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FACT SHEET ON A DRINKING WATER CHEMICAL CONTAMINANT
GENERAL INFORMATION
Synonyms:
• 1,1,1-TCA; Methyl Chloroform; Ethan#,* Methyl-
tricnioromethane
Chemical Description:
• Synthetic organic compound; no natural sources
Properties:
• Clear, volatile liquid
• Non-ftammabie
• Boiling point 74 °C
Production and Use:
• Used as a degreasing solvent in metal industries, a
spot remover and film cleaner, and an additive in
metal cutting oils; also used in the synthesis of other
organic chemicals
• Fungiaae ana solvent in pesticide formulations
• P'oaucnon in 1982 was 600 million pounds—about
70% used in metal cleaning
ENVIRONMENTAL PROFILE
Occurrence:
• Ubiquitous in air at concentrations in the tow parts
per billion rang®
• Common contaminant In ground and surface waters
» About 3% of public drinking water supplies obtained
from well water contain 0.5 ng/L or higher TCA; also
found in drinking water derived from surface water
but at lower levels
Releases;
• Releases to environment in industrialized areas
primarily from volatilization during use as a metal
degreaser; the majority of all TCA produced is
released to the environment
• TCA contaminated with grease and oil has been
disposed by ounat in landfills or dumped on the
ground and in sewers
Environmental Fate:
• Migrates readily to ground water; half life greater
than 6 months in water
• TCA released to surface water migrates-to
atmosphere in few days or weexs
• No significant bioaccumulation in individual animals
or food chains
HEALTH EFFECTS
Humans:
• Acute lung aamage and liver changes usually occur
in fatal cases
• EPA cancer classification: group D, not classifiable
(inadequate evidence of ccrcmcgencity)
Experimental Animals:
• High single oral aoses in rats—depress liver metabolism
and causes sleepiness and death
• Oral dose for 12 weeks in rats—central nervous system
disturbances, reduced boay weignt gem, .rcreased
serum enzyme levels, and death
• Long-term oral exposure for 78 or 103 weexs in rats
ana mice—aecreases body weignt gain arc survival
time
• No reports of reproductive or developmental effects
• A draft study reports liver tumors in mice
• Mutagenic in some in vitro bacterial rests
REGULATORY HISTORY
Existing Standards:
• Clean Air Act (CAA): Registered
• Clean Water Act (CWA): Registered
• Resource Conservation and Recovery Act (RCRA):
Listed
• Supertund (CERCIA): Reportable Quantity 1,000
' pounds
• SAitA: Listed
• Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA): No more than 25% Qt a cemace
formulation can contain TCA
• Toxic Substances Control Act (TSCA): -ventofy
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HEALTH INFORMATION
ANALYTICAL METHODS
Maximum Contaminant Level Goals (MCLG):
• Ncrvenfcrceaci© levels cased soiely on an evaluation
of possible neaith risks and exposure, and taking into
contestation a margin for public safety
• Set at zero for cancer-causing chemicals in wafer
MCLG for TCA - 0.002 mg/l
Maximum Contaminant levels {MCI};
•legally enforceable levels for contaminants in public
drinking water supplies
• Based on health risks associated with the
contaminants, analytical methods for their assay,
and water treatment feasibility and practicality
aspects
MCt for TCA - §.002 mg/l (adopted 7/8/87)
EPA Health Advisories (HA):
• Short-term HAs: Provide acceptable concentrations
of contaminants in waterfor up to 10 day exposures,
primarily to evaluate the public health risk resulting
from an accidental spill or an emergency
contamination situation
• Longer-term HAs: Provide guidance for persistent
water contamination situations to cover a period of
up to 7 years
• Lifetime HAs; Derived m the some way as an MCLG
Health Advisories:
Short-term HA for a child ¦ 35 mg/l
Longer-term HA for a child • 3§ mg/l
Longer-term HA for an adult ¦ 125 mg/l
Lifetime HA » 0,002 mg/l
• Gas chromatography
EPA Method 502
WATER TREATMENT
Permanent Treatment:
Best Available Technology (BAT):
- granular activated caroon adsorption
- aeration
- boiling
SHORT-TERM HAZARD ELIMINATION
• if the drinking water standards are exceeded, install
BAT or use an alternative drinking water supply sucn
as oottied water
• Boiling waterfor 5 minutes effectively removes 96% of
the TCA originally present—potential inhalation
hazard
ADDITIONAL HHP
• State or county health officials can indicate a certified
laboratory for testing
• Experts in the state Department of Environmental
Protection or Natural Resources may also oe of ne-D
• The EPA has toil-free numbers for further information
on drinking water auality, treatment recnnoiogies.
for obtaining Health Advisories, and for other
regulatory information
• EPA Hotlines are available Monday through Friday,
8:30 a.m. to 4:30 p.m. EST:
* Safe Drinking Water: 800-426-4791
• Air Quality: 800-631 -2700
•National Pesticides: 800-858-PEST
•Superfund/RCRA: 800-424-9344
800-343-395$
• For information on the Clean Water Act, call (202)
260-7301
• For information on the Toxic Substances Control Act,
call (202) 554-1404
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