COVID-19 Info | Information sur la COVID-19 | COVID-19 Vaccine Vaccine Receipt | COVID-19 Self-Assessment
🔍 Search
  • Follow us:
Sign In FR

Middlesex-London Health Unit

Inner Nav

Trichloroethylene (TCE)

Trichloroethylene (TCE) is a man-made, colourless, non-flammable liquid at room temperature with a somewhat sweet odour. TCE is highly volatile, which means that it will evaporate quickly into the air where it is present in a liquid form. The two most common uses of TCE are as a de-greaser for metal parts and as a component in the manufacturing of other chemicals such as chlorinated hydrocarbons and polyvinyl chloride; however, it has also been used in consumer applications such as paint removers, adhesives, pesticides and spot removers.


Contact Us

To speak with a Public Health Inspector on the Environmental Health Team about Trichloroethylene (TCE), please call:

  • 519-663-5317

How does TCE get into the environment?

TCE is a man-made chemical that is not believed to be naturally present in the environment, and therefore tends to enter the environment at sites where it is produced, used or disposed of. The largest source of TCE in outdoor air is reported to be evaporation from factories that use it as a metal de-greaser.

TCE may also be present in water or soil if stored, disposed of or transported improperly. While it evaporates quickly, it can remain in soil and groundwater for months to years. 

Back to Top

How are people exposed to TCE?

The main routes of exposure to TCE in the community are through inhalation of TCE in indoor air and drinking water. TCE can enter indoor air through a process know as "soil vapour intrusion," where TCE evaporates from contaminated soil and/or groundwater, enter the air spaces between soil particles (i.e. soil vapour), and then migrates through building foundations into the building's indoor air. 

When TCE is present in groundwater, exposure may also occur through well water. The municipal drinking water supplied by the City of London is highly regulated, monitored regularly for over 100 chemicals, including TCE, and it is safe for consumption.

Back to Top

What health risks are associated with TCE exposure?

As with exposure to any chemical, potential health effects of TCE depend on how much a person was exposed to, how long a person was exposed and other factors associated with the individual (such as age, health, lifestyle choices, family traits, and other chemicals the person is exposed to).

Acute (short-term) health effects of TCE, such as lightheadedness, dizziness or lethargy, are unlikely to occur at the levels of TCE typically measured in indoor air concentration in homes. Some occupationally exposed individuals have developed rashes after coming into contact with concentrated TCE solutions.

Long-term exposure at sufficiently high concentrations of TCE can cause liver and kidney damage and affect immune system function. As well, TCE exposure of this nature has been associated with an increased risk of kidney cancer, liver cancer and non-Hodgkin’s lymphoma. There is also some evidence that TCE may be related to certain types of heart malformations in the developing fetus.

Back to Top

How can I limit my exposure to TCE?

Ventilating indoor air can be an effective way to reduce the amount of TCE present in your home. To inhibit vapour intrusion, the migration of TCE from soil to indoor air, the following measures can be taken:

  • repairing and/or sealing any cracks in the foundation of your home, and
  • checking that sump pumps and pumping traps are working properly.

If there are elevated concentrations of TCE in your indoor air; sub-slab depressurization and other methods such as soil vapour extraction are useful in preventing the movement of TCE from soil vapour into indoor air. To be sure that you achieve an effective solution, it is best to consult a building professional with expertise in indoor air quality.

If you are concerned about TCE in your well water, it is best to consult a water treatment professional who can assess your water supply and provide advice on solutions that would be practical in your setting (e.g. granular activated carbon (GAC) filters can be used, but need to be replaced regularly).

Back to Top


Date of creation: March 10, 2015
Last modified on: February 13, 2020


1Public Health Ontario. (n.d.). A public health approach to trichloroethylene in indoor air and drinking water. Toronto, ON: Queen’s Printer for Ontario.
2Public Health Ontario. (n.d.). Appendix B: Trichloroethylene (TCE) - Health unit fact sheet. Toronto, ON: Queen’s Printer for Ontario.