Environmental Health Criteria 72 PRINCIPLES OF STUDIES ON DISEASES OF SUSPECTED CHEMICAL ETIOLOGY AND THEIR PREVENTION Please note that the layout and pagination of this web version are not identical with the printed version. Diseases of suspected chemical etiology and their prevention, principles of studies on (EHC 72, 19... INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY ENVIRONMENTAL HEALTH CRITERIA 72 PRINCIPLES OF STUDIES ON DISEASES OF SUSPECTED CHEMICAL ETIOLOGY AND THEIR PREVENTION 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 Organisation, or the World Health Organization. Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization World Health Orgnization Geneva, 1987 The International Programme on Chemical Safety (IPCS) is a joint venture of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization. The main objective of the IPCS is to carry out and disseminate evaluations of the effects of chemicals on human health and the quality of the environment. Supporting activities include the development of epidemiological, experimental laboratory, and risk-assessment methods that could produce internationally comparable results, and the development of manpower in the field of toxicology. Other activities carried out by the IPCS include the development of know-how for coping with chemical accidents, coordination of laboratory testing and epidemiological studies, and promotion of research on the mechanisms of the biological action of chemicals. ISBN 92 4 154272 1 The World Health Organization welcomes requests for permission to reproduce or translate its publications, in part or in full. Applications and enquiries should be addressed to the Office of Publications, World Health Organization, Geneva, Switzerland, which will be glad to provide the latest information on any changes made Page 1 of 53 Diseases of suspected chemical etiology and their prevention, principles of studies on (EHC 72, 19... to the text, plans for new editions, and reprints and translations already available. 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CONTENTS PRINCIPLES OF STUDIES ON DISEASES OF SUSPECTED CHEMICAL ETIOLOGY AND THEIR PREVENTION INTRODUCTION 1. SUMMARY 2. DEFINITION OF THE PROBLEM 3. GENERAL APPROACHES IN THE INVESTIGATION OF DISEASES OF SUSPECTED CHEMICAL ETIOLOGY 4. DISEASE APPROACH: RECOGNITION AND DESCRIPTION OF A HEALTH PROBLEM 4.1. General background 4.2. Recognition of the index cases 4.3. Screening of populations for suspected cases 4.4. Case definition 4.5. Case identification 4.6. Importance of pathological studies 4.7. Reporting systems and case records 5. EPIDEMIOLOGICAL APPROACHES: SEARCH FOR DETERMINANTS 5.1. General background 5.2. Collection of information and criteria for obtaining specimens 5.3. In-depth study of cases 5.4. Evaluation of epidemiological data 6. TOXICOLOGICAL APPROACHES: STUDIES ON CHEMICALS POSSIBLY INVOLVED 6.1. Experimental animal studies 6.2. Analysis for toxic substances 6.3. Toxic chemical information data systems Page 2 of 53 Diseases of suspected chemical etiology and their prevention, principles of studies on (EHC 72, 19... 7. PROBLEMS IN ESTABLISHING CHEMICAL ETIOLOGY 7.1. Causation in human disease 7.2. Consideration of a chemical etiology 7.3. Temporal relationships 7.4. Biological plausibility 7.5. Dose-response and dose-effect relationships 7.6. Effects of intervention 7.7. Confirmation of a causal relationship 8. STEPS TO BE TAKEN FOLLOWING THE RECOGNITION OF THE CHEMICAL ETIOLOGY OF AN OUTBREAK 8.1. Preventive action and control 8.2. Surveillance and monitoring system 8.3. Health education 9. THE NEED FOR INTERNATIONAL COOPERATION 9.1. Cooperation and collaboration among countries 9.2. Global and regional activities 9.3. Final recommendations REFERENCES APPENDIX I. LIST OF BACKGROUND PAPERS APPENDIX II. CONCEPTUAL FRAMEWORK USED IN SEVERAL STUDIES LEADING TO IDENTIFICATION OF THE CHEMICAL ETIOLOGY OF OUTBREAKS OF DISEASES APPENDIX III. SUMMARY REPORT ON THE IPCS/WPRO/PRC MEETING ON KASHIN-BECK DISEASE WHO TASK GROUP ON PRINCIPLES OF STUDIES ON DISEASES OF SUSPECTED CHEMICAL ETIOLOGY AND THEIR PREVENTION Members a,c Professor L. Amin-Zaki, Former Professor of Paediatrics (Baghdad), Abu Dhabi, United Arab Emirates a Professor E.A. Bababunmi, Laboratory of Biomembrane Research, Department of Biochemistry, University of Ibadan, College of Medicine, Ibadan, Nigeria a Dr R.V. Bhat, National Institute of Nutrition, Indian Council of Medical Research, Hyderabad, India a,b,d Dr J. Borgoño, University of Chile, Department of International Affairs, Ministry of Health, Santiago, Chile (Vice-Chairman) a Dr Y. Egashira, National Institute of Health, Hatano Research Institute, Food and Drug Research Centre, Hatanoshi, Kanagawa-ken, Japan a,b,d Dr R.A. Goyer, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA a,c,d Dr P. Grandjean, Institute of Community Health, Department of Environmental Medicine, Odense Page 3 of 53 Diseases of suspected chemical etiology and their prevention, principles of studies on (EHC 72, 19... University, Odense, Denmark a Dr V.N. Ivanov, Chita Medical Institute, Chita, USSR a Dr V.V. Ivanov, Department of Pathophysiology, Krasnoyarsk Medical Institute, Krasnoyarsk, USSR a,b,e Dr R.D. Kimbrough, Center for Environmental Health, Centers for Disease Control, Atlanta, Georgia, USA a,d Professor P. Krogh, Department of Microbiology, Royal Dental College, Copenhagen, Denmark (Rapporteur) a,c Dr O.A. Levander, Vitamin and Mineral Nutrition Laboratory, Human Nutrition Research Center, US Department of Agriculture, Beltsville, Maryland, USA a,c Dr K.R. Mahaffey, Division of Standards Development and Technology Transfer, National Institute for Occupational Safety and Health, Cincinnati, Ohio, USA a,d Dr G. Martin-Bouyer, Ministère de la Santé, Direction Générale de la Santé, Paris, France (Rapporteur) a Professor V.A. Nasonova, Institute of Rheumatology, Academy of Medical Sciences of the USSR, Moscow, USSR a,d Professor H.D. Tandon, New Delhi, India (Temporary Adviser) (Chairman) a Professor Yan Jianbo, Haerbin Medical University, Haerbin, People's Republic of China a,b Professor H. Yanagawa, Department of Public Health, Jichi Medical School, Minamikawachi, Tochigi-ken, Japan a Professor Yang Guangqi, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China (Vice-Chairman) a Professor Yu Weihan, Haerbin Medical University, Haerbin, People's Republic of China Observers a Dr Chen Junshi, Department of Nutrition and Food Hygiene, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Chen Xiaoshu, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Chen Qing, Department of Environmental Health, School of Public Health, Beijing Medical University, Beijing, People's Republic of China a Dr Dai Yin, National Institute of Food Safety Control and Inspection, China National Centre for Preventive Medicine, Beijing, People's Republic of China Page 4 of 53 Diseases of suspected chemical etiology and their prevention, principles of studies on (EHC 72, 19... a Dr He Xingzhou, Department of Environmental Hygiene, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Li Guangshen, Institute of Endemic Disease, Norman Bethune University of Medical Sciences, Changchun, Jilin province, People's Republic of China a Professor Li Yurui, Division of Pneumoconiosis, Department of Labour Hygiene, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Liu Yuying, Division of Industrial Toxicology, Department of Labour Hygiene, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Lu Boqin, Division of Industrial Toxicology, Department of Labour Hygiene, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Ma Tai, Tianjin Medical College, Tianjin, People's Republic of China a Professor Niu Shiru, Institute of Health, China National Centre for Preventive Medicine, Beijing, People's Republic of China a Dr Qin Yuhui, Institute for Environmental Health Monitoring, China National Centre for Preventive Medicine, Beijing, People's Republic