An Environmental Protection Agency scientific panel is suggesting that a chemical used to make fluoropolymers poses a greater cancer risk than previously thought, a conclusion that an environmental group said could lead to a tougher regulatory approach.
In a widely anticipated report, EPA’s Science Advisory Board said perfluorooctanoic acid is a "likely” human carcinogen, a conclusion that is at odds with an earlier EPA staff review that only found much weaker, "suggestive” evidence that PFOA causes cancer.
While the June 27 report is not final, if the tough language remains, it could force EPA to conduct detailed cancer reviews – the first step toward banning or severely restricting PFOA, said Richard Wiles, senior vice president of Environmental Working Group in Washington.
SAB is a panel of outside experts hired by EPA to review its science. Similar boards for other chemicals generally have been influential in setting EPA policy. SAB said the EPA staff review, which had been praised by industry when it was released in January, did not give enough weight to evidence of cancer risks from PFOA.
"In considering the collective evidence, the majority of panel members concluded that the experimental weight of evidence with respect to carcinogenicity of PFOA was stronger than proposed in the [EPA staff] draft document, and suggested that PFOA is a `likely’ carcinogen in humans,” SAB said.
DuPont Co., which uses PFOA to make its Teflon fluoropolymer and has been heavily involved in the EPA proceedings, said its reading of the "weight of evidence” indicates PFOA does not cause cancer in humans.
"To date, no health effects are known to be caused by PFOA, even in workers who have significantly higher exposure levels than the general population,” DuPont said. The company said worker health data should get the highest consideration from EPA, because employees have the most exposure.
SAB still needs to finish the draft report, and then EPA must revise its earlier staff-level review based on the SAB report.
EWG’s Wiles predicted that the "likely carcinogen” label will remain, and he said that would put pressure on industry to find substitutes for PFOA, which also is found in chemicals such as coatings and firefighting foams.
PFOA and related perfluorinated chemicals have attracted a lot of attention from EPA because they mysteriously are found in the blood of most Americans at low levels, and they remain in the environment for long periods of time.
"We need to move away from these types of chemicals that stick around forever and can cause [several] types of cancer,” Wiles said.
EWG also suggested that the SAB review might increase pressure on EPA to levy a heavy fine against DuPont over EPA allegations that the company withheld studies showing health risks. The company and the agency have reached a tentative settlement, but have not settled on a fine publicly. The fine could range from about $10 million to more than $300 million.