HEXACHL#R#ETHANE
PROFILE OF DRINKING WATER CONTAMINANTS FOR EMERGENCY RESPONSE
GENERAL INFORMATION
Hexachloroethane is used by the military in the
production of pyrotechnic devices and screening
smokes. It is commercially used as a pressure lubri-
cant, in fluorocarbon production, and in rubber,
insecticide, paint, and fire extinguishing formulations.
Most hexachloroethane used in the United States is
imported with an annual import of about 1.6 million
pounds between 1973-1979. U.S. production is gener-
ally limited to its formulation as a co-product in the
manufacture of other chlorinated ethanes. Average
annual (1966-1977) use of hexachloroethane for mili-
tary smoke devices was 193,000 pounds. Hexachloro-
ethane wastes occur in effluents from chemical plants
and have been found in ground water, soil, and air.
The environmental fate of hexachloroethane is
not well established, but experimental data indicate
that it volatilizes to the atmosphere from water and
soil. In the atmosphere, it is generally stable. It can
be biotransformed, will adsorb to sediments, and
bioaccumulates.
PHARMACOKINETICS
Hexachloroethane is absorbed following ingestion,
inhalation, or dermal contact in rats, mice, rabbits, and
sheep. It preferentially accumulates in body fat It is ex-
creted primarily in expired air and urinary excretion
plays a minor role. Following oral intake, it is metabo-
lized mainly to tetrachloroethylene in sheep, and to
trichloroethanol and trichloracetic acid in rats and mice.
Reduction and dechlorination is proposed as the main
mode of metabolism of hexachloroethane.
HEALTH EFFECTS
Humans
Ingestion of hexachloroethane by two persons
over a 3-4 day period reduced their skin sensitivity.
Data from occupational health surveys indicate
that hexachloroethane adversely effects the central
nervous system (typically, workers cannot close their
eyes). Direct exposure to hexachloroethane fumes
causes eye irritation, inflammation, tearing, and
photophobia.
HEALTH EFFECTS
Experimental Animals
Acute oral toxicity in rats and guinea pigs is asso-
ciated with tremor, ataxia, gasping, and red exudate
around the eyes. Single oral doses in sheep produced
liver toxicity.
Hexachloroethane is a mild skin irritant in rabbits
and causes eye swelling and discharge, corneal opac-
ity, and iritis. No skin sensitization was observed in
guinea pigs.
Decreased body weight gain, increased liver and
kidney weights, and liver and kidney histopathology
were seen in rabbits given oral doses for 12 days and
rats similarly exposed for 16 days. Additional adverse
kidney effects are observed in male rats.
In a 16-week feeding study with rats,
histopathological lesions were evident in the kidneys
of males as well as some liver lesions.
No reproductive studies were found. Although
hexachloroethane was not shown to be teratogenic,
fetotoxic effects were indicated. Mutagenic tests in
bacterial assays were negative.
The toxic effects following 78 weeks of oral ex-
posure were tumors of the testes in male rats, and
liver carcinomas in mice. Toxic effects seen in a 2-
year oral study with rats included cancer of the kid-
neys in males.
OTHER CRITERIA, ANALYSES, AND
TREATMENT TECHNOLOGIES
The American Conference of Governmental In-
dustrial Hygienists (ACCIH) 8-hour time-weighted
average Threshold Limit Value for exposure to hexa-
chloroethane is 9.7 mg/m3. The Occupational Safety
and Health Administration (OSHA) Permissible Expo-
sure Limit is 10 mg/m5.
Methods available for the analysis of hexachloro-
ethane involve extraction with an organic solvent fol-
lowed by various modifications of the gas-liquid
chromatography technique.
No information was found regarding technologies
for the removal of hexachloroethane from water.
However, in studies of environmental fate, hexachlo-
roethane in water has been biotransformed under
aerobic and anaerobic conditions.

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Empirical Formula
Synonyms
'\
CAS Number
Physical State
Molecular Weight
Boiling Point
Melting Point
Density
Vapor Pressure
Solubility
Health Effects Data and Advisory Values
Genotoxicity
Hexachloroethane did not induce genetic effects in in vitro Salmonella
typhimurium and Saccharomyces cerevisiae assays.
Reproductive and
Developmental Effects
No reproductive studies were found. A developmental effects study in rats
orally exposed to hexachloroethane indicated that it is not teratogenic, al-
though gestation time was reduced, the number of viable fetuses was de-
creased, and there was an increase in fetal resorption.
Cancer Classification
EPA Group C, possible human carcinogen, based on hepatocellular carcino-
mas in B6C3F, mice of both sexes.
Reference Dose (RfD)
0.0013 mg/kg/day

Drinking Water
Equivalent Level (DWEL)
0.035 mg/L

Health Advisory Values
One-Day
Ten-Day
Longer-Term (child)
Longer-Term (adult)
Lifetime
5 mg/L
5 mg/L
0.13 mg/L
0.45 mg/L
0.001 mg/L
This summary was developed using information from the Drinking Water Health Advisory.
For further information contact EPA's Office of Science and Technology at (202) 260-7571.
Office of Science and Technology
Office of Water
U.S. Environmental Protection Agency
401 M Street, SW
Washington, DC 20460
June 17,1991
Physical and Chemical Properties
c ci
Carbon hexachloride, Perchloroethane, Ethanehexachloride, 1,1,1,2,2,2-Hexa-
chloroethane, Hexachlorethylene, Avlothane, Distokal, Distopan, Distopin,
Egitol, Falkitol, Fasciolin, Hexoram, Phenohep
67-72-1
White crystalline solid	CI CI
236.74	II
186.8°C	CI—C —C —CI
186.8-187.4°C (sublimes)	' '
2.091 at 20°C	Cl Cl
0.4 mmHg at 20°C
In water: 50 mg/L at 22°C. Very soluble in alcohol and ether. Soluble in
benzene, chloroform, and oils.

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