United States
Environmental Protection
Agency
Office of Water
4601
EPA 811-F-95-0040-T
October 1995
National Primary Drinking
Water Regulations
Tetrach loroethy lene
CHEMICAL/ PHYSICAL PROPERTIES
CAS NUMBER: 127-18-4
COLOR/ FORM/ODOR:
Colorless liquid with mildy sweet,
chloroform-like odor; available in many
forms, from worm pills to dry-cleaning
grades containing various stabilizers.
M.P.: -19° C B.P.: 121° C
VAPOR PRESSURE: 18.47 mm Hg at 25° C
OCTANOL/WATER PARTITION (Kow):
. Log Kow = 3.40
DENSITY/SPEC. GRAV.: 1.62 at 20° C
SOLUBILITY: 0.15 g/L of water at 25° C;
Slightly soluble in water
SOIL SORPTION COEFFICIENT:
Koc = 210 (exp.) to 238 (est.); low to
moderate mobility in soil
ODOR/TASTE THRESHOLDS: Taste thresh-
old in water is 0.3 mg/L
BlOCONCENTRATION FACTOR:
BCFs of 39 to 49 reported in fish; not
expected to bioconcentrate in aquatic
organisms.
HENRY'S LAW COEFFICIENT: N/A
TRADE NAMES/SYNONYMS:
Ethylene tetrachloride, Perchloroethyl-
ene, PCE, Ankilostin, Didakene,
Fedal-un, Nema, Perclene, Persec,
Tetlen, Tetracap, Tetraleno, Tetropil,
Antisal 1, Dow-per, Perawin, Perchlor,
Percosolv, Perk, Perklone, Tetraguer,
Tetralex, Tetravec
DRINKING WATER STANDARDS
MCLG: zero mg/L
MCL: 0.005 mg/L
HAL(child): 1- to 10-day: 2 mg/L
Longer-term: 1 mg/L
HEALTH EFFECTS SUMMARY
Acute: EPA has found tetrachloroethylene to poten-
tially cause the following health effects from acute expo-
sures at levels above the MCL: detrimental effects to
liver, kidney, and central nervous system.
Drinking water levels which are considered "safe" for
short-term exposures: Fora 10-kg (22 Ib.) child consum-
ing 1 liter of water per day: a one- to ten-day exposure to
2 mg/L; upto a 7-year exposure to 1 mg/L.
Chronic: Tetrachloroethylene has the potential to
cause the following health effects from long-term expo-
sures at levels above the MCL: detrimental effects to
liver, kidney, and central nervous system.
Cancer: There is some evidence that tetrachloroeth-
ylene may have the potential to cause cancer from a
lifetime exposure at levels above the MCL.
USAGE PATTERNS
Production of tetrachloroethylene has decreased: from
736 million IDS. .in 1978 to 405 million Ibs in 1986.
In 1989 it was estimated that industries consumed
tetrachloroethylene as follows: Dry cleaning and textile
processing, 50%; chemical intermediate (mostly fluoro-
carbon F-113), 28%; industrial metal cleaning, 9%; ex-
ports, 10%; other, 3%.
The greatest use of tetrachloroethylene is in the textile
industry for processing, finishing, sizing, and as a compo-
nent of aerosol dry-cleaning products.
Other uses include: an intermediate in the synthesis of
Tbxrc RELEASE INVENTORY -
RELEASES TO WATER AND LAND: 1987
TOTALS (in pounds)
Top Seven States"
LA
SC
NH
NC
IL
TX
OH
Major Industries*
Alkalis, chlorine
Leather tanning.finishing
Cotton fabric finishing
Misc textile finishing
Knit outwear mills
Misc. apparel, access.
Transportation Equip.
Ammunition
* Water/Land totals only
Water
297,602
23,639
104,728
62,150
42,192
0
36,144
0
63,472
62,150
51,577
48,082
45,808
0
3,750
0
include facilities with
TO 1993
Land
750,104
610,518
0
0
13,102
40,500
720
32,170
611,242
0
0
2,000
0
40,500
27,000
20,575
releases
greater than a certain amount - usually 1000 to 10,000 Ibs.
October 1995
Technical Version
-------
fluorocarbons, an insulating/cooling fluid in electric trans-
formers, in typewriter correction fluids, as veterinary
medication against worms, once used as grain protectant/
fumigant.
RELEASE PATTERNS
Major releases of tetrachloroethylene are: via vapor-
ization losses from dry cleaning and industrial metal
cleaning; wastewater, particularly from metal finishing,
laundries, aluminum forming, organic chemical/plastics
manufacturing and municipal treatment plants. It is also
estimated that emissions account for approximately 90%
of the tetrachloroethylene produced in the United States.
Water pollution can occur from tetrachloroethylene
leaching from vinyl* lers in asbestos-cement water pipe-
lines for water distribution, and during chlorination water
treatment, where it can be formed in small quantities.
From 1987 to 1993, according to EPA's Toxic Chemi-
cal Release Inventory, tetrachloroethylene releases to
land and water totalled over 1 million Ibs., of which about
75 percent was to land.
These releases were primarily from alkali and chlorine
industries which use tetrachloroethylene in making other
chemicals. The largest releases occurred in Louisiana
and South Carolina.
ENVIRONMENTAL FATE
If PCE is released to soil, it will be subject to evapora-
tion into the atmosphere and to leaching to the groundwa-
ter. Tetrachloroethylene was slightly adsorbed on sand
and clay minerals. The Henry's adsorption coefficients
were approximately in proportion to the organic content
of the soil samples. Based on the reported and estimated
Koc's (209 to 1685), tetrachloroethylene will beexpected
to exhibit low to medium mobility in soil and therefore may
leach slowly to the groundwater.
There is evidence that slow biodegradation of PCE
occurs under anaerobic conditions when the microor-
ganisms have been acclimated. In experiments using
continuous-flow laboratory methanogenic column with
well acclimated mixed cultures and a 2-day detention
time, there was an average PCE removal rate of 76%.
Removal of 86% PCE occurred in a methanogenic biofilm
column (8 weeks of activation followed by 9-12 weeks
ofacclimation). In a microcosm containing muck from an
aquifer recharge basin, 72.8% loss was observed in 21
days against 12-17% in controls. In one field ground
water recharge project, degradation was observed in the
50 day recharge period.
If PCE is released to water, it will be subject to rapid
volatilization with estimated half-lives ranging from <1
day to several weeks. Measured volatilization half-lives
in a mesocosm simulating Narraganset Bay, Rl were 11
days in winter, 25 days in spring, and 14 days in summer.
PCE will not be expected to significantly biodegrade in
water or adsorb to sediment. PCE will not be expected to
significantly hydrolyze in soil or water under normal
environmental conditions (half-life 9 months at 25 deg C).
If PCE is released to the atmosphere, it will exist mainly
in the gas-phase and it will be subject to photooxidation
with estimates of degradation time scales ranging from
an approximate half-life of 2 months to complete degra-
dation in an hour. Some of the PCE in the atmosphere
may be subject to washout in rain based on the solubility
of PCE in water and the fact that PCE has been detected
in rain.
Based on the reported and estimated BCF's, tetrachlo-
roethylene will not be expected to significantly biocon-
centrate in aquatic organisms. BCFs of 39 to 49 were
measured in fish; a BCF of 226 was estimated from
octanol water partition coefficient.
Major human exposure is from inhalation of contami-
nated urban air, especially near point sources such as dry
cleaners, drinking contaminated water from contami-
nated aquifers and drinking water distributed in pipelines
with vinyl liners, and inhalation of contaminated occupa-
tional atmospheres in metal degreasing and dry cleaning
industries.
OTHER REGULATORY INFORMATION
MONITORING:
FOR GROUND/SURFACE WATER SOURCES:
INITIAL FREQUENCY- 4 quarterly samples every 3 years
. REPEAT FREQUENCY- Annually after ,1 year of no detection
TRIGGERS - Return to Initial Freq. if detect at > 0.0005 mg/L
ANALYSIS:
REFERENCE SOURCE
EPA 600/4-88-039
METHOD NUMBERS
502.2; 524.2; 551
TREATMENT:
BEST AVAILABLE TECHNOLOGIES
Granular Activated Charcoal and Packed Tower, Aeration
FOR ADDITIONAL INFORMATION:
* EPA can provide further regulatory and other general information:
• EPA Safe Drinking Water Hotline - 800/426-4791
* Other sources of toxicological and environmental fate data include.
• Toxic Substance Control Act Information Line - 202/554-1404
Toxics Release Inventory, National Library of Medicine - 301/496-6531
• Agency for Toxic Substances and Disease Registry - 404/639-6000
October 1995
Technical Version
Page 2
------- |