Environmental Health Criteria 13 Carbon Monoxide Please note that the layout and pagination of this web version are not identical with the printed version. Carbon monoxide (EHC 13, 1979) INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY ENVIRONMENTAL HEALTH CRITERIA 13 Carbon Monoxide This report contains the collective views of an international group of experts and does not necessarily represent the decisions or the stated policy of either the World Health Organization or the United Nations Environment Programme. Published under the joint sponsorship of the United Nations Environment Programme and the World Health Organization World Health Organization Geneva, 1979 ISBN 92 4 154073 7 (c) World Health Organization 1979 Publications of the World Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Convention. For rights of reproduction or translation of WHO publications, in part or in toto, application should be made to the Office of Publications, World Health Organization, Geneva, Switzerland. The World Health Organization welcomes such applications. 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. CONTENTS ENVIRONMENTAL HEALTH CRITERIA FOR CARBON MONOXIDE 1. SUMMARY AND RECOMMENDATIONS FOR FURTHER STUDIES Page 1 of 105 Carbon monoxide (EHC 13, 1979) 1.1. Summary 1.1.1. Properties and analytical methods 1.1.2. Sources of environmental pollution 1.1.3. Environmental levels 1.1.4. Effects on experimental animals 1.1.5. Effects on man 1.1.6. Evaluation of health risk 1.2. Recommendations for further studies 2. CHEMISTRY AND ANALYTICAL METHODS 2.1. Physical and chemical properties 2.2. Methods of measuring carbon monoxide in ambient air 2.3. Biological monitoring 3. SOURCES OF CARBON MONOXIDE IN THE ENVIRONMENT 3.1. Natural occurrence 3.2. Man-made sources 4. ENVIRONMENTAL DISTRIBUTION AND TRANSFORMATION 4.1. Atmospheric transport and diffusion 4.2. Environmental absorption and transformation 5. ENVIRONMENTAL LEVELS AND EXPOSURES 5.1. Ambient air concentrations and exposures 5.2. Indoor concentrations and exposure 5.3. Occupational exposure 5.4. Carboxyhaemoglobin levels in the general population 6. METABOLISM 6.1. Endogenous carbon monoxide production 6.2. Absorption 6.3. Reactions with body tissues and fluids 6.4. Excretion 7. EFFECTS ON EXPERIMENTAL ANIMALS 7.1. Species differences 7.2. Cardiovascular system and blood 7.3. Central nervous system 7.4. Behavioural changes and work performance 7.5. Adaptation 7.6. Embryonal, fetal, neonatal, and teratogenic effects 7.7. Carcinogenicity and mutagenicity 7.8. Miscellaneous changes 7.9. Interactions 8. EFFECTS ON MAN 8.1. Healthy subjects 8.1.1. Behavioural changes 8.1.2. Work performance and exercise 8.1.3. Adaptation 8.1.4. Effects on the cardiovascular system and other effects 8.1.5. Carboxyhaemoglobin levels resulting from exposure to methane-derived halogenated hydrocarbons 8.1.6. Levels and effects of carboxyhaemoglobin resulting Page 2 of 105 Carbon monoxide (EHC 13, 1979) from smoking 8.1.7. Interactions 8.2. High-risk groups 8.2.1. Individuals with cardiovascular and chronic obstructive lung disease 8.2.2. Anaemic individuals 8.2.3. Embryo, fetus, neonate, and infants 8.2.4. Individuals living at high altitudes 8.3. Summary table 9. EVALUATION OF HEALTH RISKS 9.1. Introduction 9.2. Exposure 9.2.1. Assessment of exposure 9.2.2. Endogenous production 9.2.3. Outdoor environmental exposure 9.2.4. Indoor exposure 9.2.5. Exposures related to traffic 9.2.6. Occupational exposure 9.2.7. Tobacco smoking 9.2.8. Multiple exposures 9.3. Effects 9.3.1. Cardiovascular system 9.3.1.1 Development of atherosclerotic cardiovascular disease 9.3.1.2 Acute effects on existing heart illness 9.3.1.3 Acute effects on existing vascular disease 9.3.2. Nervous system 9.3.3. Work capacity 9.4. Recommended exposure limits 9.4.1. General population exposure 9.4.2. Working population exposure 9.4.3. Derived limits for carbon monoxide concentrations in air REFERENCES ANNEX 1 ANNEX 2 NOTE TO READERS OF THE CRITERIA DOCUMENTS While every effort has been made to present information in the criteria documents as accurately as possible without unduly delaying their publication, mistakes might have occurred and are likely to occur in the future. In the interest of all users of the environmental health criteria documents, readers are kindly requested to communicate any errors found to the Division of Environmental Health, World Health Organization, Geneva, Switzerland, in order that they may be included in corrigenda which will appear in subsequent volumes. In addition, experts in any particular field dealt with in the criteria documents are kindly requested to make available to the WHO Secretariat any important published information that may have inadvertently been omitted and which may change the evaluation of health risks from exposure to the environmental agent under examination, so that the information may be considered in the event of updating and re-evaluation of the conclusions contained in the criteria documents. Page 3 of 105 Carbon monoxide (EHC 13, 1979) WHO TASK GROUP ON ENVIRONMENTAL HEALTH CRITERIA FOR CARBON MONOXIDE Members Dr H. Buchwald, Assistant Deputy Minister, Alberta Department of Labour, Edmonton, Alberta, Canada (Chairman) Dr V.A. Cizikov, Central Institute for Advanced Medical Training, Moscow, USSR Dr E. Haak, Physiology Branch, Clinical Studies Division, Health Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA Dr P. Iordanidis, National Technical University of Athens, Athens, Greece Dr K. Ishikawa, Department of Public Health, School of Medicine, Chiba University, Chiba, Japan Dr V. Kodat, Hygiene Department, Ministry of Health of the Czech Socialist Republic, Prague, Czechoslovakia (Vice-Chairman) Dr K. Kurppa, Department of Occupational Medicine, Institute of Occupational Health, Helsinki, Finland Professor P.J. Lawther, Clinical Section, Medical Research Council Toxicology Unit, St Bartholomew's Hospital Medical College, London, England Mr I.R.C. McDonald, Chemistry Division, Department of Scientific & Industrial Research, Petone, New Zealand (Rapporteur) Dr G. Winneke, Institute for Air Hygiene & Silicosis Research, Düsseldorf, Federal Republic of Germany Representatives of other organizations Mr J. Janczak, Economic Commission for Europe, Geneva, Switzerland Dr D. Djordjevic, International Labour Office, Geneva, Switzerland Mr C. Satkunanthan, International Register of Potentially Toxic Chemicals of the United Nations Environment Programme, Geneva, Switzerland Observers Dr J.J. Vostal, Biomedical Science Department, General Motors Research Laboratories, Warren, MI, USA Secretariat Mrs B. Goelzer, Scientist, Office of Occupational Health, Division of Noncommunicable Disease, WHO, Geneva, Switzerland Dr Y. Hasegawa, Medical Officer, Control of Environmental Pollution & Hazards, Division of Environmental Health, WHO, Geneva, Switzerland Dr R. Horton, Senior Research Adviser, Health Effects Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA (Temporary Adviser) Page 4 of 105 Carbon monoxide (EHC 13, 1979) Dr J. Korneev, Scientist, Control of Environmental Pollution & Hazards, Division of Environmental Health, WHO, Geneva, Switzerland (Secretary) Dr H. de Koning, Scientist, Control of Environmental Pollution & Hazards, Division of Environmental Health, WHO, Geneva, Switzerland Dr M. Vandekar, Medical Officer, Pesticides Development & Safe Use, Division of Vector Biology & Control, WHO, Geneva, Switzerland Dr V.B. Vouk, Chief, Control of Environmental Pollution & Hazards, Division of Environmental Health, WHO, Geneva, Switzerland ENVIRONMENTAL HEALTH CRITERIA FOR CARBON MONOXIDE A WHO Task Group on Environmental Health Criteria for Carbon Monoxide met in Geneva from 11 to 17 October 1977. Dr V.B. Vouk, Chief, Control of Environmental Pollution and Hazards, opened the meeting on behalf of the Director-General. The Task Group reviewed and revised the second draft of the criteria document and made an evaluation of the health risks from exposure to carbon monoxide. The first and second drafts were prepared by Dr S.M. Horvath of the Institute of Environmental Studies, University of California, Santa Barbara, USA. The comments on which the second draft was based were received from the national focal points for the WHO Environmental Health Criteria Programme in Bulgaria, Canada, Czechoslovakia, France, Netherlands, Poland, USSR, and USA and from the International Labour Organisation (ILO), Geneva, the Food and Agriculture Organization of the United Nations (FAO), Rome, the United Nations Educational, Scientific and Cultural Organization (UNESCO), Paris, the United Nations Industrial Development Organization (UNIDO), Vienna, the Permanent Commission and International Association on Occupational Health, the Commission