Trichloroethylene is primarily used as a solvent to remove greases from metal parts. As a solvent or as a component of solvent blends trichloroethylene is used with adhesives, lubricants, paints, varnishes, paint strippers, pesticides, and cold metal cleaners. It is used to make other chemicals (pharmaceuticals, polychlorinated aliphatics, flame retardants, and insecticides). It is used as an extraction solvent for greases, oils, fats, waxes and tars. The textile industry uses it to scour cotton, wool and other fabrics, and in waterless dying and finishing. It is used as a refrigerant for low temperature heat transfer.
Substance name: Trichloroethylene
CASR number: 79-01-6
Molecular formula: C2HCl3
Synonyms: Ethinyl trichloride; Acetylene trichloride; ethylene trichloride; triiecene; 1,1,2-Trichloroethylene; Tri; TCE; trichloroethene; Trichloran; Trichloren; 1,2,2-trichloroethylene; anamenth; benzinol
Trichloroethylene is a colourless, liquid with a sweet odour, and a sweet burning taste.
Melting Point: -73°C
Boiling Point: 86.7°C
Vapour Density: 4.53
Specific Gravity: 1.456
Trichloroethylene is nonflammable. It is slightly soluble in water, and soluble in most other organic solvents.
The National Pollutant Inventory (NPI) holds data for all sources of Trichloroethylene in Australia.
Trichloroethylene is a central nervous system depressant and has been used as an anaesthetic, for surgery. Some people intentionally inhale it for its narcotic properties. Exposure to moderate amounts of trichloroethylene may cause headaches, loss of balance, and tremors. Larger exposures will cause dizziness or sleepiness, and may cause unconsciousness at very high levels. Very large exposures may cause irreversible cardiac problems, nerve and liver damage, and death. It is mildly irritating to the eyes and nose, and throat. Chronic (long-term) exposures to trichloroethylene have also been shown to cause nausea, intolerance to fatty foods, respiratory irritation, renal (kidney) toxicity, and immune system depression. Alcohol consumption increases the toxicity of trichloroethylene and may cause 'degreaser's flush', red blotches on the skin. The International Agency for Research on Cancer classified trichloroethylene as a 'probable human carcinogen'.
Entering the body
Trichloroethylene will enter the body if we breathe in contaminated air, or water that has been contaminated. It can also pass through the skin.
Workers in the industries that use or produce trichloroethylene are at risk of exposure. Consumers can be exposed to trichloroethylene by exposure to air from production and processing facilities using trichloroethylene, or drinking water from contaminated water. Consumers may also be exposed to trichloroethylene when using consumer products containing trichloroethylene, especially if there is not good ventilation, or by skin contact. Because trichloroethylene is used in many consumer products, short-term indoor concentrations may be elevated above the levels considered safe for workers.
Workplace exposure standards
Safe Work Australia sets the workplace exposure standard for trichloroethylene through the workplace exposure standards for airborne contaminants:
- Maximum eight hour time weighted average (TWA): 10 parts per million (54 mg/m3)
- Maximum short term exposure limit (STEL): 40 parts per million (216 mg/m3)
These standards are only appropriate for use in workplaces and are not limited to any specific industry or operation. Make sure you understand how to interpret the standards before you use them.
Drinking water guidelines
According to the Australian Drinking Water Guidelines, data are inadequate to set a guideline value for trichloroethylene in drinking water.
What is the effect on our environment of high concentrations of trichloroethylene? Trichloroethylene will exist as a gas if released to the atmosphere. It dissolves when mixed with water. In the air it is reacted into other chemicals, in the water and soil bacteria break it down. It has moderate acute (short-term) toxicity on aquatic life. It has moderate chronic (long-term) toxicity to aquatic life. Chronic and acute effects on plants, birds or land animals have not been determined. Trichloroethylene does bioaccumulate to a limited extent. The concentration of trichloroethylene in the tissues of fish are expected to be higher than the concentration of trichloroethylene in the water from which the fish was taken.
Entering the environment
Industrial emissions of trichloroethylene can produce elevated concentrations in the atmosphere around the source. Because of its short life expectancy in the atmosphere trichloroethylene is expected to be confined to the local area within which it is emitted. Since it does not bind to soil well, trichloroethylene that makes its way into the ground may move through the ground and enter groundwater (bore water).
Where it ends up
Trichloroethylene enters the air during production, use and transporting it. In the air it will break down into other chemicals (phosgene, formyl chloride, and chlorine atoms - which leads to the creation of hydrochloric acid) in a six to forty days. When released to the soil it will either evaporate or leach into the ground water (bores). It will also quickly evaporate if released to surface water. According to the World Health Organisation trichloroethylene is found to be widely distributed in surface water, rain water, and bore water. In the soil and water bacteria will break it down. In the water it will break down in 2 to 10 days. It does not deposit on the bottom of rivers or lakes.
No national guidelines.
Sources of emissions
The primary sources of trichloroethylene emissions are the industries that manufacture it or use it in production, such as the chemical industry, rubber manufacturers, the pharmaceutical industry, the semiconductor industry, heavy equipment manufacturing, iron and steel manufacturing, pulp and paper manufacture (for de-inking paper), the manufacturers of paints, inks, varnishes and lacquers, and the manufacture of pens, pencils, art and office supplies. These are emissions to the air unless there is a spill.
Diffuse sources, and industry sources included in diffuse emissions data
Other possible emitters of trichloroethylene are degreasing operations, commercial and household painting and paint, varnish and lacquer removal, and consumer products containing trichloroethylene. These are emissions to the air unless there is a spill.
Trichloroethylene does not occur naturally in the environment.
No mobile sources.
Aerosol paints, adhesive glues, lubricating and oils, automotive chemicals, paint and varnish removers and thinners, typewriter correction fluids.
Sources used in preparing this information
- Agency for Toxic Substances and Disease Registry (1998), Public Health Statement: Trichloroethylene (accessed, May, 1999)
- CalEPA Air Resources Board Toxic Air Contaminant Summary Trichloroethylene (accessed, May, 1999)
- ChemFinder WebServer Project (1995), Trichloroethylene (accessed, May, 1999)
- Environmental Defense Fund (1998), Trichloroethylene: The Chemical Scorecard: (accessed, May, 1999)
- Environmental Health Center, a division of the National Safety Council, Environment Writer – Chemical Backgrounders Trichloroethylene (C2HCl3) (July, 1997) (accessed, May, 1999)
- National Environment Protection Council (1998a), National Environment Protection Measure for the National Pollutant Inventory (accessed, May, 1999)
- New Jersey Department of Health, Right to Know Program (1986), TRIFacts, Trichloroethylene (accessed, May, 1999)
- Technical Advisory Panel (1999), Final Report to the National Environment Protection Council.
- US Environmental Protection Agency and the Office of Air Quality Planning and Standards, (May 1998), Trichloroethylene (accessed, May, 1999)
- Safe Work Australia, Workplace exposure standards for airborne contaminants, accessed March 2019.
- National Health and Medical Research Council (NHMRC), Australian Drinking Water Guidelines (2011) - Updated October 2017, accessed May 2018.