TITLE -- COPYRIGHT -- CONTENTS -- NOTE TO READERS OF THE CRITERIA MONOGRAPHS -- PREAMBLE -- WHO TASK GROUP ON ENVIRONMENTAL HEALTH CRITERIA FOR ELEMENTAL SPECIATION IN HUMAN HEALTH RISK ASSESSMENT -- ACRONYMS AND ABBREVIATIONS -- 1. SUMMARY -- 1.1 Scope and purpose of the document -- 1.2 Definitions -- 1.3 Structural aspects of speciation -- 1.4 Analytical techniques and methodology -- 1.5 Bioaccessibility and bioavailability -- 1.6 Toxicokinetics and biomonitoring -- 1.6.1 Toxicokinetics -- 1.6.2 Biomonitoring -- 1.7 Molecular and cellular mechanisms of metal toxicity -- 1.8 Health effects -- 2. DEFINITIONS OF SPECIES AND SPECIATION -- 3. STRUCTURAL ASPECTS OF SPECIATION -- 3.1 Isotopic composition -- 3.2 Electronic and oxidation states -- 3.3 Inorganic and organic compounds and complexes -- 3.4 Organometallic species -- 3.5 Macromolecular compounds and complexes -- 4. ANALYTICAL TECHNIQUES AND METHODOLOGY -- 4.1 Introduction -- 4.2 Sample collection and storage -- 4.3 Sample preparation -- 4.3.1 Preliminary treatment of biological fluids -- 4.3.2 Preliminary treatment of tissues and plants -- 4.3.3 Choice between low molecular mass and high molecular mass compounds -- 4.3.4 Desalting -- 4.3.5 Sample cleanup -- 4.3.6 Extraction procedures -- 4.3.7 Preconcentration of the species -- 4.3.8 Derivatization -- 4.4 Separation techniques -- 4.4.1 Liquid chromatography -- 4.4.2 Gas chromatography -- 4.4.3 Capillary electrophoresis -- 4.4.4 Gel electrophoresis -- 4.5 Sequential extraction schemes for the fractionation of sediments, soils, aerosols, and fly ash -- 4.6 Detection: elemental and molecular -- 4.6.1 Atomic absorption spectrometry -- 4.6.2 Atomic fluorescence spectrometry -- 4.6.3 Atomic emission spectrometry -- 4.6.4 Inductively coupled plasma mass spectrometry -- 4.6.5 Plasma source time-of-flight mass spectrometry.

4.6.6 Glow discharge plasmas as tunable sources for elemental speciation -- 4.6.7 Electrospray mass spectrometry -- 4.6.8 Electrochemical methods -- 4.7 Calibration in elemental speciation analysis -- 4.8 Reference materials -- 4.9 Direct speciation analysis of elements and particles -- 4.10 State of the art -- 5. BIOACCESSIBILITY AND BIOAVAILABILITY -- 5.1 Introduction -- 5.2 Bioaccessibility of elements in soils and sediments -- 5.2.1 Factors affecting the mobility and accessibility of elements in terrestrial (soil) environments -- 5.2.2 Factors affecting the mobility and accessibility of elements in sediment environments -- 5.3 Determinants of bioavailability -- 5.3.1 Uptake by carriers -- 5.3.2 Uptake and physical form -- 5.3.3 Uptake and complexation -- 5.3.4 Selective uptake according to charge and size -- 5.3.5 Selective uptake according to binding affinity for different cationic centres -- 5.3.6 Selective uptake involving kinetic binding traps, with or without accompanying redox reactions -- 5.3.7 Uptake of organometallic compounds -- 5.3.8 Exposure concentration and uptake -- 5.3.9 Competition in the uptake and toxicity of non-nutrient elements -- 5.4 Incorporation of bioaccessibility and bioavailability considerations in risk assessment -- 5.4.1 Bioaccessibility and bioavailability in current approaches to environmental and human risk assessment -- 5.4.2 The biotic ligand model -- 6. TOXICOKINETICS AND BIOLOGICAL MONITORING -- 6.1 Introduction -- 6.2 Absorption -- 6.2.1 Chromium -- 6.2.2 Manganese -- 6.2.3 Iron -- 6.2.4 Cobalt -- 6.2.5 Nickel -- 6.2.6 Copper -- 6.2.7 Arsenic -- 6.2.8 Selenium -- 6.2 9 Cadmium -- 6.2.10 Mercury -- 6.2.11 Lead -- 6.3 Disposition, excretion, and protein binding -- 6.3.1 Chromium -- 6.3.2 Manganese -- 6.3.3 Copper -- 6.3.4 Zinc -- 6.3.5 Arsenic -- 6.3.6 Selenium -- 6.3.7 Silver -- 6.3.8 Cadmium -- 6.3.9 Mercury.

6.3.10 Lead -- 6.4 Biotransformation -- 6.4.1 Chromium -- 6.4.2 Manganese -- 6.4.3 Arsenic -- 6.4.4 Selenium -- 6.4.5 Mercury -- 6.5 Exposure assessment and biological monitoring -- 6.5.1 Exposure assessment -- 6.5.2 Speciation in biological monitoring -- 7. MOLECULAR AND CELLULAR MECHANISMS OF METAL TOXICITY -- 7.1 Introduction -- 7.2 Mechanisms of DNA damage and repair -- 7.3 Metal-protein interactions -- 7.4 Generation of reactive oxygen species -- 7.5 Effects on the immune system -- 7.5.1 Mechanisms of sensitization -- 7.5.2 Immunosuppression -- 8. HEALTH EFFECTS -- 8.1 Introduction -- 8.2 Acute toxicity -- 8.2.1 Chromium -- 8.2.2 Nickel -- 8.2.3 Arsenic -- 8.2.4 Tin -- 8.2.5 Barium -- 8.2.6 Mercury -- 8.2.7 Lead -- 8.3 Sensitization and irritation -- 8.3.1 Chromium -- 8.3.2 Nickel -- 8.3.3 Palladium -- 8.3.4 Platinum -- 8.4 Lung toxicity -- 8.4.1 Cobalt -- 8.5 Neurotoxicity -- 8.5.1 Manganese -- 8.5.2 Tin -- 8.5.3 Mercury -- 8.5.4 Thallium -- 8.5.5 Lead -- 8.6 Nephrotoxicity -- 8.6.1 Cadmium -- 8.7 Reproductive toxicity -- 8.7.1 Nickel -- 8.7.2 Mercury -- 8.8 Genotoxicity -- 8.8.1 Chromium -- 8.8.2 Cobalt -- 8.9 Carcinogenicity -- 8.9.1 Chromium -- 8.9.2 Cobalt -- 8.9.3 Nickel -- 8.9.4 Arsenic -- 9. CONCLUSIONS AND RECOMMENDATIONS -- REFERENCES -- RESUME -- RESUMEN -- INDEX OF ELEMENTS.