EPA Releases Long-Awaited Final Health Assessment for PCE

On January 10, 2012, EPA posted the long-awaited final health assessment for tetrachoroethylene - also know as perchloroethylene (PCE) - to EPA's Integrated Risk Information System (IRIS) database. PCE is a common chemical solvent and ubiquitous groundwater contaminant. The final health assessment concludes that PCE is a "likely human carcinogen". The document also provides toxicity values that will be used in revising the Maximum Contaminant Level (MCL) for drinking water, establishing new cleanup levels at sites where PCE is a contaminant, and evaluating whether to propose additional limits on the emission of PCE in the atmosphere.

EPA Extends Comment Period on Plan for Stricter PCE and TCE Drinking Water Limits

The Safe Drinking Water Act requires EPA to conduct a periodic review of existing National Primary Drinking Water Regulations and to determine which, if any, need to be revised. The purpose of the review, known as the Six-Year Review, is to identify those and limits requiring revision to improve or strengthen public health protection. EPA published its detailed review on March 29 2010 (75 FR 15500, March 29, 2010) and believes that four compounds are candidates for regulatory revision including acrylamide, epichlorohydrin, and the ubiquitous groundwater contaminants tetrachloroethene (PCE), and trichloroethene (TCE). The review suggest that stricter limits may be required for the compounds. Lowering of the MCLs for PCE and TCE would not only affect public drinking water supplies, but would require significant changes in groundwater monitoring programs and, in some cases, would push monitoring programs into corrective measures. EPA established a 60 day comment period for the March publication. This most recent extension, announced in a June 1 Federal Register notice, provides an additional 30 days (until July 1, 2010) to provide comments.