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US Environmental Protection Agency| US Environmental Protection Agency

US Environmental Protection Agency| US Environmental Protection Agency

The Environmental Protection Agency’s (EPA) department is responsible for protecting the public against toxic substances. They have a new definition for PFAS forever chemicals, which excludes some of their widely-used compounds.

The Office of Pollution Prevention and Toxics created a new working term that is not only inconsistent with the scientific world but is also more narrow than those used by other EPA agencies.

Among other uses the narrower definition excludes chemicals PharmaceuticalsPFAS is a general term that covers pesticides and insecticides. The EPA also cited this narrower definition when it declined to act on some PFAS contamination discovered in North Carolina in December.

Per- and polyfluoroalkyl compounds, also known as PFAS, are a group of around 12,000 compounds that are used to make products waterproof, stain-, and grease-resistant. They are found in thousands products across many industries. They have been linked to cancer and birth defects, decreased immunity, kidney disease, and a variety of other serious health issues. Because of their long-lasting nature, they are often called “forever chemicals”.

The EPA is facing increased pressure to restrict all chemical classes. Critics say that the change benefits chemical producers, the Department of Defense, and industry.

There is a big difference in the definitions that industry uses and the international scientific communities use. Linda Birnbaum (ex-EPA scientist and head, National Toxicology Program) said, “There is a real distinction in the definitions that industry uses and the international scientific community uses.”

An EPA official spoke to the Guardian under anonymity and said that the new definition was completed about a calendar year ago. Discussions are ongoing over its implementation.

This issue is now being investigated by the EPA’s new chemicals division managers. They are facing whistleblower charges alleging that management altered risk assessments to make PFAS seem less toxic.

Although the EPA did not immediately respond to questions, a Guardian document reveals that the new definition focuses only on PFAS considered to be the most concerning due to their persistence and potential for human exposure.

According to researchers, the debate over PFAS has been centered on chemical structure and is being fought by the international scientific community. Because they are fluorinated, PFAS cannot be completely broken down, they are known as forever chemicals.

The Organization for Economic Cooperation and Development (OECD) proposes the most inclusive and widely used definition. It defines any chemical that has one fluorinated carbon atom, as a PFAS. This could encompass tens or thousands of chemicals available on the marketplace.

However, the EPA toxics department created a working definition which requires at most two adjacent carbon atoms. One carbon must be fluorinated fully and one must be at minimum partially fluorinated. It covers around 6,500 PFAS. The EPA has used that definition in its recently released national testing strategy, which is a roadmap in its effort to curb PFAS pollution.

The definition does not include chemicals in pesticides or pharmaceuticals. However, it does exclude some refrigerants from the list as well as PFAS gases. As they are metabolized or broken down by the body, some of the PFAS compounds that are exempted can become highly toxic chemicals like PFOA, PFOS, and PFOA. Some of these PFAS compounds can be produced by using other more dangerous PFAS chemicals.

Birnbaum explained that it is difficult to say something isnt PFAS when it is metabolized or is exposed to changes in the environment.

Partly, the definition debate revolves around chemicals persistence. Most chemicals with a fluorinated carbon atom won’t fully break down. However, some compounds are. accumulatingThere are alarming levels all over the planet, said Ian Cousins (a Stockholm University PFAS researcher) who co-authored papers.

While the levels are rising, toxicity is still low. So should we be worried? He asked. I said yes because we shouldn’t release substances that increase in our environment and eventually we might discover a problem when it is too late.

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Photo: Noor-A-Alam

Cousins, along with other experts, believe that there should be a discussion on how to narrow the definition. However, the toxic office approach is too restrictive. The EPA’s Office of Research and Development seems to have reached a compromise and is using a definition that includes approximately 12,000 PFAS chemicals. Deborah Ross, a US congresswoman, introduced legislation to create one fluorinated-carbon atom.

The Guardian spoke to an EPA official who said they were not involved in the discussion that preceded this definition change. However, he said that chemists from the agency’s new chemicals division likely developed it. According to the employee, the chemical structure of the compound was what the chemists used to define the compound and not their potential dangers to human health or the environment.

The employee stated that the exclusions of certain PFAS compounds were a problem but that it was difficult to come up with a suitable definition.

The changes in definitions have already been observed in North Carolina’s Cape Fear basin, which has suffered decades of pollution from a PFAS-manufacturing plant owned by Chemours. A citizen group petition in 2019 asked the EPA for studies to reveal the health effects of 54 PFAS compounds found within human blood and water.

The agency’s December 2021 response stated that it would not test for 15 chemicals that it claimed did not meet the toxics office definition of PFAS. The citizen groups are suing, and Chemours and the Justice Department are coordinating with Chemours in defense of them, said Bob Sussman. Sussman is an environmental attorney for these groups.

In its response, the EPA stated that some of the chemicals excluded are likely to degrade in nature and others will become TFA. This was a well-studied substance. Researchers say that most substances, such as TFA, don’t fully break down and that studies show it is accumulating within the environment. ToxicLong-term exposure.

Critics also pointed out that there was not enough data to determine the toxicity of certain chemicals and that PFAS have been allowed to be used without toxicological data. Kyla Bennett, a former scientist at EPA, stated that GenX, PFOA, and PFOS are three of the most toxic compounds.

She said that the biggest problem is that the EPA doesn’t know everything. I would prefer to use the precautionary principle, and capture chemicals that may not deserve to be regulated as severely as miss [dangerous chemicals].

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