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IARC Monographs on the Evaluation of Carcinogenic Risks to Humans WORLD HEALTH ORGANIZATION INTERNATIONAL AGENCY FOR RESEARCH ON CANCER IARC Monographs on the Evaluation of Carcinogenic Risks to Humans VOLUME 86 Cobalt in Hard Metals and Cobalt Sulfate, Gallium Arsenide, Indium Phosphide and Vanadium Pentoxide LYON, FRANCE 2006 00 i-iv ok.qxp 31/05/2006 08:38 Page i WORLD HEALTH ORGANIZATION INTERNATIONAL AGENCY FOR RESEARCH ON CANCER IARC Monographs on the Evaluation of Carcinogenic Risks to Humans VOLUME 86 Cobalt in Hard Metals and Cobalt Sulfate, Gallium Arsenide, Indium Phosphide and Vanadium Pentoxide This publication represents the views and expert opinions of an IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, which met in Lyon, 7–14 October 2003 2006 Page ii.qxp 06/06/2006 13:51 Page i IARC MONOGRAPHS In 1969, the International Agency for Research on Cancer (IARC) initiated a programme on the evaluation of the carcinogenic risk of chemicals to humans involving the production of critically evaluated monographs on individual chemicals. The programme was subsequently expanded to include evaluations of carcinogenic risks asso- ciated with exposures to complex mixtures, life-style factors and biological and physical agents, as well as those in specific occupations. The objective of the programme is to elaborate and publish in the form of monographs critical reviews of data on carcinogenicity for agents to which humans are known to be exposed and on specific exposure situations; to evaluate these data in terms of human risk with the help of international working groups of experts in chemical carcinogenesis and related fields; and to indicate where additional research efforts are needed. The lists of IARC evaluations are regularly updated and are available on Internet: http://monographs. iarc.fr/ This project was supported by Cooperative Agreement 5 UO1 CA33193 awarded by the United States National Cancer Institute, Department of Health and Human Services. Additional support has been provided since 1992 by the United States National Institute of Environmental Health Sciences. This publication was made possible, in part, by a Cooperative Agreement between the United States Environ- mental Protection Agency, Office of Research and Development (USEPA-ORD) and the International Agency for Research on Cancer (IARC) and does not necessarily express the views of USEPA-ORD. Published by the International Agency for Research on Cancer, 150 cours Albert Thomas, 69372 Lyon Cedex 08, France ©International Agency for Research on Cancer, 2006 Distributed by WHO Press, World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland (tel.: +41 22 791 3264; fax: +41 22 791 4857; e-mail: [email protected]). Publications of the World Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Convention. All rights reserved. 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 Secretariat 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. 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 authors alone are responsible for the views expressed in this publication. The International Agency for Research on Cancer welcomes requests for permission to reproduce or translate its publications, in part or in full. Requests for permission to reproduce or translate IARC publications − whether for sale or for noncommercial distribution − should be addressed to WHO Press, at the above address (fax: +41 22 791 4806; email: [email protected]). IARC Library Cataloguing in Publication Data Cobalt in Hard Metals and Cobalt Sulfate, Gallium Arsenide, Indium Phosphide and Vanadium Pentoxide/IARC Working Group on the Evaluation of Carcinogenic Risks to Humans (2006 : Lyon, France) (IARC monographs on the evaluation of carcinogenic risks to humans ; v. 86) 1. Arsenic − adverse effects 2. Carcinogens 3. Cobalt − adverse effects 4. Gallium − adverse effects 5. Indium − adverse effects 6. Metals 7. Vanadium compounds − adverse effects 8. Tungsten − adverse effects I. IARC Working Group on the Evaluation of Carcinogenic Risks to Humans II. Series ISBN 92 832 1286 X (NLM Classification: W1) ISSN 1017-1606 PRINTED IN FRANCE 00 i-iv ok.qxp 31/05/2006 08:38 Page iii Cover: Some metallic compounds evaluated in this volume are used in integrated circuit boards which represent a new use of these metals. Cover design by Georges Mollon, IARC 00 i-iv ok.qxp 31/05/2006 08:38 Page iv 000 v-xiv ok.qxp 31/05/2006 08:39 Page v CONTENTS NOTE TO THE READER............................................................................................1 LIST OF PARTICIPANTS............................................................................................3 PREAMBLE ................................................................................................................7 1. Background........................................................................................................9 2. Objective and Scope ..........................................................................................9 3. Selection of Topics for Monographs ..............................................................10 4. Data for Monographs ......................................................................................11 5. The Working Group ........................................................................................11 6. Working Procedures ........................................................................................11 7. Exposure Data..................................................................................................12 8. Studies of Cancer in Humans ..........................................................................14 9. Studies of Cancer in Experimental Animals....................................................17 10. Other Data Relevant to an Evaluation of Carcinogenicity and its Mechanisms ........................................................................................20 11. Summary of Data Reported ............................................................................22 12. Evaluation ........................................................................................................23 13. References........................................................................................................28 GENERAL REMARKS ON THE SUBSTANCES CONSIDERED ........................33 THE MONOGRAPHS................................................................................................35 Metallic Cobalt Particles (with or without Tungsten Carbide)............................37 1. Exposure Data..................................................................................................39 1.1 Chemical and physical data ....................................................................39 1.1.1 Nomenclature ..............................................................................39 1.1.2 Molecular formulae and relative molecular mass ......................40 1.1.3 Chemical and physical properties of the pure substance ............40 1.1.4 Technical products and impurities ..............................................40 1.1.5 Analysis ......................................................................................41 (a) Biological monitoring ..........................................................41 (b) Analytical methods for workplace air and biological monitoring ............................................................................41 (c) Reference values for occupationally non-exposed populations............................................................................41 –v– 000 v-xiv ok.qxp 31/05/2006 08:39 Page vi vi IARC MONOGRAPHS VOLUME 86 1.2 Production and use ..................................................................................48 1.2.1 Production....................................................................................48 (a) Cobalt....................................................................................48 (b) Metallic carbides ..................................................................49 (c) Hard metals ..........................................................................52 (d) Cobalt alloys ........................................................................53 1.2.2 Use ..............................................................................................53 1.3 Occurrence and exposure ........................................................................55 1.3.1 Natural occurrence ......................................................................55 1.3.2 Occupational exposure ................................................................55 (a) Hard-metal production and use ............................................56 (b) Cobalt-containing diamond tooling ......................................60 (c) Alloys containing cobalt ......................................................62 (d) Cobalt pigments ....................................................................62
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