Tetrachloroethylene Final Risk Assessment

EPA has posted the final health assessment for tetrachloroethylene – also known as perchloroethylene, or perc – to EPA’s Integrated Risk Information System (IRIS) database. Perc is a chemical solvent widely used in the dry cleaning industry. It is also used in the cleaning of metal machinery and to manufacture some consumer products and other chemicals. The assessment provides estimates for both cancer and non-cancer effects associated with exposure to perc over a lifetime. The Toxicological review provides information on uses and occurrence, toxicokinetics, hazard characterization, and dose-response assessment. It covers both ingestion and inhalation risk and cites health impacts due to neurotoxicity as well as cancer. The oral reference dose (RfD) for noncancer effects is established as 6 x 10-3 mg/kg-day. This RfD is equivalent to a drinking water concentration of 0.21 mg/L, assuming a body weight of 70 kg and a daily water consumption of 2 L. The final assessment characterizes perc as “likely to be carcinogenic to humans.” The toxicity values reported in the perc IRIS assessment will be considered in revising EPA’s Maximum Contaminant Level for perc. This updated risk assessment will support the current evaluation of perc under the carcinogenic volatile organic compounds group in drinking water, part of the agency’s drinking water strategy.

For more information on the perc IRIS assessment go to http://www.epa.gov/iris/subst/0106.htm. For more information on perc go to http://epa.gov/oppt/existingchemicals/pubs/perchloroethylene_fact_sheet.html.