Journal of Analytical Atomic Spectrometry (Including Atomic Spectrometry Updates) JAAS Editorial Board* Chairman L Ebdon (Plymouth UK) J Egan (Cambridge UK) D A Hickman (London UK) B L Sharp (Loughborough UK) J Marshall (Middlesbrough UM J M Mermet (Villeurbanne France) D L Miles (Keyworth UK) R D Snook (Manchester UK) *The JAAS Editorial Board reports to the Analytical Editorial Board Chairman A G Fogg (Loughborough UM F C Adams (Antwerp Belgium) R M Barnes (Amherst MA USA) L Bezur (Budapest Hungary) R F Browner (Atlanta GA USA) S Caroli (Rome Italy) A J Curtius (Rio de Janeiro Bran4 L de Galan (Vlaardingen The Nether J B Dawson (Leeds UM K Dittrich (Leipzig GDR) W Frech (Umed Sweden) K Fuwa (Tokyo Japan) A L Gray (Egham UK) JAAS Advisory Board S Greenfield (Loughborough UK) G M Hieftje (Bloomingron IN USA) G Horlick (Edmonton Canada) B V L'vov (Leningrad USSR) Ni Zhe-ming (Beiling Chrna) N Omenetto (Ispra Italy) lands) T C Rains (Charleston SC USA) R E Sturgeon (Ottawa Canada) R Van Grieken (Antwerp Belgium) A Walsh K B (V/ctoria Austraha) B Welz (Uberlingen FRG) T S West (Abderdeen UM ~~ ~ Atomic Spectromery Updates Editorial Board Chairman *D L Miles (Keyworth UK) J Armstrong (Oumfries UM H Matusiewicz (Poznan Poland J R Bacon (Aberdeen UK) J M Mermet (Vrlleurbanne France) C Barnard (Glasgow UK) R G Michel (Storrs CT USA) R M Barnes (Amherst MA USA) T Nakahara (Osaka Japan) S Branch (High Wycombe UK) Ni Zhe-ming (Beyng China) R Bye (Oslo Norway) P R Poole (Hamilton New Zealand) J Carroll (Middlesbrough UK) W J Price (Ashburton UK) M R Cave (Keyworth UK) C J Rademeyer (Pretoria South Africa) M H Ramsey (London UK) A Sanz-Medel (Oviedo Spain) H M Crews (Norwch UK) I L Shuttler (Uberlingen FRG) J S Crighton (Sunbury-on-Thames UK) S T Sparkes (Plymouth UK) R Stephens (Halifax Canada) J R Dean (Newcastle upon Tyne UK) J Stupar (Ljubljana Yugoslavra) R E Sturgeon (Ottawa Canada) "J M Cook (Keyworth UK) "M S Cresser (Aberdeen UKI "J B Dawson (Leeds UkI "L Ebdon (Plymouth UK) *J Egan (Cambridge UK) A Taylor (Gurldford UK) *A T Ellis (Oxford UM A P Thorne (London UK) "D J Halls (Glasgow UK) "D A Hickman (London UK) "A M Ure (Aberdeen UK) "S J Hill (Plymouth UK) S J Walton (Crawley UK) P Watkins (London UK) B Welz (Uberlingen FRG) J Williams (Eghan UK) J B Willis (Victorra Australia) J Fazakas (Bucharest Romania) G C Turk (Gaithersburg MD USA) J F Tyson (Amherst MA USA) K W Jackson (Albany NY USA) R Jowitt (Middlesbrough UK) K Kitagawa (Nagoya Japan) "D Littlejohn (Glasgow UK) "J Marshall (Middlesbrough UK) *Members of the ASU Executive Committee Editor JAAS Judith Egan The Royal Society of Chemistry Dr J M Harnly Thomas Graham House Science Park Milton Road Cambridge CB4 4WF UK Telex No 81 8293 Fax 0223 423623 Assistant Editors Brenda H ol I Ida y Editorial Secretary Monique Warner US Associate Editor JAAS US Department of Agriculture Beltsville Human Nutriton Research Center Beltsville MD 20705 USA Telephone 301 -344-2569 Telephone 0223 420066 BLDG 161 BARC-EAST Paula O'Riordan Sheryl Whitewood Advertisements Advertisement Department The Royal Society of Chemistry Burlington House Piccadilly London W1V OBN UK.Telephone 071-437 8656. Fax 071-437 8883 Information for Authors Full details of how to submit materials for publica- tion in JAAS are given in the Instructions to Authors in Issue 1 Separate copies are available on reauest The Journal of Analytical Atomic Spectrometry (JAAS) is an international journal for the publica- tion of original research papers communications and letters concerned with the development and analytical application of atomic spectrometric techniques The journal is published eight times a year including comprehensive reviews of specific topics of interest to practising atomic spectrosco- pists and incorporates the literature reviews which were previously published in Annual Reports on Analytical Atomic Spectroscopy (ARAAS) Manuscripts intended for publication must de- scribe original work related to atomic spectromet- ric analysis Papers on all aspects of the subject will be accepted including fundamental studies novel instrument developments and practical ana- lytical applications As well as AAS AES and AFS papers will be welcomed on atomic mass spectro- metry and X-ray fluorescencelemission spectro- metry Papers describing the measurement of molecular species where these relate to the char- acterization of sources norrnally used for the pro- duction of atoms or are concerned for example with indirect methods of analysis. will also be ac- ceptable for publication Papers describing the de- velopment and applications of hybrid techniques (e g GC-coupled AAS and HPLC-ICP) will be par- ticularly welcome Manuscripts on other subjects of direct interest to atomic spectroscopists.in- cluding sample preparation and dissolution and analyte pre-concentration procedures as well as the statistical interpretation and use of atomic spectrometric data will also be acceptable for pub- lication There is no page charge The following types of papers will be consid- ered 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 Revlews which must be a critical evaluation of the existing state of knowledge on a particular facet of analytical atomic 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 rnanu- script will be regarded as an undertaking that the same material is not being considered for publica- tion by another journal Manuscripts (three copies typed in double spacing) should be sent to Judith Egan.Editor. JAAS or Dr J M Harnly US Associate Editor. JAA S All queries relating to the presentation and sub- mission of papers and any correspondence re- garding 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 eight times a year 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 Tractions Ltd Blackhorse Road Letchworth Herts SG6 1 HN UK.Tel +44 (0) 462 672555 Telex 825372 Turpin G. Fax +44 (0) 462 480947 Turpin Transactions Ltd is wholly owned by The Royal Society of Chemistry 1991 Annual subscription rate EC €309 00 USA $728 00 Rest of World f355 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 11003 USA Postmaster send address changes to Journal of Analytical Atomic Spectrometry (JAASI Publications Expediting Inc 200 Meacham Avenue Elmont NY 11003 Second class 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 0 The Royal Society of Chemistry 1991 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 publishersJournal of Analytical Atomic Spectrometry (Including Atomic Spectrometry Updates) JAAS Editorial Board* Chairman L Ebdon (Plymouth UK) J Egan (Cambridge UK) D A Hickman (London UK) J Marshall (Middlesbrough UM R D Snook (Manchester UK) J M Mermet (Villeurbanne France) D L Miles (Keyworth UK) B L Sharp (Loughborough UK) *The JAAS Editorial Board reports to the Analytical Editorial Board Chairman A G Fogg (Loughborough UK) F C Adams (Antwerp Belgium) R M Barnes (Amherst MA USA) L Bezur (Budapest Hungary) R F Browner (Atlanta GA USA) S Caroli (Rome Italy) A J Curtius (Rio de Janeiro Brazil) L de Galan (Vlaardingen The Nethei J B Dawson (feeds UK) K Dittrich (Leipag GDR) W Frech (Umed Sweden) K Fuwa (Tokyo Japan) A L Gray (Egham UK) JAAS Advisory Board S Greenfield (Loughborough UK) G M Hieftje (Bloommgton IN USA) G Horlick (Edmonton Canada) B V L'vov (Leningrad USSR) Ni Zhe-ming (Beiling Cnma) N Omenetto (lspra Italy) -lands) T C Rains (Charleston SC USA) R E Sturgeon (Ottawa Canada) R Van Grieken (Antwerp Belgium) A Walsh K B (Victoria Australia) B Welr (Uberlingen FRG) T S West (Abderdeen UK) Atomic Spectromery Updates Editorial Board Chairman "D L J Armstrong (Dumfries 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) *J M Cook(Keyworth UK) "M S Cresser (Aberdeen UK) H M Crews (Norwich UK) J S Crighton (Sunbury-on-Thames UK) J R Dean (Newcastle upon Tyne UK) * J B Dawson (Leeds Ukl "L Ebdon (Plymouth UK) "J Egan (Cambridge UK) *A T Ellis (Oxford UK) "D J Halls (Glasgow UK) *D A Hickman (London UK) "S J Hill (Plymouth UK) J Fazakas (Bucharest Romania) K W Jackson (Albany NY USA) R Jowitt (Middlesbrough UK) K Kitagawa (Nagoya Japan) "D Littlejohn (Glasgow U;c) "J Marshall (Middlesbrough UK) Miles (Keyworth UK) H Matusiewicz (Poman Poland) J M Mermet (V/lleurbanne France) R G Michel (Storrs CT USA) T Nakahara (Osaka Japan) Ni Zhe-ming (Beying China) P R Poole (Hamilton New Zealand) W J Price (Ashburton UK) C J Rademeyer (Pretoria South Africa) M H Ramsey(London UK) A Sanz-Medel (Owedo Spain) I L Shuttler (Uberlmgen FRG) S T Sparkes (Plymouth UK) R Stephens (Halifax Canada) J Stupar (Llublpna Yugoslawa) R E Sturgeon (Ottawa Canada) A Taylor (Guildford UK) A P Thorne (London UK) G C Turk (Gaithersburg WD USA) J F Tyson (Amherst MA USA) "A M Ure (Aberdeen UK) S J Walton (Crawley UK) P Watkins (London UK) B Welz (Uberlingen FRG) J Williams (Eghar, UK) J B Willis (Victoria Australia) *Members of the ASU Executive Committee Editor JAAS Judith Egan The Royal Society of Chemistry Thomas Graham House Science Park Milton Road Cambridge CB4 4WF UK Telex No 818293 Fax 0223 423623 Assistant Editors Brenda Holliday Editorial Secretary Monique Warner US Associate Editor JAAS Dr J M .Harnly US Department of Agriculture Beltsville Human Nutriton Research Center Beltsville M D 20705 USA.Telephone 301 -344-2569 Telephone 0223 420066 BLDG 161 BARC-EAST Paula O'Riordan Sheryl Whitewood Advertisements Advertisement Department The Royal Society of Chemistry Burlington House Piccadilly London WIV OBN UK Telephone 071-437 8656. Fax 071-437 8883 Information for Authors Full details of how to submit materials for publica- tion in JAAS are given in the Instructions to Authors in Issue 1 Separate copies are available on reauest The Journal of Analytical Atomic Spectrometry (JAAS) is an international journal for the publica- tion of original research papers communications and letrers concerned with the development and analytical application of atomic spectrometric techniques The journal is published eight times a year including comprehensive reviews of specific topics of interest to practising atomic spectrosco- pists and incorporates the literature reviews which were previously published in Annual Reports on Analytical Atomic Spectroscopy ( AR AAS) Manuscripts intended for publication must de- scribe original work related to atomic spectromet- ric analysis Papers on all aspects of the Subject will be accepted including fundamental studies novel instrument developments and practical ana- lytical applications As well as AAS AES and AFS.papers will be welcomed on atomic mass spectro- metry and X-ray fluorescence/emission spectro- metry Papers describing the measurement of molecular species where these relate to the char- acterization of sources normally used for the pro- duction of atoms or are concerned for example with indirect methods of analysis will also be ac- ceptable for publication Papers describing the de- velopment and applications of hybrid techniques (e g GC-coupled AAS and HPLC-ICP) will be par- ticularly welcome Manuscripts on other Subjects of direct interest to atomic spectroscopists.in- cluding sample preparation and dissolution and analyte pre-concentration procedures as well as the statistical interpretation and use of atomic spectrometric data will also be acceptable for pub- lication There is no page charge The following types of papers will be consid- ered Full papers describing original work Commumcations 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 atomic spectrometry Every paper (except Communications) will be submitted to at least two referees by whose advice tne 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 manu- script will be regarded as an undertaking that the same material is not being considered for publica- tion by another journal Manuscripts (three copies typed in double spacing) should be sent to Judith Egan Editor JAAS or Dr J M Harnly US Associate Editor JAAS All queries relating to the presentation and sub- mission of papers and arty correspondence re- garding 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) I S published eight times a year 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 t o The Royal Society of Chemistry.Turpin Tractions Ltd Blackhorse Road Letchworth Herts SG6 1 HN UK Tel +44 (0) 462 672555 Telex 825372 Turpin G Fax +44 (0) 462 480947 Turpin Transactions Ltd IS wholly owned by The Royal Society of Chemistry 1991 Annual subscription rate EC €309 00 USA $728 00 Rest of World €355 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 11003 USA Postmaster send address changes to Journal of Analytical Atomic Spectrometry (JAAS) Publications Expediting Inc 200 Meacham Avenue Elmont NY 11003 Second class 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 2 The Royal Society of Chemistry 1991 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