Trichloroethylene (TCE) is a human-made chemical that does not occur naturally in the environment. It does not easily break down or degrade in soils and groundwater, and can stay in the environment for a long time.
TCE is a pale blue, nonflammable liquid that evaporates easily and has a sweet smell, and has commonly been used as a metal degreaser. In homes, TCE may be found in paint, spot removers, carpet-cleaning fluids, metal cleaners, and varnishes.
Most TCE in air comes from metal degreasing activities associated with tool and automobile production. TCE can also enter groundwater and surface water from industrial discharges or from improper disposal.
Workers in degreasing operations have the highest risk of exposure to TCE. People who live near factories that use TCE may also be exposed to low TCE levels in the air. In homes, people who use TCE as a solvent (such as paint remover) can have exposure. TCE can be absorbed through the skin. Therefore, people who use the compound without solvent-resistant gloves may be exposed.
To learn how workers can be protected from harmful TCE exposures, view or download our TCE in the Workplace Fact Sheet, P-03201, also available in Spanish and Hmong.
TCE can enter groundwater and surface water from industrial discharges or from improper disposal of industrial wastes at landfills. Therefore, people who drink water from wells located near TCE disposal sites may be exposed. People can also breathe in vapors of TCE while showering as it evaporates from the water into the air.
The Department of Natural Resources (DNR) has set a residential indoor air action level for TCE at 0.39 parts per billion by volume (ppbV). The action level is considered to be protective of public health. If TCE concentrations in air are above the action level, we recommend that you take action to halt exposure even if the levels are not high enough to cause immediate harm.
If TCE-containing products are being used around you, you may be able to smell the chemical. If you can smell the chemical, the level is too high to be safe for exposure over long periods of time. Therefore, TCE-containing products should either be used briefly in small amounts, or should be used in well-ventilated areas.
The state and federal drinking water standards for TCE are both set at 5 micrograms per liter (µg/L).
The Department of Health Services (DHS) reviewed Wisconsin's groundwater standard for TCE in 2019 as part of the tenth cycle of groundwater standards. DHS recommends a groundwater standard of 0.5 µg/L based on updated scientific information. DHS recommends that people take action to reduce exposure when the TCE level in drinking water are equal to or greater than 0.5 µg/L.
Everyone's Reaction is Different
A person's reaction to chemicals depends on several things, including individual health, heredity, previous exposure to chemicals including medicines, and personal habits such as smoking or drinking. It’s also important to consider the length of exposure to the chemical, the amount of chemical exposure, and whether the chemical was inhaled, touched, or eaten.
Short-term exposure to high concentration
The following health effects may occur immediately or shortly after inhaling air that contains very high levels of TCE (more than 50,000 ppbV). Exposures of this degree would usually only be found in occupational settings.
- Heart problems including cardiac arrhythmias
- Nausea and vomiting
- Serious liver injury
- Dizziness, headache, neurological problems
- Eye, nose and throat irritation
The following health effects can occur after several years of exposure to TCE:
- In lab animals, inhaling TCE vapors or drinking TCE-contaminated water can cause effects in kidney, liver, lung and the immune system.
- There is growing evidence in studies of animals and people who handle pure TCE (very high levels) of increased rates of cancers of the kidney, liver, and non-Hodgkins lymphoma. The U.S. Environmental Protection Agency (EPA) characterizes TCE as “carcinogenic to humans” by all routes of exposure.
- Animal studies indicate there may be an association between maternal exposure to TCE and specific heart defects in the offspring. There is some evidence that human exposure to TCE while pregnant may be associated with similar effects. Pregnant women should avoid exposure to TCE.
There are tests to detect TCE in the breath, urine, and blood of people exposed to high levels of the compound within the previous 24 hours. TCE cannot be measured in people when it results from long-term, low-level exposure. Those suspecting TCE exposure over a long period of time should contact their physician. Blood chemistry analyses, which include liver and kidney function tests, may be helpful. Seek medical advice if you have any symptoms you think may be related to chemical exposure.