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I used to work (3 months)at Lenkurt Electric in San Carlos, CA (now part of GTE) and we washed electrical parts by hand with TCE daily. No gloves! Stupido me....

Trichloroethylene
ATSDR Public Health Statement, October 1989

What is trichloroethylene?
Trichloroethylene is a colorless liquid at room temperature with an odor similar to ether or chloroform. It is a man-made chemical that does not occur naturally in the environment. Trichloroethylene is mainly used as a solvent to remove grease from metal parts. It is used as a solvent in other ways, too, and is used as a chemical (building block) to make other chemicals.

How might I be exposed to trichloroethylene?
The two main sources of human exposure to trichloroethylene are the environment and the workplace. Trichloroethylene has been found in at least 460 of 1179 hazardous waste sites on the National Priorities List (NPL). Background levels of trichloroethylene can be found in the outdoor air we breathe (30 to 460 parts of trichloroethylene per trillion parts of air) and in many lakes, streams, and underground water used as sources of tap water for homes and businesses. Various federal and state surveys indicate that between 9 and 34% of the water supply sources in the United States may be contaminated with trichloroethylene. Water supplies that are contaminated typically contain an average of 1 to 2 parts of trichloroethylene per billion parts of water or less. An important source of environmental release of trichloroethylene is evaporation to the atmosphere from work done to remove grease from metal. In addition, at places where wastes are disposed, trichloroethylene is released to the air by evaporation and to underground water when it passes through the soil.
Trichloroethylene can also be released into the environment through:

Evaporation from adhesive glues, paints, coatings, and other chemicals;

Release of trichloroethylene and chemicals containing it, when it is made;

Air-cleaning processes at publicly owned waste treatment plants that receive wastewater containing trichloroethylene; and

Burning of community and hazardous waste.

Some consumer products that may contain trichloroethylene are:

Typewriter correction fluids, paint removers and paint strippers, adhesive glues, spot removers, cleaning fluids for rugs, and metal cleaners.
How does trichloroethylene get into my body?
Trichloroethylene can enter the body when a person breathes air or drinks water containing it. Trichloroethylene can also enter the body through the skin when it comes in contact with it.

How can trichloroethylene affect my health?
Dizziness, headache, slowed reaction time, sleepiness, and facial numbness have occurred in workers breathing trichloroethylene or in people who use trichloroethylene-containing products in small, poorly ventilated areas. These effects on the central nervous system have also been seen in people who drank several ounces of undiluted trichloroethylene. Irritation of the eyes, nose, and throat can also occur under these conditions. More severe effects on the central nervous system, such as unconsciousness and possibly death, can occur from drinking or breathing higher levels of trichloroethylene. In general, the less severe central nervous system effects that result from one or several exposures to trichloroethylene disappear when exposure ends.
Some health effects may persist in persons following long-term exposure to trichloroethylene. This information is based largely on animal studies. For example, studies in animals show that ingesting or breathing levels of trichloroethylene that are higher than typical environmental levels can produce nervous system changes; liver and kidney damage; effects on the blood; tumors of the liver, kidney, lung, and male sex organs; and possibly cancer of the tissues that form the white blood cells (leukemia). Results of a few studies in pregnant animals exposed to trichloroethylene in air or in food showed effects on unborn animals or on newborns. Drinking alcohol can make people more susceptible to liver and kidney injury from trichloroethylene.

At present, information is not sufficient to determine whether cancer or the effects on the unborn seen in animals following exposure to trichloroethylene may also occur in humans. The International Agency for Research on Cancer has determined that trichloroethylene is not classifiable as to its carcinogenicity to humans.

Is there a medical test to determine if I have been exposed to trichloroethylene?
Recent or ongoing exposures to trichloroethylene can be determined by measuring trichloroethylene in the breath. Another way of determining whether exposure to trichloroethylene has occurred is by measuring a number of breakdown products (metabolites) of trichloroethylene in the urine or blood. Neither of these tests is routinely available at your doctor's office. Because one of the breakdown products, trichloroacetic acid, is removed very slowly from the body, it can be measured in the urine for up to about 1 week following trichloroethylene exposure. It must be noted, however, that exposure to other chemicals can produce the same breakdown products in the urine and blood. Therefore, these methods cannot tell you if you have been exposed only to trichloroethylene.

What levels of exposure have resulted in harmful health effects?
The graphs on the following pages show the link between exposure to trichloroethylene and known health effects. In the first set of graphs, labeled "Health effects from breathing trichloroethylene," (Fig. 1.1), exposure is measured in parts of trichloroethylene per million parts of air (ppm). In the second set of graphs, the same relationship is represented for the known "Health effects from ingesting trichloroethylene" (Fig. 1.2). Exposures are measured in milligrams of trichloroethylene per kilogram of body weight per day (mg/kg/day). In all graphs, effects in animals are shown on the left side and effects in humans are shown on the right.
The first column in Figs. 1.1 and 1.2, labeled "Short-Term Exposure," refers to known health effects in laboratory animals and humans from exposure to trichloroethylene for 2 weeks or less. The column labeled "Long-Term Exposure" refers to trichloroethylene exposures of longer than 2 weeks. The levels marked on the graphs as "minimal risk for effects other than cancer" reflect estimates of levels of exposure at which no adverse effects are expected to occur. These levels are based on information on animals.

Toxic Effects Other Than Cancer--Figure 1.1 shows that short-term and long-term exposures to air containing about 50 ppm or more of trichloroethylene have produced harmful effects in both animals and humans. Figure 1.2 shows that ingesting (drinking) the equivalent of 240 mg (less than a spoonful) of trichloroethylene per kg of body weight (kg = 2.2 pounds) for 2 weeks produced effects in the liver of animals. Drinking similar amounts over longer periods of time caused effects on unborn animals and the kidney as well as on the liver.

Cancer--From available information on animals, the Environmental Protection Agency (EPA) has estimated that breathing air containing 1 ppm trichloroethylene every day for 70 years may place as many as 93 persons in a population of 10,000 (or 93,000 persons in a population of 10,000,000) at risk of developing cancer. EPA has also estimated that drinking water containing 1 ppm trichloroethylene every day over a lifetime may place as many as 3 persons in a population of 10,000 (or 3,200 persons in a population of 10,000,000) at risk of developing cancer. It should be noted that these risk levels for humans are plausible upper-limit estimates based on information obtained from animal studies. Actual risk levels are unlikely to be higher and may be lower.

What recommendations has the federal government made to protect human health?
EPA has established a drinking water standard of 5 parts of trichloroethylene per billion parts of water (ppb). This level became effective on January 9, 1989, and applies to community water systems and those which serve the same 25 or more persons for at least 6 months.
Trichloroethylene levels in the workplace are regulated by the Occupational Safety and Health Administration (OSHA). The occupational exposure limit for an 8-hour workday, 40-hour workweek is an average concentration of 50 ppm in air. The 15-minute average exposure, which should not be exceeded at any time during a workday, is 200 ppm. The OSHA standards do not take into consideration the cancer-causing potential of trichloroethylene. EPA requires industry to report spills of 1,000 pounds or more of trichloroethylene. It has been proposed that this level be reduced to 100 pounds.

Where can I get more information?
If you have more questions or concerns, please contact your state health or environmental department or:

Agency for Toxic Substances and Disease Registry

Division of Toxicology

1600 Clifton Road, E-29

Atlanta, Georgia 30333