EPA is advised to increase estimate of PFOA's cancer risk

EPA's Science Advisory Board (SAB) is recommending that the agency deem perfluorooctanoic acid (PFOA) a "likely" human carcinogen. The scientific advisers endorsed a report at a Feb. 15 meeting that says the compound poses a greater risk than described in an EPA draft risk assessment of PFOA released in January 2005. That draft found only "suggestive evidence" that the compound poses a cancer risk (C&EN, Jan. 17, 2005, page 28). Before SAB approved the report, researchers from 3M, a former manufacturer of the substance, and DuPont, which has used PFOA for decades, argued against upgrading the classification of the chemical's cancer risk. They said the board's recommendation was largely based on a study linking PFOA to mammary gland tumors in rats. They cited an unpublished report reexamining that study and dismissing the cancer association. SAB members noted that much new information is emerging on the health effects of the chemical, and EPA will consider it as the agency crafts the final version of the PFOA risk assessment.