International Environmental Health Criteria 82 Cypermethrin Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization WORLD HEALTH ORGANIZATION GENEVA 1989 Other titles available in the ENVIRONMENTAL HEALTH CRITERIA series include: 1. Mercury 2. Polychlorinated Biphenyls and Terphenyls 3. Lead 4. Oxides of Nitrogen 5. Nitrates, Nitrites, and N-Nitroso Compounds 6. Principles and Methods for Evaluating the Toxicity of Chemicals, Part 1 7. Photochemical Oxidants 8. Sulfur Oxides and Suspended Particulate Matter 9. DDT and its Derivatives 10. Carbon Disulfide 11. Mycotoxins 12. Noise 13. Carbon Monoxide 14. Ultraviolet Radiation 15. Tin and Organotin Compounds 16. Radiofrequency and Microwaves 17. Manganese 18. Arsenic 19. Hydrogen Sulfide 20. Selected Petroleum Products 21. Chlorine and Hydrogen Chloride 22. Ultrasound 23. Lasers and Optical Radiation 24. Titanium 25. Selected Radionuclides 26. Styrene 27. Guidelines on Studies in Environmental Epidemiology 28. Acrylonitrile 29. 2,4-Dichlorophenoxyacetic Acid (2,4-D) 30. Principles for Evaluating Health Risks to Progeny Associated with Exposure to Chemicals during Pregnancy 31. Tetrachloroethylene 32. Methylene Chloride 33. Epichlorohydrin 34. Chlordane 35. Extremely Low Frequency (ELF) Fields 36. Fluorine and Fluorides 37. Aquatic (Marine and Freshwater) Biotoxins 38. Heptachlor 39. Paraquat and Diquat 40. Endosulfan 41. Quintozene 42. Tecnazene 43. Chlordecone 44. Mirex continued on p. 156 This report contains the collective views of an in­ ternational group of experts and does not necessarily represent the decisions or the stated policy of the United Nations Environment Programme, the Interna­ tional Labour Organisation, or the World Health Organization Environmental Health Criteria 82 CYPERMETHRIN Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization World Health Organization Geneva, 1989 The International Programme on Chemical Safety (IPCS) is a joint venture of the United Nations Environment Programme, the International Labour Organisa­ tion, 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 develop­ ment 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 154282 9 ©World Health Organization 1989 Publications of the World Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Conven­ tion. 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 publica­ tion 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 Organiza­ tion 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. ISSN 0250-863X PRINTED IN FINLAND DHSS - VAMMALA - 5000 - 3 - CONTENTS ENVIRONMENTAL HEALTH CRITERIA FOR CYPERMETHRIN INTRODUCTION 12 l, SUMMARY 15 1.1 General 15 1.2 Environmental transport, distribution, and transformation , • , • , , , •• 15 1.3 Environmental levels and human exposure 16 1.4 Kinetics and metabolism ••• , • , , • 17 1.5 Effects on organisms in the environment 18 1.6 Effects on experimental animals and in vitro test systems 19 1.7 Mechanism of toxicity , 21 1.8 Effects on man 22 2. IDENTITY, PHYSICAL AND CHEMICAL PROPERTIES, ANALYTICAL METHODS 23 2.1 Identity 23 2.2 Physical and chemical properties 23 2,3 Analytical methods 25 3. SOURCES OF HUMAN AND ENVIRONMENTAL EXPOSURE 30 3.1 Industrial production 30 3.2 Use patterns ••••••• 30 4. ENVIRONMENTAL TRANSPORT, DISTRIBUTION, AND TRANSFORMATION • • • • • • • 31 4.1 Transport and distribution between media 31 4.1.1 Transport from soil to water , , 31 4.1.2 Transport within water bodies 32 4.2 Abiotic degradation , • , , , 33 4.2.1 Photodegradation 33 4.2.1.1 Basic studies 33 4.2.1.2 Photodegradation 33 4.3 Biological degradation in soil 35 4.3.1 Mechanism • • • • • 35 4.3.2 Degradation pathways (separate isomers) 36 4.3.3 Rates of degradation , ••• , • • • • • 37 - 4 - Page 4.3.3.1 Laboratory studies (separate isomers). 37 4.3.3.2 Field studies 39 4.4 Degradation in water and sediments 41 4.4.1 Laboratory studies • • • • 41 4.4.2 Field studies • • • • • • 42 4.5 Bioaccumulation and biomagnification 43 4.5.1 n-Octanol water partition coefficient 43 4.5.2 Bioaccumulation in fish • • • • • • 44 4.5.3 Bioaccumulation in aquatic invertebrates 46 5. ENVIRONMENTAL LEVELS AND HUMAN EXPOSURE 47 5.1 Environmental levels 47 5.1.1. Air 47 5.1.2 Water 47 5.1.3 Soil • 47 5.1.4 Food • 47 5.1.4.1 Residues in food commodities from treated crops 47 5.1.4.2 Residues in food of animal origin 48 5.2 General population exposure 49 5.3 Occupational exposure 49 6. KINETICS AND METABOLISM 50 6.1 Absorption, excretion, and distribution 50 6.1.1 Oral • . 50 6.1.1.1 Rat • 50 6.1.1.2 Mouse 52 6.1.1.3 Dog • 53 6.1.1.4 Cow • • 54 6.1.1.5 Sheep 54 6.1.1.6 Chicken 54 6.1.1.7 Man 55 6.1.2 Dermal • 56 6.1.2.1 Cow • • 56 6.1.2.2 Sheep 57 6.1.2.3 Man • 57 6.2 Metabolic transformation 58 6.2.1 In vitro studies • 58 6.2.2 In vivo studies 59 6.2.3 Metabolism of the glucoside conjugate of 3-phenoxybenzoic acid 60 6.3 Metabolism in plants 60 6.4 Metabolism in fish 65 - 5 - Page 7. EFFECTS ON ORGANISMS IN THE ENVIRONMENT 66 7.1 Microorganisms 66 7.2 Aquatic organisms 67 7.2.1 Fish • • 67 7.2.1.1 Acute toxicity 67 7.2.1.2 Long-term toxicity 70 7.2.2 Invertebrates • • • • • • • 71 7.2.2.1 Acute toxicity 71 7.2.2.2 Long-term toxicity 71 7.2.3 Field studies • • • • • • • 71 7.2.3.1 Deliberate overspraying 71 7.2.3.2 Monitoring of drift from ground and aerial applications 75 7.3 Terrestrial organisms • • • • • 77 7.3.1 Laboratory studies • • • • 77 7.3.1.1 Acute toxicity 77 7.3.1.2 Short-term toxicity 77 7.3.2 Field studies • • • • • • • 80 7.3.2.1 Applications for tsetse fly control in Nigeria 80 7.3.2.2 Honey bees • • • • • • 81 7.3.2.3 Soil fauna • • • • • • 83 7.3.2.4 Foliar predators and parasites 84 8. EFFECTS ON EXPERIMENTAL ANIMALS AND IN VITRO TEST SYSTEMS • • • • • 85 8.1 Single exposures 85 8.1.1 Oral ••• 85 8.1.2 Dermal 85 8.1.3 Intraperitoneal 85 8.1.4 Inhalation ••• 87 8.1.5 Skin and eye irritation 88 8.1.6 Sensitization 88 8.2 Short-term exposures 88 8.2.1 Oral •• 88 8.2.1.1 Rat 88 8.2.1.2 Dog 90 8.2.2 Dermal • 90 8.2.2.1 Rabbit 90 8.2.3 Intravenous 91 8.2.3.1 Rat 91 8.3 Long-term exposures 91 8.3.1 Rat 91 8.3.2 Mouse 92 8.3.3 Dog 92 - 6 - Page 8.4 Special studies • • • • • • • • • • • • 94 8.4.1 Synergism/potentiation studies • 94 8.4.1.1 Organophosphate mixture 94 8.4.1.2 Organochlorine mixture 94 8.4.2 Neurotoxicity ••••••••• 94 8.4.2.1 Characterization of the neurotoxic effects 94 8.4.2.2 Neuropathological studies 95 8.4.2.3 Biochemical and electro­ physiological studies 96 8.4.2.4 Appraisal ••• 99 8.4.3 Immunosuppressive action 99 8.5 Reproduction, embryotoxicity, and teratogenicity • • • • 100 8.5.1 Reproduction • • ••• 100 8.5.2 Embryotoxicity and teratogenicity • 101 8.5.2.1 Rat • • •••• 101 8.5.2.2 Rabbit ••••• • 101 8.6 Mutagenicity and related end-points 102 8.6.1 In vitro studies •••• 102 8.6.1.1 Microorganisms 102 8.6.1.2 Mammalian cells 102 8.6.2 In vivo studies 102 8.6.2.1 Host-mediated assay 102 8.6.2.2 Dominant lethal assay 102 8.6.2.3 Bone marrow chromosome study • 103 8.6.2.4 Micronucleus test • 103 8.7 Carcinogenicity 104 8.7.1 Oral •• 104 8. 7 .1.1 Rat • • 104 8. 7 .1. 2 Mouse 104 8.8 Mechanisms of toxicity - mode of action 105 9. EFFECTS ON MAN • • 107 9.1 General population exposure 107 9.1.1 Acute toxicity~ poisoning incidents 107 9.1.2 Controlled human studies 107 9.1.3 Epidemiological studies •••••• 107 9.2 Occupational exposure •••••••••• • 107 9.2.1 Acute toxicity~ poisoning incidents 107 9.2.2 Effects of short- and long-term exposure 107 - 7 - Page 10. EVALUATION OF HEALTH RISKS FOR MAN AND EFFECTS ON THE ENVIRONMENT 111 10.1 Evaluation 111 10.2 Conclusions 112 11. RECOMMENDATIONS 114 12.