Consumer Factsheet on: 1,1,1-TRICHLOROETHANE
List
of Contaminants
As part of the Drinking Water and Health pages, this fact
sheet is part of a larger publication:
National Primary Drinking Water Regulations
This is a factsheet about a chemical that may be found in some public
or private drinking water supplies. It may cause health problems if found
in amounts greater than the health standard set by the United States Environmental
Protection Agency (EPA).
What is 1,1,1-TCA and how is it used?
1,1,1-Trichloroethane (1,1,1-TCA) is an organic liquid with a chloroform-like
odor. It is largely used as a solvent removing grease from machined metal
products, in textile processing and dyeing and in aerosols.
The list of trade names given below may help you find out whether you
are using this chemical at home or work.
Trade Names and Synonyms:
Chloroethene
Methylchloroform
Aerothene TT
Algylen
Alpha-T
Chlorten
Gemalgene
Genklene
Dowclene
Solvent 111
Trichloran
Inhibisol
Why is 1,1,1-TCA being Regulated?
In 1974, Congress passed the Safe Drinking Water Act. This law requires
EPA to determine safe levels of chemicals in drinking water which do or
may cause health problems. These non-enforceable levels, based solely
on possible health risks and exposure, are called Maximum Contaminant
Level Goals.
The MCLG for 1,1,1-TCA has been set at 0.2 parts per million (ppm) because
EPA believes this level of protection would not cause any of the potential
health problems described below.
Based on this MCLG, EPA has set an enforceable standard called a Maximum
Contaminant Level (MCL). MCLs are set as close to the MCLGs as possible,
considering the ability of public water systems to detect and remove contaminants
using suitable treatment technologies.
The MCL has been set at 0.2 ppm because EPA believes, given present
technology and resources, this is the lowest level to which water systems
can reasonably be required to remove this contaminant should it occur
in drinking water.
These drinking water standards and the regulations for ensuring these
standards are met, are called National Primary Drinking Water Regulations.
All public water supplies must abide by these regulations.
What are the Health Effects?
Short-term: EPA has found 1,1,1-TCA to potentially cause the following
health effects when people are exposed to it at levels above the MCL for
relatively short periods of time: damage to the liver, nervous system
and circulatory system.
Long-term: 1,1,1-TCA has the potential to cause the following effects
from a lifetime exposure at levels above the MCL: liver, nervous system
and circulatory system damage.
How much 1,1,1-TCA is produced and released to the environment?
Demand for 1,1,1-trichloroethane was 705 million lbs. in 1989. 1,1,1-TCA
is likely to enter the environment by evaporation or in wastewater from
its production or use in metal cleaning. It can also enter the environment
in leachates and volatile emissions from landfills.
From 1987 to 1993, according to EPA's Toxic Chemical Release Inventory,
releases to water and land totalled over 1 million lbs. These releases
were primarily from metal fabrication industries. The largest releases
occurred in California and Georgia. The largest direct releases to water
occurred in Utah and Indiana.
What happens to 1,1,1-TCA when it is released to the environment?
1,1,1-TCA will evaporate rapidly from water and soil. It does not bind
to soils nor is it broken down by microbial action, so it may leach to
ground water. It has little tendency to accumulate in aquatic life.
How will 1,1,1-TCA be Detected in and Removed from My Drinking Water?
The regulation for 1,1,1-TCA became effective in 1989. Between 1993
and 1995, EPA required your water supplier to collect water samples every
3 months for one year and analyze them to find out if 1,1,1-TCA is present
above 0.5 ppb. If it is present above this level, the system must continue
to monitor this contaminant.
If contaminant levels are found to be consistently above the MCL, your
water supplier must take steps to reduce the amount of 1,1,1-TCA so that
it is consistently below that level. The following treatment methods have
been approved by EPA for removing 1,1,1-TCA: Granular activated charcoal
in combination with Packed Tower Aeration.
How will I know if 1,1,1-TCA is in my drinking water?
If the levels of 1,1,1-TCA exceed the MCL, 0.2 ppm, the system must
notify the public via newspapers, radio, TV and other means. Additional
actions, such as providing alternative drinking water supplies, may be
required to prevent serious risks to public health.
Drinking Water Standards:
Mclg: 0.2 ppm
Mcl: 0.2 ppm
1,1,1-TCA Releases to Water and Land, 1987 to 1993 (in pounds):
|
Water |
Land |
TOTALS (in pounds) |
222,403 |
812,873 |
Top Six States* |
CA |
0 |
109,070
|
GA |
0 |
73,258
|
AR |
0 |
67,000
|
IN |
15,000 |
46,096
|
VA |
0 |
51,822
|
UT |
40,000 |
0
|
Major Industries |
Gray iron foundries |
1,084 |
76,158
|
Aircraft |
546 |
73,258
|
Manufacturing industries |
1,018 |
72,572
|
Wood furniture |
0 |
53,038
|
Fabricated structural metal |
0 |
51,425
|
Plating, polishing |
6,152 |
41,647
|
Turbines, generators |
40,317 |
966
|
* State totals only include facilities with releases greater than 10,000
lbs.
Learn more about your drinking water!
EPA strongly encourages people to learn more about their drinking water,
and to support local efforts to protect and upgrade the supply of safe
drinking water. Your water bill or telephone books government listings
are a good starting point.
Your local water supplier can give you a list of the chemicals they
test for in your water, as well as how your water is treated.
Your state Department of Health/Environment is also a valuable source
of information.
For help in locating these agencies or for information on drinking water
in general, call: EPAs Safe Drinking Water Hotline: (800)
426-4791.
For additional information on the uses and releases of chemicals in
your state, contact the: Community Right-to-Know Hotline: (800) 424-9346.
List of Contaminants
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