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Elemental Mercury and Inorganic Mercury Compounds : Human Health Aspects

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Elemental Mercury and Inorganic Mercury Compounds : Human Health Aspects This report contains the collective views of an international group of experts and does not necessarily represent the decisions or the stated policy of the United Nations Environment Programme, the International Labour Organization, or the World Health Organization. Concise International Chemical Assessment Document 50 ELEMENTAL MERCURY AND INORGANIC MERCURY COMPOUNDS: HUMAN HEALTH ASPECTS Please note that the pagination and layout of this web version are not identical to the printed CICAD First draft prepared by Dr J.F. Risher, Agency for Toxic Substances and Disease Registry (ATSDR), Atlanta, Georgia, USA Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organization, and the World Health Organization, and produced within the framework of the Inter-Organization Programme for the Sound Management of Chemicals. World Health Organization Geneva, 2003 The International Programme on Chemical Safety (IPCS), established in 1980, is a joint venture of the United Nations Environment Programme (UNEP), the International Labour Organiza- tion (ILO), and the World Health Organization (WHO). The overall objectives of the IPCS are to establish the scientific basis for assessment of the risk to human health and the environment from exposure to chemicals, through international peer review processes, as a prerequisite for the promo- tion of chemical safety, and to provide technical assistance in strengthening national capacities for the sound management of chemicals. The Inter-Organization Programme for the Sound Management of Chemicals (IOMC) was established in 1995 by UNEP, ILO, the Food and Agriculture Organization of the United Nations, WHO, the United Nations Industrial Development Organization, the United Nations Institute for Training and Research, and the Organisation for Economic Co-operation and Development (Partici- pating Organizations), following recommendations made by the 1992 UN Conference on Environ- ment and Development to strengthen cooperation and increase coordination in the field of chemical safety. The purpose of the IOMC is to promote coordination of the policies and activities pursued by the Participating Organizations, jointly or separately, to achieve the sound management of chemicals in relation to human health and the environment. WHO Library Cataloguing-in-Publication Data Elemental mercury and inorganic mercury compounds : human health aspects. (Concise international chemical assessment document ; 50) 1.Mercury - adverse effects 2.Mercury compounds - adverse effects 3.Risk assessment 4.Environmental exposure 5.Occupational exposure I.International Programme on Chemical Safety II.Series ISBN 92 4 153050 2 (NLM Classification: QV 293) ISSN 1020-6167 ©World Health Organization 2003 All rights reserved. Publications of the World Health Organization can be obtained from Marketing and Dissemination, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel: +41 22 791 2476; fax: +41 22 791 4857; email: [email protected]). Requests for permission to reproduce or translate WHO publications — whether for sale or for noncommercial distribution — should be addressed to Publications, at the above address (fax: +41 22 791 4806; email: [email protected]). The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines on maps represent approximate border lines for which there may not yet be full agreement. The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. The World Health Organization does not warrant that the information contained in this publication is complete and correct and shall not be liable for any damages incurred as a result of its use. The Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Germany, provided financial support for the printing of this publication. Printed by Wissenschaftliche Verlagsgesellschaft mbH, D-70009 Stuttgart 10 TABLE OF CONTENTS FOREWORD.....................................................................................................................................................................1 1. EXECUTIVE SUMMARY.............................................................................................................................................4 2. IDENTITY AND PHYSICAL/CHEMICAL PROPERTIES ....................................................................................5 2.1 Elemental mercury ....................................................................................................................................................5 2.2 Inorganic mercury compounds...............................................................................................................................5 3. ANALYTICAL METHODS...........................................................................................................................................6 3.1 Biological samples....................................................................................................................................................6 3.2 Environmental samples ............................................................................................................................................6 4. SOURCES OF HUMAN EXPOSURE.........................................................................................................................7 5. ENVIRONMENTAL TRANSPORT, DISTRIBUTION, AND TRANSFORMATION.....................................7 5.1 Environmental transport and distribution.........................................................................................................8 5.2 Environmental transformation............................................................................................................................8 5.2.1 Air................................................................................................................................................................8 5.2.2 Water...........................................................................................................................................................9 5.2.3 Soil and sediment......................................................................................................................................9 6. ENVIRONMENTAL LEVELS AND HUMAN EXPOSURE.................................................................................9 6.1 Environmental levels ............................................................................................................................................9 6.1.1 Air................................................................................................................................................................9 6.1.2 Water...........................................................................................................................................................9 6.2 Human exposure ...................................................................................................................................................9 6.2.1 Elemental mercury and inorganic mercury compounds ..................................................................10 6.2.2 Elemental mercury in dental amalgam fillings..................................................................................11 6.2.3 Other uses of inorganic forms of mercury ..........................................................................................12 7. COMPARATIVE KINETICS AND METABOLISM IN LABORATORY ANIMALS AND HUMANS.........................................................................................................................................................................12 7.1 Absorption ...........................................................................................................................................................12 7.1.1 Elemental mercury ..................................................................................................................................12 7.1.2 Inorganic mercury compounds.............................................................................................................13 7.2 Distribution ..........................................................................................................................................................13 7.2.1 Elemental mercury ..................................................................................................................................13 7.2.2 Inorganic mercury compounds.............................................................................................................14 7.3 Metabolism...........................................................................................................................................................14 7.4 Elimination and excretion..................................................................................................................................15
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