IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
Health and Safety Guide No. 8
EPICHLOROHYDRIN
HEALTH AND SAFETY GUIDE
UNITED NATIONS ENVIRONMENT PROGRAMME
INTERNATIONAL LABOUR ORGANISATION
WORLD HEALTH ORGANIZATION
WORLD HEALTH ORGANIZATION, GENEVA 1987
This is a companion volume to Environmental Health Criteria
33: Epichlorohydrin
Published by the World Health Organization for the International
Programme on Chemical Safety (a collaborative programme of the United
Nations Environment Programme, the International Labour Organisation,
and the World Health Organization)
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
ISBN 92 4 154333 7
ISSN 0259-7268
The World Health Organization welcomes requests for permission to
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Applications and enquiries should be addressed to the Office of
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will be glad to provide the latest information on any changes made to
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(c) World Health Organization 1987
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CONTENTS
IPCS
HEALTH AND SAFETY GUIDE FOR EPICHLOROHYDRIN
INTRODUCTION
HOW TO USE THE GUIDE
1. PRODUCT IDENTITY AND USES
1.1. Identity
1.2. Physical and chemical properties
1.3. Composition
1.4. Uses
2. SUMMARY AND EVALUATION
2.1. Exposure to epichlorohydrin
2.2. Uptake, metabolism, and excretion
2.3. Effects on animals
2.4. Effects on human beings
3. CONCLUSIONS
4. HEALTH HAZARDS FOR MAN, PREVENTION AND PROTECTION, EMERGENCY
ACTION
4.1. Main hazards for man, prevention and protection,
first aid
4.2. Advice to physicians
4.3. Health surveillance advice
4.4. Explosion and fire hazards, prevention
4.4.1. Explosion hazards
4.4.2. Fire hazards
4.4.3. Prevention
4.4.4. Fire-extinguishing agents
4.5. Storage
4.6. Transport
4.7. Spillage and disposal
4.7.1. Spillage
4.7.2. Disposal (based on IRPTC waste disposal file)
5. INTERNATIONAL CHEMICAL SAFETY CARD
6. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION
7. CURRENT REGULATIONS, GUIDELINES, AND STANDARDS
7.1. Exposure limit values
7.2. Specific restrictions
7.3. Labelling, packaging, and transport
7.4. Waste disposal
7.5. Other measures
INTRODUCTION
The International Programme on Chemical Safety is responsible for the
publication of a series of Environmental Health Criteria documents,
each of which assesses the existing information on the relationship
between exposure to a specific chemical, mixture of chemicals, or
combination of chemicals and physical and biological agents, and man's
health and the integrity of the environment. The documents provide
guidelines for setting exposure limits consistent with the protection
of human health and the environment.
To facilitate the application of these guidelines in national chemical
safety programmes, "Health and Safety Guides" are being prepared,
highlighting the information contained in the documents for those who
need to know the health and environmental issues involved, but not the
scientific details. The Guides include advice on preventive and
protective measures and emergency action.
Review and revision of the information in this Health and Safety Guide
will take place in due course, and the eventual aim is to use
standardized terminology. We should be grateful if you would help by
telling us of any difficulties encountered in using the information in
this guide.
Comments please, addressed to:
The Manager
International Programme on Chemical Safety
Division of Environmental Health
World Health Organization
1211 Geneva 27
Switzerland
HOW TO USE THE GUIDE
All people in the work-place environment should be given the relevant
written information in this book, supplemented by a clear, personal
explanation to ensure that they are fully aware of the dangers and the
current courses of protective and emergency action.
The International Chemical Safety Card should be displayed as directed
and its contents clearly explained to all working personnel. Medical
staff should be fully conversant with the medical information to
ensure they can act rapidly and efficiently in an emergency. Posters
should be used to give impact to basic safety measures.
Further copies of the Health and Safety Guide and, for those requiring
more detailed scientific information, the relevant Environmental
Health Criteria publication, are available to order.
THE INFORMATION IN THIS GUIDE SHOULD BE CONSIDERED AS A STARTING POINT
TO A COMPREHENSIVE HEALTH AND SAFETY PROGRAMME
1. PRODUCT IDENTITY AND USES
1.1 Identity
Chemical formula: C3H5ClO
Chemical structure: O
/ \
/ \
CH2 - CH - CH2Cl
Common synonyms: alpha-epichlorohydrin; CEP;
1-chloro-2,3-epoxypropane;
3-chloro-1,2-epoxypropane;
(chloromethyl)-ethylene oxide;
chlormethyloxirane; 2-(chloromethyl)
oxirane; 1-chloropropene oxide;
3-chloropropene oxide;
3-chloro-1,2-propylene oxide;
(DL)-alpha-epichlorohydrin; ECH; ECHH;
EPI; 1-epichlorohydrin;
1,2-epoxy-3-chloropropane; 2,3-epoxypropyl
chloride; gamma-chloropropylene oxide;
glycerol epichlorohydrin; glycidyl chloride
CAS registry number: 106-89-8
Conversion factors
1 ppm epichlorohydrin = 3.78 mg/m3 at
25°C and 101.3 kPa (760 mm Hg);
1 mg/m3 - 0.265 ppm
1.2 Physical and Chemical Properties
Some physical and chemical properties of epichlorohydrin are given in
the Sample International Chemical Safety Card.
1.3 Composition
The technical product is more than 98% pure.
Depending on its source, epichlorohydrin contains different
impurities, among which may be chlorinated ethers, 1,4-dichlorohexane,
and several chlorinated propenes.
1.4 Uses
Epichlorohydrin is usually prepared from propene and is mainly used in
the manufacture of glycerol and epoxy resins. It is also used: in the
manufacture of elastomers, glycidyl ethers, cross-linked food starch,
surfactants, plasticizers, dyestuffs, pharmaceutical products, oil
emulsifiers, lubricants, and adhesives; as a solvent for resins, gums,
cellulose, esters, paints, and lacquers; and as a stabilizer in
chlorine-containing substances such as rubber, pesticide formulations,
and solvents.
2. SUMMARY AND EVALUATION
2.1 Exposure to epichlorohydrin
Epichlorohydrin is released into the environment as a result of its
manufacture, use, and disposal.
Human exposure to epichlorohydrin mainly occurs at the work-place
through inhalation and skin contact.
Some epichlorohydrin may occur in food and drinking-water as a result
of migration from packaging and tubing materials.
In the atmosphere, epichlorohydrin is probably degraded under the
influence of sunlight.
The compound is expected to disappear rapidly from water via chemical
degradation and evaporation; it is biodegradable.
2.2 Uptake, Metabolism, and Excretion
Epichlorohydrin is absorbed rapidly into the body through the skin,
and after ingestion or inhalation. It is distributed widely throughout
the body.
The highest tissue concentrations in rodents were found in the nose
after inhalation, and in the stomach after ingestion. In rats,
regardless of the route of exposure, most absorbed epichlorohydrin is
metabolized rapidly, part being excreted as carbon dioxide via the
lungs and part as water-soluble compounds via the urine.
2.3 Effects on Animals
For single exposures, epichlorohydrin is moderately toxic after oral
exposure and slightly toxic after inhalation exposure.
Oral doses of 260 mg/kg body weight (LD50) and inhalation exposure
to vapour concentrations of 2400 mg/m3 for 4 h or 1360 mg/m3 for 6 h
(LC50) have been shown to be lethal for half the number of exposed
rats. Concentrations of epichlorohydrin of between 18 and 36 mg/litre
water have been shown to be lethal for half the number of fish
(LC50) exposed for 2-4 days.
Exposure to epichlorohydrin induced sterility in male rodents.
No evidence has been obtained of any embryotoxic, fetotoxic, or
teratogenic effects in animals.
Epichlorohydrin is an alkylating agent, but the extent of its reaction
with nucleic acid and proteins is unknown.
The compound is mutagenic in a variety of tests.
In animals, epichlorohydrin is carcinogenic when administered by
inhalation, orally, or by subcutaneous injection. Tumours are induced
at the site of administration, i.e., the nasal epithelium after
inhalation, forestomach epithelium after garage and drinking-water
administration, and the site of injection after injection.
In one study, the compound initiated skin neoplasms in mice.
2.4 Effects on Human Beings
Epichlorohydrin vapour is strongly irritating to the human eye and
respiratory tract, and local contact will result in protracted skin
burns and blisters, though the effects may not appear until some time
after exposure. Epichlorohydrin can sensitize the skin of human
beings.
On the basis of observations following short-term inhalation exposures
to epichlorohydrin, human beings are likely to begin to experience eye
and upper respiratory tract irritation at concentrations of
approximately 76 mg/m3.
Studies on human beings and animals show adverse effects on the
central nervous system, nose, throat, lungs, liver, blood, eyes, and
skin. Degenerative effects on the kidneys, which have been clearly
demonstrated in rodents, have not been found in human beings, so far.
Limited epidemiological studies have not revealed any effects on the
fertility status of male workers exposed to epichlorohydrin.
Conflicting results were obtained when the lymphocytes of workers,
occupationally exposed to concentrations below 19 mg/m3, were
examined for chromosomal aberrations.
Up to the present, epidemiological studies have not provided evidence
of carcinogenicity in human beings due to exposure to epichlorohydrin.
However, the studies have all been limited by small numbers, short
duration of follow-up, and the fact that confounding factors were not
sufficiently considered. Thus, no definite conclusions can be drawn
from them.
3. CONCLUSIONS
On the basis of the above data, it can be concluded that
epichlorohydrin is mutagenic and carcinogenic for experimental
animals, causes sterility in male rodents, and could be carcinogenic
for human beings.
From: Environmental Health Criteria 33: Epichlorohydrin
4. HEALTH HAZARDS FOR MAN, PREVENTION AND PROTECTION, EMERGENCY
ACTION
4.1 Main Hazards for Man, Prevention and Protection, First Aid
Epichlorohydrin vapour irritates the skin, eyes, nose, throat, and
lungs, and may cause excessive accumulation of fluid in the lungs
(oedema). The liquid is severely irritating to the skin and eyes after
local contact, and to the mouth, throat, and stomach, after ingestion.
Epichlorohydrin can sensitize the skin. The compound affects the
central nervous system and liver, and is a suspected carcinogen.
Human health hazards associated with certain types of exposure to
epichlorohydrin together with preventive and protective measures and
first aid recommendations are listed in the following table.
GOLDEN RULES
1. Do not smoke, drink, or eat in the work-place.
2. In case of overexposure, the victim should leave, or be removed
from, the contaminated area to fresh air as rapidly as possible.
3. Remove contaminated clothing and shoes and wash with plenty of
water and soap.
4. Flush affected eye(s) with water for at least 15 minutes.
4.2 Advice to Physicians
No specific antidote is known. Treat symptomatically. Oxygen may be
required. Treat blisters on skin as for a thermal burn. Pay attention
to occurrence of pulmonary oedema (complete bed rest!).
Check liver function.
4.3 Health Surveillance Advice
Human beings likely to be exposed to epichlorohydrin should undergo
medical examination, once a year, with emphasis on skin and eye
disorders and liver function.
ROUTE HEALTH HAZARDS PREVENTION AND PROTECTION FIRST AID
SINGLE EXPOSURE
SKIN Severe irritation by both liquid Avoid exposure, wear Remove contaminated clothing
and vapour; skin burns on direct impervious clothing, gloves, and shoes; wash skin with
contact (may be delayed); sensitization and face shield (made of plenty of water; seek medical
may occur polyethylene, polypropylene, attention
or poly(vinyl)chloride; unsuitable
materials are neoprene, rubber,
or leather); provide emergency
showers
EYES Severe irritation by both liquid Avoid exposure; wear safety Flush with plenty of water
and vapour; corrosive goggles and face shield; for at least 15 minutes; seek
provide eyewash medical attention immediately
INHALATION Irritation of nose, throat, and lungs; Avoid exposure; apply Remove victims to fresh air and
lung oedema; effects on the central ventilation, local exhaust, keep quiet in half upright
nervous system such as difficult or breathing protection by a position; if breathing has
breathing (respiratory depression); suitable respirator stopped, apply artificial
headache; nausea and vomiting; respiration; seek medical
effects on liver attention immediately
INGESTION Irritation and corrosion of mouth, Do not eat, drink or smoke Rinse mouth; give milk with
throat, and stomach; death by when handling epichlorohydrin water to drink, and induce
respiratory failure vomiting in conscious patients;
transport to hospital immediately
ROUTE HEALTH HAZARDS PREVENTION AND PROTECTION FIRST AID
REPEATED EXPOSURE
SKIN Sensitization
INHALATION Inflammation of nose, throat, Avoid exposure; apply
and lungs; liver damage ventilation or local exhaust
GENERAL Potential carcinogen
4.4 Explosion and Fire Hazards, Prevention
4.4.1 Explosion hazards
Epichlorohydrin-air mixtures containing 3.8-21% epichlorohydrin by
volume are explosive above 34°C and can be ignited by hot surfaces,
sparks, and open flames. The vapour is heavier than air and may travel
along the ground and be ignited at a distance. Contact with strong
acids and bases, zinc, aluminium, metal chlorides, alcohol-containing
materials, isopropylamine, trichloroethylene, and oxidizing agents may
cause fire and explosions.
4.4.2 Fire hazards
Epichlorohydrin is a flammable liquid. The compound decomposes in
contact with open flames and glowing surfaces with the formation of
harmful gases such as hydrogen chloride, which forms mists of
hydrochloric acid with moisture, phosgene, and carbon monoxide. In a
fire, the compound may polymerize and burst its container.
4.4.3 Prevention
Do not use epichlorohydrin in the vicinity of a fire, a hot surface,
or during welding. Do not smoke. In case of fire, shut off
epichlorohydrin sources; containers of epichlorohydrin should be
removed or cooled by spraying with water. Fire-fighters should wear
proper respiratory protective devices and protective clothing.
4.4.4 Fire-extinguishing agents
Powder, alcohol-resistant foam, water sprays, halons, and carbon
dioxide.
4.5 Storage
Epichlorohydrin should be stored in tightly closed, labelled
containers in fire-proof, cool, dry rooms. Apply ventilation across
the floor. Epichlorohydrin attacks steel in the presence of moisture.
The compound should be stored away from strong acids and bases, zinc,
aluminium, metal chlorides, alcohol-containing material,
isopropylamine, trichloroethylene, and oxidizing agents.
4.6 Transport
In case of accident during transport, stop the engine, extinguish
naked lights, and do not smoke. Keep bystanders away from the danger
spot, and mark the roads. Keep upwind. In case of spillage, use the
methods advised in section 4.7.
4.7 Spillage and Disposal
4.7.1 Spillage
Evacuate the area. Remove all ignition sources and collect leaking
liquid in sealable containers. Absorb spilled liquid in sand, paper
towels, or another inert absorbent, and remove to a safe place. Do not
allow epichlorohydrin to enter a confined space such as a sewer,
because of the possibility of an explosion. Ensure personal protection
by the use of self-contained breathing apparatus and protective
clothing (see following table).
4.7.2 Disposal (based on the IRPTC waste disposal file)
Epichlorohydrin wastes should be disposed of by incineration,
preferably after mixing with another combustible fuel. Assure complete
combustion to prevent formation of phosgene. An acid scrubber is
necessary to remove halo acids produced. Aqueous, epichlorohydrin-
containing wastes can be saponified by caustic solutions, and the
resulting glycerol can be biodegraded in sewage-treatment plants.
5. INTERNATIONAL CHEMICAL SAFETY CARD
This card should be easily available to all health workers concerned
with, and users of epichlorohydrin. It should be displayed at, or
near, entrances to areas where there is potential exposure to
epichlorohydrin, and on processing equipment and containers. The card
should be translated into the appropriate language(s).
All persons potentially exposed to the chemical should also have the
instructions on the chemical safety card clearly explained.
SAMPLE INTERNATIONAL CHEMICAL SAFETY CARD
EPICHLOROHYDRIN
(1-chloro-2,3-epoxypropane, chlormethyloxirane, ECH)
(OCH2CHCH2Cl)
PHYSICAL PROPERTIES OTHER CHARACTERISTICS
Relative molecular mass 92.53 Colourless liquid with a chloroform-like odour;
Appearance colourless liquid the compound decomposes in contact with open
Odour chloroform-like flames and glowing surfaces with formation of
Odour perception threshold 38-95 mg/m3 harmful gases; contact with strong acids and bases,
Melting point -57°C zinc, aluminium, metal chlorides, alcohol-containing
Boiling point 115°C materials, isopropylamine, trichloroethylene, and
Solubility in water (20°C) 66 g/litre oxidizing agents may cause fire and explosions; the
Density (20°C) 1.18 g/ml compound is heavier than air and may travel along the
Relative vapour density 3.21 ground and be ignited at a distance
Vapour pressure (20°C) 1.7 kPa (12.5 mmHg)
Flash point (open cup) 34°C
Flammable (explosive) limits 3.8 - 21%
Octanol/water partition coefficient 0.30
HAZARDS/SYMPTOMS PREVENTION AND PROTECTION FIRST AID
SKIN: Irritation; redness; pain; Avoid exposure, wear impervious Remove contaminated clothing and shoes immediately;
burns; blisters; sensitization clothes, gloves, face shield wash skin immediately with plenty of water
EYES: Irritation; redness, corrosion, pain Avoid exposure, wear safety Flush eyes immediately with plenty of water for at
goggles or face shield least 15 minutes; seek medical attention
SAMPLE INTERNATIONAL CHEMICAL SAFETY CARD (cont'd).
HAZARDS/SYMPTOMS PREVENTION AND PROTECTION FIRST AID
INHALATION: Irritation of nose, throat, Avoid exposure, use ventilation, Fresh air, rest; if breathing has stopped, apply
lungs; lung oedema; effects on nervous local exhaust or breathing artificial respiration; in serious cases, seek medical
system with breathing difficulties protection attention immediately
INGESTION: Irritation and corrosion of Do not eat, drink, or smoke Rinse mouth, give water to drink, induce vomiting
mouth, throat, stomach when handling the compound in conscious patients
GENERAL: Epichlorohydrin is a potential
carcinogen
SPILLAGE STORAGE FIRE AND EXPLOSION
Evacuate the area; remove ignition sources; Store in tightly closed, labelled Compound is flammable above 34°C; explosive
collect leaking liquid in sealable container in fire-proof, cool, vapour/air mixtures may be formed; no open flames;
containers; absorb spilled liquid in dry rooms away from incompatible no sparks; no smoking; above 34°C, closed system,
sand, paper towels, or other inert materials; ventilation across ventilation; fire extinguishing agents: powder, foam,
absorbent and remove to safe place; ensure the floor water spray, halons, carbon dioxide; in case of fire,
personal protection by using a remove containers or keep cool with water spray
self-contained breathing apparatus and
protective clothing
SAMPLE INTERNATIONAL CHEMICAL SAFETY CARD (cont'd).
WASTE DISPOSAL
Waste should be incinerated, preferably National Occupational UN: 2023
after mixing with a combustible fuel; Exposure Limit:
assure complete combustion and apply
acid scrubbing National Poison Control Centre:
NOTE: Do not use the compound in the vicinity of a fire, a hot surface, or during welding. Do not smoke. It is a strong sensitizer;
avoid skin contact and high vapour levels.
6. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION
Epichlorohydrin is moderately toxic for aquatic organisms.
Avoid contamination of soil, water, and the atmosphere by proper
methods of storage, transport, handling, and waste disposal. In case
of spillage, use the method advised in section 4.7.
Exhaust ventilation systems discharging to outside air must conform
with air pollution regulations.
7. CURRENT REGULATIONS, GUIDELINES, AND STANDARDS
The information given in this paragraph has been extracted from the
International Register of Potentially Toxic Chemicals (IRPTC) legal
file.
The reader should be aware that regulatory decisions about chemicals
taken in a certain country can only be fully understood in the
framework of the legislation of that country. A full reference to the
original national document from which the information was extracted
can be obtained from the IRPTC.a
When no effective date appears in the IRPTC legal file, the year of
the reference from which the data are taken is shown, indicated by
(r).
7.1 Exposure Limit Values
See the following table.
7.2 Specific Restrictions
In the USA, the substance is restricted for use as an ingredient of
pesticides to some specified purposes (1981 (r)). When used as a
starch modifier, it may not exceed certain limits (1981 (r)).
7.3 Labelling, Packaging, and Transport
The European Community legislation requires labelling as dangerous
substance using the symbol:
a International Register of Potentially Toxic Chemicals, Palais des
Nations, 1211 Geneva 10, Switzerland (Telephone No. 988400-985850).
The label must read: may cause cancer; flammable, keep container in
well-ventilated place; also toxic by inhalation, in contact with skin
and if swallowed -- causes burns and may cause sensitization by skin
contact -- avoid exposure, obtain special instructions before use; if
unwell, seek medical advice (and show label where possible).
The United Nations Committee of Experts on the Transport of Dangerous
Goods classifies epichlorohydrin as a toxic substance (Class 6.1) with
medium danger for packing purposes (Packing Group II). Packing methods
and a label are recommended (1982 (r)). The label is:
The International Maritime Organization also classifies
epichlorohydrin as a toxic substance and recommends packing, stowage,
and labelling methods for maritime transport (1977 (r)). The label is:
7.4 Waste Disposal
In the USA, any solid waste (except domestic) containing
epichlorohydrin must be listed as hazardous waste (subject to
handling, transport, treatment, storage, and disposal regulation and
permit and notification requirements), unless it is found that the
waste cannot pose a threat to human health or the environment
(effective date: 1980).
Permits are required for the discharge of epichlorohydrin from any
point source into USA waters (1981 (r)). Epichlorohydrin, and
solutions and mixtures containing the substance, are designated as
hazardous substances for the purpose of discharge (including spilling,
leaking, etc.) under the water pollution control act (1981 (r)).
7.5 Other Measures
The European Community legislation on the discharge of dangerous
substances into the aquatic environment prohibits the discharge of
epichlorohydrin into groundwater. For other waters, it requires that
national authorities give specific discharge authorizations with
discharge conditions (total quantity and concentration).
EXPOSURE LIMIT VALUES
Medium Specification Country/ Exposure limit descriptiona Value Effective
organization date
AIR Occupational Australia Threshold limit value (TLV) 1983 (r)
-- Time-weighted average (TWA) 20 mg/m3b
Belgium Threshold limit value (TLV) 19 mg/m3b
Czechoslovakia Maximum allowable concentration (MAC) 1985
-- Time-weighted average (TWA) 1 mg/m3
-- Ceiling value 2 mg/m3
Finland Maximum permissible concentration (MPC) 1982 (r)
-- Time-weighted average (TWA) 19 mg/m3b
German Maximum allowable concentration (MAC) 1983 (r)
Democratic -- Time-weighted average (TWA) 5 mg/m3b
Republic -- Short-term exposure limit (STEL) 10 mg/m3b
Germany, Federal Maximum work-site concentration (MAK) -b 1985 (r)
Republic of -- Carcinogen no MAK value
established
Germany, Federal Technical reference concentration (TRK) 1985 (r)
Republic of -- One-year time-weighted average = year 12 mg/m3
Hungary Maximum allowable concentration (MAC) 1978 (r)
-- Time-weighted average (TWA) 1 mg/m3
-- Short-term exposure limit (STEL) 2 mg/m3
EXPOSURE LIMIT VALUES (cont'd).
Medium Specification Country/ Exposure limit descriptiona Value Effective
organization date
Netherlands Maximum limit 1985 (r)
-- Time-weighted average (TWA) 4 mg/m3b
-- Short-term exposure limit (STEL) 20 mg/m3
(maximum 15 minutes each 2-h period)
Poland Maximum permissible concentration (MPC) 1982 (r)
-- Ceiling value 1 mg/m3
Romania Maximum permissible concentration (MPC) 1975 (r)
-- Time-weighted average (TWA) 5 mg/m3b
-- Ceiling value 10 mg/m3
AIR Occupational Sweden Hygienic limit value (HLV) 1985
-- One-day time-weighted average 1.9 mg/m3b
-- Short-term exposure limit (STEL) 4 mg/m3
(15-minute time-weighted average)
-- Carcinogen
Switzerland Maximum work-site concentration (MAK) 1984 (r)
-- Time-weighted average (TWA) 8 mg/m3 h
-- Carcinogen
United Kingdom Recommended limit 1985 (r)
-- 8-h time-weighted average 8 mg/m3b
-- Short-term exposure limit (STEL) 20 mg/m 3
(10-minute time-weighted average)
USA (ACGIH)c Threshold limit value (TLV) 1982 (r)
-- Time-weighted average (TWA) 10 mg/m3b
USA (ACGIH)c -- Short-term exposure limit (STEL) 20 mg/m3
EXPOSURE LIMIT VALUES (cont'd).
Medium Specification Country/ Exposure limit descriptiona Value Effective
organization date
USA (OSHA) Permissible exposure limit (PEL) 1981 (r)
-- Time-weighted average (IWA) 19 mg/m3b
USSR Maximum allowable concentration (MAC) 1977
-- Ceiling value for vapour 10 mg/m3
Yugoslavia Maximum allowable concentration (MAC) 1971 (r)
-- Time-weighted average (TWA) 18 mg/m3b
AIR Ambient USSR Maximum allowable concentration (MAC) 1984 (r)
-- Average per day 0.2 mg/m3
-- One time per day 0.2 mg/m3
WATER Surface USSR Maximum allowable concentration (MAC) 0.01 mg/litre 1983 (r)
a TWA = time-weighted average over one working day (usually 8 h).
b Skin absorption.
c Value recommended by the American Conference of Government Industrial Hygienists.