeley C A 94720 USA W. T. CHAN Department of Chemistry University of Hong Kong Hong Kong M. F. BRYANT Savannah River Technical Center Westinghouse Savannah River Co. Aiken SC 29808 USA W. F . KINARD Department of Chemistry College of Charleston Charleston SC 29424 USA Laser ablation sampling is presented as an alternative to dissolution procedures for elemental analyses of prototypical glasses using inductively coupled plasma atomic emission spectrometry. These glass samples were prototypes of vitrified waste products from the Savannah River Technology Center. The sanqles were not translated or rotated during laser sampling but were repetitively sampled at a single spot using a KrF excimer laser with a 10 Hz repetition rate.The time- dependent mass ablation rate was measured and is discussed. Silicon the major element in the matrix was used as an internal standard and excellent precision (s = 1-3%) was obtained. Quantitative analysis was demonstrated using known prototypical glass compositions. Preferential vaporization was investigated by comparing measured elemental ratios using a nanosecond excimer laser (1 = 248 nm) and a picosecond Nd YAG laser (fourth harmonic 1 = 266 nm). Keywords Laser ablation; inductively coupled plasma atomic emission spectrometry; preferential vaporization; glasses; direct solid sampling Laser ablation with subsequent sample introduction into an analytical source provides several attractive benefits for direct solid sample chemical analysis.'-6 Primarily laser ablation sampling can be applied to any solid material without sample preparation.Sample preparation involving acid and microwave digestion is time consuming and is often a source of contami- nation and analyte loss. Also laser sampling consumes only a small amount of the sample typically in the range of ng to pg per pulse. Therefore personnel exposure sample handling and instrument contamination are minimized which are especially important for toxic or radioactive samples. Further the sam- pling area is small in the range of pm for a focused laser beam. With multiple-spot sampling over the target surface the elemental spatial homogeneity can be evaluated.Depth profi- ling is also possible with repetitive pulsing at a single location on the surface. Laser ablation is a process that involves coupling of the photon energy of a laser beam into the surface of a solid resulting in evaporation ejection of atomic and ionic species ejection of fragments (particles) from the surface due to shock waves and a hybrid of these proce~ses.~-'~ The thermal evapor- ation component may be deleterious for analytical purposes Journal Joyrnal of Analytical Atomic Spectrometry because elements of high vapour pressure can be enriched in the vapour phase relative to the original solid sample (preferen- B Y using nanosecond and shorter UV laser pulses rapid heating and explosive ejection can minimize preferential vaporization and provide stoichiometric sampling of the However the laser-material interaction involves complex non-linear dynamic processes.The amount and composition of the sampled vapour will depend on the properties of the sample and the laser beam parameters."-'' This work involves UV laser ablation sampling with induc- tively coupled plasma atomic emission spectrometry (ICP- AES) for elemental analysis of prototypical glass samples from the Savannah River Site Vitrification Facility. These glass samples are prototypes for vitrified radioactive waste products. The influence of laser beam parameters (pulse width and power density) on the laser-glass interaction was studied by monitor- ing the temporal ICP emission intensity as the laser beam repetitively ablated the solid glass samples.Power density studies were conducted by varying the laser beam spot size on the glass surface with fixed laser energy and by using lasers with nanosecond and picosecond pulse durations. The amount of material removed from the solid and introduced into the ICP (mass ablation rate) preferential vaporization of volatile components and elemental quantification using Si as an internal standard were addressed. These studies emphasize the understanding of laser sampling of prototypical glasses and are applicable to analysis using either ICP-AES or ICP mass spectrometry (MS). The research demonstrates that precise quantitative elemental analysis of prototypical glass samples is viable by laser ablation sampling. tial vaporization) rendering the analysis EXPERIMENTAL A diagram of the experimental system is shown in Fig.1. The primary components are an excimer or a Nd YAG laser an ICP and spectrometer with a photodiode-array detector and a microcomputer with associated data acquisition electronics. The KrF excimer laser has a pulse width of approximately 30 ns and A = 248 nm. An iris is placed between the laser and the focusing lens to limit the laser beam diameter to 6 mm so that the spatially more homogeneous portion of the excimer beam is used for these experiments. The energy of the laser at the sample surface is 30 mJ. The relative standard deviation of Analytical Atomic Spectrometry April 1995 Vol. 10 295Microcomputer (.I I I Laser sampling chamber t Iris Carrier gas IN Fig.1 Diagram of the LA-ICP-AES experimental configuration. The chamber is mounted on an xyz translation stage for focus and lateral adjustments. A nanosecond KrF excimer laser (1 = 248 nm pulse energy = 30 mJ) and picosecond Nd YAG laser (1 = 266 nm pulse energy = 10 mJ) were used (s,) of the pulse energy was measured to be 4%. The Nd YAG laser has a pulse width of 35 ps and the energy of the fourth harmonic (A=266 nm) is approximately 10 mJ. This laser was also pulsed at 10 Hz with an s in pulse energy of approximately 8%. The laser beam is focused on to the glass samples with a plano-convex lens with a 20 cm focal length. The effective focal length is 18.3 cm owing to a higher refractive index of the lens (fused silica) at the UV wavelengths. The samples are always placed before the effective focus of the lens.Depending on the position of the lens and the energy of the laser pulse the typical power density at the target surface is in the range 108-109 W cmP2 for the excimer laser and approximately two orders of magnitude higher for the Nd:YAG laser. Power density is estimated from the energy of the laser beam pulse width and measured spot area. For the excimer laser (30 ns 30 mJ per pulse) the diameter of the spot on the glass surface varies from approximately 1100 pm ( lo8 W cmV2) to 200 pm (3 x lo9 W cme2). The spot diameter is approximately 400 pm (240 x lo9 W The ICP is a Plasma Them 2500D operating at a forward power of 1.25 kW. The flow rates of the outer intermediate and central Ar gas are 15 1 and 11 min-I respectively.The central gas flow rate is regulated with a needle valve and monitored with a mass flow meter to ensure reproducible flow. A photodiode-array (PDA) spectrometer is used to monitor multiple wavelengths from the ICP simultaneously. T!e spec- trometer focal length is 0.32 m and dispersion is 25 A mm-' with a 1200 groovesmm-' grating. The PDA detector has 1024 pixels each of which is 25 pm x 2.5 mm. The PDA length is about 2.6 cm. Therefore the wavelength coverage is 60 nm with the 1200 groovesmm-' grating. The PDA detector is electrically cooled to reduce dark-current background. The ICP discharge is imaged with a 20cm focal length bi-convex singlet lens on to the entrance slit of the spectrometer with a demagnification ratio of 0.75. Typical slit width and slit height for the 35 ps Nd:YAG laser.Table 1 Composition (YO) of major elements for the SRTC glass samples* are 50 and 5 mm respectively. The observation height in the ICP is 10-15 mm above the load coil. A diagram of the laser sampling chamber is shown in Fig. 2. The main body has 0.d. 3.18 cm and i.d. 2.54 cm. The internal length of the chamber is 3cm. The chamber window is detachable to facilitate easy replacement. The window can be damaged by a high laser fluence and/or deposits from ablated samples. The sample holder is water cooled to maintain a constant temperature at the sample during long repetitive sampling experiments. The chamber is sealed from the atmos- phere with O-rings at the window and the sample holder. Carrier gas flows from the window toward the sample to minimize the deposition of material on the window.Laser sampled material is delivered to the ICP via a Teflon tube (20 cm x 3 mm i.d.). The chamber is mounted on an xyz- translator to position the sample relative to the laser beam. A chard of glass is mounted in the laser-sampling chamber with double-stick tape. The sample is not translated or rotated during laser sampling. Instead it is repetitively ablated at several surface locations using the 10Hz pulse rate from the laser. The samples are as-received chards of Savannah River Technology Center (SRTC) prototypical glass. The glasses are formed by melting a mixture of oxide reagents; five components (Mn Fe Si A1 and Mg) are listed in Table 1 for several samples. Si02 is the dominant matrix species at approximately 50% and the other four oxide concentrations range from 1.4% to 12.8%.These species were chosen for this work based on their relatively high concentrations and strong elemental spec- tral emission in order to measure good signal-to-background (ICP) ratios using the ICP-PDA system. Each glass sample contains fifteen additional oxides that only vary slightly among the samples; the physical thermal and optical properties are similar. The centre wavelength of the spectrometer is set at Ar gas OUT I Sample Window chamber \ I I c:p \ - Base I Sample O-ring 1 1 t Ar gas IN Fig. 2 Detailed diagram of the LA sampling chamber. The chamber is machined out brass rod. The window is a 1 mm thick quartz plate Oxide Batch 1 Batch 2 Batch 3 Batch 4 Blend 1 Px HM MnO 2.1 1 1.73 1.87 3.11 2.05 2.07 2.15 12.8 11.1 11.7 11.7 10.9 13.3 7.78 SiO 50.2 52.1 52.6 50.1 51.9 46.5 55.8 A1203 4.88 4.63 3.44 3.43 4.16 2.99 7.15 MgO 1.42 1.42 1.42 1.43 1.41 1.41 1.49 Fe203 * Fifteen additional oxides comprise each batch to total 100%.Variation in oxide concentrations from batch to batch are small. Optical and thermal properties are similar. Sample names (Batch Blend Px HM) represent correspondence to expected conditions at SRTC. 296 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10288 nm to monitor the entire range of emission lines from the five selected elements simultaneously. A typical background- corrected spectrum is shown in Fig. 3. RESULTS AND DISCUSSION Mass Ablation Rate Time Response The amount and composition of material ablated from the prototypic glass will be dependent on the laser beam param- eters.By using the excimer laser with a power density of 1.2 GW cm-2 the elemental emission intensity shows that the mass ablation rate changes with time during repetitive pulsing. Fig. 4 shows the temporal emission responses measured for Mn and Si respectively in the ICP. Similar behaviour is observed for all the elements listed in Table 1. The five graphs in Fig. 4(a) and (b) represent the mass ablation time response during repetitive sampling at five separate locations on a chard from batch 1 using fixed laser and ICP conditions. The spots (craters) are spaced 5mm from each other. The changing intensity level during repetitive pulsing at each spot demon- strates that the mass ablation rate does vary during the experiment.The exact time response of mass ablation during repetitive sampling depends on a number of factors including the sample surface and bulk properties laser beam energy and lens focusing arrangement. The time behaviour is not due to a change in power density as the crater is developed; the confocal parameter of the focused beam is several orders of magnitude longer than the final crater depth (approximately 1000 pm after 900 pulses). However the changing aspect ratio of the crater can influence the laser beam energy coupling into the material. The time profile will not always look like the data shown in Fig. 4 depending primarily on the sample and laser beam. For some metal alloy samples we measured a constant-level steady-state intensity over several minutes.The fact that mass ablation rate changes with time may complicate analytical utility. As shown in Fig. 4 the initial laser-material interaction is always measured to be more imprecise than the resultant long-term mass ablation behav- iour. For the five spots the signal intensity for the first 100 pulses (the initial peak in the profiles) differs significantly (s up to 50%). The precision for the five spots after 60s of pulsing improves to s = 5-8%. Although the mass ablation rate changes these data are very useful because the emission temporal profile for Mn exhibits the same mass ablation behaviour as that from,Si. The intensity ratio of Mn to Si is constant both in time and between spots except for the first 10 s which is omitted in Fig.4. Similar graphs are obtained .z 2000 c 1000 0 1 250 260 270 280 290 300 310 320 Wavelengthtnrn Fig. 3 Typical background-corrected spectrum for laser sampling of SRTC prototypical glass. The central wavelength of the PDA spec- trometer is set at 288 nm to cover the emission lines from Mn Mg Fe A1 and Si. Integration time 5 s for Mg Fe and A1 when compared with Si. Si was used as the internal standard because it is the dominant matrix element. The integrated intensity ratios for Mn Fe Mg and A1 to that of Si are listed in Table 2. The ratios represent the spectroscopic values not the mass abundance ratio in the solid sample. The spectroscopic intensity depends on the emission line strength and detector efficiency at the particular wavelength and also the amount of the material.The intensity ratios have excellent precision; for the five repetitions s varies from 0.3 to 1.7%. This excellent precision for successive spots demonstrates the improvement in the analytical figures of merit by repetitive pulsing and using an internal standard. The constant ratios demonstrate that there is no time- dependent fractionation of these elements over this time at this power density. Also these data demonstrate that the glasses are homogeneous in elemental composition throughout the crater depth. The crater diameters are about 200 pm and the depth is of the order of 1000 pm after 900 laser pulses. The sampling rate is therefore about 1 pm per laser shot. Depth profiling with this resolution or better is possible.Therefore the elemental ratio to Si provides an indication of homogeneity in the concentration distribution. Mass Ablation Versus Power Density The mass ablation rate at a particular time during repetitive pulsing is also dependent on the laser beam power density. By using the excimer laser with a fixed beam energy and translating the focusing lens to obtain spot sizes from approximately 1000 to 200 pm the power density is varied from 0.13 to 2.12 GW cmP2. The amount of glass sample ablated increases with increasing power density and reaches a maximum at about 0.3 GW cm-2. Fig. 5 shows the data for Fe and Si as a function of power density. Each data point in these graphs represents the averaged intensity from five spots measured after 60 s of pre-ablation.The reason for the plateau in intensity or mass ablation rate is believed to be plasma shielding. When a laser-induced plasma initiates at the target surface it can absorb or reflect a portion of the laser pulse energy thereby reducing the energy available for removing material mass.I7 Analysis of crater volumes for the same number of pulses verified that the mass ablation rate was reduced at the higher power densities; the plateau is not due to particle size or transport changes. Part of the plateau is due to the change in area of the spot which will be discussed in detail in a subsequent paper. Relative to Si the intensity ratio for Fe remains essentially constant over this power density range (Fig. 5). Similar behav- iour is measured for Mg Al and Mn.Tables 3 and 4 list normalized measured elemental intensities and their ratios to Si respectively. Although the amount of material ablated changes with power density the absolute intensity change is not significant if the power density changes only slightly especially in the plateau region (> 0.3 GW cm-2). Therefore the irregular surface of glass chards and thus the slight variation in lens-to-sample distance should not influence the mass ablation behaviour. Also by using Si as the internal standard the influence of power density on the mass ablation behaviour is minimized. The fact that the ratio remains constant for these elements also indicates that preferential vaporization is not significantly influenced by power density over this range. Previously we demonstrated that the Zn Cu ratio from brass samples varied over this same power density range.2 In that work we obtained the correct elemental ratio by using > 1 GW cm-2 as verified by dissolution and solution analysis of the brass sample.The effect of the glass-sample surface condition on laser ablation sampling was studied further. Several chards from Batch 1 were melted in a Pt crucible at 1075°C for about Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 297800 600 400 200 0 600- 400 200 I Mn 2500 2000 1500 1000 500 - - - - - - - I I I 1 1 1 1 I 3000 2500 2000 1500 1000 500 0 800 Mn 600 400 200 2500 2000 1500 1000 500 0 I Mn 3000 2500 2000 1500 1000 500 0 L 800 3000 0.3 OB4 * 0-4 7 0.2 1 I 0.2 C g 0.1 0 d ::I 0.1 ____I 1 0 40 80 120 160 Fig.4 Temporal mass ablation rate profiles for Mn and Si from ICP-ALES during repetitive sampling at five locations of SRTC prototypical glass using the nanosecond excimer laser repetition rate of the laser is 10 Hz and ratio of the Mn to Si data Table 2 Emission intensity ratios with respect to Si and the precision for the major elements from sample Batch 1 Wavelength/nm 257.61 273.96 279.55 285.21 309.27 Intensity ratio 0.3279 0.2676 2.4360 0.2223 0.4176 Standard deviation 0.0010 0.001 1 0.0181 0.0039 0.0065 ~ Relative standard deviation (Yo) 0.3 1 0.42 0.74 1.73 1.56 10min. The re-solidified sample adhered to the crucible and had to be broken out. Laser ablation of these samples provided the same intensity ratios and precision as measured for the original irregular shaped glass chard.Therefore sample prep- aration (smoothing the sample surface) is not necessary. The irregular shaped glass chard can be used as long as repetitive pulsing is used to ‘condition’ the sample surface. Laser ablation sampling can be significantly influenced by different gas atmospheres; only argon was used in these studies. Previously we measured higher ma% ablation rates in helium 298 Journal of Analytical Atomic Spectrometry April 1995 VuZ. 10Table 3 Normalized emission intensity versus lens-to-sample distance (laser power density) 0.9 .- ci! 0.7 2 d 0.5 2 .g 0.3 .- .I- c .I- t 0.1 Lens-to-sample distancelcm 14.3 14.8 15.8 16.8 17.3 17.6 ps Nd YAG laser ( C) - - ns excimer laser - ; Spot size/ cm 0.12 0.10 0.08 0.06 0.04 0.03 Power density/ GW cm-' 0.13 0.21 0.34 0.53 1.19 2.12 Normalized signal intensity Mn Fe MgO) Mg(11) Si A1 0.57 0.58 0.58 0.58 0.55 0.60 0.68 0.7 1 0.68 0.70 0.66 0.72 1.01 1.04 1.04 1.06 0.96 1.10 1.06 1.07 1.09 1.12 1.03 1.20 0.98 1 .oo 0.98 1 .oo 0.97 1.04 1 .oo 1 .oo 1 .oo 1 .oo 1 .oo 1 .oo Table 4 Normalized emission intensity ratios with respect to Si versus laser power density Power density/ ~ GWcm-2 Mn/Si 0.13 1.04 0.21 1.02 0.34 1.05 0.53 1.03 1.19 1.01 2.12 1.00 Normalized signal intensity ratio Fe/Si Mg(r)/Si Mg(rI)/Si 1.05 1.05 1.06 1.06 1.03 1.05 1.08 1.08 1.11 1.04 1.06 1.09 1.02 1.01 1.03 1 .oo 1 .oo 1 .oo Al/Si 1.09 1.07 1.14 1.16 1.06 1 .oo L 5000 ? 4000 > ._ +- C - 3000 2000 1000 0 Si .@ . 0 0 0 0 0.3 ' .r" 1 0.1 0 0.5 1.0 1.5 2.0 2.5 Power density/GW cm-2 Fig. 5 ICP-AES signal intensity versus laser power density for LA sampling of SRTC prototypical glass.Each data point represents the average of intensity for five spots obtained 60 s after pre-ablation at 10 Hz. Data are from nanosecond KrF excimer laser sampling for metal sampleslg and stoichiometric sampling of brass in oxygen. Also laser sampling generates a large amount of particles. Incomplete vaporization and atomization in the ICP and deposition on the sampling cone of an ICP-MS are potential problems.20 The amount of sample ablated and the size distribution of the particles should be addressed especially for ICP-MS. Picosecond Versus Nanosecond Laser Sampling A primary concern in this and other laser ablation sampling studies is demonstrated by the data in Fig.6. The data in Fig. 6(a) show the time-dependent mass ablation rates for Mg and Si using the nanosecond excimer laser at 1 GW cm-2 (similar to the data in Fig. 4). The time-dependent mass ablation rate using the picosecond Nd:YAG laser with a power density of 240 GW cm-2 for the same two elements is shown in Fig. 6(b). Similarly to the nanosecond sampling the initial interaction for picosecond laser sampling provides dras- tic variations in the intensity level versus the longer time response. A primary difference between the nanosecond and picosecond ablation can be seen by plotting the ratio of these data [Fig. 6(c)J. For the same prototypical glass sample the intensity ratio of Mg to Si is different from the two lasers. 10000 I 1 9000 8000 7000 6000 $ 3 0 0 0 p I L .e 2000 I I I I I J -Ef Si 8000 2000 ' I I I 1 I I 1 1 I 0 20 40 60 ao 100 Time/s Fig.6 Temporal mass ablation rate profiles of Mg and Si during repetitive laser sampling of SRTC prototypical glass using (a) nano- second pulsed excimer laser (A = 248 nm) and (b) picosecond pulsed Nd YAG laser (A = 266 nm).(c) Mg Si intensity ratio for the two lasers Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 299Table 5 Emission intensity of Mg Al Mn and Fe with respect to Si using the picosecond Nd YAG (3 = 266 nm) and nanosecond KrF excimer ( A = 248 nm) lasers after 60 s of pre-ablation Laser Nd YAG KrF excimer Power density/ GW cm-' MgO)/Si Mg(II)/Si Al/Si Mn/Si Fe/Si 240 1.2 2.56 2.18 0.66 0.40 0.41 0.24 0.52 0.3 1 0.38 0.24 Again the ratios are of spectroscopic intensities not the mass abundance of the solid sample.The glass samples were not dissolved and analysed using solution nebulization. Therefore we do not know which intensity ratio is correct. A complete mechanism to describe the different elemental ratios measured using nanosecond and picosecond pulses would require an understanding of energy coupling mechan- isms energy dissipation hydrodynamic expansion gas dynamic expansion particle size distribution gas entrainment plasma interaction with the laser beam and target surface and solid sample excitation characteristics in the ICP. Such extens- ive studies have been conducted for the past 45 years yet still cannot accurately describe the ablation mechanism. A compo- nent of the laser material interaction is believed to be thermal vaporization which may lead to preferential vaporization at some point during laser ablation sampling of glass.Assuming partial thermal behaviour we can qualitatively explain the picosecond uersus nanosecond data based on melting- and boiling-points of the oxides. The emission intensity ratios for Mg Al Mn and Fe obtained with nanosecond excimer and picosecond Nd YAG laser sampling (after 60 s) are listed in Table 5. Both Mg and A1 have a higher intensity ratio using the higher power-density picosecond Nd YAG laser whereas Mn and Fe have the same ratios for both lasers. The melting-points of the Mg and A1 oxides are significantly higher than that of Si while Mn and Fe oxides have lower melting points (Table 6 ) .A preferential vaporization mechanism may explain the differences in inten- sity ratio. For the nanosecond excimer laser the sample is heated to a temperature that is not high enough for complete removal of the more refractory oxides (Al Mg). The oxides with lower melting points (Mn Fe) than this induced surface temperature can vaporize preferentially and be enhanced in the vapour phase. As the picosecond Nd:YAG laser has a higher power density the sample temperature can rise faster and to a greater extent than that of the nanosecond excimer laser. Based on this argument the intensity ratios (to Si) for elements with higher melting-point oxides (Mg and Al) can be larger with the picosecond Nd YAG laser. The argument can be extended to the boiling-points of the individual oxides (Table 6 ) .An interesting observation is that SiO MgO and A1203 have well defined boiling points whereas Mn02 and Fe,O undergo several phase transitions and release 0 as temperature increases.18 Again only considering the thermal component of the interaction the heated volume is expected to be raised to a higher temperature during the picosecond than the nanosecond pulse (the energy is the same only the time is different). For the higher temperature the vapour pressure of the Al,O MgO and SiO will be increased whereas Table6 Thermal properties of the major oxides in the SRTC glass samples'8 Oxide Melting-point/"C Boiling point/"C * * - 1564 Fe203 1594 SiOZ 1723 2230 A1203 2072 2980 MgO 2852 3600 - Mn304 * Undergoes several phase transitions before reaching a stable boiling compound.the additional temperature could be dissipated in ancillary phase transitions for the MnO and Fe203. Of course preferential vaporization based on melting boiling and phase transitions is not the complete mechanism to explain these data; the n-ature of the laser material interaction is a complicated convolution of many mechani~ms.l~-'~ The actual vapour pressure-temperature behavior is complicated by the high pressure from the induced shock wave. Also preferential vaporization may be due in part to the laser-induced plasma initiated over the glass surface. Convective and/or radiative heat transfer from this plasma may influence the amount of mass ablated and its composition. The influence of plasma heating on preferential vaporization has not been investigated.Another parameter that may have influenced these data is laser beam ~oherence.'~*'~ The excimer laser with unstable resonator optics has entirely different spatial coherence to the solid-state picosecond Nd YAG laser. It is interesting that neither time response curve in Fig. 6(c) approaches the other even after creating a deep (several hundred micrometres) crater in the glass. It might be expected that forced congruency would act to regulate the ablated mass ratios if preferential vaporization was the dominant factor influencing these data. Although the mechanism to explain these data cannot be confirmed by these studies heuristically these data show that the composition of sample in the ICP is effected by the laser beam properties.Quantitative Analysis Although the above discussion points out complexities in laser ablation sampling most systems will not offer such variations in laser beam properties (picosecond versus nanosecond pulses). For a fixed set of conditions a suite of similar samples may exhibit similar ablation behaviour. Analytical accuracy could be verified by dissolving one of the samples and 'calibrating' the instrument response. For the seven SRTC prototypical glasses the oxide concentrations vary only slightly providing similar physical thermal and optical properties among these samples. A quantitative study does show that linear calibration graphs can be measured when Si is used as the internal standard (Fig. 7). The ordinate is the measured emission intensity ratios (to Si) and the abscissa is the prepared oxide concentration ratios. Again each glass chard was sampled at five different spots over its surface and the signal intensity was recorded after 60 s of pre-ablation; s is typically 1-3%.The correlation coefficients (r) for these data are 0.98-0.99 except for that of Mg which is 0.70. The lower correlation for the Mg data may be due in part to the small difference in concentration ratio among the different batches. Also as demonstrated earlier Mg ablation was influenced more than the other three elements by the pulse width of the laser. However these linear calibration graphs demonstrate that laser ablation sampling is a viable approach for direct chemical analysis of solid prototypical glasses. These studies only measured the major elements in the glass because of the low sensitivity of our photodiode-array detector.The applicability of these results to the other trace elements in the glass could be investigated using a more sensitive ICP detector system. A charged-coupled device (CCD) detector which is three orders of magnitude more sensitive than the 300 Journal of Analytical Atomic Spectrometry April 1995 Vol. 100.4 0.3 0.2 >. 0.03 0.04 0.05 0.06 0.07 4- .- 2.2 - 8 - 2.1 2.0 1.9 1.8 0.026 0.028 0.030 0.032 0.25 0.20 0.15 0.10 0.15 0.20 0.25 0.30 0.5 0.4 0.3 0.2 (d) AI:Si 0.050 0.075 0.100 0.125 0.150 Concentration ratio Fig. 7 Calibration graphs for measured elemental Si ratio versus the prepared (nominal) concentration. Nanosecond excimer LA sampling of SRTC prototypical glass with ICP-AES PDA detector will be used in future studies.Ideally an ICP-MS would provide the best sensitivity for performing these studies. CONCLUSION Laser ablation sampling for ICP-AES is a viable approach for directly measuring the elemental composition of SRTC proto- typical glasses without dissolution procedures. For these glasses pre-ablation for 60 s before data acquisition minimizes the effect of sample surface condition and geometry. By using silicon as the internal standard excellent precision and quanti- tative analysis with matrix-matched standards were demon- strated; the precision was better than 1% for several of the elements. Stoichiometric sampling is a vital issue for direct chemical analysis of solids and this work showed that the picosecond Nd YAG laser provided a different analysis from the prototypic glass samples compared with that of the nano- second excimer laser.However most systems would not offer such drastic differences in laser pulse width and dissolution of several samples could be performed to calibrate the particular instrument. The suite of SRTC prototypical glass samples seemed to ablate similarly as evidenced by the linear Cali- bration graphs obtained. The ratio of elements to the Si internal standard remained constant over a wide power density range using the nanosecond UV excimer laser pulses. Therefore changes in the power density during sampling will not effect the accuracy especially as a crater develops at the sampling location. Time response measurements showed that the ratio remained constant throughout a 1000 pm depth indicating the homogeneity of elements in these glass samples.The authors acknowledge Mark Shannon and Marvin Kilgo for technical assistance. This research was supported by the US Department of Energy Office of Basic Energy Sciences Division of Chemical Sciences under Contract No. DE-AC03-76SF00098 and by Savannah River Technology Center. REFERENCES 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 McLeod C. W. Routh M. W. and Tikkanen M. W. in Inductively Coupled Plasma in Analytical Atomic Spectrometry ed. Montaser A. and Golightly D. W. VCH New York 2nd edn. 1992 ch. 16. Chan W. T. and Russo R. E. Spectrochim. Acta Part B 1991 46 1471. Walder A. J. Abell I. D. and Platzner I. Spectrochim. Acta Part B 1993,48 397. Drake S. A. and Tyson J. F. J. Anal. At. Spectrom. 1993 8 145. Moenke-Blankenburg L. Schumann T. Ganther D. Kuss H. M. and Paul M. J. Anal. At. Spectrom. 1992 7 251. Durrant S. F. and Ward N. I. Fresenius’ J. Anal. Chem. 1993 345 512. Phipps C. R. and Dreyfus R. W. in Laser Ionization Mass Analysis ed. Vertes A. Gijbels R. and Adams F. Wiley New York 1993 ch. 4. Klocke H. Spectrochim. Acta Part B 1969 24 263. Dabby F. W. and Paek U.-C. IEEE J. Quantum Electron. 1972 8 106. Olander D. R. Yagnik S. K. and Tsai C. H. J. Appl. Phys. 1988,64 2680. Thompson M. Chenery S. Brett L. J. Anal. At. Spectrom. 1990 5 49. Chan W. T. Mao X. L. and Russo R. E. Appl. Spectrosc. 1992 46 1025. Chenery S. Hunt A. and Thompson M. J. Anal. At Spectrom. 1992 7 647. Baldwin J. M. Appl. Spectrosc. 1970 24 429. Ready J. F. Eflect of High-Power Laser Radiation Academic Press New York 1971. Hughes T. P. Plasmas and Laser Light Wiley New York 1975. Von Allmen M. Laser Beam Interactions with Materials - PhysicaE Principles and Applications Springer New York 1987. Handbook of Chemistry and Physics ed. Lide D. R. CRC Press Boca Raton FL 75th edn. 1994. Mao X. L. Chan W. T. Shannon M. A. and Russo R. E. J. Appl. Phys. 1993 74 4915. Crain J. S. Houk R. S. and Smith F. G. Spectrochim. Acta Part B 1988 43 1355. Paper 4/05 15 7B Received August 23 1994 Accepted November I 1994 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 301

ISSN:0267-9477    

DOI:10.1039/JA9951000295

出版商:RSC    

年代:1995

数据来源: RSC

摘要:

Determination of Trace Elements in Food Contact Polymers by Semi-quantitative Inductively Coupled Plasma Mass Spectrometry. Performance Evaluation Using Alternative Multi-element Techniques and In-house Polymer Reference Materials Journal of Analytical Atomic Spectrometry PETER J. FORDHAM AND JOHN W. GRAMSHAW Procter Department of Food Science University of Leeds Leeds LS2 9JT UK LAURENCE CASTLE AND HELEN M. CREWS Ministry of Agriculture Fisheries and Food CSLFood Science Laboratory Norwich Research Park Colney Norwich NR4 7UQ UK DIANA THOMPSON AND SUSAN J. PARRY Centre for Analytical Research in the Environment Imperial College of Science Technology and Medicine Silwood Park Buckhurst Road Ascot Berkshire SL5 7TE. UK ED McCURDY Fisons Instruments Elemental Analysis Ion Path Road Three Winsford Cheshire C W7 3BX UK The determination of trace elements in a wide range of polymers intended for food contact use was carried out by inductively coupled plasma mass spectrometry (ICP-MS).Microwave digestion in concentrated nitric and sulfuric acids enabled rapid wet oxidation of all the polymers to give samples suitable for introduction into the plasma. Semi- quantitative multi-element screening of the polymer digests could then be carried out using a single indium internal standard. Limits of detection for the polymers were generally in the order of 1 mg kg-l. Owing to the paucity of suitable standard reference polymer materials required for validation of the procedures used a series of in-house reference materials was prepared by incorporating a cocktail of metal stearates into a range of polymer materials uia the melt. Levels of elements in these reference materials were established by two reference methods direct neutron activation analysis (NAA) and a quantitative ICP-MS method.Results for the two reference methods were encouragingly close to nominal added values and replicate analyses indicated that homogeneity was good. Further analysis of the materials using laser ablation ICP-MS confirmed that the distribution of elements within the polymer matrix was satisfactory. In addition NAA was carried out on the great majority of the polymer samples as a further aid to validation of the semi-quantitative multi-element ICP-MS method. Keywords Inductively coupled plasma mass spectrometry; microwave digestion; multi-element reference materials; food contact polymers; neutron activation analysis; laser ablation Polymers may contain low levels of the chemicals used in their manufacture or else substances derived from them such as catalyst residues.For polymers intended for food contact use such as packaging these substances may migrate (transfer) from the polymer into food so that there is a need to identify possible food contaminants. The greater proportion of pro- posed limits for residual elements in food contact polymers are in the form of migration limits' but there is clearly a need to identify and determine the levels of trace elements present in the polymer in order to target substances for later migration work. A wide range of spectrometric techniques have been applied to the determination of trace elements in polymers,2 most of which require some sample preparation prior to analy~is.~ X-ray fluorescence spectrometry (XRF) is well-suited to the rapid elemental analysis of solid material^.^ It is widely used by the plastics industry in a quality control capacity and occasionally for on-line analy~is.~ Sample preparation is mini- mal and.sensitivity is typically in the pg kg-' region. For quantitative analysis reference materials are required unless complex fundamental parameter techniques are employed.6 Atomic absorption spectrometry (AAS) has been used exten- sively for the trace element analysis .of polyrners?l0 Its chief drawback is that instrumentation is generally only able to measure a single atomic species at a time so that each method described in the literature tends to concentrate on one particu- lar element or handful of similar elements.Thus there is a wide range of sample preparation methods which are often specific to the atomic species under scrutiny and unproven for multi-element work. An analytical technique which has made considerable gains in popularity for elemental analysis is inductively coupled plasma mass spectrometry (ICP-MS)." A liquid sample is frequently required for sample introduction which for poly- mers usually necessitates the use of laborious digestion pro- cedures. However the recent availability of equipment which enables wet oxidation of polymers by microwave digestion in sealed containers can lead to a significant reduction in the time required for sample preparation.The high sensitivity offered by ICP-MS (typically ppb) offsets the loss in sensitivity incurred by the sample dilution which usually accompanies digestion of the polymer matrix. Furthermore ICP-MS has the ability to generate multi-element data. For most instru- Journal of Analytical Atomic Spectrometry April 1995 V01.10 303ments a plot of mass uersus sensitivity yields a reasonably smooth response curve (once isotopic abundance and degree concern (Pb). Levels of the elements thus incorporated were verified by NAA and a quantitative ICP-MS method (standard of ionization have been taken into account) which can be stored and used to generate semi-quantitative multi-element data for samples of unknown elemental composition.A handful of elements (typically 4-10) spread across the mass range characterize the response curve and an internal- standard can be used to allow referral back to the stored curve and to correct for instrumental drift. The figures thus obtained are usually within a factor of three of known values.I2 Verification of performance may be carried out by running multi-element reference standards at periodic intervals. This technique appears to be potentially one of the more straight forward and affordable techniques for multi-element analysi~.'~-'~ Laser ablation (LA) is a technique of micro-sampling which has received much attention over the last few years as a useful means of introducing solid samples into the ICP-MS,16,17 and this facility has recently been applied to the determination of trace elements in polymers.18 Samples are volatilized by directing a laser beam at the polymer surface and the ablated material is transferred to the plasma thus removing the need for lengthy sample preparation procedures.Again semi- quantitative multi-element data are generated with an accu- racy that can be within a factor of two." As the polymer matrix consists largely of carbon with uniform distribution and as long as the carbon content is known 13C is an ideal internal standard." Neutron activation analysis (NAA) is a technique which is well-suited to analysing polymer materials20.21 that would otherwise be difficult to dissolve or where volatile elements may be lost in the sample processing required for other techniques.The determination of trace elements in polymers where carbon and hydrogen are the main constituents is straight forward as the matrix gives no background effects and it is therefore possible to analyse several grams of material generating quantitative multi-element data. It is a highly sensitive non-destructive technique and is frequently used to establish the elemental composition of reference materials. As part of a project directed at determining catalyst residues in polymers and their potential for migration into food trace elements were determined in polymer materials intended for food contact use by a multi-element semi-quantitative ICP-MS method following microwave digestion of the polymer matrix in concentrated nitric and sulfuric acids. Evaluating the performance of an analytical method for trace elements in polymers is best achieved by using matrix- matched reference materials.However since polymer standards for trace element analysis are not commercially available the more usual approach is to use polymer samples which have been analysed by another method18 or alternatively to prepare a number of synthetic polymer reference materials. Kolomitsev et a1.22 prepared multi-element thermoset polymer reference materials for NAA based on phenol fomaldehyde resins and the method has undergone modifications aimed at improved distribution of incorporated elements.23 However as far as the work reported here is concerned the application of interest is food contact plastics and it was therefore felt that closer matrix matching was desirable.In order to fully validate the semi-quantitative microwave digestion-ICP-MS method both courses were adopted. Neutron activation analysis was used as a reference method and a series of in-house reference materials was prepared by incorporating a cocktail of seven elements (Mg Al Cry Coy Zn Sb and Pb) in the form of metal stearates plus antimony trioxide into a range of thermoplastic food-contact-grade polymers. The elements were selected to cover a wide mass range and to be representative of those most frequently encoun- tered in polymers intended for food contact applications (Mg Al Cr Co Zn Sb) or representative of elements of toxic additions following microwave digestion of the polymer matrix). An indication of element distribution was obtained from analysis by LA-ICP-MS and the potential use of these reference materials for quantitative analysis by the laser technique was briefly explored. EXPERIMENTAL Preparation of Polymer Reference Materials Reagents Five types of polymer [low density poly(ethy1ene) (LDPE) high density poly(ethy1ene) (HDPE) poly (propylene) (PP) poly(ethy1ene terephthalate) (PET) and poly(styrene) (PS)] were supplied in bulk by large-scale manufacturers of polymers intended for food contact applications.Metal stearates (Al Cr Co Mg Pb and Zn) and antimony trioxide were obtained from Pfaltz and Bauer. Equipment Polymer compounding was carried out at RAPRA Technology (Shawbury Shrewsbury UK). An APV Baker MP 2030-25 XLT twin screw compounding extruder with a K-Tron feeder was used to enable the stearates and antimony trioxide to be incorporated into the polymer materials and an Accrapack strand cutter was used to pelletize the extruded polymer.Procedure Stearates and antimony trioxide were weighed out to give nominally 50 mg (as metal) of incorporated material per kg of polymer then pre-blended with each polymer material by tumble-mixing to achieve even distribution. The blend was then transferred to the hopper of the compounder's K-Tron feeder and the strands of molten polymer produced were passed through a water bath to solidify. The solidified polymer was then pelletized. Virgin polymer resins required as control sampIes were processed in the same way (without incorporated stearates). Microwave Digestion and Determination of Trace Elements by Reagents Forty-five polymers of food-contact-grade were supplied by large-scale manufacturers of polymer materials.Concentrated sulfuric and nitric acids (Aristar grade BDH) were used for polymer digestion and the indium standard used for semi- quantitative determinations was Spectrosol grade indium nitrate (1000 mg 1-I) in nitric acid (0.5 moll-') (BDH). ICP-MS Instrumentation An MDS-81D Microwave Digestion System (CEM Corporation) was used to carry out digestion of polymer materials. The digestion vessels were fabricated from Teflon perfluoroalkoxy (PFA); screw tops fitted with safety valves allowed pressure release at 7 x lo5 Pa and the instrument was programmable for time and microwave power. A VG Plasmaquad PQ1 instrument (with extended dyramic range) was used for all ICP-MS measurements.Conditions used are given in Table 1. Measurements were made in the scanning mode with post-run data manipulation being handled by the calculations software module and concentrations calcu- lated using semi-quantitative analysis algorithms contained therein. Semi-quantitative data were produced by the software 304 Journal of Analytical Atomic Spectrometry April 1995 Vo!. 10Table 1 ICP-MS operating parameters ICP radiofrequency forward Carrier gas flow/l min - ' Intermediate gas flow/l min-' Outer gas flow/l min-l Number of channels Number of scan sweeps Dwell time/ps Detector mode Sample uptake rate/ml min-' Nebulizer type Sample cone Skimmer Mass range power/W Isotopes selected for measurement 1350 0.8 0.5 13 2048 100 320 pulse 0.75 cross-flow (Sci-Tek Instruments) platinum (1 mm orifice) Nicone (0.75 mm orifice) 6-240 (skipped regions 12-23.5 27.5-41.5 and 79.5-80.5) 24Mg 27Al "Cr 55Mn "Co 68Zn 72Ge "Zr "'Sb and "*Pb based on an indium (l151n) internal standard and using the response curve generated from a multi-element reference solution containing 50 ppb each of Be Mg Co In and U.Procedure A two-step digestion procedure was employed to digest poly- mers. The first step accomplished the essential initial charring of the polymer matrix so that the more vigorous second step could achieve digestion. An accurately weighed sample (0.5 g) of polymer was placed into a digestion vessel. Concentrated sulfuric acid (8 ml) and nitric acid (3 ml) were added and the caps tightened to finger tight only.All vessels were then placed on the microwave oven turntable until the carousel held a total of twelve vessels and venting tubes were attached. The instrument was programmed for 15min at 75% power (100%=650 W) for the first stage of digestion. The sample was allowed to cool to room temperature before an additional 5 ml of concentrated nitric acid was added to each sample and the cap was replaced and tightened to 330 Nm. The vessel was returned to the turntable for the second digestion stage 30 min at 100% power with a full carousel and allowed to cool to room temperature before venting and transferring to an appro- priate container. For multi-element semi-quantitative analysis digests were diluted ten-fold in de-ionized distilled water and the indium internal standard was added to give a concentration in the final diluted sample of 100ppb prior to introduction into the plasma of the ICP-MS instrument.Reagent blanks were also taken through the entire procedure. For quantitative analysis by the method of standard additions digests were diluted ten-fold following three additions of aliquots of standard solutions to give fortification of the diluted sample corresponding to approximately %YO 100% and 150% of the concentration of the analyte as determined by the semi-quantitative method. Neutron Activation Analysis Instrumentation The neutron flux was obtained using a 100kW pool-type research reactor. This provided a flux in the range of 1 x 10l6 neutrons m-2 s-' Gamma ray detection was performed using a high purity germanium semiconductor detector (EG & G Ortec Gamma X; efficiency 20% at 1.33 MeV; FWHM 0.91 at 0.059 MeV and 1.87 at 1.33 MeV; peak Compton 60.4).Procedure An accurately weighed sample (5 g) of polymer was placed in low density poly(ethy1ene) capsules which were then placed in larger poly(ethy1ene) containers for irradiation. Two different sets of conditions were used for the analysis of polymers. The first method made use of the pneumatic facility for loading samples into the reactor core to give an irradiation time of 10 min. This was followed by a decay time of 5 min and then a count period of 10min. A second method was used for longer lived radioisotopes and this made use of the tubes around the outside of the reactor core. The irradiation period was for 7.5 h with a decay period of 16 h followed by a count period of 16.7 min.A second count of 50 min was then per- formed after a total decay time of 10 days. After counting the spectra obtained were processed using EG & G Omnigam computer software for peak evaluation. Quantification of the elements in the sample was achieved by using a database of single element standards since a standard containing fifty or more elements would produce too much activity to measure each individual element successfully. A limited standard was prepared by accurately doping four standard element solutions onto cellulose powder to reproduce the sample geometry. These standards were run with the samples to provide a check on the database and also for calibration purposes.Detection limits were based on the formula 5 x ,/(2 x background + 6.25) + 2.5 Laser Ablation Inductively Coupled Plasma Mass Spectrometry Instrumentation A VG Laserlab system was used to carry out all measurements (selected parameters are presented in Table 2). The YAG laser was operated at its fundamental frequency (1064nm) and ablated craters approximately 400 x 125 pm (diameter x depth). Elements were measured using either the analogue or pulse- counting detector mode. The appropriate detector mode was selected automatically for each isotope in each sample by the auto-scan software facility. Procedure Polymer reference materials were analysed for homogeneity. Pellets were simply placed on a holder into the laser cell. Several samples can be placed in the holder at the same time allowing for automated unattended analysis. RESULTS AND DISCUSSION Semi-quantitative ICP-MS One of the chief drawbacks of ICP-MS is the occurrence of spectral interferences such as oxide ions and polyatomics derived from the sample matrix.24 The use of nitric and sulfuric acids for this piece of work which were required to achieve complete digestion of all the polymers introduces interferences additional to those that may be attributed to residual carbon from the digested polymer matrix leading to signal enhance- ment for some isotopes.Blank reagent subtraction overcomes smaller interferences but for certain isotopes these interferences are too large and unless an alternative isotope can be used determination is not possible. Such interferences can be seen Table 2 Laserlab operating parameters Pre-ablation time/s 5 Ablation ratelHz 2 Laser mode Q-switched Focus Acquisition Focused at the sample interface 30 s scanning in dual mode Analysis area/pm diam.z400 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10 305in the spectrum of the reagent blank (Fig. 1) and are summar- ized in Table 3 (natural abundance ratios were used to substan- tiate the identity of the designated interferences). Most can be attributed to the mineral acids used for the digestion procedure and particularly to polyatomics derived from sulfuric acid. Reliable data for calcium iron and titanium could not be obtained owing to gross interferences coinciding with isotopes measured. The most significant interference originating from the carbon of the polymer is 40Ar12C which is a well- documented interference for 52Cr.Following comparison of the chromium data for the two analytical techniques the detection limit for this element (for the ICP-MS method) was elevated to 2 mg kg- and a further background subtraction was applied to correct for interference from Arc (calculated to be present at a level equivalent to 0.7k0.4 mg kg-' chro- mium). For future work monitoring of the 53Cr isotope should be considered. Possible interferences derived from residual carbon include 12C2 12C2H and 12Ci4N for 24Mg "Mg and 26Mg respectively; and 12C14NH for 27Al. However close inspection of isotope ratios indicated that these interferences were not a major problem. A total of 73 defined isotopes comprising 69 elements were 14000 12000 10000 8000 6000 .- 2 4000 A = 2000 )r G E.1000 .= 900 s 800 v) c 400 300 200 100 0 40 50 60 m/z 70 80 Fig. 1 Spectra of nitric acid-sulfuric acid reagent blank for polymer digestion procedure (a) major interferences displayed and (b) minor interferences displayed (intensity scale x 14) Table 3 Principal interferences in the nitric acid-sulfuric acid reagent blank for the microwave digestion of polymers figures in parentheses are percentage of natural abundance of isotope Elements 42K (6.9%) 42Ca (0.64%) 44Ca (2.1 %) 46Ti (8.0%) 48Ti (74.0%) 48Ca (0.2%) 49Ti (5.5 YO) "Ti (5.5%) "Cr (4.4%) 'OV (0.2%) 'lV (99.8%) 54Fe (5.8%) 54Cr (2.4%) 56Fe (91.7%) 57Fe (2.2%) '*Ni (67.8%) 58Fe (0.3%) 6%i (26.2%) 64Zn (48.8%) 64Ni (1.2%) 65Cu (30.9%) 66Zn (27.8 %) Interference 40Ar1H2 l2C'6O2 3 2 ~ 1 4 ~ 32s160 3 2 ~ 1 6 0 1 ~ - 3 3 ~ 1 6 0 34S160-33Sl601H 3 4 ~ 1 6 0 1 ~ 40Ar'4N 40Ar1601H nickel from cone/skimmer* nickel from cone/skimmer* 4 0 ~ ~ 1 6 0 32s1602-32s2 34s1602-32s34s 33~1602-32S160 1H * A platinum-tipped nickel cone and a nickel skimmer were used.monitored during analysis by ICP-MS in the multi-element semi-quantitative mode following microwave digestion. Detection limits were calculated as 3s where s is the standard deviation of the response for five blanks. Data for those elements occurring with a signal above the limit of detection are summarized in Table4 alongside the data generated by direct NAA (where available) and figures given are mean values for duplicate samples expresed as mg element kg - polymer material.Detection limits showed minor variation between batches of analysed samples so mean figures are given in Table 5. It should be noted that these detection limits were derived from background measurements and are considerably lower than levels of elements incorporated into the reference polymers (see below). If detection at approaching these limits was crucial (unlike in the present work) the system response at these concentrations would need to be investigated along with the linearity at these concentrations. In general and where detection limits permit comparison of data for the two multi-element methods indicates that agreement is generally within a factor of 2. Precision was generally ~ 1 0 % (for triplicate samples).In-house Polymer Reference Materials Analysis of the in-house polymer reference materials was performed in triplicate using the semi-quantitative ICP-MS method and background levels of elements in the virgm polymer were subtracted. Results are presented in Figs. 2 3 and 4 for ease of comparison with the nominal amounts of element incorporated and the data generated by the reference methods. All figures were corrected for reagent blank contri- butions. Mean precision figures for the quantitative ICP-MS (triplicate samples) and direct NAA (duplicate samples) for those elements which were not present in the base resin at comparable levels were 11 YO and 3% respectively (for all six elements in the five reference materials) suggesting that the distribution of elements was reasonable.Further analysis by LA-ICP-MS gave a mean precision figure of 10% for laser ablation at five surface sites. The HDPE reference material gave particularly good figures of 3 4 % for quantitative ICP-MS and 3-9% for LA-ICP-MS. As the HDPE virgin base resin was in the form of particularly fine powder optimum mixing in the compounder. was probably achieved for this material leading to superior distribution of the incorporated elements. The potential use of these polymer reference materials for quantitative analysis by LA-ICP-MS was investigated. A 'certified' value for the Co and Sb content of the PET reference material was calculated as the mean figure for the two quanti- tative methods (89 mg kg-' and 213 mg kg-l respectively). This calibrated material was then used as the reference for the determination of Sb and Co in a PET of unknown elemental composition.Comparison of the figures thus obtained by the other methods demonstrate that accuracy is good (Table 6). CONCLUSIONS 'The semi-quantitative multi-element ICP-MS method described here using microwave digestion sample preparation performs well where the requirements are wide elemental coverage and high sensitivity. However a few elements are subject to interferences which necessitates cautious interpret- ation of the data and the inherent sensitivity of the ICP-MS fechnique is negated to some degree by the sample dilution which accompanies digestion. Elimination of sulfuric acid for the digestion procedure would remove many interferences and this course is possible with less resistant polymers but the full range of polymers studied here demands the rigorous action of sulfuric acid to enable effective digestion.Alternatively the use of a high resolution instrument may resolve interferences. 306 Journal of Analytical Atomic Spectrometry April 1995 Vol. 10Table 4 Levels of elements (mg kg-l) in polymers intended for food contact applications as determined by semi-quantitative ICP-MS following microwave digestion and direct NAA Polymer A1 Cr Mn c o Zn Ge Zr Sb Pb LDPE I LDPE I1 LDPE I11 LDPE IV LLDPEt HDPE I HDPE I1 HDPE I11 HDPE IV HDPE V HDPE VI HDPE VII PP I PP I1 PP I11 PP IV PP-PES PS I PS I1 PS I11 PS IV PS v PS VI PS VII PET I PET I1 PMMA I$ PMMA I1 PMMA I11 AA-AN47 ABS” PS-PPOtt M A-AN-S* * ICP-MS nd * nd nd nd 23 nd nd nd nd nd nd nd nd nd nd nd 23 nd nd 23 nd nd nd nd nd 4.6 nd nd 5.4 130 220 nd nd NAA nd 8.6 nd nd 27 nd 3.7 4.8 5.7 7.8 nd nd nd nd nd nd 8.9 nd nd 46 nd nd nd nd nd 4.6 nd nd 6.5 190 260 nd 0.60 ICP-MS nd 8.6 nd nd 7.3 nd 13 nd 16 34 nd nd 22 26 26 13 110 18 nd nd nd nd nd nd nd 620 nd nd nd nd nd nd nd NAA nd nd 0.04 0.48 8.9’ 1.5 37 10 18 41 1.5 1.6 28 32 15 9.0 63 22 0.09 4.7 nd 0.05 0.04 0.06 nd 260 nd nd nd nd nd nd 11 ICP-MS NAA nd nd nd nd nd 3.0 nd nd nd nd nd 3.6 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 2.1 nd nd nd nd 2.0 2.6 nd nd nd 0.4 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd ICP-MS nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 0.18 0.53 nd nd nd nd nd nd nd NAA nd 0.007 nd 0.005 0.01 1 0.004 0.014 0.004 0.007 0.009 0.003 0.002 0.006 0.032 0.007 0.010 0.01 5 0.004 0.004 0.012 nd 0.005 0.006 0.005 0.11 0.27 nd nd 0.01 0.009 nd 0.02 0.009 ICP-MS NAA nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 0.05 0.59 nd nd nd nd nd nd 58 33 nd nd nd nd nd nd 0.42 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 0.54 nd nd nd nd nd nd 36 15 nd nd nd nd nd nd 0.35 ICP-MS nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 67 70 3.0 91 94 110 97 nd 1.2 nd nd nd nd 1.3 nd 50 NAA nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 33 57 nd 79 74 92 77 nd nd nd nd nd nd nd nd 35 ICP-MS NAA ICP-MS NAA nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 14 nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 13 nd nd nd nd nd nd nd nd nd nd nd nd nd 0.28 1.9 29 42 nd nd nd nd nd nd nd nd nd nd nd nd nd nd 0.08 0.20 nd nd nd nd nd nd nd ICP-MS nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 0.26 nd nd nd nd nd nd nd 160 230 nd nd nd nd nd nd 0.10 NAA nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd nd 0.003 140 170 nd nd nd nd nd nd 0.23 ICP-MS nd nd nd nd nd nd 1.9 4.1 0.38 0.37 nd 0.57 nd nd nd nd nd nd nd nd nd nd nd nd nd 0.24 nd nd nd 0.31 0.76 1 .o 3.5 ~ ~ * nd-none detected. t LLDPE-linear low density poly(ethy1ene).$ PP-PE-propylene-ethylene copolymer. $ PMMA-poly(methy1 methacrylate). 7 AA-AN-S-acrylic acid ester-acrylonitrile-styrene copolymer. l1 ABS-acrylonitrile-butadiene-styrene copolymer. ** MA-AN-S-methacrylic acid ester-acrylonitrile-styrene copolymer.tt PS-PPO-poly(styrene)-poly (phenylene oxide) mixed polymer.Table 5 Mean detection limits for multi-element semi-quantitative ICP-MS using microwave digestion sample pre-treatment Element Mg A1 Cr Mn co Zn Ge Zr Sb Pb Detection limit/mg kg-' 6 4 2 0.07 0.04 0.8 1 0.05 0.09 0.2 0 Nominal amount added 0 Quantitative ICP-MS Semiquantitative ICP-MS Quantitative NAA 140 120 - 100 ICn Y F 8o 60 ' 40 20 n LDPE HDPE PP PET PS 120 IM 95 I vv r 'a 80 F 60 3 40 20 Y _. n LDPE HDPE PP PET PS 100 r . . I - $ 80 6o * 40 20 Y 2. n " LOPE HDPE PP PET PS Fig. 2 Levels of incorporated elements (a) Mg; (b) Al; and (c) Cr in polymer reference materials Accuracy in the semi-quantitative mode is not exceptional but the method does achieve rapid multi-element analysis which is ideal for the screening of polymers for trace elements prior to fully quantitative analysis or migration experiments on targeted substances.Instrumentation is available at an ever- decreasing cost and improvements in accuracy may be possible by using alternative or a range of internal standards. The need for matrix-matched standards for the analysis of polymers by NAA and ICP-MS is frequently discussed and for LA they are virtually essential. Since certified reference materials were not available from the usual sources the need for comparison of data generated by the three basic analytical techniques reported here (ICP-MS NAA and LA-ICP-MS) necessitated the preparation of synthetic reference materials. Although not as satisfactory as commercial certified reference materials the results suggest that they provide a useful aid to validation of the methods described.Additional interlaboratory analyses are in progress aimed at further calibration. Such reference materials would have great utility now that recycling 140 120 7 lo) 100 Y (4 Nominal amount added Semiquantitative ICP-MS Quantitative NAA 0 Quantitative ICP-MS 80 !? 8o 3 8 o w 40 20 2 n PP PET PS LDPE HDPE 100 - L.. 80 b uu Y F * g 40 20 n PP PET PS " LDPE HDPE b Y 80 40 20 n PS LDPE HDPE PP PET Fig.3 Levels of incorporated elements (a) Co; (b) Zn; and (c) Sb in polymer reference materials 140 120 v b 100 Y F 80 A a 6 0 40 20 0 Fig. 4 CL Nominal amount added Semiquantitative ICP-MS 0 Quantitative ICP-MS PP PET PS LDPE HDPE Level of lead incorporated in polymer reference materials Table 6 Comparison of LA-ICP-MS data (mg kg-') for antimony and cobalt in PET I obtained using PET polymer reference material as calibrant Semi-quantitative Quantitative ICP-MS ICP-MS NAA LA-ICP-MS c o 58 42 36 33 Sb 158 168 136 166 issues generate new requirements to analyse plastics materials for metal species.The authors gratefully acknowledge the assistance of those European manufacturers which supplied the polymer samples required to undertake this work. REFERENCES 1 EEC (1992) Draft resolution on control of aids to polymerisation (technical adjuvants) for plastic materials intended to come into contact with foodstuffs. Adopted by the Committee of Ministers at the 482nd meeting on 19/10/92.2 Marshall J. and Franks J. Anal. Proc. 1990 27 240. 308 Journal of Analvtical Atomic SDectrometrv. A n d 1995 VOl. 103 4 5 6 7 8 9 10 11 12 13 14 15 Marshall J. Carroll J. Crighton J. S. and Barnard C. L. R. J. Anal. At. Spectrom. 1992 7 349R. Warren P. L. Anal. Proc. 1990 27 242. Warren P. L. Farges O. Horton M. and Humber J. J. Anal. At. Spectrom. 1987 2 245. Warren P. L. Anal. Proc. 1990 27 186. Olivier M. At. Absorpt. Newsl. 1971 10 12. Belarra M. A. Azofra M. C. Anzano J. M. and Castillo J. R. J. Anal. At. Spectrom. 1988,3 591. Belarra M. A. Anzano J. M. and Castillo J. R. Fresenius' 2 Anal. Chem. 1989 334 118. Vollkopf U. Lehmann R. and Weber D. J. Anal. At. Spectrom. 1987 2 455. Hieftje G. M. and Norman L. A. Int. J. Mass Spectrom. and Ion Processes 1992 118 J 119 5 19. Gray A. L. in Applications of ICP-MS ed. Date A. R. and Gray A. L. Blackie Glasgow and London 1989 ch. 1 p. 21. Ekimoff D. van Norstrand A. M. and Mowers D. A. Appl. Spectrosc. 1989 43 1252. Amarasiriwardena C. J. Gercken B. Argentine M. D. and Barnes R. M. J. Anal. At. Spectrom. 1990 5 457. Vaughan M.-A. Baines A. D. and Templeton D. M. CEin. Chem. 1991,37 210. 16 17 18 19 20 21 22 23 24 Gray A. L. Analyst 1985 110 551. Denoyer E. R. Fredeen K. J. and Hager J. W. Anal. Chem. 1991,63 445A. Marshall J. Franks J. Abell I. and Tye C. J. Anal. At. Spectrom. 1991 6 145. Ward N. I. Durrant S. F. and Gray A. L. J. Anal. At. Spectrom. 1992 7 1139. Kennedy G. C. in Symposium Proceedings Metallization of Polymers Montreal Sept. 24th-28th 1989 ed. Sacher E. Pireaux J.-J. and Kowalczyk S. P. Div. Polymer Chem American Chemical Society 1990 pp. 128-134. Matsuyama T. Matsushita R. Yamaoka H. Nemoto H. and Shirakawa H. J. Phys. SOC. Jpn. 1984 53 3688. Kolomi'tsev M. A. Ambardanashvili T. S. and Dundua V. Yu. J. Radioanal. Chem. 1974 20 549. Rakovskii 8. E. Krylova T. D. Kuligin V. M. Bol'shakova L. I. Myasoedova G. V. and Savvin S. B. J. Anal. Chem. USSR (Engl. Transl.) 1980 35 1553. Tan S. H. and Horlick G. Appl. Spectrosc. 1986 40 445. Paper 4/04877F Received August 9 1994 Accepted November 21 1994 journal of Analytical Atomic Spectrometry April 1995 Vol. 10 309

ISSN:0267-9477    

DOI:10.1039/JA9951000303

出版商:RSC    

年代:1995

数据来源: RSC