THE ENVIRONMENTAL

(1)

(2)

Acrolein (No. 127, 1991) Acrylamide (No 49, 1985) Acrylonitrile (No. 28, 1983)

Aged population, principles for evaluating the effects of chemicals (No. 144, 1992) Aldicarb (No. 121, 1991)

Aldrin and dieldrin (No. 91, 1989) Allethrlns (No. 87, 1989) Amitrole (No. 158, 1994) Ammonia (No. 54, 1986) Arsenic (No. 18, 1981)

Asbestos and other natural mineral fibres (No. 53, 1986)

Barium (No. 107, 1990) Benomyl (No 148, 1993) Benzene (No. 150, 1993) Beryllium (No. 106, 1990)

Biomarkers and risk assessment· concepts and principles (No. 155, 1993)

Biotoxins, aquatic (marine and freshwater) (No. 37, 1984)

Brominated dlphenylethers (No. 162, 1994) Butanols - four Isomers (No. 65, 1987) Cadmium (No. 134, 1992)

Cadmium - environmental aspects (No. 135, 1992) Camphechlor (No. 45, 1984)

Carbamate pesticides. a general introduction (No. 64, 1986)

Carbaryl (No. 153, 1994) Carbendazim (No. 149, 1993) Carbon disulfide (No. 10, 1979) Carbon monoxide (No 13, 1979)

Carcinogens, summary report on the evaluation of short-term in vitro tests (No. 47, 1985) Carcinogens, summary report on the evaluation

of short-term in vivo tests (No 109, 1990) Chlordane (No. 34, 1984)

Chlordecone (No. 43, 1984)

Chlorine and hydrogen chloride (No 21, 1982) Chlorobenzenes other than hexachlorobenzene

(No. 128, 1991)

Chloronuorocarbons, fully halogenated (No. 113, 1990)

Chloronuorocarbons, partially halogenated (ethane derivatives) (No. 139, 1992) (methane derivatives) (No. 126, 1991) Chlorophenols (No 93, 1989) Chromium (No 61, 1988) Cyhalothrin (No 99, 1990) Cypermethrin (No. 82, 1989) Cypermethrin, alpha- (No. 142, 1992) DDT and Its derivatives (No. 9, 1979) DDT and its derivatives - environmental aspects

(No. 83, 1989)

Deltamethrin (No. 97, 1990) Diaminotoluenes (No. 74, 1987)

2,4-Dichlorophenoxyacetic acid (2,4-D) (No 29, 1984)

2,4-Dichlorophenoxyacetic acid - environmental aspects (No. 84, 1989)

1 ,3-Dichloropropene, 1 ,2-dichloropropane and mixtures (No. 146, 1993)

Dichlorvos (No 79, 1988)

Diethylhexyl phthalate (No. 131, 1992) Dimethoate (No. 90, 1989)

Dimethylformamide (No. 114, 1991) Dimethyl sulfate (No. 48, 1985)

Diseases of suspected chemical etiology and their prevention, principles of studies on (No. 72, 1987)

Dithiocarbamate pesticides, ethylenethiourea, and propylenethiourea: a general introduction (No. 78, 1988)

Electromagnetic fields (No. 137, 1992) Endosulfan (No. 40, 1984)

Endrin (No 130, 1992)

Environmental epidemiology, guidelines on studies in (No. 27, 1983)

Epichlorohydrin (No 33, 1984) Ethylene oxide (No 55, 1985)

Extremely low frequency (ELF) fields (No 35, 1984)

Fenitrothion (No 133, 1992) Fenvalerate (No 95, 1990) Fluorine and nuorides (No. 36, 1984) Food additives and contaminants in food,

principles for the safety assessment of (No 70, 1987)

Formaldehyde (No. 89, 1989) Genetic effects In human populations,

guidelines for the study of (No. 46, 1985) Glyphosate (No. 159, 1994)

Heptachlor (No 38, 1984) Hexachlorobutadiene (No 156, 1994) Alpha- and beta-hexachlorocyclohexanes

(No. 123, 1991)

Hexachlorocyclopentadiene (No. 120, 1991) n-Hexane (No. 122, 1991)

Hydrazine (No. 68, 1987) Hydrogen sulfide (No 19, 1981) Hydroqulnone (No. 157, 1994)

Infancy and ear1y childhood, principles for evaluating health risks from chemicals during (No. 59, 1986)

lsobenzan (No. 129, 1991) Kelevan (No. 66, 1986)

Lasers and optical radiation (No 23, 1982) Lead (No. 3, 1977)'

Lead - environmental aspects (No. 85, 1989) Lindane (No. 124, 1991)

Magnetic fields (No. 69, 1987) Man-made mineral fibres (No. 77, 1988)

(3)

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 Interna- tional Labour Organisation, or the World Health Organization.

Environmental Health Criteria 162

BROMINATED DIPHENYL ETHERS

First draft prepared by Dr G.J. van Esch, B1lthoven, Netherlands

Published under the joint sponsorship of the United Nations Environment Programme, the International Labour Organisation, and the World Health Organization

World Health Organization Geneva, 1994

(4)

evaluations of the effects of chermcals on human health and the quality of the envuonment.

Supporting activities include the development of epidermolog1cal, expenmentallaboratory, and risk-assessment methods that could produce internationally comparable results, and the development of manpower in the field of toxicology. Other activ1ties carried out by the IPCS include the development of know-how for copmg with chemical accidents, coordination of laboratory testing and epidemiological studies, and promotion of research on the mechanisms of the biological action of chemicals.

WHO Library Cataloguing in Publication Data Brominated diphenylethers.

(Environmental health critena ; 162)

l.Phenyl ethers - adverse effects 2.Environmental exposure 3. Occupational exposure l.Senes

ISBN 92 4 157162 4 ISSN 0250-863X

(NLM Classification: QD 34l.E7)

The World Health Orgamzatwn welcomes requests for perrmsswn to reproduce or translate its publications, in part or in full. Applications and enquiries should be addressed to the Office of Pubhcatwns, World Health Organization, Geneva, Switzerland, wh1ch will be glad to prov1de the latest information on any changes made to the text, plans for new editions, and reprints and translatiOns already ava1lable.

©World Health Organization 1994

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 Secretanat of the World Health Organization concerning the legal status of any country, terntory, c1ty or area or of 1ts authonties, 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 smlilar nature that are not mentioned. Errors and ormssions excepted, the names of propnetary products are distinguished by initial capital letters.

PRINTED IN FINLAND

(5)

CONTENTS

Page GLOSSARY 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 18 BROMINATED DIPHENYL ETHERS - GENERAL

INTRODUCTION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o 0 0 0 0 0 0 0 0 0 0 25

1. GENERAL REMARKS 27

20 GENERAL INFORMATION ON BROMINATED

DIPHENYL ETHERS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 31 2 ol Analytical methods 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 31 202 Production levels and processes 0 0 0 0 0 0 0 0 0 0 0 31 203 Resins, polymers and substrates in

which PBDE are used 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 34 30 FORMATION OF BROMINATED DIBENZOFURANS

AND DIBENZODIOXINS FROM POL YBROMINATED DIPHENYL ETHERS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 39 3 ol General 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 39 302 Additional data on pyrolysis of

non-specified PBDE and/or polymers

containing non-specified PBDE 0 0 0 0 0 0 0 0 0 0 0 0 41 40 WORKPLACE EXPOSURE STUDIES 0 0 0 0 0 0 0 0 0 0 44 401 Exposure to PBDE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 44 402 Exposure to PBDF/PBDD 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 44

50 EXPOSURE OF THE GENERAL POPULATION 0 0 0 46 5 ol General population 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 46 502 Possible exposure to PBDE and PBDF/PBDD 0 0 0 46 50201 Television sets 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 46 50202 Fire tests and fire accidents 0 0 0 0 0 0 0 0 0 0 47 60 ENVIRONMENTAL POLLUTION BY PBDE 0 0 0 0 0 51 601 Ultimate fate following use 0 0 0 0 0 0 0 0 0 0 0 0 0 0 51 602 Air 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 52 3

(6)

6.3 6.4 6.5 6.6 6.7 6.8

Soil . . . . Water

Sediments and sewage sludge . . . . Aquatic vertebrates . . . . Aquatic mammals . . . . Terrestrial vertebrates . . . . 6.8.1 Birds . . . . 6.8.2 Humans

52 52 53 53 54 54 55 55

DECABROMODIPHENYL ETHER . . . . 57

1. SUMMARY, EVALUATION, CONCLUSIONS, AND RECOMMENDATIONS . . . 59

1.1 Summary and evaluation . . . 59

1.1.1 Identity, physical and chemical properties . . . 59

1.1.2 Production and uses . . . 59

1.1.3 Environmental transport, distribution, and transformation . . . 59

1.1.4 Environmental levels and human exposure . 60 1.1.5 Kinetics and metabolism in laboratory animals and humans . . . 61

1.1.6 Effects on laboratory mammals and in vitro test systems . . . 62

1.1. 7 Effects on humans . . . 63

1.1. 8 Effects on other organisms in the laboratory and field . . . 63

1.2 Conclusions . . . 63

1.2.1 DeBDE . . . 63

1.2.2 Breakdown products . . . 64

1. 3 Recommendations . . . 64

1.3.1 General . . . 64

1.3.2 Further studies . . . 65

2. IDENTITY, PHYSICAL AND CHEMICAL PROPERTIES, ANALYTICAL METHODS . . . 66

2.1 Identity . . . 66

2.1.1 Pure substance . . . 66

(7)

2.3 Analytical methods . . . 70

3. SOURCES OF HUMAN AND ENVIRONMENTAL EXPOSURE . . . 71

3 .1 Natural occurrence . . . 71

3.2 Anthropogenic sources . . . 71

3.2.1 Production levels and processes . . . 71

3.2.2 Uses . . . 72

4. ENVIRONMENTAL TRANSPORT, DISTRIBUTION, AND TRANSFORMATION . . . 73

4.1 Transport and distribution between media . . . 73

4.1.1 Extraction from polymers . . . 73

4.2 Biotransformation . . . 73

4.3 Abiotic degradation . . . 73

4.3.1 Photodegradation . . . 73

4.3.2 Pyrolysis . . . 75

4.3.3 Combustion of DeBOE and polymers containing DeBOE . . . 76

4.3.3.1 Pyrolysis studies . . . 76

4.3.3.2 Workplace exposure studies . . . . 93

4.4 Ultimate fate following use . . . 10I 4.4.I General . . . 101

4.4.2 Exposure of the general population 102 4.5 Fire accident . . . 102

4.6 Simulated fire conditions . . . 103

4.7 Bioaccumulation . . . I04 5. ENVIRONMENTAL LEVELS AND HUMAN EXPOSURE . . . 105

5 .I Environmental levels . . . I 05 5.1.1 Air . . . 105

5.1.2 Water . . . 105

5.1.3 Aquatic sediments . . . 105

5 .1. 4 Aquatic and terrestrial organisms . . . 106

5.2 Exposure of humans . . . 107

5.2.1 Occurrence of DeBOE in human tissues 107 5.2.2 Occupational exposure . . . 107

5

(8)

60 KINETICS AND METABOLISM IN LABORATORY ANIMALS AND HUMANS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 109 601 Absorption and elimination 0 0 0 0 0 0 0 0 0 0 0 0 0 0 109 602 Distribution 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 110 603 Retention and turnover 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 111 70 EFFECTS ON LABORATORY MAMMALS AND

IN Vl1RO TEST SYSTEMS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 112 7 01 Single exposure 0 0 0 0 0 . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 112 7 0 101 Oral: Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 112 701.2 Dermal: Rabbit 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 112 701.31nhalation:Rat o o o o o o o o o o o o o o o o o o 112 702 Short-term exposure 0 0 0 0 0 0 0 0 0 0 0 0 0 0 . 0 0 0 113 70201 Oral 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 113 70201.1 Mouse 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 113 7 0201.2 Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 113 70202 Inhalation 0 0 0 0 0 . 0 . 0 0 0 0 0 0 0 0 0 0 0 0 0 115 702.201 Rat 0 . 0 0 0 0 0 0 0 0 0 0 0 0 .. 0 0 0 115 7 0 3 Long-term exposure 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 . 0 0 115 7 0301 Oral 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 115 70301.1 Mouse 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 115 70301.2 Rat 0 0 0 . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 116 7.4 Skin and eye irritation; sensitization 0 0 0 0 0 0 0 0 0 116 7.401 Skin irritation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 116 7.402 Eye irritation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 116 7.4 0 3 Sensitization 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 117 7.404 Chloracnegenic activity 0 0 0 0 0 0 0 0 0 0 0 0 0 117 7 05 Reproductive toxicity, embryotoxicity, and

teratogenicity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 117 7 05 01 Reproductive toxicity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 117 7 05 02 Teratogenicity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 118 7 06 Mutagenicity and related end-points 0 0 0 0 0 0 0 0 0 119 70601 Mutation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 119 70602 Chromosomal effects 0 0 0 0 0 0 0 0 0 0 0 0 0 0 119 7 0 7 Carcinogenicity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 120 7 0 7 0 1 Oral 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 . 0 120 7070101 Mouse 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 120 7 0 7 01.2 Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 120

(9)

7.8.2 Miscellaneous . . . 122

7.8.3 Toxicity of soot, char, and other waste products from combustion of DeBDE-containing polymers . . . 123

7.8.3.1 Acuteoraltoxicity . . . 123

7.8.3.2 Skin irritation and comedogenicity 123 7.8.3.3 Eye irritation . . . 125

8. EFFECTS ON HUMANS . . . 126

8.1 General population exposure . . . 126

8.2 Occupational exposure . . . 126

8.2.1 Skin sensitization . . . 126

8.2.2 Neurotoxicity . . . 126

8.2.3 Epidemiological studies . . . 127

9. EFFECTS ON OTHER ORGANISMS IN THE LABORATORY AND FIELD . . . 129

10. PREVIOUS EVALUATIONS BY INTERNATIONAL BODIES . . . 130

NONABROMODIPHENYL ETHER 131 1. SUMMARY, EVALUATION, CONCLUSIONS AND RECOMMENDATIONS . . . 133

2. 1.1 Summary and evaluation . . . 133

1.2 Recommendations . . . 133

IDENTITY, PHYSICAL AND CHEMICAL PROPERTIES, ANALYTICAL METHODS 134 2.1 Identity . . . 134

2.2 Physical and chemical properties . . . 135

3.1 Natural occurrence . . . 136

3.2.2 Uses . . . 136

7

(10)

OCTABROMODIPHENYL ETHER 137 1. SUMMARY, EVALUATION, CONCLUSIONS

20

AND RECOMMENDATIONS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 139 1.1 Summary and evaluation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 139 1.1.1 Identity, physical and chemical properties 139 1.1.2 Production and uses 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 139 1.1.3 Environmental transport, distribution, and

transformation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 139 1.1.4 Environmental levels and human exposure 140 10105 Kinetics and metabolism in laboratory

animals and humans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 140 10106 Effects on laboratory mammals and in vitro

test systems 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 141 1.1. 7 Effects on humans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 142 1010 8 Effects on other organisms in the

laboratory and field 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 142 1.2 Conclusions 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 142 1.201 OBDE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 142 1.202 Breakdown products 0 0 0 0 0 0 0 0 0 0 • 0 0 0 143 1.3 Recommendations 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 143 1.301 General 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 143 1.302 Further studies 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 144 IDENTITY, PHYSICAL AND CHEMICAL

PROPERTIES, ANALYTICAL METHODS 145

201 Identity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 145 201.1 Technical product 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 146 203 Physical and chemical properties 0 0 0 0 0 0 0 0 0 0 0 146 203 Analytical methods 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 147 30 SOURCES OF HUMAN AND ENVIRONMENTAL

EXPOSURE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 148 3 01 Natural occurrence 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 148 302 Anthropogenic sources 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 148 30201 Production levels and processes 0 0 0 0 0 0 0 148 30202 Uses 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 . . . 0 0 0 . . 148

(11)

40 ENVIRONMENTAL TRANSPORT, DISTRIBUTION, AND TRANSFORMATION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 149 401 Biotransformtion 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 149 4o2 Abiotic degradation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 149 4o2o1 Pyrolysis of octabromodiphenyl ether 0 0 0 0 149 40202 Pyrolysis studies with polymers containing

octabromodiphenyl ether 0 0 0 0 0 0 0 0 0 0 0 0 149 40203 Behaviour of octabromodiphenyl ether

during processing 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 150 403 Bioaccumulation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 151 4.4 Ultimate fate following use 0 0 0 0 0 0 0 0 0 0 0 0 0 0 151 50 ENVIRONMENTAL LEVELS AND HUMAN

EXPOSURE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 152 501 Environmental levels 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 152 501.1 Water 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 152 501.2 Aquatic sediments 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 152 501.3 Aquatic and terrestrial organisms 0 0 0 0 0 0 152 502 Exposure of the general population 0 0 0 0 0 0 0 0 0 152 503 Occupational exposure during manufacture,

formulation or use 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 153 60 EFFECTS ON LABORATORY MAMMALS AND

IN VIIRO TEST SYSTEMS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 154 601 Single exposure

601.1 Oral: Rat

601.2 Dermal: Rabbit 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 601.3 Inhalation: Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 602 Short-term exposure 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 60201 Oral: Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 60202 Inhalation: Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 603 Long-term exposure 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6.4 Skin and eye irritation; sensitization 0 0 0 0 0 0 0 0 0 6.401 Skin irritation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 6.402 Eye irritation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 605 Teratogenicity, reproductive toxicity,

and embryotoxicity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 605 01 Teratogenicity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 60501.1 Oral: Rat 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 60501.2 Oral: Rabbit 0 0 0 0 0 0 0 0 0 0 0 0 0 0

154 154 154 154 155 155 157 158 158 158 159 159 159 159 160

9

(12)

6.6 Mutagenicity and related end-points . . . . 6.6.1 DNA damage . . . . 6.6.2 Mutation . . . . 6.6.3 Chromosomal effects . . . . . . 6.7 Carcinogenicity . . . . 6.8 Other special studies . . . . 6.8.1 Liver . . . . 6.9 Appraisal . . . .

161 161 161 161 161 162 162 163

HEPT ABROMODIPHENYL ETHER 165

1. SUMMARY, EVALUATION, CONCLUSIONS

AND RECOMMENDATIONS . . . 167

2. IDENTITY, PHYSICAL AND CHEMICAL PROPERTIES, AND ANALYTICAL METHODS . . . 168

2.1 Identity . . . 168

3. 2 Anthropogenic sources . . . 170

3.2.1 Production levels and proc,~sses . . . 170

4. ENVIRONMENTAL TRANSPORT, JDISTRIBUTION, AND TRANSFORMATION . . . 171

5. ENVIRONMENTAL LEVELS AND HUMAN EXPOSURE . . . 172

6. EFFECTS ON LABORATORY MAMMALS AND IN VITRO TEST SYSTEMS . . . 173

6.1 Single exposure . . . .. . . 173

6.2 Skin and eye irritation; sensitization . . . 173

HEXABROMODIPHENYL ETHER . . . . 175 1. SUMMARY, EVALUATION, CONCLUSIONS AND

(13)

20 IDENTITY, PHYSICAL AND CHEMICAL

PROPERTIES, ANALYTICAL METHODS 0 0 0 0 0 0 178 201 Identity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 178 201.1 Technical product 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 178 202 Physical and chemical properties 0 0 0 0 0 0 0 0 0 0 0 179 203 Analytical methods 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 179 30 SOURCES OF HUMAN AND ENVIRONMENTAL

EXPOSURE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 180 3 01 Natural occurrence 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 180 302 Anthropogenic sources 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 180 3o3 Uses 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 180 40 ENVIRONMENTAL TRANSPORT, DISTRIBUTION,

AND TRANSFORMATION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 181 50 ENVIRONMENTAL LEVELS AND HUMAN

EXPOSURE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 182 501 Levels in the environment 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 182 5 01 0 1 Water 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 182 501.2 Aquatic sediments 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 182 501.3 Aquatic and terrestrial organisms 0 0 0 0 0 0 182 502 General population exposure 0 0 0 0 0 0 0 0 0 0 0 0 0 183 60 KINETICS AND METABOLISM IN LABORATORY

ANIMALS AND HUMANS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 184 PENTABROMODIPHENYL ETHER 0 0 0 0 0 0 0 0 0 0 0 0 0 185

1. SUMMARY, EVALUATION, CONCLUSIONS AND RECOMMENDATIONS 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 187 1.1 Summary and evaluation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 187 1.1.1 Identity, physical and chemical properties 0 187 1.1.2 Production and uses 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 187 10103 Environmental transport, distribution

and transformation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 187 1.1.4 Environmental levels and human exposure 0 188 1.1.5 Kinetics and metabolism in laboratory animals

and humans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 189 10106 Effects on laboratory mammals and in vitro

test systems 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 189

11

(14)

20

1010 7 Effects on humans 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 189 1010 8 Effects on other organisms in the laboratory

and field 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 190 1.2 Conclusions 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ô 0 0 0 0 0 0 190 1.201 PeBDE 0 0 0 0 0 0 0 0 ô ô ô ô 0 0 0 0 0 0 0 0 ô ô ô 190 1.202 Breakdown products 0 0 0 0 0 0 0 0 0 0 0 0 0 0 190 1.3 Recommendations 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 191 1.301 General 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 191 1.302 Further studies 0 0 0 0 0 0 0 0 0 ô 0 0 0 0 0 0 0 0 191 IDENTITY, PHYSICAL AND CHEMICAL

PROPERTIES, ANALYTICAL METHODS 193

201 Identity 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 193 201.1 Technical product 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 194 202 Physical and chemical properties 0 0 0 0 0 0 0 0 0 0 0 195 203 Analytical methods 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 195 30 SOURCES OF HUMAN AND ENVIRONMENTAL

EXPOSURE 0 0 0 0 0 0 0 0 0 0 0 0 0 ^o 0 0 0 0 0 0 0 0 0 0 0 ^o 197 3 01 Natural occurrence 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 197 302 Anthropogenic sources 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 197 30201 Production levels and processes 0 0 0 0 0 0 0 197 30202 Uses 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 197 40 ENVIRONMENTAL TRANSPORT, DISTRIBUTION,

AND TRANSFORMATION 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 198 401 Pyrolysis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 198 402 Workplace exposure studies 0 0 0 0 0 0 0 0 0 0 0 0 0 0 198 403 Bioaccumulation 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 198 4.4 Ultimate fate following use 0 0 0 0 0 0 0 0 0 0 0 0 0 0 199

50 ENVIRONMENTAL LEVELS AND HUMAN

EXPOSURE 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 200 5 01 Levels in the environment 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

5 01.1 Sediment and sewage sludge 0 0 0 0 0 0 0 0 0 501.2 Fish and shellfish 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 501.3 Aquatic mammals 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 501.4 Terrestrial mammals 0 0 0 0 0 0 0 0 0 0 0 0 0 0 501.5 Birds 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

200 200 201 202 202 202

(15)

6. KINETICS AND METABOLISM IN LABORATORY

ANIMALS AND HUMANS . . . 205

7. EFFECTS ON LABORATORY MAMMALS AND IN V/1RO TEST SYSTEMS . . . . 206

7.1 Single exposures . . . 206

7. 1. 1 Oral . . . 206

7 .1.2 Dermal . . . 206

7. 1. 3 Inhalation . . . 207

7.2 Short-term exposure . . . 207

7.3 Long-term exposure . . . 209

7.4 Skin and eye irritation; sensitization . . . 209

7 .4.1 Skin irritation . . . 209

7 .4.2 Eye irritation . . . 209

7.5 Reproductive toxicity, embryotoxicity and teratogenicity . . . 209

7.6 Mutagenicity and related end-points . . . 210

7.7 Carcinogenicity . . . 210

7.8 Other special studies . . . 210

TETRABROMODIPHENYL ETHER . . . 213

1. SUMMARY, EVALUATION, CONCLUSIONS AND RECOMMENDATIONS . . . 215

1.1.1 Identity, physical and chemical properties 215 1.1.2 Production and uses . . . 215

1.1. 4 Environmental levels and human exposure . 216 1.1.5 Effects on laboratory mammals and in vitro test systems . . ^c ^• ^• ^• ^• ^• ^• ^• ^• ^• ^• ^• ^• 217 1.1.6 Kinetics and metabolism in laboratory animals and humans . . . 217

1.1.7 Effects on humans . . . 217

1.1.8 Effects on other organisms in the laboratory and field . . . 217

1.2 Conclusions . . . 218

1.2.1 TeBDE . . . 218

1.2.2 Breakdown products . . . 218

1.3 Recommendations . . . 219 13

(16)

2.

1.3.1 General . . . 219

1.3.2 Further studies . . . 219

IDENTITY, PHYSICAL AND CHEMICAL PROPERTIES, ANALYTICAL METHODS 221 2.1 Identity . . . 221

3.2.2 Uses . . . 223

4.1 Pyrolysis . . . 224

4.2 Ultimate fate following use . . . 224

5.1 Environmental levels . . . 225

5 .1.1 Soil and sediment . . . 225

5.1.2 Fish and shellfish . . . 226

5.1.3 Birds . . . 227

5.1.4 Aquatic mammals . . . 228

5.1.5 Terrestrial mammals . . . 229

5.2 General population exposure . . . 229

6. KINETICS AND METABOLISM IN LABORATORY ANIMALS AND HUMANS 230 TRIBROMODIPHENYL ETHER 231 1. SUMMARY, EVALUATION, CONCLUSIONS AND RECOMMENDATIONS . . . 233

(17)

2. IDENTITY, PHYSICAL AND CHEMICAL

PROPERTIES, ANALYTICAL METHODS . . . 234

2.1 Identity . . . 234

4.1.1 Birds . . . 237

DIBROMODIPHENYL ETHER . . . 239

1. 2 Recommendations . . . 241

2.1 Identity . . . 242

5.1.1 Water . . . 246

5.1.2 Soil/sediment . . . 246

15

(18)

5.1.3 Birds . . . . 5.2 General population exposure

246 246 6. EFFECTS ON LABORATORY MAMMALS AND

IN VI1RO TEST SYSTEMS . . . . 247

6.1 Single exposure . . . 247

6.2 Other special studies . . . 247

6.2.1 Liver . . . 247

MONOBROMODIPHENYL ETHER . . . . 249

1.1.1 Physical and chemical properties . . . 251

1.1.2 Production and uses . . . 251

1.1.4 Environmental levels and human exposure . 252 1.1.5 Kinetics and metabolism in laboratory animals :md humans . . . 252

1.1.6 Effects on laboratory mammals and in vitro test systems . . . 252

1.1. 7 Effects on humans . . . 252

1.1. 8 Effects on other organisms in the laboratory and field . . . 252

1.2 Conclusions and recommendations . . . 252

2.1 Identity . . . 254

(19)

4. ENVIRONMENTAL TRANSPORT, DISTRIBUTION,

AND TRANSFORMATION . . . 257

4.1 Transport and distribution between media . . . 257

4.2 Biotransformation . . . 257

4.2.1 Biodegradation . . . 257

5 .1. 1 Water . . . 259

5 .1.2 Soil/Sediment . . . 259

5 .1. 3 Aquatic organisms . . . 260

6. EFFECTS ON LABORATORY MAMMALS AND IN VIIRO TEST SYSTEMS . . . . 261

6.1 Reproductive toxicity, embryotoxicity, teratogenicity . . . 261

6.2 Carcinogenicity 261 7. EFFECTS ON OTHER ORGANISMS IN THE LABORATORY AND FIELD . . . 263

REFERENCES . . . 265

RESUME ET EVALUATION, CONCLUSIONS ET RECOMMANDA TIONS . . . 283

RESUMEN, EVALUACION, CONCLUSIONES Y RECOMENDACIONES . . . 317

17

(20)

PBDE MBDE DiBDE TrBDE TeBDE PeBDE HxBDE HpBDE OBDE NBDE DeBDE PBDF TeBDF PeBDF HxBDF HpBDF PBDD TeBDD PeBDD HxBDD HpBDD PBBz PBP PBN PBB PCB THP

ABS BASF BFRIP

polybrominated diphenyl ethers monobromodiphenyl ethers dibromodiphenyl ethers tribromodiphenyl ethers tetrabromodiphenyl ethers pentabromodiphenyl ethers hexabromodiphenyl ethers heptabromodiphenyl ethers octabromodiphenyl ethers nonabromodiphenyl ethers decabromodiphenyl ethers polybrominated dibenzofurans tetrabromodibenzofurans pentabromodibenzofurans hexabromodibenzofurans heptabromodibenzofurans polybrominated dibenzodioxins tetrabromodibenzodioxins pentabromodibenzodioxins hexabromodibenzodioxins heptabromodibenzodioxins polybrominated benzenes polybrominated phenols pol ybrominated naphthalenes polybrominated biphenyls polychlorinated biphenyls

Tetrakis(hydroxymethyl)phosphonium salts

acrylonitrile-butadiene-styrene Badische Anilin und Soda Fabrik

Brominated Flame Retardant Industry Panel

(21)

CEFIC DTA EBFRIP EEC ER FY GC/ECD GC/MS HIPS HPLC HRGC/MS IG

NCI NHATS NIOSH PA PAN PBT PE PET pp PR PS PUR PVC SIM TGA UPE US EPA US NTP XPE

Conseil Europeen de l'Industrie Chimique (European Chemical Industry Council)

differential thermal analysis

European Brominated Flame Retardant Industry Panel European Economic Community

epoxy resin Fiscal Year

gas chromatography/electron capture detector gas chromatography/mass spectrometry high impact polystyrene

high pressure liquid chromatography high resolution gas chromatography/mass spectrometry

ignition loss

negative chemical ionization

National Human Adipose Tissue Survey

National Institute of Occupational Safety and Health polyamide

polyacrylonitrile

polybutylene terephthalate polyethylene

polyethylene terephthalate polypropylene

phenolic resin polystyrene polyurethane polyvinylchloride selective ion monitoring thermal gravimetric analysis unsaturated (Thermoset) polyesters

United States Environmental Protection Agency United States National Toxicology Program cross-linked polyethylene

19

(22)

Members

Dr L.A. Albert, Consultores Ambientales Asociados, S.C., Xalapa, Veracruz, Mexico (Vice-Chairman)

DrS. Dobson, Institute of Terrestrial Ecology, Monks Wood Experimental Station, Cambridgeshire, United Kingdom Professor B. Jansson, Institute of Applied Environmental Research, Stockholm University, Solna, Sweden

Dr J. Kielhorn, Fraunhofer Institute for Toxicology and Aerosol Research, Hanover, Germany

Dr M. Luotamo, Finnish Institute of Occupational Health, Helsinki, Finland

Professor Wai-On Phoon, Worksafe Australia, and University of Sydney, Sydney, Australia (Chairman)

Mr J. Rea, Department of Environment, London, United Kingdom DrS. Sleight, Department of Pathology, Michigan State

University, East Lansing, USA Observers

Dr M.L. Hardy, Health and Environment, Ethyl Corporation, Baton Rouge, USA

Dr D.L. McAllister, Quality Assurance and Research Services, Great Lakes Chemical Corporation, West Lafayette, Indiana, USA

(23)

Secretariat

Dr K.W. Jager, International Programme on Chemical Safety, World Health Organization, Geneva, Switzerland (Secretary) Dr G.J. van Esch, Bilthoven, The Netherlands (Rapporteur)

21

(24)

Every effort has been made to present information in the criteria documents as accurately as possible without unduly delaying their publication. In the interest of all users of the environmental health criteria documents, readers are kindly requested to communicate any errors that may have occurred to the Director of the International Programme on Chemical Safety, World Health Organization, Geneva, Switzerland, in order that they may be included in corrigenda, which will appear in subsequent volumes.

* * *

A detailed data profile and a legal file can be obtained from the International Register of Potentially Toxic Chemicals, Case Postale 356, 1219 Chatelaine, Geneva, Switzerland (Telephone No.

9799111).

* * *

This publication was made possible by grant number 5 U01 ES02617-14 from the National Institute of Environmental Health Sciences, National Institutes of Health, USA.

NOTE: The proprietary information contained in this document cannot replace documentation for registration purposes, because the latter has to be closely linked to the source, the manufacturing route, and the purity/impurities of the substance to be registered. The data should be used in accordance with paragraphs 82-84 and recommendations paragraph 90 of the Second F AO Government Consultation (1982).

(25)

ENVIRONMENTAL HEALTH CRITERIA FOR BROMINATED DIPHENYL ETHERS

A WHO Task Group on Environmental Health Criteria for Brominated Diphenyl Ethers met at the World Health Organization, Geneva, from 28 June to 2 July 1993. Dr K.W. Jager, of the IPCS, welcomed the participants on behalf of Dr M. Mercier, Director IPCS, and the three cooperating organizations (UNEP/ILO/WHO).

The Group reviewed and revised the draft criteria monograph and made an evaluation of the risks for human health and the environment from exposure to brominated diphenyl ethers.

The first draft of the monograph was prepared by Dr G .J. van Esch of the Netherlands, who also prepared the second draft, incorporating comments received following circulation of the first draft to the IPCS contact points for Environmental Health Criteria monographs.

Dr K.W. Jager of the IPCS Central Unit was responsible for the scientific content of the monograph, and Mrs M.O. Head of Oxford, England, for the editing.

The fact that industry made proprietary toxicological information available to the IPCS and the Task Group on the products under discussion is gratefully acknowledged. This allowed the Task Group to make its evaluation on a more complete data base.

The efforts of all who helped in the preparation and finalization of the document are gratefully acknowledged.

23

(26)

(27)

BROMINATED DIPHENYL ETHERS

GENERAL INTRODUCTION

(28)

(29)

1. GENERAL REMARKS

This Environmental Health Criteria monograph on brominated diphenyl ethers has been prepared as part of an overview on the impact of a number of flame retardants on human health and the environment. The group of polybrominated diphenyl ethers (PBDE) has been selected as a priority because of the recent interest in these substances. Only products based on penta-, octa-, and decabromodiphenyl ethers are of commercial interest.

The general chemical formula of brominated diphenyl ethers is:

6 0 ^6'

Polybrominated diphenyl ethers (PBDE) have a large number of congeners, depending on the number and position of the bromine atoms on the two phenyl rings. The total number of possible congeners is 209, and the numbers of isomers for mono-, di-, tri- up to decabromodiphenyl ethers are: 3, 12, 24, 42, 46, 42, 24, 12, 3, and I, respectively.

The commercial PBDE are produced hy the bromination of diphenyl oxide under certain conditions, which result in products containing mixtures of brominated diphenyl ethers (see the individual PBDE). The compositions of commercial DeBDE.

OBDE, and PeBDE are given in Table 1.

27

(30)

Table 1. Compos1t1on of commercial brominated diphenyl ethers Product

DeBDE OBDE PeBDE TeBDEb

PBDE⁸

7.6%

8Unknown structure.

TrBDE

0-1%

TeBDE PeBDE

24-38% 50-62%

41-41.7% 44.4-45%

bNo longer commercially produced. Analysis of one smgle sample.

Compos1t10n

HxBDE HpBDE

10-12% 43-44%

4-8%

6-7%

OBDE NBDE

0.3-3%

31-35% 9-11%

DeBDE 97-98%

0-1%

(31)

General introduction

No, or virtually no, data are available on dibromo-, tri- bromo-, hexabromo-, heptabromo-, and nonabromodiphenyl ether (DiBDE, TrBDE, HxBDE, HpBDE, and NBDE, respectively).

Flame retardants containing predominantly penta-, octa- and decabromodiphenyl ethers are commercially produced (with tetrabromodiphenyl ether as a major component of "pentabromodiphenyl ether", which is a mixture).

The commercial PBDE are rather stable compounds with boiling points ranging between 310 and 425

oc

and with low vapour pressures, e.g., 3.85 up to 13.3 Pa at 20-25

oc;

they are lipophilic substances. Their solubility in water is very poor, especially that of the higher brominated diphenyl ethers, and the n-octanol!water partition coefficients (log Pow) range between 4.28 and 9.9.

Polybrominated diphenyl ethers have not been reported to occur naturally in the environment, but other types of brominated diphenyl ethers have been found in marine organisms (Carte &

Faulkner, 1981; Faulkner, 1990).

The presence in the environment of some of the brominated diphenyl ethers has been documented, the highest concentration being 1 g/kg sediment in streams or ponds in the vicinity of a manufacturing facility.

Data on environmental fate, although limited to MBDE, DiBDE, and DeBDE, suggest that biodegradation is not an important degradation pathway for the PBDE, but that photodegradation may play a significant role.

Many reports have appeared in the literature describing the behaviour of brominated flame retardants under pyrolytic conditions. In general, these reports have indicated that maximum concentrations of PBDF and/or PBDD Wt""e observed at tempera- tures of 400-800

oc

and that the 2,3, 7 ,8-substituted compounds were seen only in very low concentrations.

Processing of the polymers under abusive or extreme conditions produced higher levels of PBDF, but the concentrations were significantly lower than the values previously reported from laboratory pyrolysis studies. 2,3, 7 ,8-Brominated isomers were only found at low levels in a sample abusively processed. The 2,3, 7 ,8-brominated isomers, which are of concern for toxicological 29

(32)

and regulatory reasons, were not detected under normal processing conditions. The results of the laboratory pyrolysis experiments with PBDE, showed that PBDF and/or PBDD were formed in various concentrations, depending on the type of PBDE, the polymer matrix, the specific processing conditions (temperature, presence of oxygen, etc.) and equipment used, and the presence of Sb₂0_{3 .} Behaviour of PBDE is strongly dependent upon the polymer matrix and upon the specific processing conditions mentioned above, thus laboratory pyrolysis experiments can hardly be used as reliable models to predict behaviour in commercial moulding operations.

(33)

2. GENERAL INFORMATION ON BROMINATED DIPHENYL ETHERS

2.1 Analytical methods

Several methods to determine residues of PBDE in various media (air, sewage sludge, sediment, human adipose tissue, marine organisms, fish, and feed) as well as in commercial products have been reported. For details, see Table 2.

In general, sample extraction and clean-up techniques for the analysis of PBDE residues in biological samples are similar to those developed for PBB (see EHC 152: Polybrominated biphenyls), though the chromatographic conditions have to be modified in view of the long retention times of the highly brominated PBDE. Temperature programming and the use of capillary columns have been found to be very useful for the separation of the different congeners of PBDE. Recovery for the different PBDE is generally higher than 80%. Most methods are based on extraction with organic solvents, such as hexane/

acetone, hexane/diphenyl ether, acetone, etc, purification of the extracts by gel permeation or adsorption chromatography, and determination mainly by gas chromatography, either with electron capture detection (ECD), or, coupled with mass spectrometry (MS). A multi-residue method has also been developed that includes a multi-step separation enabling the determination of several polychlorinated and polybrominated pollutants in biological samples (Jansson et al., 1991).

2.2 Production levels and processes

According to the information given by the European Brominated Flame Retardant Industry Panel (EBFRIP), eight manufacturers are currently producing polybrominated diphenyl ethers. They are: Dead Sea Bromines/Eurobrome (The Netherlands); Atochem (France); Ethyl Corporation (USA); Great Lakes Chemical Corporation (USA); Tosoh (Japan); Matsunaga (Japan); Nippo (Japan); Great Lakes Chemical Ltd (United Kingdom).

31

(34)

Table 2. Analytical methods for PBDE Sample

Sewage

Sed1ment

Fish

Animal tissues (Mult1-res1due method)

Rat liver

Extraction and clean-up

extract w1th chloroform; evaporate and dissolve residue in ethanol

extract with acetone; clean-up on Flons1l

extract w1th acetone-hexane + hexane-ethyl ether;

treatment With sulfunc ac1d or clean-up on alumina;

chromatography on s11ica gel

homogenize; extract With n-hexane-acetone;

treatment w1th sulfuric acid; gel permeation chromatography; chromatography or silica gel;

chromatography or activated charcoal extract with tetrahydrofuran

Separation and detection GC/MS

NAA;

GC/EC GC/EC;

GC/MS

GC/MS (NCI)

HPLC

Limit of Reference determination

0.06 mg/kg Kaart & Kokk (1987)

< 5 pg/kg Watanabe et el.

< 5 pg/kg (1987b)

lim1t of Andersson &

detection Blomkvist 0. 1 mg/kg fat (1981) 10 ng/kg Jansson et el.

(1991)

Rogers & Hill (1980)

(35)

w w

Table 2 (continued) F1sh

Cow's m1lk

Human m1lk

Human adipose tissue

Commercial PBDE

extract freeze-dned powdered sample w1th pet. ether;

gel permeation chromatography; clean-up on Flonsil;

elute With hexane

centrifuge; gel permeation chromatography; clean-up on Flons1l; elute with hexane

extract with potass1um oxalate/ethanol/d1ethyl ether/pentane; gel permeation chromatography; clean- up on Florisil; elute with hexane

extract with methylene chlonde; evaporate; clean-up on silica gel followed by clean-up on alumina and on a carbon/silica gel column

homogenize and d1ssolve in tetrachloromethane for HPLC and GC/MS or n-hexane for TLC/UV

8H1gh resolution gas chromatography/high resolution mass spectrometry.

GC/MS (NCI/SIM)

GC/MS (NCI/SIM) GC/MS (NCI/SIM)

HRGC/HRMS⁸

HPLC; GC/MS;

TLC/UV

< 5 pg/kg fat

< 2.5 pg/kg fat

< 0.6 !Jg/kg fat

lim1t of detection 0.73-120 ng!kg (different congeners)

Kruger ( 1988)

Kruger (1988)

Cramer et al.

(1990a,b)

deKok et al.

(1979)

(36)

The annual global consumption of PBDE is 40 000 tonnes (30 000 tonnes of DeBDE; 6000 tonnes OBDE and 4000 tonnes PeBDE) (Arias, 1992).

It has been reported that the use of brominated flame retardants in Japan increased from 2500 tonnes in 1975 to 22 100 tonnes in 1987 (Watanabe & Tatsukawa, 1990).

The production and import figures for the European Economic Community (EEC) are given in Table 3.

Table 3. Production and import quantities of PBDE 1n metric tonnes in the EEC ..

1986 1987 1988 1989

Production 4276 3624 4066 3843

Import 4310 3492 4955 7103

Total 8586 7116 9021 10 946

.. From: EBFRIP (19901.

Data on the usage of PBDE are available for some individual European countries. Germany uses 3000-5000 tonnes/year, Sweden 1400-2000 tonnes/year, and The Netherlands 3300-3700 tonnes/year (OECD, 1991; van Zorge, 1992), but Pijnenburg &

Everts (1991) and Pijnenburg et al. (1992) reported a level of 2500 tonnes PBDE for the last country. In the United Kingdom, up to 2000 tonnes per year are used (UK DOE, 1993).

Because of the significant reduction in the fire hazard for the public achieved by the use of PBDE in a wide range of applications, particularly in the furniture industry, and electrical/computer components and housing, the consumption of PBDE has significantly increased over the last years (EBFRIP, 1990).

2.3 Resins, polymers, and substrates in which PBDE are used

The major uses of the polybrominated diphenyl ethers in descending order of importance are: high-impact polystyrene,

(37)

wire and cable insulation, electrical/electronic connectors and other interior parts. These applications account for at least 80-90% of the consumption of brominated diphenyl ethers in the USA.

Brominated diphenyl ethers are used as additive flame retardants. Additive flame retardants are incorporated into the plastic matrix like other additives, such as plasticizers. The ideal additive is inexpensive, colourless, easily blended, compatible, heat and light stable, efficient, permanent, and has no deleterious effect on the properties of the base polymer. The most important limitations are incompatibilities that affect the physical properties of the polymers and the tendency for additives to be fugitive.

These additive flame retardants are much more prone to leaching or escape from the finished polymer product than the reactive flame retardants (Hutzinger et al., 1976; Hutzinger & Thoma, 1987; Larsen, 1980).

The uses of penta-, octa-, and decabromodiphenyl ethers in the different resins, polymers, and substrates are shown in Table 4. The principal applications of these PBDE-containing substances are shown in Table 5.

PBDE are used in the different resins, polymers, and substrates at levels ranging from 5 up to 30%. The quantities used for each application are not publicly available. In consumer products, resins containing PBDE are typically used in interior parts, minimizing the potential for exposure of the public. The incorporation of the PBDE into the polymer matrix further reduces the possibilities of exposure (EBFRIP, 1990).

35

(38)

Table 4. Use of penta- (PeBDE), octa- (OBOE), and decabromodiphenyl ethers (DeBOE) in resms, polymers, and substrates⁸

Resins/polymers/substrates DeBOE OBOE PeBDE

ABS X

Epoxy-resins X

Phenolic resins X X

PAN X

PA X X

PBT X X

PE/XPE X

PET X

pp _X

PS, HIPS X X

PVC X X

PUR X

UPE X X

Rubber X X

Paints/lacquers X X

Textoles X X

8From: EBFRIP (1990); UK Department of Envoronment (1 992).

(39)

Table 5. The vanous applications of resins in which PBDE are used are listed below⁸

Polymer ABS

EPOXY

PAINTS/

LACQUERS PHENOLICS

PAN

PA

PBT

PE/XPE

PET

Pnncipal applications Moulded parts

C1rcu1t boards, protective coatings Coatings

Printed circuit boards

Panels, electrical components

Electncal connectors, automatlve interior parts

Electrical connectors and components

Cross-linked w1re and cable, foam tubmg, weather protection and m01sture barriers

Electncal components

Examples of final products TV-sets/business machmes, computer housings, household appliances (hairdryer, curler).

automotive parts, electromcs, telecommunications Computers, sh1p Interiors, electronic parts

Marine and industry lacquers for protection of containers Paper laminates/glass prepregs for printed c1rcuit boards Lighting panels for elevators and rooms, housmg of electncal appliances

Computers, connectors, housing in electrical mdustry, board, electncal connectors, automotive industry, transportation

Switches, fuse, sw1tch box, computer housings, switch- board electncal connectors, stereos, business machines, military electromcs

Major application: power cable with cross-linked low density PE; also used for conduit for building With high dens1ty PE;

Fmal uses: portable apparatus bu1ldmg control, Instrument, shipboard, automotive, manne appliances, 1nsulat1on of heatmg tubes

Boxes, relays, coils, bobbms

37

(40)

Table 5 (contd) pp

PS, HIPS

PVC

PUR

RUBBER

TEXTILES

UPE

Conduits, electromc dev1ces

TV cabmets and back covers, electrical appliance housmgs

Cable sheets

Cush1omng materials, packaging, paddmg

Transportation

Coatmgs

C1rcu1t boards, coatmgs

8From: EBFRIP (1990).

TV and electromc dev1ces, such as yoke, housmgs, c1rcuit board hangers, condu1ts; Fmal uses:

electro-mechamcal parts TV, hot waste water p1pes, underground )Unction boxes TV back panels, computer covers and housmgs of electr~cal appliances, off1ce machmes, smoke detectors W1re and cables, floor mats, mdustr~al sheets

Furn1ture, sound msulat1on panels, wood 1mitat1ons, transportation

Conveyor belts, foamed p1pes for msulat1on

Back coatmgs, 1mpregnat1on:

carpets, automotive seatmg, furniture 1n homes and off1c1al buildmgs, aircraft, under- grounds, tents, tra1ns, anci military safety clothmg Electrical equ1pment, coatings for chemical processing plants mouldmgs, military and mar1ne applications: construction panels

(41)

3. FORMATION OF BROMINATED DIBENZOFURANS AND DIBENZODIOXINS FROM POLYBROMINATED

DIPHENYL ETHERS

3.1 General

Polybrominated dibenzofurans (PBDF) and polybrominated dibenzodioxins (PBDD) can be formed from polybrominated diphenyl ethers, polybrominated phenols, and polybrominated biphenyls under different conditions, including heating (combustion). Laboratory experiments have also demonstrated the formation of PBDF and PBDD during the pyrolysis of certain other brominated flame retardants (see the EHC on Brominated flame retardants, in preparation). As discussed in EHC 88:

Polychlorinated dibenzo-para-dioxins and dibenzofurans, there are hundreds of possible congeners of halogenated dibenzofurans and dibenzo-dioxins. However, only congeners with substituents in the 2,3, 7 ,8-positions are of toxicological significance. In many reports, only the total levels of PBDF and PBDD are given, without regard to substitution pattern; such totals are of limited value in the estimation of possible risk.

Hutzinger & co-workers investigated the pyrolysis of brominated flame retardants and flame retardant polymer systems and several publications have appeared. In general, the results reported showed that brominated dibenzofurans were observed at 700-800

oc

and that the 2,3, 7 .8-substituted compounds were seen in only low concentrations, if at all (Thoma et al., 1987a,b;

Thoma & Hutzinger. 1987; Dumler et al.. 1989).

Short! y after the initial reports of Buser and Hutzinger, BFRIP and German chemical companies (Bayer, BASF, and Hoechst) and American industries independently reported the results of combustion and pyrolysis experiments with flame retarded polymers (BFRIP. 1990).

Recent! y, brominated aromatic compounds have also attracted attention. since reports have appeared about emissions of PBDD and PBDF and other brominated and mixed halogenated aromatic compounds in accidental fires and from the combustion of waste (see section 4 of both DeBDE and OBDE).

39

(42)

For more information on these pyrolysis experiments, see the different sections relating to the individual brominated diphenyl ethers, e.g., PeBDE, OBDE, and DeBDE.

As an example, the formation of PBDF and PBDD from decabromodiphenyl ether is illustrated in Fig. 1.

- nBr•

~0~

Br,.

~r ¹ ~

0

+ ( 0 )

~

^Br,. ^Br,

+ ( H l

(c)("

0

"1'01 -

^HBr

f'?>i .. ~~""\ ^{" '}

''· ^,,, ^~

PBDF

+ ( H l o·H a;.:@ : ... ^: 'a·;··i-io

- 2 H8r •

Br,. : ... : Br

1 Br,.

PBDD

F1g. 1. Poss1ble mechan1sms for the format1on of PBDF and PBDD from decabromod1phenyl ether. From: B1enek et al. (1989).

Br,

(43)

3.2 Additional data on the pyrolysis of non-specified PBDE and/or polymers containing non-specified PBDE

The earliest published work on the pyrolysis of brominated flame retardants was that of Buser, whose first paper appeared in 1986 (Buser, 1986). Buser pyrolysed three technical PBDE mixtures with different degrees of bromination from commercial sources (pentabromo-, 71% bromine; octabromo-, 79% bromine (predominantly hexa- to nonabrominated PBDE) and decabromo-, 83% bromine, 97% DeBDE) at 510-630

oc

in small quartz vials.

The vials were placed in a heated oven for about one minute, and the contents analysed.

A range of PBDD and PBDF was found with a total yield of up to 10%. HRGG/MS analysis revealed the formation of reasonably simple mixtures of reaction products with often one or two main PBDF- and PBDD-isomers. Debromination reactions lead to lower brominated PBDF and PBDD congeners. In general, the higher brominated PBDE lead to higher brominated PBDF and PBDD. Most likely, the PBDF and PBDD are formed in intramolecular cyclization reactions involving the attack by oxygen on the diphenyl ether system (Fig. 1) (Buser, 1986; Bieniek et al.,

1989).

The next report to appear in the literature was also in 1986 from the laboratory of Hutzinger. Hutzinger's group pyrolysed penta- and decabromodiphenyl ethers at 700, 800, and 900

oc.

ⁱⁿ

a quartz tube oven, for about 10 min. They did not provide any isomer-specific results, but they reported the formation of PBDF and PBDD. Hutzinger continued to investigate the pyrolysis of brominated flame retardants and brominated flame retardant polymer systems, and several publications appeared (Thoma et al., 1987a,b; Thoma & Hutzinger, 1987; Dumler et al., 1989a). In general, the results reported in these publications were consistent with those of earlier work in that maximum concentrations of PBDF were observed at 700-800

oc

and 2,3, 7 ,8-substituted compounds were seen only in very low concentrations, if at all.

Shortly after the initial reports of Buser and Hutzinger, BFRIP and German chemical companies (Bayer, BASF and Hoechst) independently reported the results of combustion and pyrolysis experiments with flame retarded polymers.

41

THE ENVIRONMENTAL

Environmental Health Criteria 162

BROMINATED DIPHENYL ETHERS

* * *

* * *

BROMINATED DIPHENYL ETHERS

GENERAL INTRODUCTION

6 0 6'

oc

oc;

oc

oc

~0~

~r 1 ~

~

~

(c)("

"1'01 -

f'?>i .. ~~""\ " '

''· ,,, ~

oc

oc.

oc

6 0 ^6'

~r ¹ ~

f'?>i .. ~~""\ ^{" '}

''· ^,,, ^~