On Sept. 11, 2025, the Environmental Protection Agency (EPA) asked the D.C. Circuit Court of Appeals to vacate the agency’s own drinking water standards (MCLs) for four PFAS chemicals: PFNA, PFHxS, HFPO-DA, and (through a “hazard index”) PFBS (referred to collectively as the “Index PFAS”). EPA is now apparently siding with the group of petitioners that are challenging the PFAS National Primary Drinking Water Regulation, which was promulgated in 2024 during the Biden administration. EPA is now claiming that the portion of the rulemaking process that resulted in the MCLs for the Index PFAS was procedurally improper, and that, as a result, the standards are invalid. EPA is continuing to defend the challenges to the portion of the rule that sets MCLs for the two most prevalent PFAS, PFOA and PFOS.

The alleged defect in the process for setting MCLs for the Index PFAS was EPA’s decision to propose goals and standards for those chemicals concurrently with its preliminary determination that they should be regulated. EPA is now alleging that Section 1412 of the Safe Drinking Water Act (SDWA), 42 U.S.C. § 300g-1, requires EPA to propose to regulate a new contaminant – and consider comments on such a proposal – before it may publish even proposed drinking water standards.

EPA’s latest pronouncement against this portion of its own rule is not a complete surprise. In May of this year, EPA issued a press release “announcing its intent to rescind the regulations and reconsider the regulatory determinations for [the Index PFAS].” The press release did not, however, indicate that EPA would attempt to use the pending court challenges as the vehicle to eliminate the Index PFAS MCLs.

EPA’s latest position in the litigation does not necessarily mean the Circuit Court will vacate the Index PFAS MCLs. A number of entities, including the Natural Resources Defense Council (NRDC), had previously intervened in the consolidated challenges to the PFAS standards on behalf of EPA. The intervenors have supported the rule separately from EPA and, according to EPA’s brief, intend to respond to EPA’s change-of-position on this issue. Furthermore, following the Supreme Court’s decision last year in Loper Bright Enters. v. Raimondo, 603 U.S. 369, 412-13 (2024), EPA may no longer be entitled to Chevron deference for its interpretation of the SDWA and what is required and prohibited by Section 1412. Accordingly, it is not clear how much EPA’s new legal interpretation will affect the outcome of the litigation.

Further, a finding that the proper procedure was not followed would not automatically compel the court to vacate the rule. EPA’s brief acknowledges that when determining whether to vacate a rule, the court should consider both “the seriousness of the order’s deficiencies…and the disruptive consequences of an interim change that may itself be changed” (Allied-Signal, Inc. v. Nuclear Regulatory Commission, 988 F.2d 146, 150-51) (D.C. Cir. 1993).) Given that the MCLs do not need to be met until 2029, vacating them at this stage is unlikely to be found to be disruptive. But there may be questions about whether the sequencing of the EPA’s actions was seriously deficient.

If EPA is unable to have the Index PFAS MCLs vacated, it could pursue the same result through a rulemaking process. Accordingly, many are now arguing that it appears increasingly unlikely that drinking water providers will ever have to comply with the Index PFAS MCLs.

For further information regarding PFAS MCLs, contact a member of Taft’s Environmental group.

EPA’s stance on the 2024 PFAS Rule continues to remain in the balance. But as the clock continues to run on litigation over the Rule, EPA may be forced to provide a conclusion in the near future.

The Rule

On May 8, 2024, the U.S. Environmental Protection Agency (EPA) published a final rule designating two widely used per-and polyfluoroalkyl substances (PFAS) —perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS)—as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Notably, the Rule was the first time EPA used CERCLA section 102 to list hazardous substances by regulation. The Rule became effective July 8, 2024.

Challenges to the Rule

The U.S. Chamber of Commerce and various industry groups filed a petition on July 10, 2024, in the U.S. Court of Appeals for the District of Columbia Circuit challenging the Rule. Chamber of Commerce of the United States of America, et al v. EPA, et al., Case No. 24-1193 (D.C. Cir. 2024). In the most recent filing in the case through August 20, 2025, the U.S. Court of Appeals for the D.C. Circuit granted EPA’s fifth unopposed motion for a 30-day stay extension of the stay of the litigation. The request follows in a series of extensions already granted by the appellate court since the Trump administration began participating in early 2025, including on February 24, April 30, June 2, and July 11. The stated purpose of the continuing stay is to allow EPA leadership additional time to finalize its legal position on the Rule. Now, with a September 17 deadline to tell the U.S. Court of Appeals for the District of Columbia Circuit how it plans to proceed on industry’s challenge to the Rule, it appears that EPA will soon be forced to confirm its position.

Despite the ongoing Rule challenge, states and other entities have already cited the Rule in their filings of cost recovery claims under CERCLA’s section 106 in efforts to recoup costs from potentially liable parties for PFAS cleanups.

Possible Outcomes

Considering that EPA has,  for several months, been punting on whether to uphold the 2024 rule, it could be a signal that the Agency is steering toward reversing its planned support for the Rule. In this regard, the New York Times reported that Steven Cook, principal deputy assistant administrator in the Office of Land and Emergency Management (OLEM),  recently met with industry parties challenging the Rule and, the following business day, OLEM revised a recommendation on the Rule to suggest repealing it, rather than supporting it.

In contrast to these recent signals, EPA Administrator Lee Zeldin suggested support for the Rule as recently as April 28, 2025, when he announced support for maintaining the “polluter pays” model with respect to PFAS, while noting plans for targeted liability carveouts for so-called “passive receivers.”

Nevertheless, the issue remains the subject of litigation, and as indicated in documents filed with the court, no decisions have been made, and Administrator Zeldin has yet to publicly confirm his decision on the future of the Rule.

Taft attorneys have been at the forefront of PFAS litigation for more than two decades and have worked on issues involving these chemicals from before they were regulated to their current status as a focal point of state and federal environmental regulation. For help navigating PFAS laws, contact Taft attorneys Frank Deveau, Will Gardner, and Tommy Sokolowski.

In 2023, Minnesota enacted Amara’s Law (Minn. Stat. § 116.943), requiring certain reporting and implementing prohibitions of intentionally-added PFAS in certain products. The law requires manufacturers of intentionally-added PFAS-containing products to report specified information to the Minnesota Pollution Control Agency (MPCA) by January 1, 2026. These reports must include the type of PFAS added to the product and its purpose in the product. In June, the MPCA stated its intent to extend the reporting deadline, but did not specify a date.

On July 23, the MPCA announced that the reporting deadline would be extended from January 1, 2026 to July 1, 2026. This provides an additional six months for manufacturers to submit their initial reports of products sold in Minnesota that contain intentionally-added PFAS. This extension means that manufacturers will have three years between when the law was enacted and the reporting date. The MPCA stated that the extension was justified to allow manufacturers more time to “establish agreements with suppliers to report on their behalf” and to “become familiar with a new reporting platform.” The agency also stated that its decision was made in light of ongoing engagement with stakeholders.

This reporting deadline extension comes on the heels of the 2025 Minnesota Legislature expanding the list product categories that are exempt from the provisions of Amara’s Law (Minn. Sess. Laws 1Sp2025 ch. 1, art. 4, s. 19 and 20). The list of exemptions has been expanded to include products that contain intentionally-added PFAS solely in electronic components or internal components and in several types of children’s vehicles.

Note: this post contains links to articles written in Italian.

On June 26, the Court of Assizes of Vicenza issued a criminal judgment convicting 11 chemical plant executives for environmental crimes related to PFAS contamination. Pollutants from the Miteni chemical plant are alleged to have spread across more than 70 square miles in northern Italy’s Veneto region, impacting soil, groundwater, and drinking water for an estimated 350,000 people. The historic ruling marks the first time a court has held corporate managers criminally liable for PFAS pollution.

PFAS exposure from Miteni chemical plant

Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals known for their resistance to water, grease, heat, and corrosion. These “forever chemicals” widely found in consumer products are extremely persistent in the environment and the human body. As testing for PFAS expands globally, studies have revealed that a vast majority of people now carry these chemicals in their blood.

In 2013, after scientists detected high levels of PFAS in water bodies near the Miteni chemical plant, the Veneto government began blood testing residents of surrounding provinces. The region declared a state of emergency due to PFAS contamination in 2018. In 2020, a “Red Area” of maximum exposure covered approximately 230 square miles including 30 municipalities and approximately 140,000 people. One study of residents in the Red Area found higher relative risk for general mortality, diabetes, cerebrovascular diseases, and some forms of cancer. Another study found evidence of increased mortality from cardiovascular disease, and kidney and testicular cancer.

Corporate transitions and executive accountability

While ownership of the Miteni facility had shifted over time, the court found that corporate transactions did not absolve individual responsibility for the alleged pollution of one of Europe’s largest groundwater basins and resulting environmental disaster. Founded in 1965, the chemical plant operated as a subsidiary of Mitsubishi from the 1980s until the plant was sold to International Chemical Investors Group (ICIG) in 2009 for the price of one euro. The plant closed due to bankruptcy in 2018.

Former leaders from Miteni, Mitsubishi Corporation, and ICIG were sentenced to prison terms ranging from 2 years and 8 months to 17½ years. Notably, the court imposed harsher sentences than prosecutors had requested, totaling more than 141 years across the 11 convictions. Civil damages totaled over €75 million (approximately $80 million USD), including over €56 million awarded to Italy’s Ministry of the Environment, €6.5 million to the Veneto Region, and compensation for nearly 300 civil parties comprised of private individuals and public entities. The judgment also recognized the joint liability of the convicted executives for future cleanup and environmental restoration costs.

Evolving trends in PFAS liability

Among the key arguments raised by the defense were the lack of Italian laws regulating PFAS and the lack of available technologies to detect PFAS at the time of the alleged conduct. However, evidence was introduced at trial indicating that the company had been aware of the toxic, bioaccumulative nature of PFAS since the 1990s. While the legal proceedings are not yet final and the ruling remains subject to appeal, the case already has gained international attention, as it appears to be the first time  individual company executives have been held personally responsible for PFAS contamination.

June’s sentencing follows a historic ruling by the Court of Vicenza recognizing for the first time, a causal link between the death of a Miteni plant worker and his exposure to PFAS. New forms of legal recognition for individuals harmed by PFAS are emerging in international courts, as scientific awareness and litigation efforts expand. In later 2023, Sweden’s Supreme Court held that PFAS in the blood of residents constitutes personal injury.

This case highlights the ever-evolving legal landscape surrounding PFAS liabilities. For further information regarding PFAS and litigation, contact a member of Taft’s Environmental group.

Taft Summer Associate Callia Téllez contributed to this article.

With a new administration in Washington, D.C., the environmental community has been at the edge of its collective seat awaiting word on the fate of one of the most significant elements of EPA’s PFAS Strategic Roadmap – the maximum contaminant levels (MCLs) for selected PFAS. The MCLs, following EPA’s initial – though unenforceable – PFAS Health Advisory Levels – were promulgated on April 10, 2024, and quickly became the cornerstone of EPA’s PFAS regulatory initiative. MCLs not only govern the quality of drinking water, but also are used to derive groundwater standards and clean-up standards across the country.

In a May 14, 2025 press release, EPA gave the first indication of how it intends to proceed.  Significantly, the agency stated that it intends to keep in place the existing MCLs of 4 parts per trillion (ppt) for the two most well-known PFAS – PFOS and PFOA – but will extend the initial compliance deadline from 2029 to 2031. EPA claims that this extension is intended to allow water utilities additional time to install any new treatment technologies needed to meet the standards. Despite keeping the MCLs for PFOS and PFOA, EPA also announced its plan to withdraw other elements of the final April 2024 PFAS MCL rule, specifically the regulatory determinations for PFHxS, PFNA, HFPO-DA (commonly known as GenX), and the Hazard Index mixture of those chemicals plus PFBS, pending possible reintroduction this Spring.

EPA’s plan has been widely reported by the media and environmental organizations as a retreat on efforts to address PFAS in the nation’s drinking water. Yet there are also those in the scientific community who claim that leaving the 4 ppt standards for PFOA and PFOS in effect is extremely significant as it will still drive extensive PFAS reductions nationwide, even if the standards for the other PFAS are temporarily withdrawn. They argue that the PFOA and PFOS standards will still drive the need for new – and expensive – treatment technologies for the vast majority of PFAS-impacted systems across the country, which will significantly reduce overall PFAS levels in drinking water. For example, in data from a group of water treatment systems gathered under the Unregulated Contaminant Monitoring Rule, average PFOA concentrations exceeded the 4 ppt standard in 6% of the systems, and PFOS exceeded the standard in 7.2% of the systems. PFAS National Primary Drinking Water Regulation, 89 Fed. Reg. 32,532, 32,601-02. In contrast, none of the PFAS standards EPA plans to withdraw were exceeded in more than 0.6% of systems. Id. There are those that claim that the types of treatment systems needed to meet the PFOA and PFOS MCLs often also treat other PFAS chemicals found in the water. Thus, they argue that the practical effect of eliminating the MCLs for the other PFAS chemicals may not, at the end of the day, significantly alter the overall net PFAS levels in the nation’s water, as long as water systems are still required to implement the type of treatment necessary to meet the new PFOA and PFOS MCLs.

Similarly, it is also being reported that delaying implementation of the PFOA and PFOS MCLs by an additional two years may not have much impact on the pace at which PFAS levels in drinking water systems are actually lowered. Many drinking water systems are already stating that they will not be able to put treatment systems in place by 2029, regardless of what the MCLs require. Thus, it is being argued that the additional two year reprieve will push back any government enforcement, but not necessarily the pace of the nation’s water system actually reaching the 4 ppt standards.

The Fourth Circuit overturned the remand of two lawsuits Maryland and South Carolina brought against 3M and other PFAS manufacturers. Maryland v. 3M Co., No. 24-1218, 2025 WL 727831 (4th Cir. Mar. 7, 2025). The ruling expands the reach of the federal officer removal statute, making it easier for certain defendants to remove their cases to federal court.

Maryland and South Carolina each brought two PFAS-related lawsuits against 3M: one involving claims arising from AFFF contamination, and another limited to non-AFFF PFAS claims. 3M removed all of the cases to federal court under the authority of the federal officer removal statute, 28 USC Section 1442. The statute allows agencies, federal officers, and “any person acting under that officer” to transfer cases to federal court. To qualify, a private defendant must plausibly allege three elements: “(1) that it acted under a federal officer, (2) that it has a colorable federal defense, and (3) that the charged conduct was carried out for or in relation to the asserted official authority.” Anne Arundel Cnty., Maryland v. BP P.L.C., 94 F.4th 343, 347–48 (4th Cir. 2024) (quoting Mayor & City Council of Baltimore v. BP P.L.C., 31 F.4th 178, 228 (4th Cir. 2022)). The third element is known as the nexus requirement.

3M claimed the federal officer removal statute applied because it produced AFFF for the United States military. Maryland and South Carolina sought to avoid this basis for removal by filing the non-AFFF PFAS lawsuits, arguing that because the states are not seeking recovery from AFFF contamination in those lawsuits, there is no relationship between the charged conduct and the federal authority. The respective district courts agreed and remanded the cases to state court. 3M’s appeals were consolidated before the Fourth Circuit.

The Fourth Circuit vacated the remand, holding that where AFFF and non-AFFF PFAS are commingled, determining the scope of non-AFFF PFAS contamination will inherently require assessing the extent of AFFF contamination—a determination best suited for federal district court. In reaching its decision, the court relied on the Seventh Circuit’s decision in Baker v. Atlantic Richfield Company, which held that the question of whether a company’s pollution stems from its work for the federal government or more general manufacturing operations is a factual question that a federal trial court should decide. 962 F.3d 937, 943–44 (7th Cir. 2020).

The Fourth Circuit’s decision follows on the heels of the Seventh Circuit’s decision to remand the state of Illinois’s case against 3M. People ex rel. Raoul v. 3M Co., 111 F.4th 846, 848–49 (7th Cir. 2024). There, Illinois agreed it would not seek liability for “mixed PFAS contamination”—that is, sources contaminated with both AFFF and non-AFFF PFAS. Maryland and South Carolina refused to make a similar concession in this case. As a result, the Fourth Circuit believed that the factfinder will need to determine how much of the PFAS contamination stems from AFFF versus non-AFFF sources. The Fourth Circuit concluded that the complexity of unraveling those questions confirmed that 3M’s federal work is “inextricably related” to the charged conduct.

Ultimately, the Fourth Circuit ruled that 3M had satisfied the nexus requirement and remanded the case to the respective district courts to assess the remaining elements. In dissent, Judge Henry F. Floyd warned that the majority’s decision expands the nexus requirement too far. An allegation that pollutants are commingled, without more, presents a connection that is “too tenuous to support removal jurisdiction.” The majority’s decision requires defendants to make only the “slightest connection” between the claims and the work the defendants performed for the federal government.

It is likely that some PFAS or AFFF manufacturers will try to rely upon the Fourth Circuit’s decision to argue that any PFAS contamination must necessarily be inextricably commingled with AFFF-derived PFAS, thereby satisfying the nexus requirement for removal. It remains to be seen whether other courts will embrace such an expansive interpretation of removal principles. For help navigating PFAS litigation, contact a member of Taft’s Environmental group.

Those required to comply with certain reporting and recordkeeping requirements for per- and polyfluoroalkyl substances (PFAS) under the Toxic Substances Control Act (TSCA) have been afforded an eight-month delay, shifting reporting to commence July 11, 2025, and be completed by Jan. 11, 2026. Reporting was supposed to commence Nov. 12, 2024, before this delay was announced by the Environmental Protection Agency (EPA). The delay is driven by funding shortages leading to delays in the reporting software development.

Under the rule, persons that manufacture or have manufactured or imported PFAS and PFAS-containing articles in any year since Jan. 1, 2011, are required to report to EPA PFAS uses, production volumes, byproducts, disposal, exposures, and existing information on environmental or health effects. The reporting rule is intended to allow EPA “to better characterize the sources and quantities of manufactured PFAS in the United States.”

In the direct final rule extending the reporting deadlines, EPA indicated that it did not anticipate receiving adverse comments on the extensions but, if it did, it would withdraw the direct final rule allowing for the extension. The direct final rule is open for comment through Oct. 7, 2024. Given that the EPA identified that a five percent reduction to the TSCA program’s 2024 budget was resulting in the EPA making “difficult choices” on priorities, it is not clear how the agency would achieve the software deployment by Nov. 12, 2024, if it withdraws the direct final rule due to adverse comments.

Under the EPA’s definition of PFAS, the EPA has identified at least 1,462 PFAS for possible reporting under TSCA. This extension, if it holds, will allow more time for manufacturers to gather the necessary information to be ready for reporting submissions on July 11, 2025. The additional time will also allow for more outreach to these manufacturers to ensure that those affected by the reporting requirements are aware of them and able to familiarize themselves with the applicable requirements.

New Jersey, North Carolina, and New Mexico are urging the U.S. Environmental Protection Agency (EPA) to add four PFAS chemicals—PFOA, PFOS, PFNA, and GenX—to the list of Hazardous Air Pollutants (HAPs) under the Clean Air Act. The Petition highlights the environmental and health risks posed by PFAS, particularly their persistence in the atmosphere and potential to contaminate soil and water.

While these chemicals are best known for their contamination of drinking water, the release of PFAS into the air has become an increasing concern. According to the Petition, airborne PFAS can settle on land or water bodies, leading to the same contamination problems seen in groundwater, but over potentially wider areas.

The Petition and Its Key Points

The Petition outlines the dangers of PFAS emissions from industrial sources and requests that the EPA formally recognize them as HAPs under the Clean Air Act. If this request is approved, industries that release PFAS into the atmosphere would be subject to stricter regulations aimed at controlling and reducing emissions. Specifically, these industries would have to adopt Maximum Achievable Control Technology (MACT) standards, requiring them to limit emissions to the lowest feasible levels using the best available technology.

The Petition highlights that airborne PFAS emissions contribute to widespread environmental contamination, affecting both air and water quality. It also stresses that these pollutants do not break down naturally and can travel significant distances, leading to far-reaching impacts. Listing PFAS as HAPs would require industries to report their emissions, install advanced emission control technologies, and undergo more rigorous permitting processes.

Health and Environmental Impact

The health risks associated with PFAS exposure are well-documented, including cancer, liver toxicity, and developmental issues in children. In particular, PFOA and PFOS—two of the four PFAS named in the petition—have been studied extensively and are linked to severe long-term health effects. GenX and PFNA, though less widely studied, are believed to pose similar risks.

By tackling PFAS through the lens of air pollution, the Petition takes a broader view of the risks these chemicals pose, recognizing that PFAS emissions can contribute to contamination beyond localized water sources. The states argue that regulating PFAS emissions under the Clean Air Act is a necessary step in protecting public health and preventing the chemicals from entering the environment through multiple pathways.

Overall, the Petition underscores the urgency of addressing PFAS pollution from all angles, including air emissions, and represents a new frontier in the regulation of PFAS. The Petition highlights the growing concern regarding the presence of PFAS in more than just drinking water and the associated impacts to human health and the environment. For further information regarding PFAS in pesticides, contact a member of Taft’s Environmental group. 

EPA is requiring additional testing at sites subject to the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA, or Superfund) five-year review based on PFAS standards issued under the Safe Drinking Water Act (SDWA).

In April 2024, EPA finalized a rule designating two of the most studied and prevalent PFAS,  Perfluorooctanoic acid (PFOA) and Perfluorooctane sulfonic acid (PFOS), as hazardous substances under CERCLA. The rule was published May 8, 2024, and became effective July 8, 2024. 40 CFR § 302.4(a). As a consequence of the designation, owners or operators of a facility or vessel where PFOA or PFOS are released are responsible for the reporting, investigation, remediation, and monitoring requirements under CERCLA.

An important issue raised by the designation is whether previously remediated sites will be reopened for testing of PFOA and PFOS. In a question and answer document EPA released with the finalized rule, EPA stated it would not require sampling from National Priority List (NPL) sites that are designated final or deleted. However, it left the door open to evaluating PFAS levels at sites subject to five-year reviews.

Five-year reviews are required when a remedial action results in any hazardous substances, pollutants, or contaminants remaining at the site “above levels that allow for unlimited use and unrestricted exposure.” 42 USC § 9621(c); 40 CFR § 300.430(f)(4)(ii). The purpose of the review is to “assure that human health and the environment are being protected by the remedial action being implemented.” 42 USC § 9621(c). As part of the review, EPA ultimately issues a “protectiveness statement” describing the extent to which the remedies are still protective and whether any additional remedies are needed.

EPA has indicated it may expand the risk assessment for a site when there is a new exposure pathway, a new potential contaminant of concern, or an unanticipated byproduct of the remedy. The risk assessment determines the risks to human health and the environment by contaminants at a site and informs the development of response actions. 40 CFR § 300.430(d)(1). By expanding the risk assessment, the agency would take a fresh look at the site to determine if any further remedial actions are necessary to protect human health and the environment.

EPA has required PFAS testing at many sites subject to five-year review in the past. However, recent EPA actions have changed the scope of the five-year review for PFAS contaminants in two major respects: (1) the designation of PFOA and PFOS as hazardous substances under CERCLA lowers the threshold finding EPA is required to make before initiating a removal action; and (2) the setting of maximum contaminant levels (MCLs) and maximum contaminant level goals (MCLGs) of certain PFAS under the SDWA has established a potential cleanup standard.

Threshold Finding

EPA’s authority to remedy a site depends on the nature of the contaminants and the threat to public health and the environment. Whereas a release or threatened release of a hazardous substance triggers a removal action when there is a “threat to public health or welfare of the United States or the environment,” a finding of “imminent and substantial danger to the public health or welfare” is required upon the release or threatened release of a pollutant or contaminant. 40 C.F.R. § 300.415(b)(1); 42 USC § 9604(a)(1). So, the threshold finding for hazardous substances requires only a “threat”, while pollutants or contaminants require “imminent and substantial danger”. Thus, the threshold finding for hazardous substances is much lower than for pollutants or contaminants.

Sites with PFOA and PFOS could be subject to removal actions at a much higher rate than before. Other PFAS chemicals could also be subject to removal actions, but EPA would have a higher bar to meet. Also, exceedances of the drinking water standards may serve to justify a finding of a “threat” or “imminent and substantial danger” to public health or welfare.

Cleanup Standards

Under CERCLA, the remedial action chosen for the site is required to attain the “legally applicable or relevant and appropriate standard, requirement, criteria, or limitation” (ARAR) under any federal environmental law, including the SDWA. 42 USC § 9621(d)(2). Where “appropriate under the circumstances,” the MCLG is required. Id. In April 2024, EPA finalized the National Primary Drinking Water Regulation (NPDWR) for PFOA, PFOS, Perfluorohexane sulfonate (PFHxS), Perfluorononanoic acid (PFNA), and Hexafluoropropylene Oxide Dimer Acid (HFPO-DA, or GenX) pursuant to the SDWA. This regulation set MCLs and MCLGs for each of the listed PFAS chemicals, as well as a hazard index for mixtures.

EPA now has cleanup standards for the five PFAS chemicals addressed in the NPDWR. Whether the MCLs or MCLGs are appropriate will depend on the unique circumstances of each site.

EPA Five-Year Reviews

In conducting five-year reviews since the CERCLA rule went into effect, EPA regional offices have cited the MCLs as a basis for further testing. For example, at the 57th and North Broadway Streets Superfund Site in Sedgwick County, Kan., additional sampling was recommended in light of the MCLs based on the site’s history of automotive salvage, oil refining, and production of industrial finishes and coatings.

Even where PFAS concentrations at a site are above the MCLs, a response action is not automatically triggered. At the Saco Tannery Waste Pits Superfund Site in York County, Maine, EPA noted that while groundwater PFAS concentrations were above the MCLs, EPA did not identify any of the PFAS as contaminants of concern. EPA indicated that it will conduct a remedial investigation to determine if a PFAS source exists on the site and if there is any migration to private wells. At the Baird & McGuire Superfund Site in Norfolk County, Mass., EPA noted that groundwater PFAS levels exceeded the MCLs but issued a short-term protective determination based on the groundwater controls in place at the site. EPA wanted to conduct further PFAS testing to determine the extent of PFAS contamination.

Based on the above sampling of five-year reviews, EPA is gathering more information to determine the extent and impact of PFAS contamination at various sites. It is unclear when and if exceedances of the MCLs will trigger additional remedies, and whether EPA will require sites to meet the MCLs. Generally, additional remedies will not be necessary if the current remedies are adequately addressing PFAS as well as other contaminants. However, additional remedies may be required if the current remedies are not sufficiently containing a PFAS source.

It is important to note that the MCLs will not be the appropriate standard in most circumstances. Whether the MCLs are appropriate depends on the circumstances at the site, but any remedy must at least assure “protection of human health and the environment.” 42 USC § 9621(d)(1). MCLs set the standard for PFAS levels in drinking water, so they would not properly apply to PFAS concentrations in soil. Similarly, the MCLs would not apply to water that is not going to be used as drinking water.

Past and current owners and operators of industrial properties should be aware that EPA may use the MCLs as the benchmark for PFAS concentrations at many sites, potentially leading to the reopening of previously remediated sites. For help navigating federal and state PFAS laws, contact a member of Taft’s Environmental group.

On July 24, 2024, Environmental Health Perspectives (EHP) published a study relating to the presence of per- and polyfluoroalkyl substances (PFAS) in pesticide products. PFAS are a class of manmade chemicals used for decades in industrial/consumer products because of properties like resistance to heat, fire, stains, and water. PFAS have been linked to serious health concerns, such as cancer, and have been detected in water, soil, air, food, household and workplace materials, and human blood across the world.

The study concludes that nearly 25% of all U.S. pesticide active ingredients are organofluorines (organic compounds that contain a carbon–fluorine bond) and 14% are PFAS. PFAS are a type of organofluorine or fluorinated molecule. For “active” ingredients approved by EPA within the last 10 years, the study finds that 61% are organofluorines and 30% are PFAS. For “inert” pesticide ingredients approved by EPA, the study finds a seemingly limited presence of PFAS but notes there is a significant lack of information on this issue. Furthermore, the study finds that leaching of PFAS from fluorinated containers into pesticide products is a significant contributor to the presence of PFAS in pesticides. Study, p. 1.

In light of the foregoing, the authors of the study make several recommendations, including: (1) more stringent government agency risk assessment for fluorinated pesticides; (2) transparent disclosure of inert ingredients on pesticide labels; (3) a phase-out of post-mold fluorination of plastic containers; and (4) environmental monitoring and biomonitoring of all PFAS pesticides to gather timely data on their bioaccumulation and potential impact on human and ecosystem health. Id.

The Study’s Findings

The authors state they designed their study to analyze the various ways pesticide products can include PFAS, the extent of PFAS contamination in pesticide products, and the associated implications of PFAS in pesticide products on human health and the environment. Id. at p. 2.

The authors studied 471 unique and conventional active ingredients for pesticides registered by EPA and found that 23% of these ingredients are organofluorines and 14% meet the Organisation for Economic Cooperation and Development’s (OECD) definition for PFAS. OECD defines PFAS as “fluorinated substances that contain at least one fully fluorinated methyl or methylene carbon atom (without any H/Cl/Br/I atom attached to it).” A New OECD Definition for PFAS. This definition includes almost any chemical with at least one perfluorinated methyl or perfluorinated methylene group. The authors also studied 54 conventional active ingredients approved in the last 10 years, finding that 61% of these ingredients are organofluorines and 30% meet OECD’s definition of PFAS. Study, p. 3.

Through a public records request to EPA, the authors of the study learned that EPA previously identified 24 approved inert ingredients as PFAS or suspected PFAS. The authors found that EPA cancelled 12 of these ingredient approvals and that one ingredient did not have any carbon-fluorine bonds, concluding that 11 currently approved inert pesticide ingredients contain organofluorines. Of these 11 organofluorine inert ingredients, the authors found that 8 meet the OECD definition of PFAS. Id. at p. 4.

The study also analyzes the presence of PFAS in pesticides through leaching from fluorinated high-density polyethylene (HDPE) containers. The study notes that EPA found that fluorinated HDPE containers can leach perfluorinated carboxylic acids (PFCAs), a subset of PFAS, into pesticides stored in such containers. The authors conclude that roughly 20% to 30% of all hard plastic containers used in the agricultural sector are fluorinated. Id. at p. 6.

The authors also studied the consequences of PFAS in pesticides, finding that: (1) negative impacts to the immune system is one of the most significant adverse effects to humans from PFAS exposure; (2) PFAS is highly stable in the environment and will persist in the environment essentially forever; (3) PFAS active ingredients are present throughout the country in streams, lakes, and rivers; and (4) PFAS active ingredients can contaminate drinking water. Id. at pp. 6-10.

The Study’s Recommendations

In light of its findings, the study recommends the following:

  1. The practice of post-mold fluorination of plastic containers should be discontinued and substituted with other options that do not use fluorine or an in-mold fluorination process found not to produce PFAS;
  • The U.S. and other countries should require disclosure of all pesticide ingredients on pesticide labels and safety data sheets (SDSs);
  • EPA should issue a data call-in for any pesticide ingredients that do not have immunotoxicity studies;
  • All PFAS pesticides should be evaluated for environmental persistence, and the most persistent PFAS pesticides should be mitigated/replaced;
  • The U.S. should expand environmental monitoring and biomonitoring programs to include all PFAS pesticides;
  • EPA should assess the cumulative impacts from fluorinated degradants common to active ingredients and how fluorinated pesticides can impact total fluorine in the environment and food. Id. at p. 10.

This study highlights the growing public awareness and concern regarding the presence of PFAS in pesticide products and the associated impacts to human health and the environment. For further information regarding PFAS in pesticides, contact a member of Taft’s Environmental group.