摘要:

Proceedings of the Society for Analytical Chemistry Analytical Division Chemical Society Proc. SOC. Analyt. Chem. Vol. 9 No. 5 Pages 103-122 CONTENTS Reports of Meetings . . . . Chromatography and Electro- Assessment of Toxic Effects phoresis Group . . .. 03 04 upon Marine Invertebrates 105 Summaries of Papers “Geological Applications of Particle Size Analysis” . I I5 “Auger Spectroscopy”. . . . 118 “Carbon in Effluents” . . . . 120 Papers Accepted for The Analyst I2 I Publications Received .. .. 121 Short Courses . . . . . . 122 Forthcoming Meetings Back Cover May 1972 PAYCAL Vol. 9 No. 5 May 1972 PROCEEDINGS OF THE SOCIETY FOR ANALYTICAL CHEMISTRY ANALYTICAL DIVISION CHEMICAL SOCIETY Hon. Secie!ory W. H. C. Shaw Officers of The Society for Analytical Chemistry and the Analytical Division of The Chemical Society C.Whalley President Hon. Treasurer G. W. C. Milner HXI. Assistant Socretaries D. I. Coomber; D. W. Wilscn Secretory Miss P. E. Hutchinson 9/10 SAVILE ROW LONDON WIX IAF Telephone 01-734 9864 Editor J. B. Attrill Assistant Editor P. C. Westoil Proceedings i s published by The Society for Analytical Chemistry and distributed t o all members of the Analytical Division and t o subscribers with The Analyst; subscriptions cannot be accepted for Proceedings alone. Single copies can be obtained direct from The Chemical Society Publications Sales Ofice Blackhorse Road Letchworth Herts. SG6 I H N (NOT through Trade Agents) price 25p. post free. Remit ances MUST accompany orders. 0 The Society for Analytical Chemistry Radiochemical Methods Group Microchemical Methods Group Automatic Methods Group Electroanalytical Methods Group Chromatography and Electrophoresis Group A Joint Meeting of the above Groups will be held a t the University of Kent Canterbury Kent Thursday and Friday September 14th and 15th 1972 on The subject of the Meeting w i l l be Chemical Analysis and the Environment Scientific Sessions-Scientific sessions dealing with Chemical Analysis and Air Pollution Water Pollution and other aspects such as pesticide analysis have been arranged.Accommodation-Accommodation has been arranged i n Eliot College of t h e University. Visits-Visits are being arranged to local research centres tor which coaches will be The numbers for t h e visits may have to be restricted. Application forms will be circulated with the August issue of Proceedings. Application forms will also be available from Miss P. E. Hutchinson Society for Analytical Chemistry 9/10 Savile Row London WIX IAF. provided.

ISSN:0037-9697    

DOI:10.1039/SA97209FX017

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

SOCIETY FOR ANALYTICAL CHEMISTRY ANALYTICAL DIVISION CHEMICAL SOCIETY Forthcoming Meetings-continued from back cover June-continued “The Analysis of Impurities in Inorganic Matrices by Flameless Atomic Absorption Spectrophotometry,” by C. W. Fuller. “Combined Electrolysis and Atomic Absorption for the Extraction and Deter- mination of Metals in Biological Materials,” by T. F. Hartley and D. J. Ellis. Plenavy Lectuve-“Selectivity in Trace Analysis the Detection and Estimation of Compounds,” by H. Egan. “Some Sources of Contamination in Trace Analysis,” by R. 0. Scott and A. M. Ure . “Practical Improvements in the Selectivity of Neutron Activation Analysis,” by R. F. Coleman. “Problems in the Determination of Oxygen in Steel by Reducing Fusion,” by G. D. Hall. “Programmed Elution Thin-layer Chromatography as a Technique in the Selective Analysis of Phenols,” by J.M. Philp. “Trace Analysis by GC - MS,” by E. Clayton. “Pitfalls in the Measurement of Drug Availability,” by J . P. Glynn. “A New Gas Chromatography Detector Tunable to a Wide Range of Elements,” by W. R. McLean D. L. Stanton and G. E. Penketh. “Spark Source Mass Spectrometry,” by K. B. Wrigley. “Some Applications of Heteropoly Acids for Amplification Procedures in Atomic Absorption Spectroscopy,’’ by H. N. Johnson G. F. Kirkbright and Professor T. S. West. “Trace Metal Analysis in the Sub-nanogram Range Using Anodic Stripping Voltammetry,” by I. Fraser. The University Stirling. NORTH WEST REGION AUTOMATIC METHODS and ELECTROANALYTICAL GROUPS “Water-insoluble Enzymes,” by Professor S. A. Barker. “Enzyme Electrodes,” by B.Fleet. “Use of Enzymes in Automatic Analysis,” by D. B. Roodyn. “Trace Analysis by Enzyme Inhibition and Activation,” by A. Townshend. Room 918 Maxwell Building The University Salford; 11.15 a.m. Tuesday 27th SALFORD on “The Use of Enzymes in Analysis.” SOCIETY FOR ANALYTICAL CHEMISTRY ANALYTICAL DIVISION CHEMICAL SOCIETY May Thursday 25th LONDON Friday 26th NORWICH June Friday 2nd LONDON Thursday 8th LONDON Saturday 10th Wednesday 21st to Friday 23rd STIRLING Forthcoming Meetings BIOLOGICAL METHODS GROUP. “Statutory Requirements for Toxicological Examination and Control of Plastics,” by D. W. Plester. “Practical Problems in Examination and Control of Plastics for Pharma- ceutical Use,” by J. E. Pentelow. The Pharmaceutical Society 17 Bloomsbury Square London W.C.1 ; 2.30 p.m. (Please note In the April issue of Proceedings the venue for this meeting was EAST ANGLIA REGION on “Safety and Legal Aspects of Food Additives.” “Determination of Traces of Toxic Metals in Foodstuffs by Atomic Absorption “Analytical Aspects of Food Additives and Packaging,” by I. E. Burrows. “Packaging Legislation-Some Analytical Requirements,” by M. W. Robertson. Lecture Theatre Block University Plain University of East Anglia Norwich ; wrongly advertised as Imperial College.) Spectroscopy,” by G. Nelson and D. L. Smith. 2.30 p.m. ELECTROANALYTICAL GROUP. “Developments and Trends in Analytical Research and Instrumentation,” by Lecture Theatre D Chemistry Department Imperial College London S.W.7 ; JOINT PHARMACEUTICAL ANALYSIS GROUP. Discussion on “Original Papers.” Pharmaceutical Society of Great Britain 17 Bloomsbury Square London WESTERN REGION.Summer Meeting. SCOTTISH NORTH WEST and NORTH EAST REGIONS with MICROCHEMICAL METHODS ATOMIC SPECTROSCOPY CHROMATOGRAPHY AND ELECTROPHORESIS and RADIOCHEMICAL METHODS GROUPS on “Selectivity in Trace Analysis.” Discussion on “Detection Limits” to be introduced by G. F. Kirkbright and Plenary Lecture-“Selectivity in Trace Element Analysis,” by A. A. Smales “Automatic Hollow-cathode Analysis for Trace Elements in High Temperature “The Determination of Small Amounts of Aluminium in Steel by Atomic “The Use of Separation Procedures for Atomic Absorption Spectroscopy in “Some Factors Governing Limits of Detection in Separation Systems,” by “2-Alkyl-substituted Quinolinols as Solvent Extraction Agents,” by F. R. “Auto-oxidation of Stilbenes ’’ by P. Spahr and E. V. Truter. “Selectivity in the Application of Activation Techniques Based on the Measure- ment of Prompt Radiation Emitted During Charged-particle Irradiation ’’ by T. B. Pierce. “The Mass-spectrometric Determination of Small Amounts of Gases Particu- larly in Coated Particle Fuels,” by J. W. McMillan B. L. Taylor and G. J. Weldrick. [continued inside back covey J. B. Flato. 1.30 p.m. W.C. 1 ; 4 p.m. D. A. Pantony. Alloys,” by K. Thornton. Absorption Spectroscopy ” by R. H. Jenkins. Clinical Chemistry,” by H. T. Delves. R. R. Goodall. Haba G. H. Kazi and D. A. Pantony. Printed by W Heffer & Sons Ltd Cambridge England

ISSN:0037-9697    

DOI:10.1039/SA97209BX019

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

May 1972 Vol. 9 No. PROCEEDINGS OF THE SOCIETY FOR ANALYTICAL CHEMISTRY ANALYTICAL DIVISION CHEMICAL SOCIETY Reports of Meetings SCOTTISH REGION A JOINT Meeting of the Region with the Glasgow and West of Scotland Section of the CS was held at 4 p.m. on Monday April 17th 1972 in the Department of Chemistry University of Strathclyde Cathedral Street Glasgow C.l. The Chair was taken by the T’ice-Chairman of the Glasgow and West of Scotland Region of the CS Dr. G. R. Jamieson. A lecture on “Modern Methods of Functional Group Analysis” was given by Professor S. Siggia. WESTERN REGION AND PARTICLE SIZE ANALYSIS GROUP A JOINT Meeting of the Western Region and the Particle Size Analysis Group was held at 2.30 p.m. on Wednesday April 26th 1972 in the Chemistry Department The IJniversity Clifton Bristol.The Chair was taken by the Vice-chairman of the Particle Size Analysis Group Dr. M. J. Groves. The subject of the meeting was “Local Interests in Powder Characterisation” and the following papers were presented and discussed “Particle Sampling in a Chimney Plume Visibility Study,” by R. T. Jarman; “Surface Area and Particle Size Measurements on Alumina,” by W. T. Hughes; “The Effect of Pigment Particle Size on Printing Ink Proper- ties,” by D. Carr; “The Determination of Particle Size Distributions for Kaolin and Other Minerals,’’ by L. F. Gate. NORTH EAST REGION AND CHROMATOGRAPHY AND ELECTROPHORESIS GROUP A JOINT Meeting of the North East Region and the Chromatography and Electrophoresis Group with the Liquid Chromatography Sub-Group of the Gas Chromatography Discussion Group of the Institute of Petroleum was held at 2.30 p.m.on Thursday April 20th 1972 in the School of Chemistry The University Newcastle upon Tyne. The Chair was taken by the Chairman of the North East Region Mr. A. E. Heron. The subject of the meeting was “High Performance Liquid Chromatography in Columns” and the following papers were presented and discussed “Instrumentation for High Efficiency Liquid Chromatography,’ ’ by T. Wilkins ; “Use of Polarographic Detectors in Liquid Chroma- tography,” by R. J. Maggs (read by Mrs. D. Simpson); “Some Applications of Organic Chemical Analysis by High Pressure Liquid Chromatography by N. A. Parris. ATOMIC SPECTROSCOPY GROUP AN Ordinary Meeting of the Group was held at 10.30 a.m. on Wednesday April 12th 1972 in the Chemistry Department University of Keele.The Chair was taken by the Chairman of the Group Mr. W. R. Nall and by Mr. H. Bennett of the British Ceramic Research Asso- ciation. The subject of the meeting was “Atomic Spectroscopy in Ceramic Analysis,” and the speakers were A. D. Ambrose R. Julietti P. D. Salt G. Oliver and J. H. Rigby. THERMAL ANALYSIS GROUP THE third Thermal Analysis School organised by the Group was held on Monday April 17th to Friday April 21st 1972 in the Industrial Materials Research Unit Queen Mary College Mile End Road London El 4NS. During the course of the School the following lecture programme was given “Introduc- tion to Thermal Analysis,” by J. P. Redfern; “Theoretical Basis for Thermal Analysis,” by D. Dollimore; “Thermodynamic Properties of Polymers,” by R. C. Roberts; “Kinetic Parameters from Thermal Analysis Data,” by K.E. J. Barrett; “Applications to Fats and 103 104 CHROMATOGRAPHY AND ELECTROPHORESIS GROUP [Proc. SOC. AnaZyt. Chem. Waxes and in the Petroleum Industry,’ by I. C. Wylie; “Thermal Degradation of Polymers,” by Professor D. A. Smith ; “Applications to Plastics Rubbers Fibres Paints Adhesives and Composites,” by A. R. Westwood; “Evolved Gas Analysis,” by J. W. Youren; “Applica- tions to Pharmaceuticals Agricultural Chemicals and Foodstuffs,” by R. E. Waller. AUTOMATIC METHODS GROUP AND EDUCATION AND TRAINING GROUP A JOINT Discussion Meeting of the Automatic Methods and the Education and Training Groups was held at 2.30 p.m. on Thursday April 27th 1972 in the Scientific Societies Lecture Theatre 23 Savile Row London W.l. The Chair was taken by the Chairman of the Auto- matic Methods Group Dr. J. M. Skinner. A discussion on “Analytical Chemistry-the Need for Interdisciplinary Training” was introduced by G. E. Penketh and J. K. Foreman. ELECTROANALYTICAL GROUP A DISCUSSION Meeting of the Group was held at 6.30 p.m. on Thursday April 27th 1972 in the Senior Common Room Imperial College London S.W.7. The Chair was taken by the Chairman of the Group Mr. J. V. Westwood. A discussion on “Trends in Electroanalysis” was introduced by P. 0. Kane A. E. Bottom R. D. Jee R. Briggs and D. Band.

ISSN:0037-9697    

DOI:10.1039/SA9720900103

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

104 CHROMATOGRAPHY AND ELECTROPHORESIS GROUP [Proc. SOC. AnaZyt. Chem. The Chromatography and Electrophoresis Group IN April 1964 the inaugural meeting of the Thin-Layer Chromatography Group took place under the Chairmanship of Dr. E. V. Truter. Prior to this date the Group had been known as the Thin-Layer Chromatography Discussion Panel of the Physical Methods Group. In 1968 the scope of the Group was broadened to include all aspects of chromatography and related techniques and it was given the name of the Chromatography and Electro- phoresis Group. Meetings on topics of interest are held three or four times each year in different parts of the country often as Joint Meetings with other Groups and/or Regions. They may be in the form of evening discussion meetings or half-day full-day or two to three-day events in which may be included lectures demonstrations and exhibitions.An attempt is made to hold meetings in all parts of the United Kingdom. Places at which they have been held in the past include Birmingham Bristol Cardiff Derby Edinburgh Ipswich Leeds Leicester Nottingham Paisley Portsmouth and of course London. I t has become the custom to hold the Annual General Meeting of the Group in London. Other locations envisaged for future meetings include Newcastle upon Tyne Stirling Canterbury and Dundee. The Committee is always very pleased to receive suggestions about possible future topics and locations for meetings. An attempt has always been made to have a Committee comprising representatives from both industrial and academic fields and from as many different areas of the United Kingdom as possible.The present Committee for instance has members from academic establish- ments research organisations and from the plastics petroleum and pharmaceutical industries. Geographical areas covered by them include Berkshire Bristol Essex Kent London Nottinghamshire and Yorkshire. The first Chairman of the Group was Dr. E. V. Truter and the first Honorary Secretary Dr. I. Smith but as Dr. Smith’s work took him overseas for a lengthy period his place was taken by the Acting Honorary Secretary Mr. F. W. S. Carver. In 1966 Mrs. D. Simpson was elected as Honorary Secretary/Treasurer which position she still holds. Chairmen of the Group have been- Dr. E. V. Truter . . . . . . 1964-1966 Mr. J. D. R. Thomas . . . . 1966-1968 Dr. I. Smith . . . . . . 1968-1969 Professor E. T. Shellard . . 1969-1971 May 19721 ASSESSMENT OF TOXIC EFFECTS UPON MARINE INVERTEBRATES The present Officers of the Group are- Dr. E. V. Truter . . Chairman Mr. J. W. Murfin . . Vice-chairman Mrs. D. Simpson . . Honorary Secretary/Treasurer 106 Dr. B. V. Truter Mr. J . W. Murfin Mrs. D. Simpson At the end of 1971 the Group had 837 members and it is expected that this number will be increased considerably following the formation of the new Chemical Society having the Analytical Division of which the Group is a part. It is hoped that such an increase in membership will extend the activities of the Group still further perhaps resulting in a conference from time to time.

ISSN:0037-9697    

DOI:10.1039/SA9720900104

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

May 19721 ASSESSMENT OF TOXIC EFFECTS UPON MARINE INVERTEBRATES 106 Some Methods of Assessment of Toxic Effects upon Marine Invertebrates* BY E. J. PERKINS ( University of Strathclyde Department of Biology Marine Laboratory Dalandhui Hoztse Garelochhead Dunbartonshire Scotland) Studies of the toxic effect of effluents and other materials upon a range of marine invertebrate animals are considered. It has been shown that simple TLm studies are inadequate. Many criteria other than death in short- term studies are relevant to these problems. By undertaking improvements in techniques such studies including those in the really long term can be undertaken. IT is I think worth stating at the outset that the approach of myself and co-workers to the problem of toxic events in tbe marine environment is that of an ecologist rather than that of a physiologist.Here ecology is considered in terms of quantitative field studies of marine populations in relation to the measured parameters of their environinent-biological chemical and physical. Strictly speaking however laboratory investigations in support of such field studies m?y be classified as physiology rather than ecology. In this context it is evident that while ecology may provide clues to the understanding of an environmental situation and any experimental information acquired must make sense in terms of the situation in the environ- ment a purely ecological approach cannot wholly provide an understanding of an environ- mental problem. This conclusion led to the development of studies in toxicity to be performed concurrently with whatever effluent was under field investigation by this laboratory.*Based on a paper presented a t a meeting of the Biological Methods Group held on October 29th 1970 and reported in the December 1970 issue of Proceedings @. 213). 106 ASSESSMENT OF TOXIC EFFECTS UPON MARINE INVERTEBRATES [Proc. SOC. AnaZyt. Chem. Early experimental work produced highly variable results and such anomalies as 100 per cent. death in controls accompanied by little death in the treated animals. Of course all experimental physiologists including toxicologists are aware of the need to have their experimental animals in an unstressed condition i.e. a “normal” physiological state but such results are clearly too ridiculous to be explained by the statement that all biological material is variable.If it is accepted that some inherent variability must occur in the test animals chosen there seems to be no good reason why the standards deemed to be necessary in chemical analytical techniques should not be applied to marine toxicity studies. Having reached such a conclusion it is possible to eliminate systematically those factors which produce poor results. Unlike mammalian studies workers in the marine invertebrate field face a number of problems peculiar to the marine situation. The inability to culture most marine animals satisfactorily means that with few exceptions work is carried out with animals brought in from the wild and taken from conditions unlike the laboratory. Care in handling both during collection and in transport to the laboratory is vital-animals that are dredged and trawled may show “capture stimuli” vix.increased mortality repetitive moulting and stimulation of cannibalism which hand-collected stock do not. Overcrowding during trans- port may produce similar undesirable effects. It is essential to recognise that attention should be paid to the physiological requirements and migrations of test species as the latter may result from a response to fulfil the needs of the former. Such precautions alone facilitate the performance of really long-term experiments i.e. up to or exceeding 1 year.l When such information has been available in the past studies of toxicology with respect to marine animals and to invertebrates in particular have relied predominantly upon extreme or acute exposures followed by no or relatively short recovery periods e.g.up to 5 days. In general the experimental conditions have been poorly defined with no definition of the hand- ling selection and acclimation procedures adopted. While the best of these studies vix. the methods adopted by the Federal Water Pollution Control Administration of the U.S. Depart- ment of the Interior 1965 have great value they are nevertheless highly stylised concerned predominantly with fish and despite great precision in defining conditions a t the time of exposure to toxic entities do not define the other conditions of equal importance prior to the exposure. However even in the most clearly defined conditions median tolerance limit determinations are inadequate,2 and have little direct relevance to fisheries. Even today with the exception of work at Narragansett little effort has been expended upon longer-term chronic studies and the whole field is in a very primitive state compared with medical toxi- Median tolerance limit TLm studies are preoccupied with the death or survival of the test organisms and ecological literature has made much use of lethal i.e.death under TLm conditions and sub-lethal (sub-TL,) effects. In general these conditions are poorly defined as what is apparently a sub-lethal condition in the short term ‘oix. 1 week may be lethal in the long term e.g. 1 month or 1 year. Moreover lethality itself requires some definition. An acute toxicity test i.e. a TLm test may kill the test organisms at one of three stages viz. during the actual period of exposure to the toxin during the 5-day or other designated short- term recovery period or after some considerable delay during which time the animal has apparently recovered its normal health.The last effect has been noted in polychaete larvae3 and shore-dwelling gastropod molluscs4 exposed to oil emulsifier formulations. It would seem reasonable to distinguish between these stages of mortality thus ( a ) comomitant mortality a term to be used with reference to death that occurred during the period of exposure to toxin; (b) consequential mortality a term to be used when a mortality pattern develops in the recovery period after the exposure to toxin and when the same pattern develops continuously in the days that follow immediately after the recovery period; and (c) delayed mortality a term to be used with reference to mortality that supervenes after a period during which the animals have appeared to be healthy and in which none have died.Clearly some substances may evoke all three responses depending upon the concentration to which the test animals are exposed. The oil emulsfiers of the B.P. 1002 type had this characteristic and in this instance once the delayed mortality had become overt the effect was noted over a protracted period. The most dangerous substances are clearly those which show neither concomitant nor consequential mortality effects but may kill or produce gross effects after a period of delay that may be days weeks or longer-in humans such effects are noted in individuals exposed to substances such as radium asbestos beryllium and tolylene isocyanate. cology. May 19721 ASSESSMENT OF TOXIC EFFECTS UPON MARIKE INVERTEBRATES 107 In essence the lethal effect particularly that in acute treatments is relatively easy to define although it may be much delayed.The sub-lethal (i.e. sub-TL,) effect however is much more difficult to define particularly in marine invertebrates if only because of the problems involved in long-term maintenance which are particularly related to chronic expo- sure studies. The crux of this problem lies in the uncertainty of what truly constitutes a sub- lethal concentration although anticipating what will be said below J. R. s. Gilchrist of this laboratory has shown recently that upon chronic exposure to an effluent concentration that was apparently sub-lethal 100 per cent. of Asterias rubens (starfish) exposed to this concen- tration died at the end of 8 months. The importance of this distinction will be appreciated when the use of application factors is recalled.The use of such factors implies that when a given fraction often set arbitrarily of one tenth or one hundredth for example of the T L with respect to environmental concentrations of a toxin is used little harm will result. As the truly sub-lethal concentrations of most toxins have never been defined such an assump- tion does seem to be presumptuous in most instances. At truly sub-lethal concentrations it is possible that atoxic substance may induce a number of interesting and important effects. (a) inhibition or promotion of growth; ( b ) influence upon reproductive potential i.e. changes in fecundity or brood survival; (c) behavioural changes e.g. the influence of toxicants upon the settling ability of planktonic larvae or responses to environmental factors by larvae and adults (d) an upsetting of the predator - prey relationship; (e) inhibition or other effects in the crustacean moult cycle; (f) effects upon respiration osmo-regulation and ion-regulation ; and (g) accelerated ageing.It must be recognised however that some of these effects e.g. inhibition of growth at an otherwise apparently innocuous concentration may indicate the lethal potential of that concentration. One other effect which cannot be considered with our present limited know- ledge of marine invertebrates has been recognised with respect to vertebrates vix. the induction of disease by sub-lethal concentrations of toxic substances ; even with the verte- brates relatively few such studies have been undertaken.However Friend and Trainer,5 who worked with the mallard Anas platyrhycos showed that after treatment with sub-lethal doses of polychlorinated biphenyls duck challenged with Duck Hepatitis Virus showed the symptoms of the disease more rapidly and also succumbed to it more readily than did the controls. This work is concerned firstly with the means whereby poor ill-acclimated and otherwise unsuitable animals are eliminated from test procedures and secondly with the procedures themselves with the means whereby more meaningful results than those derived by TL tests can be obtained. Throughout the objective has been to bring the study of toxicology in marine invertebrates more nearly in line with the principles and reproducible results expected in chemical analytical techniques.Having said this I am conscious of how much effort is still needed to attain this worthwhile goal. Such effects may include- SELECTION OF TEST ANIMALS- The dependence of workers in the marine invertebrate field upon animals taken from the wild and introduced into the laboratory for the purposes of experimentation have been noted already and the care required at this stage i.e. collection has been discussed by Perkins.l However care in handling during collection is not the sole precaution necessary a t this stage. Commonly juvenile shore crabs Carcinus of approximately 5 mm carapace width maintained in a tank with adequate food will after 6 months range in size from approximately 10 mm to 30 mm carapace width. The shore-dwelling molluscs e g . the winkle Littorina littorea and the dog whelk Thais (Nucella) Zapillus especially the latter will enter states at which growth ceases ; this cessation of growth is protracted and is not apparently related to season.Growth may be resumed eventually but very clearly growth and non-growth forms are in differing physiological states. Although the approach must vary slightly depending upon the species involved experimental animals in general are selected as uniformly as possible according to the criterion that they are about half grown and are growing actively. This does not avoid the problem of inclusion of different ages in the animals selected but it does avoid the problem of Wild stocks of invertebrates do not grow at a uniform rate. 108 ASSESSMENT OF TOXIC EFFECTS UPON MARINE INVERTEBRATES [Proc.Soc. Analyt. Chem. the different responses of actively growing growth-static and senile individuals differing proportions of which must inevitably give rise to poorly reproducible results. For the same reasons malformed or obviously diseased animals are excluded from these collections also. ACCLIMATION OF TEST ANIMALS- Fishes when handled suffer from laboratory diuresis but little is known of this phe- nomenon in the invertebrate field. Nevertheless the process of being caught particularly in a trawl must be a traumatic experience for those invertebrates such as the decapod crustacea which have highly developed nervous systems. A little work performed in this context does suggest that these animals suffer from a condition similar to the laboratory diuresis of fishes. A period of rest or acclimation before experimentation commences is therefore essential.Evidently the process of acclimation undertaken must depend upon the conditions of the subsequent test. With respect to temperature two approaches are valid nix. (1) the temper- atures in the test laboratory are not controlled but are allowed to vary in a manner similar to those in the environment and (2) the temperature of the system is maintained a t some appropriate value. The former approach yields information that is more directly applicable to a particular ecological situation while the latter by suitable choice of temperature can permit one to test the animal at temperatures which if it survives can be taken to ensure in the short term at least that it will survive stresses to which it is likely to be subjected in the field.For the first type of test the animals brought into the laboratory are held for 2 weeks prior to experimental exposure and are fed in this period. $-or the second the animals are held for 1 week at the normal tank room temperature and then transferred to sea water at a temperature of 20 "C for 14 days prior to the experimental exposure; they are fed in this period. In both types of acclimation period a mortality level of up to 10 per cent. is accepted; if mortality exceeds this value then the stock is rejected. CHOICE OF TEST CONDITIONS- The choice of test conditions for aquatic animals must depend to some degree upon the environmental characteristics of the particular situation to which the investigation is related. Nevertheless two principal considerations have to be borne in mind with reference to marine animals in general.Marine animals live in a saline environment that may contain up to 35 g 1-1 of mixed salts in the open ocean and in estuaries any value between this and that of fresh water depending upon the position occupied. In any one situation the salinity may be variable but relatively few animals will experience the whole range from 0 to 35 g l-l and in estuarine areas there is generally a marked reduction in the number of species present with distance moved upstream in a manner related to the ability of the individual species to osmo-regulate or acclimate to a reduced salinity. Nevertheless even where an animal can osmo-regulate over a wide range of salinities care is necessary. For example the mussel MytiZus edzdis when transferred from its normal salinity of 30 g 1-1 in the North Sea to a salinity of 15 g 1-1 in the Bay of Kiel has a respiration rate that differs from the indigenous forms for a period of 4 to 7 weeks which is far in excess of that required for osmotic adjustment.Similarly it has been the custom in some laboratories to use an artificial sea water for toxicity tests but a disturbance in the ionic balance of sea water can have very adverse effects upon its inhabitant^.^^^ For these reasons therefore it is deemed advisable to use natural sea water of a salinity within the range 28 to 32 g 1-1 in tests performed a t Garelochhead. Clearly in those situations where the animal under consideration is adapted to lower salinities this must be allowed for in any experiments undertaken. In those tests which have been performed at a constant temperature the choice of temperature has normally been arbitrary.The oxygen consumption of the limpet Patella increases sharply with increased temperature up to 15 "C and from 20 to 30 "C; however between 15 and 20 "C the increase in oxygen consumption is much less marked.*p9 Similar respiration rate - temperature graphs have been observed in other intertidal invertebrates either whole animals or excised organs.lOJ1 However this type of graph may be evident only at certain times of the year about August in Balanus balanoides and Chthamalus stellatus but quite different respiration rate - temperature graphs may be evident at other times. In the sub-littoral species Balanus balanus there is no evidence of a flattened region of the graph at temperatures between 10 and 15 OC.ll May 19721 ASSESSMENT OF TOXIC EFFECTS UPON MARINE IWERTEBRATES 109 The limpet Patella when transferred to water of a different temperature e.g.from 10 to 20 "C requires a period of 14 days to acclimate to the new t e m p e r a t ~ r e . ~ ~ Similarly the oxygen consumption and filtration rate of the mussel Mytilus edulis become acclimated within 14 days of exposure to a new temperature regime.12 The structure of water is dependent upon temperature and a major transition commences at 15 "C,13 the temperature at which many constant-temperature experiments have been performed. To avoid the difficulties inherent in working at 15 "C a standard temperature of 20 "C has been adopted at Garelochhead. At this temperature the animals are effectively off the respiration-rate plateau the physiological effects of the change of water state at 15 "C (within a small range in the constant-temperature unit) are avoided and the animals are exposed to a temperature that can be experienced in British inshore waters and that is not normally too close to the lethal temperature to produce unreasonable results in the experi- ment.In all experiments continuous gentle aeration is carried out to maintain the oxygen levels near to saturation. As the pH of sea water is dependent upon the carbon dioxide concentration the pH is monitored continuously in selected test vessels; oxygen levels are determined intermittently . The acute toxicity test is normally performed as a 24-h exposure to the toxic solution in a no-flow system followed by a 5-day recovery period.The mortality due to each test solution is defined at the end of this period and the 24-h LC, is determined by graphical interpolation. The duration of the exposure may be extended to 48 or 96 h if the need arises. Because of severe problems in tank hygiene no animals are fed during this period. If any of the controls die the experiment is rejected. PROCEDURE SUBSEQUENT TO TL DETERMINATION- After the TLm with a 5-day recovery period had been determined two different ap- proaches to the problem of toxic effects upon marine invertebrates were adopted; these approaches take advantage of the strength and weakness of our ability to manipulate these animals at the present time. These procedures are (1) studies of the long-term effects of single doses of a toxic substance and (2) the effects of a chronic exposure to very low doses of a toxic substance.Long-term efects of single doses-Although the shore crab Carcinus and the hermit crab Eupagurus can be maintained in the laboratory for a protracted period cannibalism may be a problem in animals that have been treated. This can be overcome by the isolation of individuals in small Tupperware boxes that have been liberally perforated with a $-inch drill. In this instance because a large number of such vessels would be needed per test it is usual to isolate individuals from the control aliquot and those from the highest concentration of test solution in which no mortality occurred during the 5-day recovery period. Field studies of the survival and growth of treated animals can be carried out readily with the winkles L.Zittorea and L. saxatilis the dog whelk Thais (Nucella) ZaPiZZus and the oyster Ostrea. Of these four animals the first two roam freely upon the shore grazing upon algae which include Enteromorpha and epiphytes; Thais (Nucella) also roams freely upon the shore and is a predator of mussels and barnacles in particular. The oyster is a filter feeder that lives on phytoplankton. All four have the peculiar advantage that they inhabit a non-living calcareous shell that is secreted continuously as the animal grows. Because the shell is non- living it can be V-notched without harm to the living tissue and growth subsequent to the notching can be measured easily (Fig. 1). For the winkle growth around the spire is much greater than the concurrent addition in length ; consequently differences in growth are much greater in this direction and yield better results for statistical analysis.Of course the surface is curved but nevertheless by using a thin steel rule permanently held in a form similar to a normal curve the measurements can be made easily.* By using animals tagged with a suitable paint code and V-notched before release to the shore it was possible to show that L. saxatilis treated with B.P. 1002 emulsifier a t doses as low as less than one three-thousandth of the 24-h LC50 died at a greater rate than controls for up to 22 weeks after the treatment had occurred and similar results were obtained for L. littorea and Thais (Nucella) lapillus with respect to oil emulsifier and surfactant alone. Growth was inhibited over a wide range of concentrations when the animals were treated with these substances and occurred at less than one three-thousandth and less than one four-hundredth of the 24-h LC, of L.saxatilis and L. littorea respectively with respect t o B.P. 1002 emulsifier.* 110 ASSESSMENT OF TOXIC EFFECTS UPON MARINE ISVERTEBRATES [Proc. SOC. AnaZyt. Chm. Fig. 1. Growth of a V-notched oyster after treatment for G h with oil emulsifier. It is of interest to note that the response of these animals to an increasing concentration of surfactant is not always to produce an increased mortality or a decrease in growth i.e. it is a paradoxical graph. Although not generally appreciated such responses have been widely reported in a scattered literature with respect to the influence of detergents upon bacteria protozoa algae wheat and mammals and have in consequence received little attention.14 In most instances the cause is unknown or little understood.The concept of the influence of micelle formation does not agree with experimental observations and physicochemical changes related to the formation of liquid crystals of differing structures at different con- centrations may provide a more likely explanation of the phenomenon. Whatever the ex- planation a comparison of three years' work upon surfactants either alone or in detergent formulations with similar work upon mineral acids and salts (excepting those such as alumin- ium which undergoes self-precipitation at higher concentrations) shpwed that the difference in response is significant at the 0.1 per cent. level. Not all substances used in treatment produced inhibition of growth after a single 24-h treatment.The 24-h LC, of L. Zittorea with respect to sodium acetate is greater than 6400 p.p.m. at a salinity of 30 g 1-l; however even at a level of 6400 p.p.m. of sodium acetate no significant inhibition of growth occurred.l On the other hand the 24-h LC, of L. Zittorea with respect to potassium aluminium sulphate is greater than 6400 p.p.m. at a salinity of 30 g 1-l; growth is inhibited at 6400 p.p.m. but not at 800 p.p.m. (i.e. less than one eighth of the 24-h LC,,). The dog whelk Thais (NuceZZa) has a 2411 LC, of 3200 p.p.m. with respect to sodium sulphite at a salinity of 20 g 1-1 but a significant inhibition of growth occurs at 800 p.p.m. (i.e. one quarter of the 24-h LC5,).16 In the field there are some pitfalls in the interpretation of growth data.For example growth may be slowed by the presence of pol- lutants but in a eutrophic situation where many competitors are removed giant forms may result. Turning now to the oyster this animal is treated when it is about 1 inch in diameter. If worthwhile recoveries for growth and mortality studies are to be made it is then too small to be released freely into the environment. In this instance subsequent to treatment the oysters are kept in live boxes suspended from a fleet of buoys at the Faery Isles Loch Sween. The oysters grow well but so do fouling organisms e.g. ascidians which constitute a major nuisance.17 When the oysters have reached a suitable size they are transferred to Linne Mhuirich where they are kept in trays on the sea bed. Clearly the interpretation of such situations requires some care.May 19721 ASSESSMENT OF TOXIC EFFECTS UPON MARINE INVERTEBRATES 111 As with the work with winkles at Garelochhead delayed mortality may occur but although the growth of survivors may be very good growth at sub-TL levels may be inhibited nevertheless. The oyster programme will continue for a further 2 years at which time the oysters should be of a marketable size and large enough to reproduce. By this long-term study it is hoped to investigate the long-term effects if any of a single 24 or 48-h treatment with oil emulsifier upon reproduction palatability and growth. The condition factor i.e. the relative weight of flesh to weight of shell of a lamellibranch mollusc is of great importance to the producer as the price of his produce in the market depends on this factor; commercially acceptable condition factors for mussels are 35 to 40 per cent.Tests performed with Mytilus in the Gareloch suggest that short treatments at high concentrations of oil emulsifier do not have a long-term adverse effect upon condition but the results of the work with oysters are awaited with interest. Long-term chronic exposure studies-Laboratory maintenance of carnivores such as the starfish Asterias rubens the shore crab Carcinus maenas the hermit crab Eupaguvus bernhardus the whelk Buccinum undatum and the dog-whelk Thais (Nucella) lapillus is not difficult as they feed readily upon mussels and success is dependent largely upon good tank hygiene and the prevention of cannibalism. Although these animals will not reproduce in the laboratory they can be maintained in an otherwise healthy condition for a period of several years; consequently death in controls is rare or minimal.They are suitable therefore for use in studies of long-term mortality effects upon chronic conditions and also in predator - prey studies subsequent to acute treatments. In these long-term chronic studies aliquots of animals which depend upon size are maintained in 40 1 of sea water to which an appropriate amount of effluent or toxicant has been added. In general in the marine situation continuous flow exposure is not entirely relevant to the natural situation where the fluctuations due to tide wind and run-out from the land result in an intermittent dosing a t points removed from the immediate vicinity of the effluent source.In consequence therefore the water is changed and the dose renewed in each tank once a week. Such studies have shown that an invertebrate may resist an apparently innocuous sub-lethal concentration for many weeks and then collapse with rapid death of the whole group subjected to the particular treatment. The three following experiments illustrate this statement. A number of marine gastropods have a 24-h LC,, with respect to acetic acid of the order of 6400 p.p.m. The whelk Buccinum subjected to chronic exposures at 100 p.p.m. (i.e. about one sixty-fourth of the TL,) survived well for 12 weeks but all died in the thirteenth week.l5 The hermit crab Eupagurus bernhardus has a 24-h LC, of greater than 6400 p.p.m. with respect to sodium sulphate. Animals subjected to a continuous flow of sea water containing 500 p.p.m.of sodium sulphate (i.e. less than one thirteenth of the TL,) survived well until the twelfth week when 50 per cent. of them died. Studies of the toxicity of a whole effluent with respect to Eupagzwus bernhardus revealed a 24-h LC, of 18 per cent. of effluent in sea water of 30 g 1-1 salinity. Chronic treatment of the hermit crab with concentrations of 10.0 5.0 1.0 and 0.5 per cent. of effluent in sea water of 30 g 1-1 salinity showed that the 10.0 per cent. concentration produced 100 per cent. mortality in 3 weeks the 5.0 per cent. con- centration produced 100 per cent. mortality in 5 weeks but the 1-0 per cent. con- centration produced 8 per cent. cumulative mortality after 7 weeks while after this time no deaths occurred at the 0.5 per cent. concentration.A similar trial with Carcinus maenas required 5 weeks for 100 per cent. mortality at the concentration of 10 per cent. of effluent in sea water and at the lower concentrations no deaths occurred in 7 weeks. This greater resistance of Carciizus compared with Eupagurus is reflected in the field in the distribution of the two species relative to the outfall. In such experiments however it seems that the best expression for mortality is the time to 50 or 100 per cent. mortality a t the given concentration i e . dose-rate graphs for protected periods. No controls died. 1. Collection1 2. Transport1 3. Acclimation 4. TL determination TABLE I PROCEDURES USED IN TOXICITY TESTING WITH MARINE INVERTEBRATES By hand or baited pot; when possible avoid trawl or dredge collections Handle carefully; aerate ( A ) Ambient temperature experimentation.Acclim- ate for 2 weeks a t normal tank room temperatures ( B ) (i) Acclimate for 1 week a t normal tank room tem- perature then- (ii) Acclimate for 2 weeks a t 20 "C Maintain salinity in the range 28 to 32g 1-1. Aerate adeauatelv. Ensure ade- Select-Half grown growing Reject-Mishandled deformed A void-Making coll ectio ns when the air temperature is < 0 "C particularly with those animals taken from below the low-water mark. Similar care will be required a t the other end of the temperature scale but such problems have not arisen a t Garelochhead and uniform1 y sized individ- uals and non-uniform stock A void-Excessive exposure to direct sunlight prolonged exposure to the atmosphere when no shelter is provided and undue disturbance or jarring.Especially avoid overcrowding Do not overcrowd; feed keep clean. Maintain salin- ity in the range 28 to 32 per cent. Aerate adequately. Monitor temperature and pH. Maintain an adequate record of stock Dose period. Do not feed r quaie replication of tests. Monitor temperature pH 1 Recovery period. Do not and oxygen concentration z c Reject-All stocks in which A void-Mixing stock collected the mortality exceeds 10 per on different occasions cent. a t this stage W w 5 E 2 2 $ % ir ? n 0 ? ? b Select-All individuals in normal test aliquots by random number methods. Record-all overt symptoms including number anaesthetised locomotory ability and number patently dead Record-Course of recovery from anaesthesia (if any) mortality and pattern of death ; any other symptoms characteristic of the toxin ' 5.Post-TL,, studies ( A ) Long-term recovery from single treatments Laboratory studies. Main- tain salinity in the range 28 to 3 2 g 1-l. Aerate ad- equately. Monitor temper- ature pH and oxygen con- centration Field studies Select a givcn group of treated animals normally those from the highest concentration a t which 100 per cent. had survived to the end of the 5-day recovery period. Feed. This method is suitable for carnivores e.g. Carcinus (shore crab) and Eupa- gurus (hermit crab). When cannibalism occurs compare survival in treated animals and controls maintained in groups and in solitary confinement. Study-Food intake growth and mortality (a) Release large aliquots including controls (more than 100 individuals per concentration) into the environment after suitable marking.Study-Growth mortality and vulner- ability to predation. Suitable for herbivores such as Littorina and carnivores such as Thais (Nucella) (b) When method (a) is unsuitable because the test animal is either too vulnerable on grounds of size or re-capture is likely to be a problem treated animals and controls can be cultured in live boxes suspended from a trot line. Subse- quently larger individuals can be cultured by normal methods. Suitable for Buccinum (whelk) (not re-captured easily) ; Ostrea (oyster) and Chlamys (queen scallop) (too vulnerable a t a small size). Study-Growth mortality reproductive status and taste ( B ) Long-term chronic studies. Maintain salinity in the range 28 to 32 g 1 - I . Aerate adequately. Monitor temperature pH and oxy- gen concentration Expose small numbers ( 5 to 8) of test animals to 40-1 volumes of toxin solution a t concentrations that are low or very low compared with the TL,.Study-Feeding growth development of mortality and any other parameter pertinent to the particular animal and toxin. Feed test stock and controls on the day prior to the renewal of the test dose. A t the time of the renewal wash the tanks thoroughly with fresh water; scrub when necessary. Scrupulous attention to tank hygiene is essential. Stock must be collected handled and acclimated according to the criteria 1 to 3 above. Death in controls should be regarded as undesirable. Strong justification is necessary for the continuation of an experiment once control death develops ; such justification may include cannibalism a t the time of ecdysis but must be used with care 114 ASSESSMENT OF TOXIC EFFECTS UPON MARINE INVERTEBRATES [Proc.SOC. Analyt. Chem. In such protracted experiments it seems possible that a persistent disturbance of the ionic balance in sea water is responsible for the observed mortality. Furthermore some evi- dence comes from experimental work on Carcinus maenas. When whole crabs are immersed in sea water containing enough acetic acid or potassium aluminium sulphate to reduce the pH to 4.0 and the blood is extracted periodically then the pH of the crab’s blood is depressed rapidly in the first hour and more slowly for the remaining 5 h of the experirnent.l6+ From work on the trophic ecology of Carcinus it is possible in the field to recognise the shells of L.saxatilis that have been subject to predation by Carcinus.19 When L. saxatilis treated with concentrations ranging from 0.1 to 3000 p.p.m. (24-h LC, > 3000 p.p.m.) of B.P. 1002 emulsifier for 24 h were released on the shore treated animals at allconcentrations were taken in preference to the controls by C a r c i n ~ s . ~ Unfortunately such work cannot easily be repeated in the laboratory. However the dog whelk Thais (Nucella) treated at 50 and 500 p.p.m. of detergent for 24 h (24-h LC, > 5000 p.p.m.) at 11 “C and allowed to recover f ( I ) days were placed in tanks with equal numbers of untreated Thais (Nucella) and sub- j The whelk consumed three times as many tr,,,cd Thais (Nucella) as untreated animals. The results of such experiments are not always so clear-cut however for in a series of selection experiments performed by using the oyster Ostrea as prey and with Eupagurus and Carcirtus as predators the controls rather than the treated animals were selected preferentially suggesting that in this instance at least the oyster was more palatable to these animals before rather than after treatment( Gribbon E.private communication). A summary of the procedures used in toxicity testing with marine invertebrates is given in Table I. 1 to predation by the whelk Buccinuum. CONCLUSIONS Although there are difficulties that have to be overcome if marine invertebrates are to be used in studies of toxicology it is not unreasonable when working with these organisms to aim for the standards achieved by chemical analysts. By paying systematic attention to the problems that arise when collecting handling acclimating and working with such stock it is possible to eliminate inadequate techniques and to improve the reproducibility of the results obtained.As the objective of such work is a rational understanding of the influence of toxic substances and the prevention of pollution of the marine environment a change in emphasis to long-term studies and away from the short-term TL studies is both necessary and more attainable if the precautions proposed are adopted. Clearly such precautions as have been stipulated apply to and are most relevant to the animals discussed in this paper vix. Eupagurus bernhardus Carcinus maenas Littorina littorea L. saxatilis Thais (Nucella) lapillus Buccinum undatum Mytilus edulis Ostrea edulis and Asterias rubens but the general concept is applicable to all marine animals.Equally clearly such methods as have been described do not represent an end but rather a beginning and improvements in techniques must follow if the standards evidently necessary are to be achieved. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. REFERENCES Perkins E. J. Mar. Pollut. Bull. 1972 3 No. 1 13. Mawdesley-Thomas L. New Scient. 1971 49 No. 734 45. Wilson D. P. J . Mar. Biol. Ass. U.K. 1968 48 177. Perkins E. J. Chem. & Ind. 1970 14. Friend M. and Trainer D. O. Science N.Y. 1970 170 1314. Smith R. Mar. Biol. Biol. Colloquium 1959 59. Lange R. Nytt Mag. Zool. 1968 16 No. 1 1. Davies P. Spencer J . Mar. Biol. Ass. U.K. 1966 46 647. - Proc. Challenger SOL 1971 4 No. 3. Percy J . A. and Aldrich F. A. Nature Lond. 1971 231 393. Newell €3. C. “Biology of Intertidal Animals,” Logos Press London 1970. Widdows J. and Bayne B. L. J . Mar. Biol. A s s . U.K. 1971 51 827. Erlander S. R. Sci. J . 1969 5A No. 5 60. Schatz A. Schalscha E. B. and Schatz V. Compost Sci. 1964 Spring 26. Gribbon E. Final Honours Thesis University of Strathclyde 1969. Robinson D. J. S. Final Honours Thesis University of Strathclyde 1968. Perkins E. J. and Gribbon E. Mar. Pollut. Bull. 1972 in the press. Parker J . Final Honours Thesis University of Strathclyde 1971. Perkins E. J. and Penfound J. M. Spectrum BY. Sci. News 1971 No. 84(7).

ISSN:0037-9697    

DOI:10.1039/SA9720900105

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

May 19721 GEOLOGICAL APPLICATIONS OF PARTICLE SIZE ANALYSIS 115 Geological Applications of Particle Size Analysis The following is a summary of the paper presented a t a Meeting of the Particle Size Analysis Group held on November 23rd 1971 and reported in the February issue of Proceedings (p. 28). The Significance and Limitations of Statistical Parameters for Recognising Sedimentary Environments BY J. R. HAILS (hTatatval Eizuivonnaent Research Council U n i t of Coastal Sedi!mentation Beadon Road Taunton Somerset) IN the space available it is difficult to cover adequately the entire spectrum of such a highly interesting and yet controversial subject as grain-size distributions and depositional environ- ments. Inevitably because of the extensive literature one is necessarily compelled to be selective by referring to the more important standard references and to the evidence that has come to light during personal research.The mechanical analysis of sand- and gravel-sized particles by sieving is a conventional and widely used technique even if many sedimentologists argue that the behaviour of sedimen- tary particles during transportation and deposition is more closely represented by their settling velocities. Many workers still claim that the accuracy of the settling tube method is restrictive although it is a quicker way of examining particles. Since Udden’s pioneer and classic work on the grain size of wind-blown deposits just before the turn of the century sedimentary petrographers have held divergent views about the usefulness of size-frequency analyses to determine sedimentary environments and the transport history of sediments.Despite several notable contributions to the understanding of grain-size distributions during the past two decades relatively few researchers have attemp- ted to study the relationship between depositional processes and grain-size distributions. The main purpose of this paper is to review the graphical and statistical techniques that are most widely used for obtaining grain-size data to examine both the significance and limitations of these data for distinguishing ancient and modern sedimentary environments and to consider some of the problems that need to be resolved if statistical parameters are to be universally accepted as reliable criteria from which to draw conclusions about geological processes past and present.GRAPHICAL AWD MOMENT MEASURES- Any assessment of the relative significance of graphical and moment measures for distin- guishing ancient and modern sedimentary environments must take cognisance in particular of the lack of standard sampling procedures used in the field the different analytical techniques used in the laboratory and of course experimental errors. Most statistical work is undertaken with cumulative curves which should always be drawn on percentage probability graph paper. This makes normal curves plot out as straight lines. Of course grain-size parameters can be made directly from the data by computer or by hand without drawing a cumulative curve. Many graphical measures of average grain size and several descriptive scales for sorting have been proposed hitherto.These have been succinctly reviewed by Folk,l who also evaluated the significance of skewness (or asymmetry) and kurtosis (or peakedness) two parameters that are widely used to measure the non-normality of a distribution. Folk and Ward2 developed graphical versions of statistical measures that have been adopted subse- quently by many sedimentologists. As Folk stated,l few quantitative data can be read from graphical methods. These are summarised as follows- Mean size ( M J - * . (1) . . .. . . $16 + $50 + $84* 3 M = * The phi scale is a log transformation to simplify the arithmetic involved in computing statistical parameters with transformation from negative to positive a t 1 mm. 116 GEOLOGICAL APPLICATIONS OF PARTICLE SIZE ANALYSIS [Proc. SOC. Analyt. Chem. Inclusive graphical standard deviation (q)- .. - - (2) .. 484 - $16 495 - 45 4 -k 6.6 a = Skewness (SKI)- .. . - (3) .. . . - - (4) $16 + 484 - 2450 45 + 495 - 2450 2(#84 - $16) -‘r 2($95 - 45) ” SKI = Kurtosis (KG)- .. 495 - 45 2*44(476 - 425) KG = Friedman3 has also summarised several distinct statistical methods that have been proposed for interpreting depositional environments from grain-size data. He used the first to fourth moments of a grain-size distribution to distinguish between dune beach and river ~ a n d s . ~ Equations for the calculation of these statistical parameters are- Mean (Xd) first moment- . . . . * * (5) 04 = [Cf(m+ - X4)2/100]4 . . .. . . * - (6) . . . . - * (7) a44 = (1/100)~4-42f(m$ - X+)4 . . .. .. - * (8) Xd = 1/100Cfm . . where f is a grade-size frequency and m4 is the mid-point of each grade-size in phi units.Standard deviation (qb) second moment- Skewness (or34) third moment- Kurtosis (or44) fourth moment- a34 = (1/100)~4-3~f(~.~;6 - X4)3 .. The method of moments is undoubtedly the best way of obtaining parameters of a frequency distribution as the entire frequency distribution is used in the determination instead of a few selected percentiles. It is pertinent to mention here that faulty sieves can affect the third and fourth moments (skewness and kurtosis) two particularly sensitive parameters. Also because the method includes the entire distribution it is necessary to make some arbitrary assumption about the grain size of the “fines” before a computation is made if the fine-grain fraction (silt and clay) is not analysed. Spencer5 demonstrated that the majority of grain-size frequency curves are actually mixtures of one or more log-normally distributed sediment populations and that mixing of these populations may be indicative of depositional processes.GRAIN SIZE DISTRIBUTIONS AND DEPOSITIONAL PROCESSES- VisherG has summarised the work of sedimentologists who have made notable contributions to an understanding of the relationship between grain-size distributions and the depositional processes responsible for their formation. Inman7 recognised that surface creep saltation and suspension are the three fundamental modes of transport of sedimentary particles. Sindowski* empirically classified size-distribution curves according to seven different deposi- tional types namely relict strand tidal flat shelf tidal inlet minor tidal channel and fluvial.He studied the relation of sediment textures from known depositional environments to the shapes of grain-size curves but did not relate these shapes to the transport and depositional processes that formed them. J ! I o s s ~ ~ ~ O used the shapes and sizes of grains to identify sub-populations produced by the three means of sediment transport described by Inman7 and Bagnold,ll and discovered that these three populations could be intermixed in the same sample. Visher6 analysed samples collected along profiles across the strandline from the frontal dune to several hundred metres offshore at more than thirty localities from Grand Isle Louisiana to Cape Hatteras North Carolina U.S.A. Analysis of the size data obtained from these samples showed that there were several different fundamental shapes of the log-probabi- lity curves and that the samples could be classified into those deposited by beach processes I t is generally accepted that sediments follow a log-normal distribution.May 19721 GEOLOGICAL APPLICATIONS OF PARTICLE SIZE ANALYSIS 117 (swash and backwash action on the beach face) aeolian processes wave action and breaking waves in the nearshore zone. Each of these four shows characteristic log-probability plots. From the available evidence there seems little reason to doubt that the analysis of log- probability grain-size distribution curves appears to be a fruitful method for studying sedi- mentary dynamics. Folk and Ward,2 Mason and Folk12 and Friedman4 demonstrated that grain-size para- meters are useful criteria for distinguishing between beach dune and river sands.Friedman found that the distribution curves of river sands such as those of dune sands are generally positively skewed and within limitations medium to fine-grained and very fine-grained sands can be distinguished from beach sands on the basis of plots of third moment (skewness) against standard deviation (sorting). The third moment (skewness) of coarse- grained sand is inconclusive however as an indicator of depositional environments. Dune sands are generally better sorted than river sands even if the transportation of these sands represents for the most part unidirectional flow. On beaches fine-grained particles of sand are removed by winnowing. The distribution graph of a winnowed sand lacks a fine-grained end in comparison with a normal curve thus indicating negative skewness.The degree of sorting of beach sands is related not only to the selective action of wind in removing the “fines” from the beach face but also to the origin of the sand. Along many sectors of the New South Wales Coast where the author has studied the textural properties of Pleistocene and Holocene barrier sands there is very little difference between the sorting values of beach and dune sands regardless of their age. As these sands must have been re-worked on several occasions in the geological past they can best be described as polygeizetic because their origin is complex in relation to time process and place. In fact under these conditions skewness is the only environmentally sensitive parameter that can distinguish between beach barrier and dune sands.13 Although several studies have been made of inland desert dunes relatively little syste- matic statistical work has been completed.However Folki4 recently evaluated the relation- ship of mean size sorting and higher moment measures with the micro-geomorphology of longitudinal dunes on the edge of the Simpson Desert N. T. Australia. He discovered that dune crests are coarsest and best sorted because they are composed of the most easily saltated fine sand (about 2.5#); windward and leeward flanks and reg (residual material left after wind activity which consists of poorly sorted polymodal material) are progressively fine and also show regular changes in higher order grain-size parameters. DIAGENESIS- While most recent beach and off shore marine sands are negatively skewed Friedman15 discovered that most of the ancient sands he studied from cores and outcrops were positively skewed.He therefore suggested that a shift in skewness characteristics was an important function of diagenetic alteration (development of secondary overgrowths solution and the post-depositional introduction of interstitial material). ChappelP studied poorly lithified Pleistocene beach sands cemented in varying degrees by limonite along the west coast of New Zealand. Skewness measurements showed that there was an apparent shift of the beach sand values into the area of positive skewness which was increasingly pronounced in older sands. Chappell concluded that the limonitisation of poorly lithified sandstones tended to obscure the negative skewness of fossil beach sands.He added that positive skewness could not be taken to indicate aeolian sands unless negative skewness occurred in adjacent (probable beach sand) sediments. Also alteration of the sand by ground water action offshore palaeo-winds and mixed populations often obliterated negative skewness. Similarly it has been found from studies of deeply podzolised Pleistocene barrier sands in New South Wales and on the Georgia Coastal Plain U.S.A. that both diagenetic and pedo- genetic processes are possible causes of positive skewness.13~17 Visher6 concluded that the determination of the depositional environments of an ancient sand is a difficult problem and in most instances physical biological and chemical criteria are needed before a definite interpretation is possible. Most ancient sandstones are generally of marine origin.118 AUGER SPECTROSCOPY [Proc. SOC. Amlyt. Chem. CONCLUSIONS- This brief paper has summarised some of the most rewarding lines of research that have been undertaken during the past two decades or so. Nevertheless there are a number of aspects that require further clarification and study. These range from the improvement of laboratory and sampling techniques to the statistical manipulation of the data obtained. In particular more work needs to be undertaken in order to try to explain the apparent sensitivity of higher moment measures to sedimentary environments and the relationship of present-day sediments to their ancient analogues. 1. 2. 3. 4. 5. 6. 5 . 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. REFEREXCES Folk R. L. Sedimedology 1966 6 73. Folk R. L. and JTJard W. C. J . Sedinz. Petrol. 1957 27 3. Friedman G. M. Ibid. 1967 37 327. - Ibid. 1961 31 514. Spencer D. W. Ibid. 1963 33 180. Visher G. S. Ibid. 1969 39 1074. Inman D. L. Ibid. 1949 19 51. Sindowski I<. H. Geol. Jb. 1958 73 235. Moss A. J. Amer. J . Sci. 1962 260 337. __ Ibid. 1963 261 297. Bagnold R. A. Phil. T r a n s . Roy. SOC. 1956 249 235. Mason C. C. and Folk R. L. J . Sedinz. Petrol. 1958 28 211. Hails J. R. Ibid. 1967 37 1059. Folk R. L. Sedimentology 1971 16 5. Friedman G. M. J . Geol. 1962 70 737. Chappell J, J. Sedim. Petvol. 1967 37 157. Hails J. R. and Hoyt J. H. Ibid. 1969 39 559.

ISSN:0037-9697    

DOI:10.1039/SA9720900115

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

118 AUGER SPECTROSCOPY [Proc. Soc. Amlyt. Chem. Auger Spectroscopy The following is a summary of the paper presented at a meeting of the Midlands Region on January 27th and reported in the April issue of Proceedings (p. 77). Analytical Aspects of Auger Spectroscopy BY M. THOMPSON (Deflartment of Chemistry University of Technology Loughborough Leicestershire LE11 3T U ) . ELECTRON spectroscopy can be defined as the study of electrons emitted when matter is irradiated with photons or partic1es.l These electrons are analysed according to their kinetic energy and counted the resulting graph of count-rate veysus energy being known as the electron energy spectrum. The technique encompasses several closely related but distinct branches ; these are vacuum ultraviolet photoelectron spectroscopy,2 X-ray photoelectron spectroscopy commonly referred to as ESCA,3 Penning ionisation spectroscopy,4 ion neutral- isation spectro~copy,~ electron impact energy loss spectroscopy,6 ionisation spectroscopy' and Auger spectroscopy.* In Auger spectroscopy electrons are ejected from a sample solid or gas in a secondary step after initial bombardment with electrons or X-ray photons (such electrons are therefore observed in a standard ESCA spectrometer).The secondary electrons are then passed into an electron energy analyser. Two types of analyser are in common use both functioning on electrostatic principles. These are the retarding field LEED-Auger device and dispersive field cylindrical mirror analy~er.~ Discussion of the Auger process in more detail is necessary to describe the information that can be obtained by this technique.The process follows the ejection of a primary electron from an inner-core level W after bombardment with electrons or X-rays. The resulting hole is filled by an electron dropping from a less tightly bound level X. The energy released in this transition can eject another electron (the Augerlo electron) from a level Y or appear as X-ray fluorescence. The emission of Auger electrons relative to X-ray fluorescence depends May 19721 AUGER SPECTROSCOPY 119 essentially on the energy of level W. For the lighter elements X-ray production can become negligible (energy of level W less than 500 eV) . The energy of the Auger electron is characteristic of the atom from which it comes as is the case with the primary photoelectron in ESCA. However unlike in the latter technique the Auger electron is independent of the source energy.There are several Auger processes for most elements usually described in X-ray notation i.e. W X Y = K L M etc. and observation of these transitions allows elemental analysis of gaseous samples and of the surface of solids to be achieved. The use of Auger spectroscopy as a sensitive surface probe originates from the fact that results are derived from the top five (approximately) atom layers depending on the substance and primary beam energy. The concentrations of surface species are usually described in terms of atoms per square centimetre (1 monolayer m 8 x 1014 atoms cm-2) and in principle 1O1O atoms cm-2 should be detectable. However it has been emphasised that the use of such two-dimensional nomenclature can be mi~leading.~ More correctly the surface should be described in terms of the volume of surface analysed under given experimental conditions.Unfortunately the detected volume depends on two parameters that are difficult to define wiz. the distribution of elements within the volume and the escape depth of ejected electrons. As this implies calibration of surface concentrations is difficult although these have been possible in certain instances. When a primary beam of electrons impinges on the sample (1000 to 1500 eV in energy) the Auger peaks in the spectrum of electrons leaving the surface represent only a fraction of the total number of electrons being analysed. The distribution of electrons consists of those from the incident beam elastically scattered from the surface (a sharp peak at the incident energy) those from a cascade of "true" secondary electrons beginning at about 150 eV with a peak a t approximately 5 eV and small Auger and energy loss peaks superimposed on the back- ground.It is accepted practice to make the Auger peaks more conspicuous by differentiating the spectrum. Brundlell has suggested that the use of X-ray impact for the Auger study of surfaces should be considered more seriously as an alternative to electron impact as X-ray induced spectra have the distinct advantage that background due to scattered electrons is much reduced when there is no primary electron beam. However a comparative study of both sources used to form the inner-core level hole is required to examine the relative probe depths of X-ray and electron beams.Owing to the nature of the technique Auger spectroscopy can be routinely used to detect elements present at a surface. Therefore there are many applications in the area of thin- film technology. For example surface-etching procedures can be evaluated and grain- boundary segregations surface-catalysis effects and metal-surface oxidation can be studied. An interesting example of an etching study is that due to Chang,12 who obtained the Auger spectra of clean and iodine-etched silicon surfaces. Carbon and oxygen were found to be the major surface contaminants. The concentrations of these elements were determined by comparison with Auger signals from known surfaces. Heating to 1250 "C for 15 minutes was sufficient to lower considerably the contamination by carbon and oxygen. However heat treatments above 1000 "C were accompanied by the appearance of metallic impurities such as chromium manganese and iron at the silicon surface.In addition to its application in the elemental mapping of surfaces Auger spectroscopy can be used to study the environment of an element at a surface. Two types of information are conveyed by this technique viz. chemical shift effects in the core levels due to changes in valence shell electrons (WXY transitions where WXY are inner levels) and Auger transitions that directly reflect changes in valence electrons (WXV or WVV transitions where V repre- sents a valence-band level). An example is the study of carbide formation and carbon monoxide adsorption at a molybdenum (1 10) surface via carbon valence-shell spectra.13 .!41so Haas and Grant14 examined the oxidation of a tantalum (110) surface by comparing the oxide structure at the surface found by LEED methods with chemical shifts of a tantalum Auger transition.The shifts corresponded to increases of binding energy with increasing oxidation of the surface of the metal. Gas-phase Auger spectra exhibit many discrete transitions that involve all valence-shell molecular orbitals instead of the broad valence-band peak of a solid. Also vibrational structure may be present. Both carbon monoxide and carbon dioxide have many peaks between 220 and 270 eV and between 460 and 510 eV that are characteristic of carbon and 120 CARBON IN EFFLUENTS [Proc. SOC. Analyt. Chem. oxygen respectively. However the detailed structures in these regions are characteristic of the individual molecule^^^; therefore the spectra give both elemental and molecular infor- mation.1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. REFERENCES Baker A. D. Brundle C. R. and Thompson M. Chem. SOC. Rev. in the press. Turner D. W. Baker A. D. Baker C. and Brundle C. R. “Molecular Photoelcctron Spectro- scopy,” John Wiley London 1970. Siegbahn K. Nordling C. Johansson J. Hedman J. Heddn P. F. Hamrin K. Gelius U. Bergmark T. \Verne L. O. Manne R. and Baer Y. “ESCA Applied to Free Molecules,” North-Holland Publishing Co. Amsterdam 1969. CermAk V. Colln Czech. Chem. Conzm. 1968 33 2739. Hagstrum H. D. Phys. Rev. 1966 150 495. Berry R. S. Ann. Rev. Phys. Chenz. 1969 20 357. Gerlach R. L. Houston J. E. and Park R. L. Appl. Phys. Lett. 1970 16 179. Harris L. A. Analyt. Chem.. 1968 40 No. 14 24,4. Chang C. C. Surface Sci. 1971 25 53. Auger P. J . Phys. Radium 1925 6 205. Brundle C . R. Surface Sci. 1971 27 681. Chang C C. Ibid. 1970 23 283. Haas T. W. and Grant J. T. A$@. Phys. Lett. 1970 16 172. ~ ~- Phys. Lett. A 1969 30 272. Moddeman W. E. Carlson T. A. Krause M. O. and Pullen B. P. J . Chem. Phys. in the press.

ISSN:0037-9697    

DOI:10.1039/SA9720900118

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

120 CARBON I N EFFLUENTS [Proc. SOC. Analyt. Chem. Carbon in Effluents The following is a summary of one of the papers presented at a Meeting of the Midlands Region held on March 16th 1972 and reported in the April issue of Proceedings (p. 77). Carbon in Effluents BY H. A. C. MONTGOMERY (Water Polltdion Research Laboratory of the Department of the Environment E‘lder W a y Stevenage Hertfordshire SG 1 1 T H ) THE determination of the concentration of organic carbon in effluents and receiving waters is useful both for measuring pollution and for evaluating the performance of treatment processes especially when a mass balance is required. Because the carbon atom seems to lack analytically useful properties organic carbon must be converted to some easily measurable compound such as carbon dioxide or methane.The traditional method,l in which the carbon dioxide formed by heating the sample with chromic acid is determined by absorption in barium hydroxide solution and back- titration is unpleasant to use and rather insensitive. A sensitive but tedious method developed about 10 years ago involves the high- temperature combustion of a relatively large sample and determination of the resulting carbon dioxide by non-dispersive infrared analysis2 A variation of this method which is particularly suitable for sea water is to carry out the combustion in sealed tubes with persulphate as the oxidising agent3; it is also possible to use dissolved oxygen as the oxidant if the sample is subjected to intense ultraviolet radiation at short wavelength^.^ Another variation used in a commercially available instrument involves the injection of a small sample into a furnace and passage of the carbon dioxide through a highly sensitive infrared analy~er.~ A method with potential for use in water-quality monitoring is to make use of empirical relationships between the concentration of organic carbon and the ultraviolet absorbance.‘j Some earlier7 and more recent work on the identification of the organic constituents of sewage and biologically treated sewage effluents was mentioned.REFERENCES 1. Ministry of Housing and Local Government “Methods of Chemical Analysis as Applied to Sewage and Sewage Effluents,” H.M. Stationery Office London 1956. May 19721 PUBLICATIONS RECEl VED 121 2. 3. 4. 5 . 6. 7. Montgomery H. A. C . and Thorn N. S. Analyst 1962 87 689. Menzel D. W. and Vaccaro R. F. Limnol. Oceanogr. 1964 9 138. Erdhardt M. Deep-sea Res. 1969 16 393. Van Hall C. E. Safranko J. and Stenger V. A. Analyt. Chem. 1963 35 315. Ministry of Technology “Water Pollution Research 1967,” p. 196 and subsequent issues H.M. Painter H. A. in Ciaccio L. L. Editor “Water and Water Pollution Handbook,” Volume I Stationery Office London. Marcel Dekker New York 1971 Chapter 7.

ISSN:0037-9697    

DOI:10.1039/SA9720900120

出版商:RSC    

年代:1972

数据来源: RSC

摘要:

May 19721 PUBLICATIONS RECEl VED 121 Publications Received The publications listed below have been received by the Editor of The Analyst in which journal Book Reviews will continue to appear. COORDINATION CHEMISTRY. Volume 1. Edited by ARTHUR E. MARTELL. A .C.S. Monograph No. 165. Pp. xxiv + 577. New York Cincinnati Toronto London and Mclbourne Van Nostrand Reinhold Co. 1971. Price f[l6.25. TREATISE ON ANALYTICAL CHEMISTRY. Part I. THEORY AND PRACTICE. Volume 9. Edited by I. M. KOLTHOFF and PHILIP J. ELVING. Pp. xvi + 5385-5937. New Yorli London Sydney and Toronto Wiley-Interscience. I97 1. Price 12. QUANTITATIVE CHEMISTRY. By MARGARET LOWE BENSTON and MOIRA K. JAATTEENMAKI. Pp. xiv + 242. New York Cincinnati Toronto London and Melbourne Van Nostrand Reinhold Co. 1972. Price j56.95. 122 SHORT COURSES [Proc.SOC. Analyt. Chem. AIR AND WATER POLLUTION. Proceedings of the Summer Workshop August 3 to August 15 1970 University of Colorado. Edited by WESLEY E. BRITTIN RONALD WEST and ROBERT WILLIAMS. Pp. xviii + 613. London Adam Hilger. 1972. Price LS. SELECTED PRINCIPLES OF ORGANICHEMISTRY. By BENJAMIN F. PLUMMER. Pp. xii + 308. New York Cincinnati Toronto London and Melbourne Van h'ostrand Reinhold Co. 1972. Price 44-50. Proceedings of the International Solvent Extraction Conference ISEC 7 1 The Hague 19-23 April 1971. Edited by J. G. GREGORY B. EVANS and P. C. WESTON. Volume 1. Pp. xvi + 819. Volume 11. Pp. xvii-xlviii + 820-1461 + D1-DlOG. London Society of Chemical Industry. 1971. Price j525. MOSSBAUER EFFECT DATA INDEX COVERING THE 1970 LITERATURE. Edited by JOHN G.STEVENS and VIRGINIA E. STEVENS. Pp. x + 369. London Adam Hilger. 1972. Price 412.60. By TIBOR TOROK and KAROLY ZIMMER. London New York and Rheine Heyden and Son Ltd. 1972. Price L3.50; $9; DM32. Edited by SIDNEY SIGGIA. Pp. xii + 428. New Yorlr London Sydney and Toronto Wiley-Interscience. 1972. Price 47-85 GAS ANALYSIS BY GAS CHROMATOGRAPHY. By P. G. JEFFERY and P. J. KIPPING. Second Edition. Pp. x + 196. Oxford New York Toronto Sydney and Braunschweig Pergamon Press. 1972. Price L5.50. SOLVENT EXTRACTION. QUANTITATIVE EVALUATION OF SPECTROGRAMS BY MEANS OF l-TRANSFORMATION. Pp. viii + 40 40-114 loose leaf. INSTRUMENTAL METHODS OF ORGANIC FUNCTIONAL GROUP ANALYSIS. International Series of Monographs in Analytical Claemistry. Volume 17. Short Courses of Interest to Analytical Chemists Available at Universities Colleges of Technology and Polytechnics in the U.K. FIFTH LIST* SUBJECT DATES PLACE$ CONTACT Full -time cowses t - Activation Analysis June 5-7 1972 U. Research Reactor Dr. G. R. Gilmore Universities Research Reactor Risley Warrington Lancashire. Recent Trends in September 14 Manchester P. Mr. G. B. Stoker Dept. of Food Analysis 1972 Chemistry and Biology John Dalton Faculty of Technology Manchester Polytechnic Chester St. Manchester M1 5GD. for further information * The fourth list appeared in the March 1972 issue of Pvoceedings p. 74. t These are all-day courses lasting one or more days. $ Abbreviations C.T. = College of Technology; P. = Polytechnic; U. = University; U.T. = University of Technology.

ISSN:0037-9697    

DOI:10.1039/SA972090121b

出版商:RSC    

年代:1972

数据来源: RSC