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PFAS "slip slidin" away down the regulatory superhighway

Steven Siros


  • Explains how PFAS generally break down slowly in the environment and are therefore ubiquitous in the environment.
  • Discusses the EPA’s revised health advisories in June 2022 for PFOS and PFAs.
  • Addresses the implementation of PFAS drinking water regulation and guidance at the state level.
PFAS "slip slidin" away down the regulatory superhighway
Aaron McCoy via Getty Images

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Unless you are living under a rock, you have undoubtedly heard references to per- and polyfluoroalkyl substances (PFAS), a class of emerging contaminants that are in the fast lane of the regulatory superhighway at both the state and federal levels. PFAS are a large, complex group of manufactured chemicals with unique nonstick, stain-resistant, and firefighting properties that have been used in many products over the past 70-plus years. Due to the unique characteristics of PFAS that allow it to instantly put out a jet fuel fire, prevent grease from leaking through a pizza box, or allow one to easily flip pancakes on a griddle, PFAS generally break down slowly in the environment and are therefore ubiquitous in the environment; they have been found in the blood of polar bears in the Barents Sea.

Although there are thousands of different PFAS compounds, our understanding of the potential impacts to human health and the environment is limited. And we don’t even know how to look for these compounds in the environment—at this stage, U.S. Environmental Protection Agency (EPA)-approved sampling methodologies allow us to identify only about 40 different PFAS and only in specific matrixes. Despite the limited scope of knowledge regarding the impact of PFAS on human health and the environment, regulators are moving at a very rapid pace to regulate PFAS (both on an individual and class basis). One of President Biden’s campaign pledges was to push for PFAS regulation, and in October 2021, EPA released its PFAS Strategic Roadmap that outlined the agency’s three-year strategy for addressing PFAS. Two key elements of EPA’s strategic roadmap were a promise to 1. promulgate drinking water standards for selected PFAS, and 2. regulate PFAS under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Resource Conservation and Recovery Act (RCRA). Each of these elements is briefly discussed below.

PFAS drinking water standards

In 2016, EPA established health advisories of 70 parts per trillion (ppt) for two of the more widely known PFAS—perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). Importantly, health advisories are not drinking water limits but rather levels that EPA has identified as having no adverse health or aesthetic effects. The 70 ppt health advisory level for PFOA and PFOS had been in place for five years, and EPA was under increasing pressure to revisit these levels. Then, in June 2022, EPA issued revised health advisories for PFOA and PFOS. The updated health advisory levels, which EPA claims are based on new science and consider lifetime exposure, were set at 0.02 ppt for PFOS and 0.004 ppt for PFOA. EPA also set final advisories for hexafluoropropylene oxide dimer acid and its ammonium salts (also referred to as GenX) at 10 ppt, and perfluorobutane sulfonic acid (PFBS) at 2,000 ppt.

Interestingly, the PFOA and PFOS health advisories are more than three orders of magnitude below the analytical detection limits for these compounds. Challenges have already been filed to the GenX health advisory level of 10 ppt, claiming that the health advisory is “arbitrary and capricious, and otherwise inconsistent with the law, because [U.S.] EPA incorporated toxicity assumptions that dramatically deviate from its own standard methods[.]” For example, challengers claim that U.S. EPA relied on significantly inflated “uncertainty factors” to ratchet down its reference dose that deviated from its own guidance and practice. Challengers also argue that EPA’s use of its Safe Drinking Water Act authority to issue health advisories violates several \constitutional requirements, including the non-delegation doctrine.

EPA also is the process of promulgating an enforceable drinking water standard or maximum contaminant limit (MCL) for specific PFAS compounds. These recently issued health advisories portend extremely low MCLs (likely approaching zero). However, new MCLs are unlikely until the latter part of 2023 at the earliest although EPA did submit its proposed rule to the White House Office of Management and Budget (OMB) on October 6, 2022.


On August 16, 2022, EPA published its proposed rule seeking to designate both PFOS and PFOA as “hazardous substances” under CERCLA. The OMB had previously completed its review of the proposed rule. Although OMB designated the proposed rule as “economically significant,” thus requiring a regulatory impact analysis, that designation is not expected to significantly slow EPA’s rulemaking.

Once EPA issues a final rule designating PFOA and PFOS as CERCLA hazardous substances, that action is likely to significantly expand the number of sites eligible for listing on the National Priorities List. In a letter submitted by the U.S. Chamber of Commerce to OMB, the Chamber estimated that the compliance costs associated with designating PFOA and PFOS as CERCLA hazardous substances could be as high as $22 billion.

Any action by EPA to designate PFOA and PFOS as CERCLA hazardous substances may also be foreshadowing a similar effort to designate these and other PFAS as “hazardous waste” under RCRA, which would subject these compounds to RCRA’s cradle-to-grave regulatory scheme.

State actions

Despite the regulatory initiatives discussed above, EPA remains in the slow lane as compared to the states. For example, as of August 2022, more than half of the states had implemented some form of PFAS drinking water regulation or guidance, and at least 12 states had implemented enforceable PFAS drinking water limits. The number of states with enforceable drinking water standards will likely continue to grow.

States are also increasingly regulating PFAS in a variety of products. For example, California has banned the sale of children’s products with PFAS beginning in July 2023 and cosmetics containing PFAS beginning in January 2025. Maine has banned the intentional use of PFAS in any products beginning in January 2030. Numerous states have also banned the use of PFAS in firefighting foam. In addition to already promulgated regulations, dozens of states are also contemplating product-specific bans of PFAS in, among other things, carpets, rugs, textile, and other stain- and water-resistant products.

PFAS will continue to face significant regulatory pressure at both the federal and state levels. At some point, EPA will probably catch up to the states, and the existing patchwork of PFAS regulations will likely be replaced by a more uniform set of federal regulations. What is certain, however, is that we will continue “slip slidin’” away down the PFAS regulatory superhighway.