Trichloroethylene: A possible carcinogenic (cancer-causing) compound used mainly as a degreaser for metal parts. Trichloroethylene was also at one time used to decaffeinate coffee and as an anesthetic.
There are limited findings of elevated liver and biliary tract cancer rates in occupational groups exposed to trichloroethylene. There is also evidence of cancer formation in experimental animals exposed to trichloroethylene. The US government in 2000 classified tetrafluoroethylene as "reasonably anticipated to be a human carcinogen."