IPCS INTERNATIONAL PROGRAMME ON CHEMICAL SAFETY
Health and Safety Guide No. 10
TETRACHLOROETHYLENE
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
31: Tetrachloroethylene
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 154331 0
ISSN 0259-7268
The World Health Organization welcomes requests for permission to
reproduce or translate its publications, in part or in full.
Applications and enquiries should be addressed to the Office of
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(c) World Health Organization 1987
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CONTENTS
IPCS
HEALTH AND SAFETY GUIDE FOR TETRACHLOROETHYLENE
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 tetrachloroethylene
2.2. Fate of tetrachloroethylene
2.3. Uptake, metabolism, and excretion
2.4. Effects on animals
2.5. 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
4.4.1. Explosion hazards
4.4.2. Fire hazards
4.4.3. Prevention
4.5. Storage
4.6. Transport
4.7. Spillage and disposal
4.7.1. Spillage
4.7.2. Disposal (based on the 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
Molecular formula: C2Cl4
Chemical structure: Cl Cl
\ /
\ /
C = C
/ \
/ \
Cl Cl
Common trade names: Ankilostin; Antisal 1; Antisol 1;
Blancosolv No. 2; Dee Solve; Didakene;
Dowper; Ent 1860; Fedal Un; Mid Solv;
NeMa; Per; Perawin; Perc; Perchlot;
Perclene; Per-Ex; Perk; Perklone;
Perm-a-kleen; Persec; Phillsolv; Tetlen;
Tetracap; Tetraguer; Tetraleno; Tetralex;
Tetravec; Tetropil; Wacker-Per
Common synonyms: carbon dichloride; ethylene tetrachloride;
perchoroethylene; tetrachloroethene;
1,1,2,2-tetrachloroethylene
CAS registry number: 127-18-4
Conversion factors
1 mg/m3 = 0.147 ppm
1 ppm tetrachloroethylene = 6.78 mg/m3 at
25°C and 101.3 kPa (760 mm Hg).
1.2 Physical and Chemical Properties
Some physical and chemical properties of tetrachloroethylene are given
in the Sample International Chemical Safety Card.
1.3 Composition
Technical tetrachloroethylene contains stabilizers, the type and
concentration of which vary with grade and supplier.
1.4 Uses
Tetrachloroethylene is mainly used as a solvent in dry cleaning and
metal cleaning. It is also used for processing and finishing in the
textile industry, as an extraction solvent, veterinary anthelmintic,
heat-exchange fluid, grain fumigant, and in the manufacture of
fluorocarbons.
2. SUMMARY AND EVALUATION
2.1 Exposure to Tetrachloroethylene
Tetrachloroethylene is not known to occur naturally. Man-made
tetrachloroethylene can occur in air over rural and urban sites, in
sea-, surface-, ground-, and drinking-water, and in various
foodstuffs. The highest levels of tetrachloroethylene in air are found
in factories and dry-cleaning establishments.
Human exposure is mainly to the vapour of tetrachloroethylene, and
workers in dry-cleaning shops and factories are exposed to high
concentrations. People living near these establishments may also be
exposed to higher concentrations than the rest of the community. The
general population is exposed to low levels of tetrachloroethylene in
the ambient air, food, and drinking-water.
2.2 Fate of Tetrachloroethylene
Most tetrachloroethylene is released into the ambient air where it is
degraded by sunlight to form products such as hydrogen chloride,
trichloroacetic acid, and carbon dioxide. Tetrachloroethylene rapidly
evaporates from surface water, and little degradation takes place in
water. The compound is persistent in groundwater, which is reason for
concern considering the increasing incidence of contamination of
groundwater through industrial spillage and waste dumps.
2.3 Uptake, Metabolism, and Excretion
Tetrachloroethylene is absorbed via the skin, on direct contact, and
via the lungs, after inhalation. The amount of the chemical in the
body increases with increasing exposure level and with an increase in
physical exercise during exposure. It accumulates to a limited extent
in the fatty tissues of man and of animals, both of which are able to
metabolize it, principally to trichloroacetic acid, and sometimes also
to trichloroethanol. In all species, metabolic capacity is limited.
However, the extent of metabolism differs in different species.
In man, most tetrachloroethylene is excreted unchanged via the lungs.
Removal of tetrachloroethylene from blood and excretion in the breath
are slow, the amount increasing with increasing exposure level. The
concentrations of the compound in blood and breath can be used for
estimating exposure levels in man.
2.4 Effects on Animals
Oral doses of 13 000 mg/kg body weight and vapour concentrations of
27 800 mg/m3 for 6 h have been shown to be lethal for half of the
number of exposed rats in a population (LD50, LC50, respectively).
Tetrachloroethylene has been shown to be moderately toxic for aquatic
organisms, concentrations of between 3.5 and 21 mg/litre water being
lethal for half the number of organisms exposed for 2-4 days.
Results of studies on animals indicate that inhalation exposure to
tetrachloroethylene concentrations of approximately 1300 mg/m3 or
more appear to be associated with definable liver injury. However, the
level at which similar effects in the liver might occur in human
beings is not clear.
Embryotoxicity was observed in the progeny of experimental animals
exposed by inhalation, during gestation, to tetrachloroethylene
concentrations exceeding 2000 mg/m3. It is possible that similar
effects might occur in human beings exposed to such high
concentrations.
The available evidence is insufficient to regard tetrachloroethylene
as a mutagenic compound.
2.5 Effects on Human Beings
On the basis of results of repeated short-term, human, inhalation
exposure studies, it is considered that no acute effects will occur at
tetrachloroethylene concentrations of approximately 140 mg/m3 or
less.
The results of single or short-term human exposure to
tetrachloroethylene indicate that human beings are likely to begin to
experience eye irritation at air concentrations of approximately
500 mg/m3, and depression of the central nervous system and nose and
throat irritation at approximately 700 mg/m3. Such effects are
reversible on cessation of exposure, but increase in severity with
both increasing concentration and duration of exposure.
Because the excretion rate is relatively slow, levels of
tetrachloroethylene in the liver, kidneys, and fat following a large
dose are likely to remain high for several days after exposure.
Direct skin exposure may result in irritation of the skin. The
available data suggest that a no-observed-adverse-effect level will be
between 140 and 500 mg/m3.
Observations after repeated exposure to tetrachloroethylene, over
months or years, indicate that human beings inhaling
tetrachloroethylene are likely to begin to exhibit depression of the
central nervous system at concentrations exceeding approximately
700 mg/m3.
Workers in dry-cleaning plants, occupationally exposed to
concentrations of up to 2 700 mg/m3, did not show alterations in
liver enzyme activity.
3. CONCLUSIONS
Tetrachloroethylene was found to be carcinogenic for mice but not for
rats. Evidence from epidemiological studies among dry-cleaning and
laundry workers is insufficient to conclude that exposure to
tetrachloroethylene can cause cancer in human beings.
From: Environmental Health Criteria 31: Tetrachloroethylene
4. HEALTH HAZARDS FOR MAN, PREVENTION AND PROTECTION, EMERGENCY
ACTION
4.1 Main Hazards for Man, Prevention and Protection, First Aid
Tetrachloroethylene vapour irritates the skin, eyes, and respiratory
tract and affects the central nervous system. The liquid also
irritates the skin and eyes. The compound may be toxic for the human
embryo at high concentrations.
The human health hazards associated with certain types of exposure to
tetrachloroethylene 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. Avoid
vasopressor drugs, e.g. adrenaline.
4.3 Health Surveillance Advice
Human beings handling tetrachloroethylene should undergo medical
examination, once a year, with emphasis on the functioning of the
central nervous system and the liver, and on disorders of the skin and
eyes.
4.4 Explosion and Fire Hazards
4.4.1 Explosion hazards
Tetrachloroethylene is nonflammable, nonexplosive, and noncombustible.
Commercial grades are stabilized up to 140°C and, in the absence of
catalysts, light, and oxygen, up to 500°C.
Explosive mixtures are formed with zinc, light metals, such as
barium, beryllium, and lithium, and dinitrogen tetroxide (N2O4).
ROUTE HEALTH HAZARDS PREVENTION AND PROTECTION FIRST AID
SINGLE EXPOSURE
SKIN Irritation by both liquid and vapour Minimize exposure; wear Remove contaminated clothing
protective clothing and gloves and shoes; wash with plenty of
water and soap
EYES Irritation by both liquid and vapour Wear safety goggles Flush with plenty of water for
at least 15 minutes
INHALATION Irritation of nose and respiratory tract; Minimize exposure; apply local Remove victims to fresh air and
effects on the central nervous system, exhaust ventilation or breathing keep them quiet; if breathing
such as light-headedness, dizziness, protection by means of a suitable has stopped, apply artificial
drowsiness, headache, nausea, fatigue; respirator; because of the respiration
in severe overexposure, impaired possibility of embryotoxic effects,
coordination, unconsciousness, coma, particular attention should be paid
and death to the protection of pregnant or
nursing women
INGESTION Effects on the central nervous system, Do not eat, drink, or smoke Rinse mouth; give plenty of
such as dizziness, vomiting, headache, when handling water to drink (no fats, oils,
and unconsciousness tetrachloroethylene milk); induce vomiting in
conscious patients
ROUTE HEALTH HAZARDS PREVENTION AND PROTECTION FIRST AID
REPEATED EXPOSURE
INHALATION Damage to the liver in addition to the Minimize exposure; apply ventilation
effects on the central nervous system or local exhaust; because of the
that are observed after a single exposure possibility of embryotoxic effects,
particular attention should be paid
to the protection of pregnant or
nursing women
4.4.2 Fire hazards
Tetrachloroethylene decomposes in contact with open flames and glowing
surfaces, and when exposed to ultraviolet radiation, with the
formation of harmful gases, such as hydrogen chloride, which forms
mists of hydrochloric acid with moisture, and phosgene.
4.4.3 Prevention
Do not use tetrachloroethylene in the vicinity of a fire, a hot
surface, or during welding. Do not smoke. Fire fighters should use
self-contained breathing apparatus when tetrachloroethylene is
involved in a fire. Keep the compound away from zinc, light metals,
and dinitrogen tetroxide (N2O4).
4.5 Storage
Tetrachloroethylene can be stored in mild steel, cast iron, iron, or
brown glass, tightly-closed containers. Store in well-labelled
containers and separately from zinc, light metals, dinitrogen
tetroxide (N2O4), and foodstuffs, with adequate ventilation across
the floor.
4.6 Transport
No special measures are indicated.
4.7 Spillage and Disposal
4.7.1 Spillage
Collect leaking liquid in sealable containers, absorb spilled liquid
in sand, earth, or vermiculite or similar material, and remove to a
safe place. Do not allow run-off into a sewer. Ensure personal
protection by the use of self-contained breathing apparatus.
4.7.2 Disposal (based on the IRPTC waste disposal file)
Contaminated tetrachloroethylene can be regenerated by distillation.
The residue may be treated further by steam distillation. The
remaining waste should be incinerated after mixing with a combustible
fuel. Assure complete combustion to prevent the formation of phosgene.
An acid scrubber is necessary to remove the haloacids produced. The
haloacids may be recovered from waste gases and reused.
5. INTERNATIONAL CHEMICAL SAFETY CARD
This card should be easily available to all health workers concerned
with, and users of, tetrachloroethylene. It should be displayed at, or
near, entrances to areas where there is potential exposure to
tetrachloroethylene, 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
TETRACHLOROETHYLENE
(ethylene tetrachloride, perchloroethylene)
(Cl2C = CCl2)
PHYSICAL PROPERTIES OTHER CHARACTERISTICS
Relative molecular mass 165.82 Colourless dense liquid with a ethereal odour; the
Appearance colourless, dense liquid compound decomposes in contact with open flames
Odour ether-like and glowing surfaces and under ultraviolet radiation
Odour recognition threshold 30-320 mg/m3 with formation of harmful gases; explosive mixtures
Melting point (°C) -22 are formed with light metals, zinc, and N2O4
Boiling point (°C) 121
Solubility in water (20°C) 150 g/litre
Density (20°C) 1.62 g/ml
Relative vapour density 5.8
Vapour pressure (20°C) 1.9 kPa
Octanol/water partition coefficient 2.86
HAZARDS/SYMPTOMS PREVENTION AND PROTECTION FIRST AID
SKIN: Irritation; redness Minimize exposure by wearing Remove contaminated clothing; wash skin with plenty
protective clothing and gloves of water
EYES: Irritation; redness Wear safety goggles if there Rinse eyes with plenty of water for at least 15 minutes
is a possibility of eye contact
SAMPLE INTERNATIONAL CHEMICAL SAFETY CARD (cont'd).
HAZARDS/SYMPTOMS PREVENTION AND PROTECTION FIRST AID
INHALATION: Irritation of nose and Minimize exposure by use of Fresh air, rest; if breathing has stopped, artificial
system breathing protection; because
of the possibility of embryotoxic
effects, particular attention should
be paid to the protection of
pregnant and nursing women
INGESTION: Effects on the nervous system Do not eat, drink, or smoke Rinse mouth; give plenty of water to drink
when handling the compound (no fats, oils, milk)
GENERAL: Alcoholic beverages may
enhance toxic effects
SPILLAGE STORAGE FIRE AND EXPLOSION
Collect leaking liquid in sealable Store in closed labelled Not flammable
containers; absorb spills in sand, earth, container, away from zinc,
or similar material and remove to a safe light metals, and foodstuffs:
place; ensure personal protection by ensure ventilation across
use of self-contained breathing apparatus the floor
SAMPLE INTERNATIONAL CHEMICAL SAFETY CARD (cont'd).
HAZARDS/SYMPTOMS PREVENTION AND PROTECTION FIRST AID
WASTE DISPOSAL
Regeneration by distillation: waste should National Occupational Exposure Limit: UN: 1897
be incinerated after mixing with a National Poison Control Centre:
combustible fuel; apply acid scrubbing;
assure complete combustion
Note: Do not use the compound in the vicinity of a fire, a hot surface, or during welding. Do not smoke. Do not depend on odour as
a warning of overexposure.
6. HAZARDS FOR THE ENVIRONMENT AND THEIR PREVENTION
When tetrachloroethylene leaches into groundwater, it can persist.
After spills, tetrachloroethylene in aqueous solution can be toxic for
aquatic species.
Avoid contamination of soil, water, and atmosphere by proper methods
of storage, transport, handling, and waste disposal. In case of
spillage, use the methods advised in section 4.7.
Minimize losses to the atmosphere by use of condensation (condensers,
cooling coils) and adsorption (activate carbon) techniques. Keep the
chemical in closed containers.
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
The European Community legislation prohibits the marketing of cosmetic
products containing tetrachloroethylene.
7.3 Labelling, Packaging, and Transport
The European Community legislation requires labelling as a 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: harmful by inhalation and if swallowed; avoid
contact with eyes; keep out of reach of children.
The European Community legislation on labelling solvent preparations
classifies tetrachloroethylene in class II b for the purpose of
determining the label of solvent preparations containing this
substance.
The United Nations Committee of Experts on the Transport of Dangerous
Goods classifies tetrachloroethylene as a poisonous substance (Class
6.1) with minor danger for packing purpose (Packing Group III).
Packing methods and the use of a symbol are recommended (1982 (r)).
The International Maritime Organization also classifies
tetrachloroethylene as a poisonous substance (Class. 6.1) and
recommends package, storage, and labelling methods for maritime
transport in glass bottles, cans, and drums (1977 (r)).
The label recommended by both organizations is:
7.4 Waste Disposal
In the USA, any solid waste (except domestic), if it contains
tetrachloroethylene, 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, when
improperly managed (effective data: 1980). An owner or operator of a
hazardous waste incinerator must achieve 99.99% destruction and
removal efficiency of tetrachloroethylene if it is designated as a
principal organic hazardous constituent in its EPA permit (effective
date: 1981).
Permits are required for discharge of tetrachloroethylene from any
point source into USA waters (effective date: 1982). EPA is required
to, or has, set effluent limitations and pretreatment standards for 21
major industries (1981 (r)).
7.5 Other Measures
The European Community legislation on discharge of dangerous
substances into the aquatic environment prohibits the discharge of
tetrachloroethylene 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 670 mg/m3
Belgium Threshold limit value (TLV) 670 mg/m3
Brazil Acceptable limit (48 h/week) 525 mg/m3 1980 (r)
Bulgaria Maximum permissible concentration (MPC) 10 mg/m3 1971 (r)
Czechoslovakia Maximum allowable concentration (MAC) 1985
-- Time-weighted average 250 mg/m3
-- Ceiling value 1250 mg/rn3
Finland Maximum permissible concentration (MPC) 1982 (r)
-- Time-weighted average 335 mg/m3
German Democratic Maximum allowable concentration (MAC) 1983 (r)
Republic -- Time-weighted average 300 mg/m3
-- Short-term exposure limit (STEL) 900 mg/m3
Germany, Federal Biological tolerance value (BAT) 1250 mg/m3 1985 (r)
Republic of (at end of shift)
-- In blood 1 mg/litre
-- In alveolar air 64 mg/m3
EXPOSURE LIMIT VALUES (cont'd).
Medium Specification Country/ Exposure limit descriptiona Value Effective
organization date
Germany, Federal Maximum work-site concentration (MAK) 1985 (r)
Republic of -- 8-h time-weighted average 345 mg/m3
-- Short-term exposure limit (SIEL) 690 mg/m3
(30 min, 4 × per shift)
Hungary Maximum allowable concentration (MAC) 1978 (r)
-- Time-weighted average 10 mg/m3
-- Short-term exposure limit (STEL) 50 mg/m3
(30 min)
Japan Maximum allowable concentration (MAC) 1985 (r)
-- Time-weighted average 335 mg/m3
Netherlands Maximum limit 1985 (r)
-- Time-weighted average (skin absorption) 240 mg/m3
Poland Maximum permissible concentration (MPC) 1982 (r)
-- Ceiling value 60 mg/m3
Romania Maximum permissible concentration (MPC) 1975 (r)
-- Time-weighted average 400 mg/m3
-- Ceiling value 500 mg/m3
AIR Occupational Sweden Hygienic limit value (HLV) 1985
-- One-day time-weighted average 140 mg/m3
-- Short-term exposure limit (STEL) 350 mg/m3
(15-min time-weighted average)
EXPOSURE LIMIT VALUES (cont'd).
Medium Specification Country/ Exposure limit descriptiona Value Effective
organization date
Switzerland Maximum work-site concentration (MAK) 1984 (r)
-- Time-weighted average for skin 345 mg/m3
absorption
United Kingdom Recommended limit 1985 (r)
-- 8-h time-weighted average 678 mg/m3
-- Short-term exposure limit (STEL) 1000 mg/m3
(10-min time-weighted average)
USA (ACGIH) Threshold limit value (TLV) 1984 (r)
-- Time-weighted average 335 mg/m3
-- Short-term exposure limit (STEL) 1340 mg/m3
(intended)
USA (OSHA) Permissible exposure limit (PEL) 1974
-- Time-weighted average 678 mg/m3
-- Ceiling value 1357 mg/m3
USSR Maximum allowable concentration (MAC) 1977
-- Ceiling value for vapour 10 mg/m3
Yugoslavia Maximum allowable concentration (MAC) 1971 (r)
-- Time-weighted average 10 mg/m3
AIR Ambient Czechoslovakia Maximum allowable concentration (MAC) 1975 (r)
-- Average per day 1 mg/m3
-- Average per 0.5 h 4 mg/m3
EXPOSURE LIMIT VALUES (cont'd).
Medium Specification Country/ Exposure limit descriptiona Value Effective
organization date
USSR Maximum allowable concentration (MAC) 1984
-- Average per day 0.06 mg/m3
-- One time per day 0.5 mg/m3
AIR Emissions Germany, Federal Maximum permissible concentration (MPC) 1975
Republic of -- In air from dry-cleaning premises 30 ppm
WATER Surface USSR Permissible level 20/µg/litre 1983
Drinking- WHO Tentative guideline 10/µg/litre 1983 (r)
a TWA = time-weighted average for one working day (usually 8 h).