New EPA PFAS framework expects most PFAS to be PBTs

PFAS, PBTs, and EPA regulation

• Per- and polyfluoroalkyl substances (PFAS) are a wide class of synthetic organic chemicals that are used across industrial and commercial products in a variety of diverse applications. PFAS are prized for their ability to withstand heat and other environmental stressors, leading to molecules that can easily persist in ambient environments. PFAS also repel both water and oil, which makes them ideal for many applications in textiles and coatings.
• Although there is no single definition utilized for PFAS, the general “hallmark” of a PFAS is a chain of fully fluorinated carbon atoms. These carbon-fluorine bonds are extremely strong, leading to the chemicals’ ability to resist environmental stressors. Certain PFAS have been linked to adverse health outcomes, including effects on the metabolism, fertility, and reduced fetal growth.
• Persistent, bioaccumulative, and toxic (PBT) chemicals are a group of chemicals targeted for additional regulation by the Environmental Protection Agency (EPA). PBTs persist and bioaccumulate within the environment, leading to increased exposures to humans and the environment over time. These exposures may lead to effects not necessarily identified or properly accounted for within normal hazard or risk assessment methodologies.
• Under the Toxic Substances Control Act (TSCA), the EPA is tasked with regulating chemicals currently in commerce as well as new chemicals that have not yet entered the market. Under the agency’s New Chemicals Program, the EPA must make an affirmative determination of whether a chemical represents an unreasonable risk to human health or the environment under known, intended, or reasonably foreseen conditions of use.
• The agency may require additional risk management or mitigation for new chemicals or new uses of chemicals under TSCA section 5. Section 5(e) actions are generally consent orders between the EPA and a private organization, where the agency may determine that it does not have the information available to make a reasoned evaluation of the health and environmental effects of the new chemical substance or the significant new use, which may lead the EPA to find that the chemical may present an unreasonable risk to human health or the environment. These orders may include a number of risk mitigation steps for the company, including additional environmental or toxicokinetic testing, personal protective equipment (PPE) requirements for occupational handlers of the substance, distribution and use restrictions, or restrictions on releases of the product.
• The EPA may also limit the manufacture, import, or distribution of chemicals under TSCA section 5(f). These section 5(f) orders come after the agency determines that a new chemical or significant new use of an existing chemical may pose an unreasonable risk to human health or the environment and allow the EPA to limit the amount of a substance manufactured or imported into the U.S., or fully prohibit the manufacture (including import), processing, and distribution of the chemical.

New framework for TSCA new chemicals review of PFAS

• On June 29, 2023, the EPA released the Framework for TSCA New Chemicals Review of PFAS Premanufacture Notices (PMNs) and Significant New Use Notices (SNUNs). The new framework is part of a greater PFAS strategy from the agency detailed in the agency’s strategic roadmap for PFAS. The document targets new PFAS or significant new uses of existing PFAS and details the agency’s plan for reviewing these substances in the future.
• The framework uses a newer definition of PFAS utilized by the agency in 2023. The EPA considers PFAS to include substance with alkyl or alkyl ether structures where all saturated carbons are fully fluorinated (e.g., that all hydrogen atoms have been replaced with fluorine atoms) with a mixture of fully fluorinated, partially fluorinated, or non-fluorinated saturated carbons. The agency defines “PFAS” in the framework as a chemical substance that contains one of the following three structures: (1) “R–(CF2)–CF(R′)R′′, where both the CF2 and CF moieties are saturated carbons”; (2) “R–CF2OCF2–R′, where R and R′ can either be F, O, or saturated carbons”; or (3) “CF3C(CF3)R′R′′, where R′ and R′′ can either be F or saturated carbons.” This definition has been utilized by the EPA since January 2023, when it proposed adding Significant New Use Rules (SNURs) for PFAS on the TSCA that have been inactive since 2006.
• The agency considers potential metabolites or degradants of PFAS to also be within the definition of “PFAS” for the purposes of the framework. The agency explained that it has reviewed natural processes that can break down PFAS into degradants or metabolites that are potentially more stable and deleterious to human health or the environment, and that certain PFAS can break down into stable and bioaccumulative end products. The agency will focus on any of these potential metabolites or degradants when reviewing a chemical for TSCA section 5 purposes.

Agency processes for reviewing available information

• Once the agency confirms that the substance under review meets the framework’s definition of a PFAS, it will begin reviewing all available data on that specific PFAS. The PMN or SNUN provided in the submittal must include all information in possession or control of the submitter, which can better inform the agency’s evaluation on potential human health or environmental risks. The agency will also use this time to determine whether the chemical is a PBT utilizing a weight-of-evidence approach for data from the new chemical itself or “appropriate analogues.” The agency will consider additional testing needs if there is no appropriate information to make a determination on.
• The agency expects that “most PFAS” will be considered PBTs. The agency will review both the chemical itself as well as metabolites or degradants when assessing environmental releases and worker exposures. The agency will only qualitatively, not quantitatively assess the potential extent of exposures to the general population. The framework explains that quantitatively assessing exposures may only provide a snapshot of an exposure at one time and may not accurately reflect the overall exposure and health risks of the chemicals due to persistence and bioaccumulation.
• If the PFAS is not considered a PBT, it will go through the traditional New Chemicals Program approach, where the agency will conduct a quantitative risk assessment when appropriate. The agency also noted that it would consider the full lifespan of a PFAS and potential opportunities for exposure.
• If the PFAS is consider a PBT, the EPA will review exposure pathways and receptors. The agency will quantitatively assess risk factors associated with PBTs that “represent limitations to the standard New Chemicals Program risk calculation methods,” including issues like background levels of PFAS and the persistence and bioaccumulation of many studied PFAS.
• The EPA expects to use its authority to issue testing under TSCA section 5(e) when submitted information does not meet the agency’s requirements to make a reasoned determination of health and environmental effects. The risk assessment may generate testing recommendations for the EPA risk managers to include as part of risk management rules for a chemical substance. These testing requirements may include information on physical chemical properties, environmental fate and effects, and human health effects.
• The agency expects to issue TSCA section 5(e) and 5(f) orders for many chemicals covered under the framework. The agency will issue section 5(e) orders if it finds that the chemical may present an unreasonable risk or if it does not have sufficient information to make that determination. The agency will also issue a section 5(e) order if the substance is produced in substantial quantities and there may be significant or substantial human or environmental exposure. If a substance presents an unreasonable risk, the agency must take action under section 5(f) (or an immediately effective rule under TSCA section 6(a)). The section 5(f) order would only apply to the submitter, but a rule under section 6(a) would apply to all manufacturers, importers, or users of the substance. However, if the substance is not likely to present an unreasonable risk, the EPA will notify the submitter of the decision and will publish a notice in the Federal Register announcing the decision.
• The EPA expects that it is “unlikely” that PBT PFAS receive a determination of “not likely to present an unreasonable risk.” Therefore, since most PFAS are expected to be PBTs and most PBT PFAS will receive determinations that they may present unreasonable risks, the agency will likely issue section 5(f) orders or 6(a) rules for the majority of PFAS reviewed under the framework.
• For PBT PFAS that have negligible exposure or environmental release scenarios (such as those in a closed-loop production process), the EPA will likely only require physical-chemical testing of the PFAS prior to manufacture. If the submitted data does not result in increased concerns about environmental releases, the agency will likely not require additional upfront testing.
• In a low exposure and environmental release scenario, the agency will likely require both physical-chemical and additional testing to be completed and submitted prior to manufacture. This may include toxicokinetic testing. The agency is also considering “orders that would impose additional protections if the new data demonstrate greater concern than EPA concluded based on the reasonably available data considered during review of the” chemical.
• In a scenario with expected exposure or environmental release, the EPA would impose the strictest testing requirements. The frameworks explains that the agency will likely require a “full suite” of testing before the substance can be manufactured. This would include physical-chemical testing in addition to a wide array of other testing including toxicokinetic, human health, and environmental toxicity testing. The agency would allow manufacture if there were sufficient limitations or prohibitions to sufficiently mitigate exposures and releases, or the agency may fully prohibit the manufacture “if warranted.”
• The agency may allow the use of a new PBT PFAS if the substance is needed by another federal agency or is “required in order to meet a critical need.” This language is included particularly for the semiconductor industry as the United States government attempts to onshore as much production in the U.S. if possible. Certain photo acid generators (PAGs) utilized in photolithography are PFAS but are essential for the complicated semiconductor manufacturing process. The agency has already developed an approach for reviewing other materials essential to the semiconductor industry and will likely acquiesce to requests for a PBT PFAS that is filling a “critical need” in semiconductor production.

What is the impact of the framework?

• The framework will almost certainly be extremely influential in future reviews of PFAS. The agency is heavily leaning on additional and more onerous regulation for PFAS, and the expectation that most PFAS will be PBTs and will have additional TSCA section 5(f) orders or 6(a) rules attached means that the chemicals will undergo significantly more regulation than in previous years.
• Despite its plans for PBT PFAS, the agency appears to be flexible with “critical uses” which it does not further define. This will likely mean that the agency will fast track chemicals that are required for defense or other “politically popular” industries that are receiving a significant amount of support from the government as we have seen in recent proposed risk management rules for methylene chloride and perchloroethylene.

To contact the author of this analysis, please email Walker Livingston.
To contact the editor of this analysis, please email Patricia Iscaro.

Key Documents and Dates

• Framework for TSCA New Chemicals Review of PFAS Premanufacture Notices (PMNs) and Significant New Use Notices (SNUNs)
• Toxic Substances Control Act (TSCA)