1.1 What is 1,1-dichloroethane? |
1.2 How might I be exposed to 1,1-dichloroethane? |
1.3 How can 1,1-dichloroethane enter and
leave my body? |
1.4 How can 1,1-dichloroethane affect
my health? |
1.5 What levels of exposure have resulted
in harmful health effects? |
1.6 Is there a medical test to determine
whether I have been exposed to 1,1-dichloroethane? |
1.7 What recommendations has the federal
government made to protect human health? |
1.8 Where can I get more information? |
References |
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December 1990 |
Public Health Statement |
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1,1-Dichloroethane |
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This Public Health Statement is the
summary chapter from the Toxicological
Profile for 1,1-dichloroethane. It is one in a series
of Public Health Statements about hazardous substances and
their health effects. A shorter version, the ToxFAQs™,
is also available. This information is important because this
substance may harm you. The effects of exposure to any hazardous
substance depend on the dose, the duration, how you are exposed,
personal traits and habits, and whether other chemicals are
present. For more information, call the ATSDR Information
Center at 1-888-422-8737.
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This Statement was prepared to give you
information about 1,1-dichloroethane and to emphasize the
human health effects that may result from exposure to it.
The Environmental Protection Agency (EPA) has identified 1,177
sites on its National Priorities List (NPL). 1,1-Dichloroethane
has been found at 189 of these sites. However, we do not know
how many of the 1,177 NPL sites have been evaluated for 1,1-dichloroethane.
As EPA evaluates more sites, the number of sites at which
1,1-dichloroethane is found may change.
The information is important for you
because 1,1-dichloroethane may cause harmful health effects
and because these sites are potential or actual sources of
human exposure to 1,1-dichloroethane. When a chemical is released
from a large area, such as an industrial plant, or from a
container, such as a drum or bottle, it enters the environment
as a chemical emission. This emission, which is also called
a release, does not always lead to exposure.
You can be exposed to a chemical only
when you come into contact with the chemical. You may be exposed
to it in the environment by breathing, eating, or drinking
substances containing the chemical or from skin contact with
it. If you are exposed to a hazardous substance such as 1,1-dichloroethane
several factors will determine whether harmful health effects
will occur and that the type and severity of those health
effects will be. These factors include the dose (how much),
the duration (how long), the route or pathway by which you
are exposed (breathing, eating, drinking, or skin contact),
the other chemicals to which you are exposed, and your individual
characteristics such as age, sex, nutritional status, family
traits, life style, and state of health.
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1.1
What is 1,1-dichloroethane? |
1,1-Dichloroethane is a colorless, oily,
man-made liquid. It evaporates quickly at room temperature
and has an odor like ether. 1,1-Dichloroethane burns easily.
When 1,1-dichloroethane is released to the environment, it
usually exists as a vapor rather than a liquid. It is used
primarily to make 1,1-trichloroethane and a number of other
chemicals. It is also used to dissolve other substances
such as paint, varnish and finish removers, and to remove
grease. 1,1-Dichloroethane was used as a surgical anesthetic,
but is no longer.
Almost all of the 1,1-dichloroethane
from industrial sources that is released goes into the air.
1,1-Dichloroethane can also be found in the environment as
a breakdown product of 1,1,1-trichloroethane in landfills
where air comes in contact with 1,1,1-trichloroethane. 1,1-Dichloroethane
not dissolve easily in water. The small amounts released to
water can evaporate easily into the air. 1,1-Dichloroethane
remains as a vapor in the air for about 2 months and dissolved
in water for about 5 days. The vapor in air can be washed
out by rain or broken down by sunlight. 1,1-Dichloroethane
in water will evaporate. Small amounts of 1,1-dichloroethane
released to soil can also evaporate into the air or move through
the soil to enter groundwater. It is not known how long 1,1-dichloroethane
remains in the soil.
Although it does not dissolve easily
in water, low levels can be found in water.
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1.2
How might I be exposed to 1,1-dichloroethane? |
You can be exposed to 1,1-dichloroethane
by breathing air containing its vapors in the outdoor air
or in your workplace, or by drinking water contaminated with
it. Releases from industrial processes are the main source
of this chemical in the air. Some members of the general population
may be exposed to low levels of 1,1-dichloroethane from this
source (0.08-0.14 parts per billion [1 part 1,1-dichloroethane
per 1 billion parts of air, or ppb]).
Levels in this range have been measured
around industrial plants in Magna, Utah (0.082 ppb); Iberville,
Louisiana (0.12 ppb); Deer Park, Texas (0.14 ppb); and Baton
Rouge (0.058 ppb) and Geismary, Louisiana (0.14 ppb). You
may be part of a much smaller population of workers who could
be exposed to higher levels of 1,1-dichloroethane in your
workplace, if you are employed in the chemical, rubber and
plastic, electrical, or oil and gas industries. However, since
current levels of production and use are not known, it is
difficult to predict how often exposure might occur from these
sources of 1,1-dichloroethane.
Exposure can also occur near sites where
the chemical was improperly disposed of or spilled on the
ground. The average concentration of 1,1-dichloroethane in
the air across the United States is reported to be 55 parts
of 1,1-dichloroethane per one trillion parts of air (ppt).
These ambient levels may be from chlorinated water or building
materials.
The air levels of 1,1-dichloroethane
are usually lower in rural areas and higher in industrialized
areas. Higher levels have been found in the air around some
small sources of release, such as hazardous waste sites.
1,1-Dichloroethane has been found in
drinking water (that is, water that has usually been treated
and that comes out of your tap) in the United States at levels
that range from trace amounts to 4.8 parts of 1,1-dichloroethane
per one billion parts of water (ppb). 1,1-Dichloroethane has
not been detected in any surface water samples from rivers,
lakes, or ponds. No information is available on background
levels of 1,1-dichloroethane in soil or food.
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1.3
How can 1,1-dichloroethane enter and leave my body? |
1,1-Dichloroethane can enter your body
if you breathe contaminated air or drink contaminated water.
1,1-Dichloroethane is believed to rapidly enter your body
when it is breathed or swallowed. It is not known what factors
affect how quickly 1,1-dichloroethane enters your body. Studies
in animals show that it is likely that 1,1-dichloroethane
can also enter your body through your skin.
The most common way you could be exposed
to 1,1-dichloroethane released from hazardous waste sites
would be by breathing contaminated air around the site. Soil
and water in and around hazardous waste sites are not likely
to contain high concentrations of 1,1-dichloroethane because
it escapes quickly into the air. Therefore, though this route
of exposure cannot be ruled out, exposure of the skin from
soil or water contaminated with 1,1-dichloroethane is much
less likely.
Experiments in animals indicate that
the 1,1-dichloroethane that is inhaled or swallowed may go
to many organs of the body, depending on the amount taken
in. However, most of the 1,1-dichloroethane taken in is usually
removed unchanged from the body in the breath within 2 days.
A small part of the 1,1-dichloroethane taken in is broken
down, and these breakdown products are quickly removed in
the breath or urine.
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1.4
How can 1,1-dichloroethane affect my health? |
Reliable information on how 1,1-dichloroethane
affects the health of humans is not available. Because brief
exposures to 1,1-dichloroethane in the air at very high levels
have caused death in animals (16,000 ppm), it is likely that
exposure to such high levels of 1,1-dichloroethane in the
air can also cause death in humans.
Some studies in animals have shown that
1,1-dichloroethane can cause kidney disease after long-term,
high-level exposure in the air. 1,1-Dichloroethane caused
cancer in animals given very high doses (over 3,000 mg/kg/day)
by mouth for a lifetime. Delayed growth was observed in the
offspring of animals who breathed high concentrations of 1,1-dichloroethane
during pregnancy.
The severity of these effects may increase
when people or animals are exposed to increased levels of
1,1-dichloroethane. Since these effects were seen in animals
at high doses, it is also possible that they could occur in
humans exposed to high levels of 1,1-dichloroethane. However,
we have no information to indicate that these effects do occur
in humans.
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1.5
What levels of exposure have resulted in harmful health effects? |
There is no reliable information on what
levels of exposure to 1,1-dichloroethane have resulted in
harmful health effects in people.
In animals, birth defects were seen in
the offspring of rats exposed to high levels (1,750 parts
per million [ppm]) in air.
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1.6
Is there a medical test to determine whether I have been exposed
to 1,1-dichloroethane? |
Tests are available that measure 1,1-dichloroethane
in urine, blood, breath and body tissues. Because urine, blood,
and breath samples are easily obtained, these samples are
examined to determine if a person has been exposed to 1,1-dichloroethane.
These tests are not routinely available at a doctor's office
and would require special equipment for sampling and detection
of the compound. Since most of the 1,1-dichloroethane that
is taken into the body leaves within two days, these tests
must be done soon after exposure occurs.
Although these tests can confirm that
a person has been exposed to 1,1-dichloroethane, it is not
yet possible to use the test results to predict the type or
severity of any health effects that might occur or the level
of exposure that may have occurred. Because exposure to 1,1-dichloroethane
at hazardous waste sites is likely to include exposure to
other similar chemicals at the some time, levels of 1,1-dichloroethane
measured through these types of medical tests may not reflect
exposure to 1,1-dichloroethane alone.
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1.7
What recommendations has the federal government made to protect
human health? |
There are no regulatory standards or
advisories for 1,1-dichloroethane in drinking water and food.
The Environmental Protection Agency (EPA) has determined that
any release to the environment in excess of 1,000 pounds should
be reported. Rules and regulations have been developed to
protect individuals from the potential health effects of 1,1-dichloroethane
in air. The American Conference of Governmental Industrial
hygienists (ACGIH) has set a threshold limit value (TLV) of
810 mg/m³ (200 ppm) 1,1-dichloroethane in workroom air
to protect workers during an 8-hour shift over a 40-hour work
week. The Occupational Safety and Health Administration (OSHA)
has issued a permissible exposure limit (PEL) of 400 mg/m³,
(98.9 ppm).
The federal recommendations have been
updated as of July 1999.
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1.8 Where can I get more information? |
If you have any more questions or concerns, please contact
your community or state health or environmental quality department or:
Agency for Toxic Substances and Disease Registry
Division of Toxicology
1600 Clifton Road NE, Mailstop F-32
Atlanta, GA 30333
Information line and technical assistance:
Phone: 888-422-8737
FAX: (770)-488-4178
ATSDR can also tell you the location of occupational and environmental health
clinics. These clinics specialize in recognizing, evaluating, and treating illnesses
resulting from exposure to hazardous substances.
To order toxicological profiles, contact:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Phone: 800-553-6847 or 703-605-6000
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References
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Agency for Toxic Substances and Disease
Registry (ATSDR). 1990. Toxicological
profile for 1,1-dichloroethane. Atlanta, GA: U.S. Department
of Health and Human Services, Public Health Service.
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