Trichloroethylene poses health risks, US EPA confirms

Dozens of uses of trichloroethylene (TCE) pose unreasonable health risks to workers and consumers, the US Environmental Protection Agency concludes in a final assessment released Nov. 23. The assessment comes nearly 4 years after the EPA proposed, but never finalized, a ban on TCE in aerosol degreasers and dry-cleaning agents.

TCE is carcinogenic and associated with adverse neurological, developmental, and immunological effects. The EPA evaluated 54 uses of the chemical, including manufacturing, processing, and several commercial and consumer uses. The chemical is used primarily as an intermediate to manufacture refrigerants and as a degreasing solvent, according to the EPA. It is also found in adhesives and sealants, greases, paints, and cleaning products.

The EPA found unreasonable health risks for all but two of the 54 uses of TCE that it evaluated. The two uses that the agency says do not pose a risk are distribution of TCE and consumer use in pepper spray. The EPA has 2 years to finalize a rule to reduce the risks posed by the other 52 uses.

Environmental groups claim that the EPA’s assessment underestimates the risks of TCE because it does not use the most sensitive health effect—fetal heart malformations. Instead the agency relies on immunological effects of TCE. That approach “deviates from scientific best practices, defies requirements under the law, ignores longstanding agency policy, and is as much as 500-fold less protective of public health,” senior scientist Jennifer McPartland and lead senior scientist Richard Denison at the Environmental Defense Fund write in a blog post. The groups fear that future rulemaking by the EPA will be inadequate to address the true risks of TCE.

Environmental advocates are also concerned that the EPA did not consider the effects of TCE exposure from air, contaminated waste sites, groundwater used for drinking water, and food. The agency claims that such risks to the general population are addressed by other statutes, such as the Clean Air Act or Clean Water Act.

TCE is one of the first 10 chemicals the EPA is evaluating under 2016 revisions to the Toxic Substances Control Act (TSCA). The Trump administration delayed finalizing the TCE bans proposed in 2016 in favor of reevaluating more uses of TCE under the amended TSCA.