Sample Preparation for Trace Element Analysis, Volume 41 0444511016

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Because of rapid advances in the medical sciences, in particular, independent verication of diagnoses anddrug dosages should be made.First edition 2003Library of Congress Cataloging in Publication Data/ edited by Zoltan Mester and Ralph Sturgeonp. cm. -- (Comprehensive analytical chemistry ; v. 41)Includes bibliographical references and index.ISBN 0-444-51101-6 (pbk. : alk. paper) -- ISBN 0-444-51101-6 (hardbound : alk. paper)1. xxxx 2. xxxx 3. xxxx I. Mester, Zoltan and Sturgeon, RalphII. Series.QD75. W75 v. 41[QD75.4.S24]543/.02--dc21 2002072248British Library Cataloguing in Publication DataA catalogue record from the British Library has been applied for.ISBN: 0-444-51101-6ISSN: 0166-526X* The paper used in this publication meets the requirements of ANSI/NISO Z39.48-1992 (Permanence of Paper).Printed in The Netherlands.COMPREHENSIVE ANALYTICAL CHEMISTRYADVISORY BOARDProfessor A.M. BondMonash University, Clayton, Victoria, AustraliaDr T.W. ColletteUS Environmental Protection Agency, Athens, GA, U.S.A.Professor M. GrasserbauerDirector of the Environment Institute, European CommissionJoint Research Centre, Ispra, ItalyProfessor M.-C. HennionEcole Superieure de Physique et de Chimie Industrielles, Paris,FranceProfessor G. M. HieftjeIndiana University, Bloomington, IN, U.S.A.Professor G. Marko-VargaAstraZeneca, Lund, SwedenProfessor D.L. MassartVrije Universiteit, Brussels, BelgiumProfessor M.E. MeyerhoffUniversity of Michigan, Ann Arbor, MI, U.S.A.Wilson & WilsonsCOMPREHENSIVE ANALYTICAL CHEMISTRYEdited byD. BARCELOResearch ProfessorDepartment of Environmental ChemistryIIQAB-CSICJordi Girona 18-2608034 BarcelonaSpainWilson & WilsonsCOMPREHENSIVE ANALYTICAL CHEMISTRYVOLUME XLISAMPLE PREPARATION FOR TRACE ELEMENTANALYSISEdited byZ. MESTERR. STURGEONInstitute for National Measurement StandardsNational Research Council1500, Montreal RdOttawa, ON, KIA 0R6,Canada2003ELSEVIERAMSTERDAM BOSTON HEIDELBERG LONDON NEW YORK OXFORD PARIS SAN DIEGOSAN FRANCISCO SINGAPORE SYDNEY TOKYOCONTRIBUTORS TO VOLUME XLIFreddy C. AdamsDepartment of Chemistry, University of Antwerpen,Universiteitsplein 1, B-2610 Antwerpen, [email protected] AlzagaEnvironmental Chemistry Department, IIQAB-CID-CSIC, JordiGirona, 18, E-08034 Barcelona, Spain.Scott AndersonAir Liquide Balazs Analytical Services, 46409 Landing Pky,Frement, CA 94538, USA.Kevin AshleyU.S. Department of Health and Human Services, Centers forDisease Control and Prevention, National Institute forOccupational Safety and Health, 4676 Columbia Parkway,Mailstop R-7, Cincinnati, OH 45226-1998, [email protected] P. BaldwinAmes Laboratory, Iowa State University, Ames, IA 50011,USADavid BarclayCEM Corporation, 3100 Smith Farm Road,P.O. Box 200, Matthews, North Carolina 28106-0200, [email protected] R. BarefootDepartment of Geology, Earth Sciences Centre, 22 Russell Street,Toronto, Ontario, M5S 3B1, Canada.Douglas C. BaxterDivision of Chemistry, Lulea University of Technology, SE-971 87Lulea , Sweden. [email protected] M. BayonaEnvironmental Chemistry Department, IIQAB-CID-CSIC,Jordi Girona, 18, E-08034 Barcelona, [email protected] BettiEuropean Commission, JRC-ITU, P.O. Box 2340, 76125 Karlsruhe,GermanyviRobert I. BottoAnalytical Services Laboratory, Baytown Chemical PlantLaboratory, 4500 Bayway Dr. Baytown, TX 77520, [email protected] BouyssiereCNRS UMR 5034 Helioparc 2, av. Pr. Angot F-64053 PAU,France.Yong CaiDepartment of Chemistry and Southeast Environmental ResearchCenter, Florida International University, Miami, Florida 33199,USA. [email protected] CamaraDepartamento de Quimica Analitica Facultad de Ciencias Quimicas,Universidad Complutense de Madrid 28040 Madrid, [email protected] CamelInstitut National Agronomique Paris-Grignon, Laboratoire deChimie Analytique, 16 rue Claude Bernard, 75231 Paris Cedex 05,France. [email protected] A. CarusoDepartment of Chemistry, University of Cincinnati,P.O. Box 210172, Cincinnati, OH 45221-0172, [email protected] Dolores Luque de CastroDepartment of Analytical Chemistry Annex C-3, Campus ofRabanales, University of Cordoba, E-14071 Cordoba (Spain)[email protected]. [email protected] Claisse2780 Bd de Monaco, Quebec QC, Canada [email protected] ClementMinistry of the Environment, 125 Resources Road, Etobicoke,Ontario, Canada M9P 3V6. [email protected] de DiegoKimika Analitikoa Saila; Euskal Herriko Unibertsitatea; 644 P. K.;48080, Bilbao, [email protected] to volume XLISergi D ezEnvironmental Chemistry Department, IIQAB-CID-CSIC, JordiGirona, 18, E-08034 Barcelona, Spain.Olivier F.X. DonardCNRS, Laboratoire de Chimie Analytique Bio-inorganique etEnvironnement, He`lioparc, 2 avenue du President Angot, F-64000Pau, France. [email protected] DrouinSpectroscopy Section, Laboratory Services Branch, Ontario Ministryof the Environment, Ontario, Canada M9P [email protected] EbdonSchool of Environmental Sciences, University of Plymouth,Drake Circus, Plymouth PL4 8AA, [email protected] EzzellDionex Corporation, 1515 West 2200 South, Suite A, Salt Lake City,UT 84119-7209, USA [email protected] FangResearch Center for Analytical Sciences, Northeastern University,Chemistry Building, Box 332, Shenyang 110006, P.R. [email protected] FeldmannDepartment of Chemistry, University of Aberdeen, Meston Walk,Old Aberdeen AB24 3UE, Scotland, [email protected] S. FisherSchool of Environmental Sciences, University of Phymouth,Drake Circus, Phymouth PL4 8AA, [email protected] Luis Luque Garc aDepartment of Analytical Chemistry Annex C-3, Campus ofRabanales, University of Cordoba, E- 4071 Cordoba (Spain)[email protected] GoesslerInstitute of Chemistry, Analytical Chemistry, Universita tsplatz 1,8010 Graz, Austria. [email protected] to volume XLIviiiMiguel de La GuardiaDepartment of Analytical Chemistry, Faculty of Chemistry,University of Valencia, Dr Moliner St. 50. Burjassot, 46100-Valencia,Spain. [email protected] HeisterkampMettlerToledo GmbH, D-35396 Giessen, [email protected] HintelmannDepartment of Chemistry, Trent University, Peterborough, Ontario,K9J 7B8, Canada. [email protected] HlavayUniversity of Veszprem, Department of Earth and EnvironmentalSciences, H-8200 Veszprem, Egyetem str. 10, P.O. Box 158 [email protected] HoenigCentre for Veterinary and Agrochemical Research (CERVA),Leuvensesteenweg 17, B-3080 Tervuren, [email protected] IhnatPacic Agri-Food Research Centre, Agriculture and Agri-FoodCanada Summerland, BC, Canada, V0H 1Z0. [email protected] ItabashiDepartment of Applied Chemistry, Faculty of Engineering, GunmaUniversity, Kiryu, Gunma 376-8515, [email protected] Ake JonssonAnalytical Chemistry, Lund University, P.O. Box 124, S-221 00Lund, Sweden. [email protected] KawabataPerkinElmer Instruments, 71 Four Valley Drive, Concord, Ontario,Canada, L4K 4V8. [email protected] E. KingCEM Corporation, 3100 Smith Farm Road, P.O. Box 200, Matthews,North Carolina 28106-0200, USA. [email protected] KishiPerkinElmer Instruments, 71 Four Valley Drive, Concord, Ontario,Canada, L4K 4V8.ixContributors to volume XLIGunter KnappGraz University of Technology, A-8010 Graz, Technikerstrase 4,Graz, Austria. [email protected] G. KratochvilDepartment of Chemistry, University of Alberta, Edmonton, Alberta,Canada T6G 2G2. [email protected] KruppCNRS, Laboratoire de Chimie Analytique Bio-inorganique etEnvironnement, He`lioparc, 2 avenue du President Angot, F-64000Pau, France.Doris KuehneltInstitute of Chemistry, Analytical Chemistry, Universita tsplatz 1,8010 Graz, Austria. [email protected] Ponce de LeonDepartment of Chemistry, University of Cincinnati, P.O. Box 210172,Cincinnati, OH 45221-0172, USA.Maurice LeroyEuropean Commission, JRC-170, P.O. Box 2340, 76125 Karlsruhe,GermanyFuhe LiAir Liquide Balazs Analytical Services, 46409 Landing Pky,Frement, CA 94538, USA.Ryszard obin skiCNRS UMR 5034 Helioparc 2, av. Pr. Angot F-64053 PAU, [email protected] MadridDepartamento de Quimica Analitica Facultad de Ciencias Quimicas,Universidad Complutense de Madrid 28040 Madrid, Spain.Lennart MathiassonAnalytical Chemistry, Lund University, P.O. Box 124, S-221 00Lund, Sweden. [email protected] MatusiewiczPolitechnika Poznan ska, Department of Analytical Chemistry,60-965, Poznan , Poland. [email protected] n MesterNRC/INMS, 1500, Montreal Rd, Ottawa, ON, K1A 0R6, [email protected] to volume XLIxRoberto MorabitoENEA, UTS PROT, SP Anguillarese 301, IT-00060 S. Maria diGaleria (Rome), Italy. [email protected] MoralesRubioDepartment of Analytical Chemistry, Faculty of Chemistry,University of Valencia, Dr Moliner St. 50 Burjassot, 46100Valencia,Spain. [email protected] NakaharaDepartment of Applied Chemistry, Graduate School of Engineering,Osaka Prefecture University, Sakai, Osaka 599-8531, [email protected] PavageauCNRS, Laboratoire de Chimie Analytique Bio-inorganique etEnvironnement, He`lioparc, 2 avenue du President Angot, F-64000Pau, France.Christophe PecheyranCNRS, Laboratoire de Chimie Analytique Bio-inorganique etEnvironnement, He`lioparc, 2 avenue du President Angot, F-64000Pau, France.Philip J. PottsDepartment of Earth Sciences, The Open University,Walton Hall, Milton Keynes MK7 6AA, [email protected] QuevauvillerEuropean Commission, rue de la Loi 200, B-1049 Brussels, [email protected] RauretDepartament de Quimica Analitica, Universitat de Barcelona,Mart i Franque`s 1-11, 3a Planta, 08028 Barcelona, [email protected] RobinsonSchool of Earth Sciences-Centre for Ore Deposit Research, Universityof Tasmania, Hobart, Tasmania 7001, [email protected] RodushkinAnalytica AB, Aurorum 10, SE-977 75 Lulea , [email protected] to volume XLIRichard E. RussoLawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley,CA 94720, USA. [email protected] SahuquilloDepartament de Quimica Analitica, Universitat de Barcelona,Mart i Franque`s 1-11, 3a Planta, 08028 Barcelona, [email protected] SchramelGSF-Forschungszentrum Institut fu r OekologischeChemie AG, Spurenelementanalytik und Metallspeziation,Postfach 1129 (P.O. Box 1129), D-85758 [email protected] SturgeonNRC/INMS, 1500, Montreal Rd, Ottawa, ON, K1A 0R6, [email protected] SzpunarCNRS UMR 5034 He`lioparc 2, av. Pr. Angot F-64053 PAU, France.Anne P. VonderheideDepartment of Chemistry, University of Cincinnati, P.O. Box 210172,Cincinnati, OH 45221-0172, USA.Scott WillieNRC/INMS 1500 Montreal Road, Ottawa, ON, K1A 0R6, [email protected] to volume XLIxiiWILSON AND WILSONSCOMPREHENSIVE ANALYTICAL CHEMISTRYVOLUMES IN THE SERIESVol. IA Analytical ProcessesGas AnalysisInorganic Qualitative AnalysisOrganic Qualitative AnalysisInorganic Gravimetric AnalysisVol. IB Inorganic Titrimetric AnalysisOrganic Quantitative AnalysisVol. IC Analytical Chemistry of the ElementsVol. IIA Electrochemical AnalysisElectrodepositionPotentiometric TitrationsConductometric TitrationsHigh-Frequency TitrationsVol. IIB Liquid Chromatography in ColumnsGas ChromatographyIon ExchangersDistillationVol. IIC Paper and Thin Layer ChromatographyRadiochemical MethodsNuclear Magnetic Resonance and Electron Spin Resonance MethodsX-Ray SpectrometryVol. IID Coulometric AnalysisVol. III Elemental Analysis with Minute SampleStandards and StandardizationSeparation by Liquid AmalgamsVacuum Fusion Analysis of Gases in MetalsElectroanalysis in Molten SaltsVol. IV Instrumentation for SpectroscopyAtomic Absorption and Fluorescence SpectroscopyDiffuse Reectance SpectroscopyVol. V Emission SpectroscopyAnalytical Microwave SpectroscopyAnalytical Applications of Electron MicroscopyVol. VI Analytical Infrared SpectroscopyVol. VII Thermal Methods in Analytical ChemistrySubstoichiometric Analytical MethodsVol. VIII Enzyme Electrodes in Analytical ChemistryMolecular Fluorescence SpectroscopyPhotometric TitrationsAnalytical Applications of InterferometryVol. IX Ultraviolet Photoelectron and Photoion SpectroscopyAuger Electron SpectroscopyPlasma Excitation in Spectrochemical AnalysisxiiiVol. X Organic Spot Tests AnalysisThe History of Analytical ChemistryVol. XI The Application of Mathematical Statistics inAnalytical Chemistry Mass SpectrometryIon Selective ElectrodesVol. XII Thermal AnalysisPart A. Simultaneous Thermoanalytical Examination by Means ofthe DerivatographPart B. Biochemical and Clinical Applications of Thermometric andThermal AnalysisPart C. Emanation Thermal Analysis and other RadiometricEmanation MethodsPart D. Thermophysical Properties of SolidsPart E. Pulse Method of Measuring Thermophysical ParametersVol. XIII Analysis of Complex HydrocarbonsPart A. Separation MethodsPart B. Group Analysis and Detailed AnalysisVol. XIV Ion-Exchangers in Analytical ChemistryVol. XV Methods of Organic AnalysisVol. XVI Chemical MicroscopyThermomicroscopy of Organic CompoundsVol. XVII Gas and Liquid AnalysersVol. XVIII Kinetic Methods in Chemical AnalysisApplication of Computers in Analytical ChemistryVol. XIX Analytical Visible and Ultraviolet SpectrometryVol. XX Photometric Methods in Inorganic Trace AnalysisVol. XXI New Developments in Conductometric and Oscillometric AnalysisVol. XXII Titrimetric Analysis in Organic SolventsVol. XXIII Analytical and Biomedical Applications of Ion-Selective Field-EffectTransistorsVol. XXIV Energy Dispersive X-Ray Fluorescence AnalysisVol. XXV Preconcentration of Trace ElementsVol. XXVI Radionuclide X-Ray Fluorescence AnalysisVol. XXVII VoltammetryVol. XXVIII Analysis of Substances in the Gaseous PhaseVol. XXIX Chemiluminescence ImmunoassayVol. XXX Spectrochemical Trace Analysis for Metals and MetalloidsVol. XXXI Surfactants in Analytical ChemistryVol. XXXII Environmental Analytical ChemistryVol. XXXIII Elemental Speciation New Approaches for Trace Element AnalysisVol. XXXIV Discrete Sample Introduction Techniques for Inductively CoupledPlasma Mass SpectrometryVol. XXXV Modern Fourier Transform Infrared SpectroscopyVol. XXXVI Chemical Test Methods of AnalysisVol. XXXVII Sampling and Sample Preparation for Field and LaboratoryVol. XXXVIII Countercurrent Chromatography: The Support-Free IiquidStationary PhaseVol. XXXIX Integrated Analytical SystemsVol. XL Analysis and Fate of Surfactants in the Aquatic EnvironmentxivVolumes in the seriesxivContentsContributors to Vol XLI . . . . . . . . . . . . . . . . . . . . . . viVolumes in the Series . . . . . . . . . . . . . . . . . . . . . . . xiiiSeries Editors Preface. . . . . . . . . . . . . . . . . . . . . . . xliiiPreface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xlivAcronyms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xlviChapter 1. Sampling and sample preservation for traceelement analysis . . . . . . . . . . . . . . . . . . . . . . . . 1Byron Kratochvil1.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 11.2 Preliminary considerations . . . . . . . . . . . . . . . 21.2.1 Sampling variability . . . . . . . . . . . . . . . . . . . . . 21.2.2 Sampling strategies . . . . . . . . . . . . . . . 21.2.3 Uncertainties in sampling . . . . . . . . . . . 31.3 Types of samples . . . . . . . . . . . . . . . . . . . . 31.3.1 Judgment samples . . . . . . . . . . . . . . . 31.3.2 Random samples . . . . . . . . . . . . . . . . 41.3.3 Systematic samples . . . . . . . . . . . . . . . 41.3.4 Subsamples . . . . . . . . . . . . . . . . . . . 51.3.5 Composite samples . . . . . . . . . . . . . . . 51.4 Planning the sampling operation . . . . . . . . . . . . 51.4.1 Dening goals. . . . . . . . . . . . . . . . . . 51.4.2 Sampling plans . . . . . . . . . . . . . . . . . 61.5 Statistical sampling. . . . . . . . . . . . . . . . . . . 81.5.1 Introduction. . . . . . . . . . . . . . . . . . . 81.5.2 Minimum number of increments . . . . . . . . 81.5.3 Minimum size of increments in well-mixedparticulate populations . . . . . . . . . . . . . 91.5.4 Sample increment size in segregatedpopulations . . . . . . . . . . . . . . . . . . . 101.5.5 From where should increments be taken? . . . 111.5.6 Model-based sampling . . . . . . . . . . . . . 12xv1.5.7 Balancing economic factors and purpose of datacollection against sample quality . . . . . . . . 131.6 Sample handling and preservation during collection,transport, and storage . . . . . . . . . . . . . . . . . 141.6.1 Handling and storage of samples . . . . . . . . 141.6.2 Sampling equipment . . . . . . . . . . . . . . 161.6.3 Sample containers . . . . . . . . . . . . . . . 161.7 Quality assurance in sampling [24,25] . . . . . . . . . 171.7.1 Overall objectives . . . . . . . . . . . . . . . . 171.7.2 Quality control . . . . . . . . . . . . . . . . . 171.7.3 Quality assessment . . . . . . . . . . . . . . . 171.8 Glossary. . . . . . . . . . . . . . . . . . . . . . . . . 18References . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Selected bibliography . . . . . . . . . . . . . . . . . . . . . 21Chapter 2. Sources of analyte contamination and loss during theanalytical process . . . . . . . . . . . . . . . . . . . . . . . 23Gunter Knapp and Peter Schramel2.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 232.2 Contamination . . . . . . . . . . . . . . . . . . . . . 242.2.1 Materials . . . . . . . . . . . . . . . . . . . . 242.2.2 Reagents . . . . . . . . . . . . . . . . . . . . 272.2.3 Airborne particles . . . . . . . . . . . . . . . . 282.3 Losses . . . . . . . . . . . . . . . . . . . . . . . . . . 292.4 Sampling . . . . . . . . . . . . . . . . . . . . . . . . 342.5 Storage . . . . . . . . . . . . . . . . . . . . . . . . . 352.6 Drying and homogenisation. . . . . . . . . . . . . . . 372.7 Dilution, dissolution and digestion . . . . . . . . . . . 392.8 Separation and preconcentration . . . . . . . . . . . . 412.9 Element measurement . . . . . . . . . . . . . . . . . 42References . . . . . . . . . . . . . . . . . . . . . . . . . . . 42Chapter 3. Calibration approaches for trace element determination 47Douglas C. Baxter and Ilia Rodushkin3.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 473.2 Basic assumptions and some terminology . . . . . . . 483.3 Selection of the calibration approach . . . . . . . . . . 493.4 Statistical evaluation of recovery data . . . . . . . . . 52xviContentsxvi3.5 Linear regression . . . . . . . . . . . . . . . . . . . . 553.5.1 Ordinary linear regression . . . . . . . . . . . 563.5.2 Weighted linear regression . . . . . . . . . . . 593.5.3 Linear regression for data with uncertainties inboth variables . . . . . . . . . . . . . . . . . . 643.6 External calibration. . . . . . . . . . . . . . . . . . . 673.6.1 Estimating uncertainty . . . . . . . . . . . . . 683.6.2 Optimizing precision . . . . . . . . . . . . . . 703.6.3 Accounting for non-constant sensitivity . . . . 723.7 Method of standard additions. . . . . . . . . . . . . . 743.7.1 Estimating uncertainty . . . . . . . . . . . . . 753.7.2 Optimizing precision . . . . . . . . . . . . . . 763.7.3 Accounting for non-constant sensitivity . . . . 783.8 Internal standardization . . . . . . . . . . . . . . . . 793.8.1 Estimating uncertainty . . . . . . . . . . . . . 803.8.2 Optimizing precision . . . . . . . . . . . . . . 813.9 Isotope dilution . . . . . . . . . . . . . . . . . . . . . 813.9.1 Mass discrimination and detector dead time . . 853.9.2 Estimating uncertainty . . . . . . . . . . . . . 863.9.3 Optimizing precision . . . . . . . . . . . . . . 88Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 90References . . . . . . . . . . . . . . . . . . . . . . . . . . . 90Chapter 4. Stated references for ensuring traceability of traceelement analysis . . . . . . . . . . . . . . . . . . . . . . . . 93Philippe Quevauviller4.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 934.2 Meaning of traceability for chemical measurements . . 944.3 SI units . . . . . . . . . . . . . . . . . . . . . . . . . 964.4 Documented standards . . . . . . . . . . . . . . . . . 964.5 Reference methods . . . . . . . . . . . . . . . . . . . 974.6 Reference materials . . . . . . . . . . . . . . . . . . . 994.6.1 The various categories of materials and relatedrequirements . . . . . . . . . . . . . . . . . . 994.6.2 Production . . . . . . . . . . . . . . . . . . . 1004.6.3 Methods used for material characterisation orcertication . . . . . . . . . . . . . . . . . . . 102xviiContents4.6.4 Use of reference materials . . . . . . . . . . . 1024.6.5 Traceability of reference materials . . . . . . . 1034.7 Specimen banking . . . . . . . . . . . . . . . . . . . 1054.8 Prociency testing . . . . . . . . . . . . . . . . . . . 1054.9 Real-case achievement of traceability of traceelement analysis . . . . . . . . . . . . . . . . . . . . 1064.9.1 Total trace element determinations . . . . . . . 1064.9.2 Operationally dened trace elementdeterminations . . . . . . . . . . . . . . . . . 1084.9.3 Determinations of chemical forms of elements . 1104.10 Conclusions . . . . . . . . . . . . . . . . . . . . . . . 113References . . . . . . . . . . . . . . . . . . . . . . . . . . . 114Chapter 5. Detection methods for the quantitation of traceelements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117Les Ebdon, Andrew S. Fisher, Maria Betti and Maurice Leroy5.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 1175.2 Classical methods . . . . . . . . . . . . . . . . . . . . 1175.3 Flame spectrometry. . . . . . . . . . . . . . . . . . . 1185.3.1 Introduction. . . . . . . . . . . . . . . . . . . 1185.3.2 Theory . . . . . . . . . . . . . . . . . . . . . 1185.3.3 Instrumentation . . . . . . . . . . . . . . . . 1195.3.4 Interferences and background correctiontechniques. . . . . . . . . . . . . . . . . . . . 1215.3.5 Conventional nebulisation . . . . . . . . . . . 1235.3.6 Alternative methods of sample introduction . . 1275.4 Electrothermal AAS. . . . . . . . . . . . . . . . . . . 1355.4.1 Introduction. . . . . . . . . . . . . . . . . . . 1355.4.2 Conventional ET-AAS. . . . . . . . . . . . . . 1365.4.3 Multi-element ET-AAS . . . . . . . . . . . . . 1395.4.4 Chemical vapour generationET-AAS . . . . . 1405.4.5 Speciation . . . . . . . . . . . . . . . . . . . . 1415.5 Inductively coupled plasma-atomic emissionspectrometry . . . . . . . . . . . . . . . . . . . . . . 1425.5.1 Introduction. . . . . . . . . . . . . . . . . . . 1425.5.2 Theory and interferences . . . . . . . . . . . . 142xviiiContentsxviii5.5.3 Instrumentation . . . . . . . . . . . . . . . . 1435.5.4 Figures of merit . . . . . . . . . . . . . . . . . 1525.6 Inductively coupled plasma-mass spectrometry . . . . 1525.6.1 Introduction. . . . . . . . . . . . . . . . . . . 1525.6.2 Theory . . . . . . . . . . . . . . . . . . . . . 1535.6.3 Instrumentation . . . . . . . . . . . . . . . . 1545.6.4 Different types of analysis . . . . . . . . . . . 1565.6.5 Interferences . . . . . . . . . . . . . . . . . . 1565.6.6 Sample introduction techniques . . . . . . . . 1585.6.7 Figures of merit . . . . . . . . . . . . . . . . . 1605.7 Atomic uorescence spectrometry. . . . . . . . . . . . 1605.7.1 Introduction. . . . . . . . . . . . . . . . . . . 1605.7.2 Theory . . . . . . . . . . . . . . . . . . . . . 1625.7.3 Instrumentation . . . . . . . . . . . . . . . . 1625.7.4 Sample introduction . . . . . . . . . . . . . . 1635.7.5 Interferences . . . . . . . . . . . . . . . . . . 1635.7.6 Figures of merit . . . . . . . . . . . . . . . . . 1635.8 Other atomic absorption, emission and uorescencemethods of detection . . . . . . . . . . . . . . . . . . 1645.8.1 Microwave induced plasma . . . . . . . . . . . 1645.8.2 Direct current plasma. . . . . . . . . . . . . . 1655.9 Secondary ion mass spectrometry. . . . . . . . . . . . 1655.9.1 Introduction. . . . . . . . . . . . . . . . . . . 1655.9.2 Practical principles . . . . . . . . . . . . . . . 1675.9.3 Sensitivity and quantication. . . . . . . . . . 1685.10 Glow discharge mass spectrometry . . . . . . . . . . . 1715.10.1 Introduction. . . . . . . . . . . . . . . . . . . 1715.10.2 Glow discharge processes . . . . . . . . . . . . 1735.10.3 Applications to trace element analysis . . . . . 1755.11 X-ray uorescence spectrometry . . . . . . . . . . . . 1765.11.1 Introduction. . . . . . . . . . . . . . . . . . . 1765.11.2 Instrumentation . . . . . . . . . . . . . . . . 1775.11.3 Matrix effects . . . . . . . . . . . . . . . . . . 1775.11.4 Quantitative and trace analysis . . . . . . . . 1785.12 UV/Visible spectrophotometric and chemiluminescencetechniques. . . . . . . . . . . . . . . . . . . . . . . . 1795.12.1 UV/Visible spectrophotometric techniques . . . 179xixContents5.12.2 Molecular uorescence andchemiluminescence detection . . . . . . . . . . 1815.13 Electrochemical methods . . . . . . . . . . . . . . . . 1835.13.1 Differential pulse anodic stripping voltammetry 1835.13.2 Cathodic and adsorptive stripping voltammetry 1845.13.3 Ion selective electrodes . . . . . . . . . . . . . 185References . . . . . . . . . . . . . . . . . . . . . . . . . . . 186DIGESTION AND EXTRACTION APPROACHESChapter 6. Wet digestion methods . . . . . . . . . . . . . . . . . 193Henryk Matusiewicz6.1 Introduction and brief history . . . . . . . . . . . . . 1936.2 Nomenclature . . . . . . . . . . . . . . . . . . . . . . 1946.3 Bibliography . . . . . . . . . . . . . . . . . . . . . . 1946.4 Reagents and vessel materials for wet digestionprocedures . . . . . . . . . . . . . . . . . . . . . . . 1956.5 Wet acid digestion (decomposition and dissolution)procedures . . . . . . . . . . . . . . . . . . . . . . . 1996.5.1 Open systems . . . . . . . . . . . . . . . . . . 1996.5.2 Closed systems . . . . . . . . . . . . . . . . . 2036.5.3 Flow systems . . . . . . . . . . . . . . . . . . 2106.5.4 Vapor-phase acid digestion (gas-phase reactions) 2136.5.5 Efciency of wet digestion (decomposition anddissolution) procedures . . . . . . . . . . . . . 2166.5.6 Comparison of wet digestion techniques . . . . 2196.5.7 Digestion systems (instrumentation,equipment, automation) . . . . . . . . . . . . 2206.5.8 Safety of acid digestions (sample aciddigestion safety). . . . . . . . . . . . . . . . . 2216.6 Conclusions and future trends . . . . . . . . . . . . . 224References . . . . . . . . . . . . . . . . . . . . . . . . . . . 228Chapter 7. Dry ashing . . . . . . . . . . . . . . . . . . . . . . . 235Michel Hoenig7.1 General considerations . . . . . . . . . . . . . . . . . 2357.2 Why dry ashing? . . . . . . . . . . . . . . . . . . . . 2387.3 Oxidation process and dissolution of the residue . . . . 240xxContentsxx7.3.1 Particular case of plant matrices . . . . . . . . 2437.4 Methodology . . . . . . . . . . . . . . . . . . . . . . 2447.4.1 Heating devices . . . . . . . . . . . . . . . . . 2447.4.2 Ashing vessels . . . . . . . . . . . . . . . . . 2457.4.3 Inuence of the sample composition . . . . . . 2467.4.4 Operating modes for environmental samples . . 2467.5 Particular cases of arsenic and selenium . . . . . . . . 2487.5.1 Ashing aids . . . . . . . . . . . . . . . . . . . 2507.5.2 What to do? . . . . . . . . . . . . . . . . . . . 2517.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . 253References . . . . . . . . . . . . . . . . . . . . . . . . . . . 254Chapter 8. Microwave based extraction . . . . . . . . . . . . . . 257Edward E. King and David Barclay8.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 2578.2 Brief history of industrial microwave devices. . . . . . 2578.3 Microwave theory . . . . . . . . . . . . . . . . . . . . 2588.4 Microwave laboratory equipment . . . . . . . . . . . . 2638.4.1 Magnetron . . . . . . . . . . . . . . . . . . . 2648.4.2 Power application . . . . . . . . . . . . . . . . 2678.4.3 Waveguide . . . . . . . . . . . . . . . . . . . 2678.4.4 Microwave cavity . . . . . . . . . . . . . . . . 2678.4.5 Reected energy . . . . . . . . . . . . . . . . 2678.4.6 Mode stirrer and turntables . . . . . . . . . . 2688.4.7 Microwave compatible materials . . . . . . . . 2698.5 Vessels . . . . . . . . . . . . . . . . . . . . . . . . . 2708.5.1 Materials . . . . . . . . . . . . . . . . . . . . 2718.5.2 Structural components . . . . . . . . . . . . . 2728.5.3 Safety . . . . . . . . . . . . . . . . . . . . . . 2728.5.4 Closed vessels . . . . . . . . . . . . . . . . . . 2738.5.5 Vent and reseal vessels . . . . . . . . . . . . . 2748.5.6 Open vessels . . . . . . . . . . . . . . . . . . 2748.6 Control systems . . . . . . . . . . . . . . . . . . . . . 2758.6.1 Power/time . . . . . . . . . . . . . . . . . . . 2758.6.2 Pressure. . . . . . . . . . . . . . . . . . . . . 2758.6.3 Temperature . . . . . . . . . . . . . . . . . . 278xxiContents8.6.4 Power optimization feedback . . . . . . . . . . 2808.7 Methodology . . . . . . . . . . . . . . . . . . . . . . 2818.7.1 Pressurized closed vessel extractions . . . . . . 2828.7.2 Atmospheric open vessel extractions . . . . . . 2838.8 Sample types . . . . . . . . . . . . . . . . . . . . . . 2858.8.1 Inorganic . . . . . . . . . . . . . . . . . . . . 2858.8.2 Leaches and other partial extractions . . . . . 2868.8.3 Complete dissolutions. . . . . . . . . . . . . . 2878.8.4 High-temperature extractions . . . . . . . . . 2888.8.5 Complex sequential extractions. . . . . . . . . 2908.8.6 Organic . . . . . . . . . . . . . . . . . . . . . 2918.8.7 Carbohydrates . . . . . . . . . . . . . . . . . 2928.8.8 Proteins . . . . . . . . . . . . . . . . . . . . . 2938.8.9 Fats, oils, and waxes . . . . . . . . . . . . . . 2948.9 Advanced applications . . . . . . . . . . . . . . . . . 2978.9.1 Clean chemistry. . . . . . . . . . . . . . . . . 2978.9.2 Concentration/evaporation . . . . . . . . . . . 2978.10 Conclusions . . . . . . . . . . . . . . . . . . . . . . . 298Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 299References . . . . . . . . . . . . . . . . . . . . . . . . . . . 299Chapter 9. Fusion and uxes . . . . . . . . . . . . . . . . . . . 301Fernand Claisse9.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 3019.2 Fusion in lithium borates . . . . . . . . . . . . . . . . 3019.2.1 General . . . . . . . . . . . . . . . . . . . . . 3019.3 The key to successful fusion beads . . . . . . . . . . . 3059.3.1 The concept of neutrality . . . . . . . . . . . 3059.3.2 The optimal ux and crystallization . . . . . . 3069.3.3 Cracking of fused beads . . . . . . . . . . . . . 3079.3.4 Loss and retention of sulfur. . . . . . . . . . . 3089.4 Application to trace element analysis. . . . . . . . . . 3089.4.1 Maximizing X-ray intensities . . . . . . . . . . 3089.4.2 Minimizing background. . . . . . . . . . . . . 3099.5 Features of fusion for trace elements . . . . . . . . . . 309References . . . . . . . . . . . . . . . . . . . . . . . . . . . 310xxiiContentsxxiiChapter 10. Supercritical uid extraction . . . . . . . . . . . . . 313Roberto Alzaga, Sergi D ez and Josep M. Bayona10.1 Properties of supercritical uids . . . . . . . . . . . . 31310.2 Instrumentation . . . . . . . . . . . . . . . . . . . . 31610.2.1 Experimental solubility measurements . . . . . 31810.3 SFE of trace elements. . . . . . . . . . . . . . . . . . 31810.3.1 Ligand solubility in SFs. . . . . . . . . . . . . 32610.3.2 ComplexSF solubility . . . . . . . . . . . . . 32810.3.3 SFE process . . . . . . . . . . . . . . . . . . . 32810.4 Organometallic compounds . . . . . . . . . . . . . . . 33210.4.1 Organotin compounds. . . . . . . . . . . . . . 33210.4.2 Organomercury compounds. . . . . . . . . . . 33810.4.3 Organolead compounds . . . . . . . . . . . . . 33910.4.4 Arsenic compounds . . . . . . . . . . . . . . . 33910.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . 339References . . . . . . . . . . . . . . . . . . . . . . . . . . . 340Chapter 11. Accelerated solvent extraction of organometallicand inorganic compounds . . . . . . . . . . . . . . . . . . . 343John L. Ezzell11.1 Accelerated solvent extraction as a samplepreparation technique . . . . . . . . . . . . . . . . . 34311.1.1 Introduction. . . . . . . . . . . . . . . . . . . 34311.1.2 Basic principles of ASE operation. . . . . . . . 34411.1.3 ASE instrumentation . . . . . . . . . . . . . . 34511.1.4 ASE methods development . . . . . . . . . . . 34611.1.5 Application areas . . . . . . . . . . . . . . . . 34911.1.6 Summary . . . . . . . . . . . . . . . . . . . . 351References . . . . . . . . . . . . . . . . . . . . . . . . . . . 352Chapter 12. Sonication as a sample preparation method forelemental analysis . . . . . . . . . . . . . . . . . . . . . . . 353Kevin Ashley12.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 35312.2 Methodological considerations . . . . . . . . . . . . . 35412.3 Historical background . . . . . . . . . . . . . . . . . 357xxiiiContents12.4 Applicationssonication and sample preparation . . . 35812.4.1 Environmental analysis. . . . . . . . . . . . . 35812.4.2 Industrial hygiene . . . . . . . . . . . . . . . 36012.4.3 Biological tissues and uids. . . . . . . . . . . 36312.4.4 Other applications . . . . . . . . . . . . . . . 36412.5 Summary . . . . . . . . . . . . . . . . . . . . . . . . 366References . . . . . . . . . . . . . . . . . . . . . . . . . . . 366Chapter 13. Solid phase microextraction as a tool for traceelement determination . . . . . . . . . . . . . . . . . . . . . 371Zolta n Mester and Ralph Sturgeon13.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 37113.2 General description of solid phase microextraction . . . 37313.2.1 Extraction modes . . . . . . . . . . . . . . . . 37313.2.2 Coatings. . . . . . . . . . . . . . . . . . . . . 37513.3 Solid phase microextraction: step-by-step methoddevelopment. . . . . . . . . . . . . . . . . . . . . . . 37513.3.1 Extraction mode selection. . . . . . . . . . . . 37513.3.2 Fiber coating selection . . . . . . . . . . . . . 37613.3.3 Derivatization method selection . . . . . . . . 37613.3.4 Optimization of desorption conditions . . . . . 37613.3.5 Sample volume optimization . . . . . . . . . . 37613.3.6 Optimization of the extraction time. . . . . . . 37713.3.7 Optimization of extraction conditions. . . . . . 37713.3.8 Determination of the linear dynamic range. . . 37813.3.9 Selection of the calibration method . . . . . . . 37813.3.10 Precision of the method . . . . . . . . . . . . . 37913.3.11 Automation of the method . . . . . . . . . . . 37913.4 Solid phase microextraction for speciation analysis . . 38013.4.1 Volatile metal speciesgas chromatographicdetermination . . . . . . . . . . . . . . . . . . 38013.5 Solid phase microextraction as an investigative tool . . 38813.6 Limitations of solid phase microextraction . . . . . . . 38813.7 Isotope dilution calibration in combination with solidphase microextraction. . . . . . . . . . . . . . . . . . 389References . . . . . . . . . . . . . . . . . . . . . . . . . . . 390xxivContentsxxivChapter 14. Solid-phase extraction . . . . . . . . . . . . . . . . 393Valerie Camel14.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 39314.2 Theory . . . . . . . . . . . . . . . . . . . . . . . . . 39314.2.1 Presentation of the technique. . . . . . . . . . 39414.2.2 Operation . . . . . . . . . . . . . . . . . . . . 40014.2.3 Advantages of the technique . . . . . . . . . . 40314.3 Step-by-step method development guide . . . . . . . . 41014.3.1 Selection of solid sorbent . . . . . . . . . . . . 41014.3.2 Inuential parameters . . . . . . . . . . . . . 43214.4 Applications of SPE to the determination of sometrace elements . . . . . . . . . . . . . . . . . . . . . 43914.4.1 Chromium. . . . . . . . . . . . . . . . . . . . 43914.4.2 Iron . . . . . . . . . . . . . . . . . . . . . . . 44314.4.3 Mercury . . . . . . . . . . . . . . . . . . . . . 44514.4.4 Selenium . . . . . . . . . . . . . . . . . . . . 44514.4.5 Tin . . . . . . . . . . . . . . . . . . . . . . . 44514.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . 450References . . . . . . . . . . . . . . . . . . . . . . . . . . . 451Chapter 15. Chelation solvent extraction for separation ofmetal ions . . . . . . . . . . . . . . . . . . . . . . . . . . . 459Hideyuki Itabashi and Taketoshi Nakahara15.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 45915.2 Theoretical considerations . . . . . . . . . . . . . . . 46015.2.1 General principles . . . . . . . . . . . . . . . 46015.2.2 Preconcentration of metal ions . . . . . . . . . 46515.2.3 Mutual separation of metal ions . . . . . . . . 46715.2.4 Speciation of metal ions in natural water. . . . 47215.3 Adsorption of metal ions using chelating resins . . . . 47415.3.1 General principles . . . . . . . . . . . . . . . 47515.3.2 Features of some chelating resins . . . . . . . 47515.4 Application of chelation to sample preparation fortrace metal analysis. . . . . . . . . . . . . . . . . . . 47715.4.1 Procedure for the extraction of metal ionsfrom natural waters. . . . . . . . . . . . . . . 477xxvContents15.4.2 Procedure for the extraction of metal ions fromhigh-purity materials and inorganicsolid samples . . . . . . . . . . . . . . . . . . 48815.4.3 Procedure for the extraction of metal ionsfrom biological samples . . . . . . . . . . . . . 49015.4.4 Procedure for the speciation of metal ions innatural waters . . . . . . . . . . . . . . . . . 491References . . . . . . . . . . . . . . . . . . . . . . . . . . . 492Chapter 16. Cryogenic trapping for speciation analysis . . . . . . 495Marie-Pierre Pavageau, Eva Krupp, Alberto de Diego,Christophe Pecheyran and Olivier F.X. Donard16.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 49516.2 Denition of volatile species . . . . . . . . . . . . . . 50216.3 Physico-chemical principles and processes associatedwith cryofocusing . . . . . . . . . . . . . . . . . . . . 50416.4 Analytical constraints. . . . . . . . . . . . . . . . . . 50916.4.1 Removal of CO2 . . . . . . . . . . . . . . . . . 51016.4.2 Water removal . . . . . . . . . . . . . . . . . 51216.5 Sample preservation and stability . . . . . . . . . . . 51716.6 Instrumentation for cryogenic trapping and selectedapplications. . . . . . . . . . . . . . . . . . . . . . . 52016.6.1 Cryosampler for determination of industrialand environmental VMCs . . . . . . . . . . . 52016.6.2 Cryogenic trapping for speciation analysis . . . 523References . . . . . . . . . . . . . . . . . . . . . . . . . . . 529Chapter 17. Biotrapping as an alternative to metalpreconcentration and speciation . . . . . . . . . . . . . . . . 533Yolanda Madrid and Carmen Ca mara17.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 53317.2 General characteristics of biological substrates. . . . . 53517.2.1 Algae . . . . . . . . . . . . . . . . . . . . . . 53517.2.2 Bacteria . . . . . . . . . . . . . . . . . . . . . 53617.2.3 Fungi . . . . . . . . . . . . . . . . . . . . . . 537xxviContentsxxvi17.3 Uptake mechanisms . . . . . . . . . . . . . . . . . . 53817.4 Working procedures. . . . . . . . . . . . . . . . . . . 54117.4.1 Immobilisation . . . . . . . . . . . . . . . . . 54117.5 Applications. . . . . . . . . . . . . . . . . . . . . . . 54617.5.1 Analytical applications . . . . . . . . . . . . . 54617.5.2 Technological applications . . . . . . . . . . . 55617.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . 557References . . . . . . . . . . . . . . . . . . . . . . . . . . . 557Chapter18Membrane extraction . . . . . . . . . . . . . . . . . . . . . 559Jan Ake Jonsson and Lennart Mathiasson18.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 55918.2 Membrane extraction techniques . . . . . . . . . . . . 55918.2.1 Supported liquid membrane extraction (SLM) . 56018.2.2 Microporous membrane liquid liquidextraction (MMLLE) . . . . . . . . . . . . . . 56518.3 Chemical principles for metal extraction . . . . . . . . 56618.4 Properties of membrane extraction . . . . . . . . . . . 56618.4.1 Clean-up and selectivity . . . . . . . . . . . . 56718.4.2 Enrichment . . . . . . . . . . . . . . . . . . . 56818.4.3 Automation and unattended operation . . . . . 56918.4.4 Solvent consumption . . . . . . . . . . . . . . 57018.5 Experimental set-up . . . . . . . . . . . . . . . . . . 57018.5.1 Flow systems for membrane extraction. . . . . 57018.5.2 How to set up a membrane extractionexperiment for metal ions. . . . . . . . . . . . 571Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 574References . . . . . . . . . . . . . . . . . . . . . . . . . . . 574Chapter 19. Derivatization and vapor generation methods fortrace element analysis and speciation . . . . . . . . . . . . . 577Yong Cai19.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 57719.2 Theory . . . . . . . . . . . . . . . . . . . . . . . . . 57819.2.1 Grignard reactions . . . . . . . . . . . . . . . 57819.2.2 Hydride generation . . . . . . . . . . . . . . . 579xxviiContents19.2.3 Aqueous derivatization with tetraalkyl(aryl)borates . . . . . . . . . . . . . . . . . . 58019.3 Method development . . . . . . . . . . . . . . . . . . 58319.3.1 Grignard reactions . . . . . . . . . . . . . . . 58319.3.2 Aqueous derivatization . . . . . . . . . . . . . 58419.4 Applications. . . . . . . . . . . . . . . . . . . . . . . 585Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 590References . . . . . . . . . . . . . . . . . . . . . . . . . . . 590Chapter 20. Laser ablation sampling . . . . . . . . . . . . . . . 593Richard E. Russo and David P. Baldwin20.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 59320.2 Experimental system . . . . . . . . . . . . . . . . . . 59420.3 Ablation detection systems . . . . . . . . . . . . . . . 59920.4 Calibration . . . . . . . . . . . . . . . . . . . . . . . 60120.5 Fractionation . . . . . . . . . . . . . . . . . . . . . . 60320.6 Conclusion . . . . . . . . . . . . . . . . . . . . . . . 604Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 606References . . . . . . . . . . . . . . . . . . . . . . . . . . . 606Chapter 21. Flow injection techniques for sample pretreatment . . 611Zhao-Lun Fang21.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 61121.1.1 General . . . . . . . . . . . . . . . . . . . . . 61121.1.2 General features of ow injection on-linesample pretreatment systems. . . . . . . . . . 61221.1.3 Classication of FI sample pretreatmentsystems. . . . . . . . . . . . . . . . . . . . . 61221.1.4 Principles and general guidelines for thedevelopment of FI systems . . . . . . . . . . . 61321.1.5 Practical hints for manipulation of FI equipment 61421.2 FI liquidliquid extraction systems. . . . . . . . . . . 61521.2.1 Introduction. . . . . . . . . . . . . . . . . . . 61521.2.2 Apparatus for FI liquidliquid extraction . . . 61721.2.3 Guidelines for the development of FIliquidliquid extraction systems . . . . . . . . 62321.2.4 Typical manifolds for FI liquidliquid extraction 62421.3 FI solid phase extraction systems. . . . . . . . . . . . 626xxviiiContentsxxviii21.3.1 Introduction. . . . . . . . . . . . . . . . . . . 62621.3.2 Sorption media for FI solid phase extraction . . 62721.3.3 Guidelines for the development of FI solidphase extraction systems . . . . . . . . . . . . 62921.3.4 Typical manifolds for FI solid phase extraction. 63021.4 FI vapor generation systems . . . . . . . . . . . . . . 63521.4.1 Introduction. . . . . . . . . . . . . . . . . . . 63521.4.2 Gasliquid separators for FI vapor generation . 63521.4.3 Guidelines for development of FI vaporgeneration systems . . . . . . . . . . . . . . . 63621.4.4 Typical FI manifolds for VG-AAS . . . . . . . . 63821.5 FI gas diffusion systems . . . . . . . . . . . . . . . . 64121.5.1 General . . . . . . . . . . . . . . . . . . . . . 64121.5.2 Gas-diffusion separators . . . . . . . . . . . . 64121.5.3 Typical FI manifolds for gas-diffusion separationand preconcentration . . . . . . . . . . . . . . 64221.6 FI on-line sample digestion . . . . . . . . . . . . . . . 64321.6.1 Introduction. . . . . . . . . . . . . . . . . . . 64321.6.2 FI on-line sample digestion systems for AAS . . 64421.6.3 FI digestion systems coupled to VG-AAS . . . . 64421.6.4 FI systems for digestion of solid samples in AAS 64521.6.5 FI pretreatment systems with on-linephoto-oxidation by UV irradiation . . . . . . . 646References . . . . . . . . . . . . . . . . . . . . . . . . . . . 646Chapter 22. Automation of sample preparation . . . . . . . . . . 649Maria Dolores Luque de Castro and Jose Luis Luque Garc a22.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 64922.1.1 Generalities . . . . . . . . . . . . . . . . . . . 64922.1.2 Principal shortcomings in automating samplepreparation . . . . . . . . . . . . . . . . . . . 65022.1.3 Batch versus serial approaches to automatedsample preparation . . . . . . . . . . . . . . . 65122.1.4 Bar codes: a necessary tool in automatingroutine analyses . . . . . . . . . . . . . . . . 65222.2 Automation of liquid sample preparation. . . . . . . . 653xxixContents22.2.1 Continuous systems. . . . . . . . . . . . . . . 65322.2.2 Discontinuous approaches . . . . . . . . . . . 65622.3 Automation of solid sample preparation . . . . . . . . 65922.3.1 One-step approaches to automation andacceleration of solid sample preparation . . . . 65922.3.2 Direct solid sampling . . . . . . . . . . . . . . 66022.4 Robotics . . . . . . . . . . . . . . . . . . . . . . . . . 66022.4.1 Workstations, robots, modules and peripherals. 66222.4.2 The role of robots in the analytical process . . . 67022.4.3 Analytical scope of robotics for samplepreparation . . . . . . . . . . . . . . . . . . . 67422.5 Advantages and disadvantages of automationof sample preparation. . . . . . . . . . . . . . . . . . 67622.6 Future prospects . . . . . . . . . . . . . . . . . . . . 677References . . . . . . . . . . . . . . . . . . . . . . . . . . . 678MATRICESChapter 23. Sample preparation for crude oil, petroleum productsand polymers . . . . . . . . . . . . . . . . . . . . . . . . . 683Robert I. Botto23.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 68323.1.1 Nature of petroleum crude, products andpolymers . . . . . . . . . . . . . . . . . . . . 68323.1.2 Element context and species in petroleumcrude, products and polymers. . . . . . . . . . 68623.1.3 Sample preparation challenges for traceelement analysis . . . . . . . . . . . . . . . . 69123.2 Sample preparation techniques and instrumentation . 69323.2.1 Ashing techniques . . . . . . . . . . . . . . . 69323.2.2 Acid mineralization techniques . . . . . . . . . 69723.2.3 Oxygen combustion . . . . . . . . . . . . . . . 70423.2.4 Sample component separations/extractivesample preparation . . . . . . . . . . . . . . . 70623.2.5 Organic sample dilutions and dissolutions . . . 70723.2.6 Stable emulsions . . . . . . . . . . . . . . . . 70923.2.7 Scrubber sampling for C1C4 hydrocarbonsand gases . . . . . . . . . . . . . . . . . . . . 711xxxContentsxxx23.3 Cleanliness and quality assurance . . . . . . . . . . . 71323.3.1 Equipment cleaning. . . . . . . . . . . . . . . 71323.3.2 Clean techniques and disposable equipment . . 71423.3.3 Quality assurance. . . . . . . . . . . . . . . . 715Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 718References . . . . . . . . . . . . . . . . . . . . . . . . . . . 719Chapter 24. Sample preparation of geological samples, soilsand sediments . . . . . . . . . . . . . . . . . . . . . . . . . 723Philip J. Potts and Philip Robinson24.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 72324.2 Sample preparation . . . . . . . . . . . . . . . . . . . 72324.2.1 Sample collection . . . . . . . . . . . . . . . . 72424.2.2 Crushing and grinding . . . . . . . . . . . . . 72624.2.3 Selecting an appropriate test portion . . . . . . 72724.3 Choice of approach . . . . . . . . . . . . . . . . . . . 72824.3.1 Fitness-for-purpose . . . . . . . . . . . . . . . 72824.3.2 Choice of sample preparation procedure basedon choice of technique. . . . . . . . . . . . . . 72824.3.3 Choice of sample preparation based on thecharacteristics of elements . . . . . . . . . . . 72924.4 Methods that do not require any sample digestionin situ methods of analysis . . . . . . . . . . . . . . . 73024.4.1 Portable X-ray uorescence . . . . . . . . . . . 73024.4.2 Gamma spectrometry . . . . . . . . . . . . . . 73224.4.3 Laser ablation techniques and other microprobe/microanalytical techniques . . . . . . . . . . . 73224.5 Methods based on solid samples . . . . . . . . . . . . 73324.5.1 Direct determinations on powders . . . . . . . 73324.5.2 Powder pellet for XRF . . . . . . . . . . . . . 73424.5.3 Glass disks for XRF trace determinations . . . 73424.6 Dissolution methods based on acid attack . . . . . . . 73524.6.1 Properties of acids used in the decomposition ofgeological materials . . . . . . . . . . . . . . . 73624.6.2 Open vessel and low-pressure acid digestion . . 738xxxiContents24.6.3 HFHNO3 decomposition method in Savillexwscrew top vials . . . . . . . . . . . . . . . . . 74024.6.4 Closed vessel high pressure acid digestion . . . 74024.6.5 HF/H2SO4 decomposition method in closed,high pressure vessels . . . . . . . . . . . . . . 74224.6.6 HF/HClO4HCl decomposition method in closed,high pressure vessels . . . . . . . . . . . . . . 74224.6.7 Microwave oven digestion. . . . . . . . . . . . 74324.6.8 Partial acid attack . . . . . . . . . . . . . . . 74424.6.9 Difcult minerals . . . . . . . . . . . . . . . . 74524.7 Decomposition by molten salt fusion . . . . . . . . . . 75024.7.1 Total fusion . . . . . . . . . . . . . . . . . . . 75024.7.2 A LiBO2 fusion procedure . . . . . . . . . . . 75224.7.3 Sintering . . . . . . . . . . . . . . . . . . . . 75224.7.4 Fire assay . . . . . . . . . . . . . . . . . . . . 75224.8 Pre-concentration and separation procedures . . . . . 75324.8.1 Ion exchange . . . . . . . . . . . . . . . . . . 75324.8.2 Solvent extraction and co-precipitation . . . . . 75424.8.3 Vapour generation . . . . . . . . . . . . . . . 75524.9 Sequential extractions and dissolutions . . . . . . . . 75524.9.1 Procedure of Tessier et al. . . . . . . . . . . . 75624.9.2 The BCR method . . . . . . . . . . . . . . . 75724.9.3 Selective extractions for geochemicalexploration . . . . . . . . . . . . . . . . . . . 75724.10 Summary and conclusions . . . . . . . . . . . . . . . 758References . . . . . . . . . . . . . . . . . . . . . . . . . . . 758Chapter 25. Sample preparation for food analysis. . . . . . . . . 765Milan Ihnat25.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 76525.2 Literature . . . . . . . . . . . . . . . . . . . . . . . . 76625.2.1 Books on sample treatment, decomposition. . . 76725.2.2 Books including chapters, sections on ordiscussing sample treatment, decomposition . . 76725.2.3 Reviews on sample treatment, decomposition . 76725.2.4 Other reviews including coverage of sampletreatment, decomposition . . . . . . . . . . . 768xxxiiContentsxxxii25.2.5 Papers, publications, containing (major) writingon sample treatment . . . . . . . . . . . . . . 76825.3 Pretreatment . . . . . . . . . . . . . . . . . . . . . . 76825.4 Classication of sample treatment methods . . . . . . 77025.5 Compilation of sample treatment methods for foods . . 77025.5.1 No treatment . . . . . . . . . . . . . . . . . . 83325.5.2 Dry ashing . . . . . . . . . . . . . . . . . . . 83425.5.3 Wet digestionconventional . . . . . . . . . . 83625.5.4 Wet digestionmicrowave-assisted. . . . . . . 83825.5.5 Slurry sample preparation . . . . . . . . . . . 83825.6 Specic cases: methods, elements, matrices . . . . . . 83925.6.1 Analytical method. . . . . . . . . . . . . . . . 83925.6.2 Elements . . . . . . . . . . . . . . . . . . . . 84125.6.3 Matrix and constituents . . . . . . . . . . . . 84225.7 Examples of specic, recommended sample treatmentprocedures . . . . . . . . . . . . . . . . . . . . . . . 84325.7.1 Conventional wet digestion with nitric andperchloric acids. . . . . . . . . . . . . . . . . 84325.7.2 Dry ashing with or without ashing aid . . . . . 84525.7.3 Microwave-assisted wet digestion. . . . . . . . 84525.8 Closing remarks. . . . . . . . . . . . . . . . . . . . . 846References . . . . . . . . . . . . . . . . . . . . . . . . . . . 847Chapter 26. The determination of trace elements in water . . . . 857Scott N. Willie26.1 Direct methods of determination . . . . . . . . . . . . 85726.2 Preconcentration techniquesmultielement . . . . . . 86026.3 Preconcentrationindividual elements. . . . . . . . . 86526.4 Determination of trace elements as volatile species . . 86526.5 Mercury . . . . . . . . . . . . . . . . . . . . . . . . . 87926.6 Luminescence . . . . . . . . . . . . . . . . . . . . . . 88026.7 Voltammetry . . . . . . . . . . . . . . . . . . . . . . 88526.8 Total-reection X-Ray uorescence spectrometry. . . . 89126.9 Conclusions . . . . . . . . . . . . . . . . . . . . . . . 894References . . . . . . . . . . . . . . . . . . . . . . . . . . . 894xxxiiiContentsChapter 27. Aerosol sampling and sample preparation forelemental analysis . . . . . . . . . . . . . . . . . . . . . . . 903Jozsef Hlavay27.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 90327.1.1 Objectives of monitoring . . . . . . . . . . . . 90427.2 Sampling of aerosols . . . . . . . . . . . . . . . . . . 90627.2.1 General considerations . . . . . . . . . . . . . 90627.2.2 Sampling of aerosol by impactors . . . . . . . . 90927.2.3 Ambient sampling for the respirablefraction . . . . . . . . . . . . . . . . . . . . . 91627.2.4 High-volume aerosol samplers . . . . . . . . . 91827.2.5 Speciation aerosol sampling system . . . . . . 92227.2.6 Passive samplers . . . . . . . . . . . . . . . . 92427.3 Sequential extraction schemes for aerosol samples . . . 92427.4 Discussion. . . . . . . . . . . . . . . . . . . . . . . . 930Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 931General terms used in sampling. . . . . . . . . . . . . . . . 931References . . . . . . . . . . . . . . . . . . . . . . . . . . . 932Chapter 28. Sample preparation for industrial waste analysis . . 935Peter Drouin and Ray E. Clement28.1 Types of industrial waste . . . . . . . . . . . . . . . . 93528.2 Safety considerations for industrial waste analysis. . . 93628.3 Sample characteristics and industrial wastesampling . . . . . . . . . . . . . . . . . . . . . . . . 93628.4 Digestions . . . . . . . . . . . . . . . . . . . . . . . . 93828.4.1 Aqueous sample typesUS EPA methods . . . 93928.4.2 Solid sample typesUS EPA methods . . . . . 94228.4.3 Reported studieshot plate digestion . . . . . 94328.4.4 Reported studiesmicrowave digestionmethods . . . . . . . . . . . . . . . . . . . . . 94528.4.5 Ultrasound-assisted extractions . . . . . . . . 94928.4.6 Alkaline digestions . . . . . . . . . . . . . . . 94928.4.7 Laboratory safety . . . . . . . . . . . . . . . . 95028.5 Leach procedures . . . . . . . . . . . . . . . . . . . . 95028.5.1 Toxicity characteristic leaching procedure . . . 95128.5.2 TCLP regulatory limits . . . . . . . . . . . . . 951xxxivContentsxxxiv28.5.3 TCLP method summary. . . . . . . . . . . . . 95228.5.4 TCLP applications . . . . . . . . . . . . . . . 95328.5.5 TCLP and sequential extractions . . . . . . . . 95428.5.6 TCLP limitations . . . . . . . . . . . . . . . . 95628.6 Certied reference materials . . . . . . . . . . . . . . 95728.7 Summary and future developments. . . . . . . . . . . 95728.8 Useful World Wide Websites . . . . . . . . . . . . . . 960Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 961References . . . . . . . . . . . . . . . . . . . . . . . . . . . 961Chapter 29. Sample preparation for semiconductor materials. . . 965Katsu Kawabata, Yoko Kishi, Fuhe Li and Scott Anderson29.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 96529.2 Contamination control . . . . . . . . . . . . . . . . . 96929.2.1 Clean room . . . . . . . . . . . . . . . . . . . 96929.2.2 Equipments, reagents and standards . . . . . . 97129.3 Sample preparation . . . . . . . . . . . . . . . . . . . 97629.3.1 Preparation and analysis of samples . . . . . . 97829.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . 986References . . . . . . . . . . . . . . . . . . . . . . . . . . . 986TRACE ELEMENT SPECIATIONChapter 30. Sampling and sample treatment in the analysis oforganotin compounds in environmental samples . . . . . . . 991Roberto Morabito30.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 99130.2 Critical steps in organotin analysis . . . . . . . . . . . 99430.2.1 Sampling . . . . . . . . . . . . . . . . . . . . 99430.2.2 Storage . . . . . . . . . . . . . . . . . . . . . 99830.2.3 Sample treatment . . . . . . . . . . . . . . . . 100030.3 Improving the quality of organotin measurementsin Europe . . . . . . . . . . . . . . . . . . . . . . . . 100530.4 Detailed procedure for the GCMS determination oforganotin compounds in environmental samples . . . . 1017Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 1020References . . . . . . . . . . . . . . . . . . . . . . . . . . . 1021xxxvContentsChapter 31. Sample preparation for arsenic speciation . . . . . . 1027Walter Goessler and Doris Kuehnelt31.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 102731.2 Occurrence and distribution of arsenicin the environment . . . . . . . . . . . . . . . . . . . 102831.2.1 Marine environment . . . . . . . . . . . . . . 102831.2.2 Terrestrial environment . . . . . . . . . . . . 103131.2.3 Humans . . . . . . . . . . . . . . . . . . . . . 103131.3 Stability of arsenic compounds . . . . . . . . . . . . . 103331.3.1 Arsenite and arsenate . . . . . . . . . . . . . 103431.3.2 Methylarsonous acid and dimethylarsinousacid . . . . . . . . . . . . . . . . . . . . . . . 103531.3.3 Methylarsonic acid and dimethylarsinic acid . . 103631.3.4 Arsenobetaine, arsenocholine, trimethylarsineoxide, and the tetramethylarsonium ion . . . . 103731.3.5 Arsenosugars . . . . . . . . . . . . . . . . . . 103731.4 Extraction of arsenic compounds from environmentalsamples . . . . . . . . . . . . . . . . . . . . . . . . . 103831.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . 1041References . . . . . . . . . . . . . . . . . . . . . . . . . . . 1041Chapter 32. Sample preparation for speciationof selenium. . . . . . . . . . . . . . . . . . . . . . . . . . . 1045Claudia Ponce de Leon, Anne P. Vonderheide andJoseph A. Caruso32.1 Why selenium speciation?. . . . . . . . . . . . . . . . 104532.2 General sample preparation . . . . . . . . . . . . . . 104532.3 Mammals . . . . . . . . . . . . . . . . . . . . . . . . 104632.3.1 Body uid analysis . . . . . . . . . . . . . . . 104632.3.2 Tissue sample analysis . . . . . . . . . . . . . 104932.4 Fish/birds . . . . . . . . . . . . . . . . . . . . . . . . 105032.5 Plants . . . . . . . . . . . . . . . . . . . . . . . . . . 105132.5.1 Leafy plants. . . . . . . . . . . . . . . . . . . 105232.5.2 Broccoli . . . . . . . . . . . . . . . . . . . . . 105332.5.3 Spices (garlic, onion, white clover) . . . . . . . 105332.5.4 Grains. . . . . . . . . . . . . . . . . . . . . . 105432.5.5 Nuts. . . . . . . . . . . . . . . . . . . . . . . 1054xxxviContentsxxxvi32.5.6 Mushrooms . . . . . . . . . . . . . . . . . . . 105432.6 Microorganisms . . . . . . . . . . . . . . . . . . . . . 105532.7 Environmental . . . . . . . . . . . . . . . . . . . . . 105532.7.1 Air. . . . . . . . . . . . . . . . . . . . . . . . 105532.7.2 Water . . . . . . . . . . . . . . . . . . . . . . 105632.7.3 Soil and sediments (solid matrices) . . . . . . . 1058References . . . . . . . . . . . . . . . . . . . . . . . . . . . 1059Chapter 33. Sample preparation for mercury speciation . . . . . 1063Holger Hintelmann33.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 106333.2 Aqueous solution chemistry of methylmercury . . . . . 106333.3 Sample collection, preservation and storage . . . . . . 106533.3.1 Cleaning of sampling and laboratoryequipment. . . . . . . . . . . . . . . . . . . . 106633.3.2 Water sampling . . . . . . . . . . . . . . . . . 106633.3.3 Preservation and storage of water samples . . . 106733.3.4 Preservation and storage of tissue andvegetation samples . . . . . . . . . . . . . . . 106833.3.5 Preservation and storage of soil and sedimentsamples . . . . . . . . . . . . . . . . . . . . . 106833.4 Sample preparation . . . . . . . . . . . . . . . . . . . 106933.4.1 Extraction of methylmercury from water . . . . 107133.4.2 Extraction of methylmercury from soils,sediments and particles . . . . . . . . . . . . . 107233.4.3 Extraction of methylmercury from biologicaltissue . . . . . . . . . . . . . . . . . . . . . . 107333.4.4 Direct techniques involving no samplepreparation . . . . . . . . . . . . . . . . . . . 107433.4.5 Extraction of mercury species other thanmethylmercury . . . . . . . . . . . . . . . . . 107433.5 Quality control . . . . . . . . . . . . . . . . . . . . . 107533.5.1 Artifactual formation of methylmercury . . . . 107533.5.2 Spike recoveries. . . . . . . . . . . . . . . . . 107633.5.3 Reference materials . . . . . . . . . . . . . . . 1077Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 1079References . . . . . . . . . . . . . . . . . . . . . . . . . . . 1079xxxviiContentsChapter 34. Sample preparation for speciation of lead . . . . . . 1081Freddy C. Adams and Monika Heisterkamp34.1 Introduction. . . . . . . . . . . . . . . . . . . . . . . 108134.2 Toxicity of organolead compounds . . . . . . . . . . . 108334.3 The history of leaded gasoline . . . . . . . . . . . . . 108534.4 Properties of organolead compounds . . . . . . . . . . 108834.5 Synthesis of organolead compounds . . . . . . . . . . 109034.6 The biogeochemical cycle of lead . . . . . . . . . . . . 109234.7 Analytical techniques for speciation analysis oforganolead compounds . . . . . . . . . . . . . . . . . 109234.7.1 Hyphenated techniques for organometaldeterminations . . . . . . . . . . . . . . . . . 109334.7.2 Sample preparation . . . . . . . . . . . . . . . 109634.7.3 Sample pretreatment using gaschromatographic separation . . . . . . . . . . 109734.7.4 Extraction recovery . . . . . . . . . . . . . . . 110034.7.5 Separation . . . . . . . . . . . . . . . . . . . 110134.7.6 Detection of organolead compounds afterchromatography. . . . . . . . . . . . . . . . . 110434.7.7 Procedures for the determination of organoleadcompounds in dust material . . . . . . . . . . 110734.7.8 Comparison of the different hyphenatedsystems . . . . . . . . . . . . . . . . . . . . . 1109References . . . . . . . . . . . . . . . . . . . . . . . . . . . 1111Chapter 35. Sample preparation for chromium speciation . . . . 1115Miguel de la Guardia and Angel Morales-Rubio35.1 The element and its reactivity . . . . . . . . . . . . . 111535.2 The presence of Cr in nature and industrial processes . 111735.3 Chemical species of Cr present in real samples. . . . . 111835.4 Analytical methodologies available for determinationof Cr . . . . . . . . . . . . . . . . . . . . . . . . . . 112035.5 Analytical methodologies for Cr speciation in water . . 112035.5.1 Speciation of chromium in aqueous matrices . . 112135.5.2 Types of samples analyzed . . . . . . . . . . . 112135.5.3 Pretreatments and techniques applied . . . . . 1123xxxviiiContentsxxxviii35.5.4 Speciation chromium using atomic spectrometryand MS-based techniques . . . . . . . . . . . . 112435.5.5 Determination of chromium speciation usingmolecular spectrophotometry . . . . . . . . . . 113035.6 Analytical methodologies for Cr speciation in biologicaluids . . . . . . . . . . . . . . . . . . . . . . . . . . 113635.6.1 Speciation of chromium in biological uids . . . 113635.6.2 Types of sam