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Persistent Pollutants

US EPA turns down requests for more PFAS toxicity testing

Agency grants advocates’ petition but won’t require Chemours to study additional fluorochemicals

by Cheryl Hogue
December 30, 2021


The US Environmental Protection Agency (EPA) has deferred or turned down advocacy groups’ requests to require Chemours to conduct toxicity tests on dozens of fluorochemicals found in North Carolina drinking water supplies. The agency has already required or will require testing of 9 of the 54 compounds.

Per- and polyfluoroalkyl substances (PFAS), traced to a Chemours plant outside of Fayetteville, taint the Cape Fear River and wells that supply water for hundreds of thousands of people. Several of these compounds have been found in the blood of people who drank that water. But the health effects of this exposure remain unclear due to lack of toxicity data for the substances.

The EPA announced Dec. 28 that it was granting a petition from six North Carolina advocacy groups that sought testing of 54 fluorochemicals associated with Chemours’s Fayetteville operation. But the actions the agency indicated it will take in response fail to go beyond the EPA’s October 2021 strategy for testing PFAS, say petitioners from the Center for Environmental Health, Cape Fear River Watch, Clean Cape Fear, Democracy Green, North Carolina Black Alliance, and Toxic Free NC.

Chemicals with at least two adjacent carbon atoms, where one carbon is fully fluorinated and the other is at least partially fluorinated.
Per- and polyfluoroalkyl substances included in the National PFAS Testing Strategy developed by the US Environmental Protection Agency

“EPA is putting the financial interests of industry ahead of protection of devastated front-line communities,” Robert Sussman, the attorney representing the groups, says in a statement. “It is tragic that EPA is failing to use the authority it has to ensure that manufacturers pay for essential testing.”

The agency will require Chemours to test 5 of the substances listed in the petition, in line with its previously announced strategy.

The EPA will extrapolate results from studies on chemically-related PFAS for 23 of the compounds, the agency says in its response to the petition. The advocacy groups fault the EPA for not requiring studies directly on the 23 substances, which they say threaten human health.

Data for 9 more chemicals in the petition may be generated through future testing requirements, the EPA adds.

Chemical structure of difluorosulfoacetic acid.

The agency says that 15 chemicals in the petition don’t meet the definition of PFAS used for the EPA testing strategy: “chemicals with at least two adjacent carbon atoms, where one carbon is fully fluorinated and the other is at least partially fluorinated.” Fluorochemicals in the petition that do not meet this definition of PFAS include difluorosulfoacetic acid and perfluoro-3,5,7-trioxaoctanoic acid, the EPA says.

Chemours is testing 2 of these 15 fluorochemicals under a consent order, the agency notes. For another 4 of the 15, “relatively robust” data on toxicity are available, the EPA adds.

Emily Donovan of Clean Cape Fear calls the agency’s response disappointing.

“We deserve access to every health study our petition requested and the EPA has the legal authority to require Chemours pay for them,” she says in the same statement as Sussman.

In an emailed statement, Chemours says, “The EPA’s National PFAS Testing Strategy and participation of all manufacturers is important to a complete, holistic evaluation of PFAS compounds.”


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