After many years of being listed as a possible or probable human carcinogen, the widely used—and widely released to the environment—solvent trichloroethylene (TCE) has now been listed by the National Toxicology Program (NTP) of the U.S. Department of Health and Human Services as a “known human carcinogen.” See NTP’s 14th Report on Carcinogens (November 3, 2016).

TCE is an industrial solvent. Its principal uses are as a raw material in hydrofluorocarbon chemical manufacturing, and as a metal degreaser. In light of a number of human studies showing a causal connection between TCE exposure and an increased risk of kidney cancer, NTP reevaluated and ultimately reclassified TCE. In addition to cancer risk, other harms that have been attributed to TCE exposure include immunotoxicity, neurotoxicity, reproductive toxicity and developmental toxicity, such as potential fetal cardiac defects.

Exposure to TCE has been associated with its use in commercial (including dry cleaning) and industrial operations, and with its historical release to the environment. Reportedly, TCE has been found at over 1,000 of the approximately 1,700 current and former federal Superfund sites. It will be interesting to see whether this reclassification will give rise to any increase in toxic tort litigation relating to TCE exposure.