The Office of Pollution Prevention and Toxics (OPPT) at the U.S. Environmental Protection Agency (EPA) is no longer employing a “working definition” of PFAS (per- and polyfluoroalkyl substances) in its National PFAS Testing Strategy that excluded f-gases and trifluoroacetic acid (TFA), the atmospheric byproduct of certain f-gases.

In a May 23 email, the OPPT stated that it “is no longer using a ‘working definition’ to characterize the universe of PFAS subject to the office’s various PFAS testing, reporting and regulatory efforts. Moving forward, OPPT intends to continue to explain the rationale for identifying specific PFAS substances it believes are appropriate to include within the scope of each individual action.”

This email was shared by Tim Whitehouse, Executive Director, Public Employees for Environmental Responsibility (PEER), in a presentation on the PFAS panel at the ATMOsphere (ATMO) America 2023 conference, held in Washington, D.C., June 12–13. ATMO America was organized by ATMOsphere, publisher of R744.com.

The EPA’s working definition of PFAS took a narrow view that described the chemicals as containing at least two adjacent carbon atoms, where one carbon is fully fluorinated and the other is at least partially

fluorinated. However, a number of U.S. states, including Maine and California, as well as the EU, have adopted a broader definition of PFAS that includes f-gases and TFA. This definition, published in 2021 by the OECD (Organization for Economic Co-operation and Development) and endorsed by a wide range of scientists, defines PFAS as fluorinated substances that contain at least one fully fluorinated methyl or methylene carbon atom.

The OECD definition of PFAS not only includes f-gases but the TFA into which some f-gases, notably HFO-1234yf, decompose in the atmosphere. TFA comes down to Earth in rainwater and has been found to accumulate in water supplies and arctic ice, raising concerns about its ultimate health impact.

Last week, U.S. Senators Tom Carper (Democrat from Delaware) and Shelley Moore Capito (Republican from West Virginia) – Chair and Ranking Member, respectively, of the Senate Environment and Public Works (EPW) Committee – released draft PFAS legislation that includes the narrower PFAS definition previously employed by the EPA.

In the EU, the European Chemicals Agency (ECHA) In February published a proposal from the national authorities of Denmark, Germany, the Netherlands, Norway and Sweden to restrict PFAS under REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals), the EU’s chemicals regulation, following the broader OECD definition of PFAS. The “Universal Restriction Proposal” – officially known as the Annex XV Restriction Report – would restrict the manufacture, use or sale of certain f-gas refrigerants as substances on their own or in blends according to certain thresholds.

Why this definition?

In April 2022, in a suit against the EPA, PEER alleged that the agency was “withholding documents explaining why it has adopted an exceedingly limited definition of [PFAS].”

EPA subsequently released more than 2,500 pages of documents, but in June 2022 PEER said in a statement that it found “no scientific basis” for the EPA’s working definition of PFAS, and “no reasons given for excluding thousands of chemicals included in State definitions.” PEER added that it would challenge in court redactions in the EPA’s documents that “may mask the scientific basis” for its PFAS definition.

Though EPA has now dropped its working definition of PFAS, Whitehouse said at ATMOsphere America 2023 that its suit against the EPA is ongoing.

Peer has found different EPA offices define PFAS differently. “But PFAS doesn’t know different EPA offices (water, air, solid waste, etc.),” said Whitehouse at the conference. “Pollution doesn’t know political boundaries.”

“The EPA needs to come up with a solid definition of PFAS based upon science and consistent with definitions developed in Europe and elsewhere,” he said.

The absence of a standard PFAS definition at the EPA means that there will be “piecemeal legislation at the federal, state and local level and increased litigation and consumer pressures,” said Whitehouse, who added that “the piecemeal approach is an unworkable solution.”

Whitehouse criticized the EPA’s “deference to industry pressures” in all of its chemical programs, citing an email in which the EPA’s Office of Pesticides Programs announced a staff party to celebrate the “1000th study waived.”

The capacity of the government to conduct independent scientific research “is getting very degraded,” he added. “The EPA relies on industry for studies, and doesn’t have scientists to question industry very well.”

PEER’s suit against the EPA stemmed from the perception that EPA was not being transparent about how it came up with its PFAS definition. “When EPA puts out a definition it needs to rely on, it normally goes through public notice and comment and there’s some sort of scientific underpinning for those definitions,” said Whitehouse. “But here there wasn’t.”

The lawsuit seeks to determine the scientific and regulatory basis for the EPA’s definition. PEER has started to receive some documents from the EPA but “so far we haven’t gotten a good answer,” he said.

“So while Europe is trying to wrap its arms around this, and provide a definition and certain exceptions, things are getting less and less clear with the EPA in terms of what they mean by PFAS,” Whitehouse said.

The EPA did not respond to a request for comment for this article.

So while Europe is trying to wrap its arms around this, and provide a definition and certain exceptions, things are getting less and less clear with the EPA in terms of what they mean by PFAS.”

Tim Whitehouse, Executive Director, Public Employees for Environmental Responsibility