The challenge of PFAS contamination of biosolids spans testing, disposal, treatment, migration to groundwater and drinking water sources, and the risk of PFAS uptake in crops and animals. This article explores the shifting legal frameworks surrounding PFAS, zeroing in on their presence in agricultural biosolids. It addresses some potential ramifications of PFAS in biosolids for stakeholders, from farmers to municipalities and other wastewater treatment plant operators. With PFAS contamination emerging as an issue across the spectrum of environmental law, the environmental, public health, and legal stakes of understanding their presence in agricultural biosolids and the soil of our nation’s farmland are high.
PFAS are a group of synthetic chemicals known for their resistance to heat, water, and oil. Perfluoroalkyl and Polyfluoroalkyl Substances (PFAS), Nat’l Inst. of Health (May 3, 2024) [hereinafter NIH, PFAS]. This resistance makes them valuable in various industrial applications such as firefighting foams, nonstick cookware, water-repellent clothing, and food packaging. PFAS have been used since the 1940s in thousands of applications across industries and consumer sectors. These same properties render PFAS persistent in the environment and human body, earning them the nickname “forever chemicals.” Destroying them is a difficult ordeal as their fluorine-carbon bond is the most stable bond in organic chemistry. Id. However, the stable molecular bonds that make the chemicals so useful also make them dangerous and long-lasting, allowing them to bind to blood and tissue, where they can build up over time and contribute to a range of health issues. Our Current Understanding of the Human Health and Environmental Risks of PFAS, EPA (May 16, 2024). Studies have linked PFAS exposure to numerous adverse health effects, including certain cancers, liver damage, endocrine disruption, decreased fertility, and increased risk of asthma and thyroid disease. Id. One study found that 97% of Americans have detectable amounts of PFAS in their blood. Ryan C. Lewis et al., Serum Biomarkers of Exposure to Perfluoroalkyl Substances in Relation to Serum Testosterone and Measures of Thyroid Function Among Adults and Adolescents from NHANES 2011–2012, 12 Int’l J. Env’t Rsch. & Pub. Health 6098 (2015). PFAS contamination extends beyond industrial applications, reaching households through everyday products. PFAS are now ubiquitous, found in air, soil, and water bodies, with our “diet” serving as “the major human exposure pathway for some PFAS” chemicals, making comprehensive management strategies for protecting public health and environmental safety difficult to implement. Amila O. De Silva et al., PFAS Exposure Pathways for Humans and Wildlife: A Synthesis of Current Knowledge and Key Gaps in Understanding, 40 Env’t Toxicology & Chemistry 631 (2021).
PFAS enter wastewater treatment plants from multiple sources. They originate from household products, human waste, industrial discharges, and firefighting foams. NIH, PFAS, supra. Standard wastewater treatment plants are not designed to remove PFAS, allowing these chemicals to concentrate in by-products like biosolids, also known as sludge, sewage sludge, or residuals. Per- and Polyfluoroalkyl Substances (PFAS) in Biosolids, EPA (June 4, 2024). Biosolids are typically treated through processes such as alkaline treatment, composting, or thermal drying to reduce pathogens and volatile organic compounds. Qianhan Le & G.W. Price, A Review of the Influence of Heat Drying, Alkaline Treatment, and Composting on Biosolids Characteristics and Their Impacts on Nitrogen Dynamics in Biosolids-Amended Soils, Waste Mgmt. (Mar. 15, 2024). Regulators and industry groups historically understood these processes as rendering biosolids safe for agricultural use. Previously, activists raised concerns about microplastics and heavy metals in biosolids. However, strong regulations, particularly around pathogens and heavy metal contamination, have largely addressed those concerns, allowing biosolid application to be viewed as a relatively “eco-friendly” method of transforming waste products into soil fertility. From 2016 to 2022, the Environmental Working Group estimated, based on state reports to the U.S. Environmental Protection Agency (EPA), that 19.1 billion pounds of biosolids have been applied across the nation’s farmland. Hayes, supra.
Despite the known benefits of applying biosolids as fertilizers, the presence of PFAS converts an organic boon into a potential peril. The application of biosolids may introduce PFAS to the environment, allowing them to enter surface or groundwater, and there is still much that we don’t know about the migration of PFAS into grazing animals, plant uptake, and other risks of this management approach. Once PFAS-contaminated biosolids are applied, the chemicals can bioaccumulate in crops, including feed crops such as corn and hay, and the animals that eat them. Heather D. Brake et al., Current Per- and Polyfluoroalkyl Substance (PFAS) Research Points to a Growing Threat in Animals, 261 J. of the Am. Veterinary Med. Ass’n 952 (2023). PFAS also can infiltrate into groundwater, contaminating irrigation water used over an even broader area of an agricultural landscape and domestic drinking supply. PFAS Contamination and Soil Remediation (Signal), European Env’t Agency (May 23, 2024). A 2013 study by scientists from the Colorado School of Mines determined that two PFAS chemicals bio-accumulated in lettuce and tomatoes grown in soil after the application of agricultural biosolids. Andrea C. Blaine et al., Uptake of Perfluoroalkyl Acids into Edible Crops via Land Applied Biosolids: Field and Greenhouse Studies, 47 Env’t Sci. & Tech. 14062 (2013). The U.S. Food & Drug Administration notes the risk of PFAS contamination in the food supply for human health. Questions and Answers on PFAS in Food, U.S. Food & Drug Admin. (June 26, 2024). However, it points to its own sampling of American food products and some research studies, which show that “PFAS contamination in the environment where food is grown or produced does not necessarily mean the food will contain detectable levels of PFAS,” to argue that there is not presently great cause for concern. Id. Food safety and environmental advocates, on the other hand, increasingly argue that PFAS entering the food chain poses serious and underregulated health risks to consumers. Molly M. Ginty, “Forever Chemicals” Called PFAS Show Up in Your Food, Clothes, and Home, Nat. Res. Def. Council (Apr. 10, 2024).
Regulatory Framework—Federal Action on PFAS in Agricultural Biosolids
The regulatory framework surrounding PFAS and biosolids is a complex patchwork of state and federal requirements that continue to evolve. The following briefly describes the status of PFAS regulation in biosolids, including recent regulatory developments.
Section 405(d) of the Clean Water Act (CWA) establishes standards for the use or disposal of sewage sludge (biosolids) in 40 Code of Federal Regulations (CFR) Part 503. This provision includes pollutant limits, requirements for pathogen reduction, management practices, and monitoring and reporting requirements. These regulations ensure the screening of biosolids for pathogens and heavy metals like arsenic, lead, and mercury. Land application, including in the agricultural context, has been a popular method of federally approved biosolids disposal management for decades and is the most common method for using biosolids, according to the EPA. Land Application of Biosolids, EPA (Feb. 23, 2024). These regulations do not, however, monitor biosolids for the presence of PFAS and do not limit the inclusion of PFAS in biosolids. Since PFAS compounds were not historically regulated, their potential implications for biosolids application have not been comprehensively understood or litigated.
As concerns about PFAS have mounted in recent years, the regulatory landscape has begun to shift. The Biden administration has intensified efforts to address PFAS contamination, as illustrated by its recent promulgation of regulations addressing PFAS. Some recent regulatory actions and initiatives directly address the issue of PFAS in biosolids. For example, the EPA’s PFAS Strategic Roadmap commits the agency to completing a risk assessment for two PFAS (PFOA and PFOS) in biosolids by December 2024. PFAS Strategic Roadmap: EPA’s Commitments to Action 2021–2024, EPA (May 7, 2024). However, most of the recent regulatory actions have focused on other aspects of concern for PFAS contamination.
For instance, in February 2024, the EPA proposed to amend its regulations under the Resource Conservation and Recovery Act (RCRA) by adding nine specific PFAS substances to its list of hazardous constituents. Listing of Specific PFAS as Hazardous Constituents, 89 Fed. Reg. 8606 (Feb. 8, 2024). This change would unlock the potential for these specific PFAS to be addressed as part of corrective action at RCRA hazardous waste treatment, storage, and disposal facilities. The proposal would not, however, require the full cradle-to-grave management controls often associated with RCRA hazardous waste. While not a full solution, the EPA argues that listing these PFAS as hazardous constituents “is a building block for any future work to regulate PFAS as a RCRA listed hazardous waste.” Proposal to List Nine Per- and Polyfluoroalkyl Compounds as Resource Conservation and Recovery Act Hazardous Constituents, EPA (Apr. 10, 2024). In June 2024, EPA also finalized the first national Maximum Contaminant levels for six PFAS chemicals in drinking water. PFAS National Primary Drinking Water Regulation; Correction, 89 Fed. Reg. 49,101 (June 11, 2024) (to be codified at 40 C.F.R. pt. 141). Under the PFAS National Primary Drinking Water Regulation, public water systems are required to monitor for the six identified PFAS contaminants and provide the public with information on the levels of these PFAS in their drinking water beginning in 2027. It is unclear whether this action would directly impact the problem of PFAS in biosolids, as any new treatment processes brought online at a given wastewater treatment facility may treat wastewater for PFAS only after the wastewater is separated from solid components.
In May 2024, EPA designated the aforementioned PFOS and PFOA hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act (Superfund). Designation of Perfluorooctanoic Acid (PFOA) and Perfluorooctanesulfonic Acid (PFOS) as CERCLA Hazardous Substances, 89 Fed. Reg. 39,124 (May 8, 2024) (to be codified at 40 C.F.R. pt. 302). This designation may be an early step in paving the way for some federal cleanup efforts. However, the scale of biosolid dispersal in the American landscape may make the traditional Superfund cleanup route difficult to implement as a practical matter. The Joint Principles for Preventing and Managing PFAS in Biosolids, developed by the EPA in collaboration with the Environmental Council of the States and the National Association of State Departments of Agriculture, represent another step towards comprehensive management and mitigation. Joint Principles for Preventing and Managing PFAS in Biosolids, EPA (July 24, 2024). The Joint Principles emphasize the importance of interagency cooperation, data sharing, and stakeholder engagement in addressing the PFAS crisis but do not implement new regulatory requirements. The EPA also adopted a final rule in October 2023 to finalize reporting and recordkeeping requirements for PFAS substances under the Toxic Substances Control Act (TSCA). Toxic Substances Control Act Reporting and Recordkeeping Requirements for Perfluoroalkyl and Polyfluoroalkyl Substances, 88 Fed. Reg. 70,516 (Oct. 11, 2023) (codified at 40 CFR pt. 705). This rule requires manufacturers of PFAS to submit certain information regarding their products to the EPA. It may serve to provide important information useful for a broader regulatory scheme at some later time. It does not, however, impact wastewater facilities producing biosolids or users of biosolids, as neither are manufacturers of PFAS.
Measures like these mark significant regulatory progress, but serious gaps remain at the federal level for managing PFAS-contaminated biosolids on agricultural land. For example, most of the research on PFAS and health effects are based on just two types of PFAS (PFOA and PFOS), and much of the regulatory work focuses on a small handful of PFAS types. But there are thousands of varieties of PFAS chemicals used in industry with very different structures and chemical and physical properties. Questions and Answers on PFAS in Food, U.S. Food & Drug Admin. (June 26, 2024). The current wave of regulatory action around PFAS contamination may be just the tip of the iceberg.
Congress also has begun acknowledging and attempting to address the issue with the proposed “Relief for Farmers Hit with PFAS Act.” The Act would direct the U.S. Department of Agriculture (USDA) to designate about $500 million in grants to states, territories, and tribes to monitor and clean up PFAS on farmland and agricultural products. Introduced in March 2023, the bill has not progressed beyond committee.
Critics argue that the pace of federal regulatory action is too slow, given the urgency of the PFAS crisis. The Public Employees for Environmental Responsibility (PEER) has sued the EPA, aiming to force the federal government to take a stricter position on PFAS in biosolids. They argue that the agency has “unlawfully failed to identify at least 18 per- and polyfluoroalkyl substances (PFAS) in biosolids and has failed to promulgate regulations for at least 12 PFAS in biosolids as required under 33 U.S.C. § 1345(d)(2)(C).” Tim Whitehouse, Re: Notice of Intent to File Suit Regarding Alleged Violation of the Clean Water Act (CWA), PEER (Feb. 22, 2024). PEER’s public announcement of the suit argued that “litigation is the only avenue for establishing a concrete and expeditious timeline for stemming what is becoming a threat to America’s food security.” EPA Sued to Remove PFAS from Biosolid Fertilizers, PEER (June 6, 2024).
State Action on PFAS in Agricultural Biosolids
States are subject to federal regulations under 40 C.F.R. Part 503 for biosolid use and disposal but have the authority to make independent decisions about managing biosolids further while complying with the rule. States like Maine and Michigan are acting more urgently than the federal government, setting local standards and initiating tests on agricultural lands to assess PFAS contamination. For instance, in 2022, the Maine legislature banned the use of biosolids altogether after the state identified dozens of contaminated farms, many of which were likely contaminated as part of a state-encouraged drive to spread biosolid wastes from paper mills throughout the 1980s and 1990s, not realizing that the waste was contaminated with PFAS. Shannon Kelleher, Farmers Facing PFAS Pollution Struggle for Solutions, New Lede (Mar. 11, 2024). Maine now offers some financial assistance and support to affected farmers, an initiative that could serve as a national model. Maine’s $65 million PFAS Fund provides financial support, research funding, and options for farmers to sell contaminated lands to the state at fair market value. Fund to Address PFAS Contamination, Me. Dep’t of Agric., Conservation & Forestry. These funds enable farmers to recover from the financial impact of PFAS contamination and invest in safer, more sustainable practices.
Michigan also has taken notable steps by implementing strict pretreatment protocols for industries discharging PFAS into wastewater streams, requiring biosolids to be tested for PFAS and not allowing the use of agricultural biosolids with more than 150 parts per billion of PFAS. Land Application of Biosolids Containing PFAS—Interim Strategy, Mich. Dep’t of Env’t, Great Lakes & Energy (Mar. 2021). These state-level actions highlight the role of local governments in filling regulatory gaps and protecting their communities. However, out of the 34 states that responded to a 2023 survey by the Environmental Council of the States, 27 had no existing or proposed legislation on PFAS in biosolids. Sarah Grace Hughes, PFAS in Biosolids: A Review of State Efforts & Opportunities for Action, Env’l Council of States (Jan. 2023). Indeed, banning agricultural biosolids altogether may not be a popular policy solution in many states. In addition to serving as a fertilizer, land application of biosolids is considered to be a cost-effective way to recycle or dispose of what would otherwise be bulky and difficult-to-utilize waste.
The Liability Landscape
The possible presence of PFAS in agricultural biosolids has ignited significant liability concerns for various stakeholders. Farmers, municipalities, other wastewater treatment plant operations, and companies producing biosolids are increasingly finding themselves at the intersection of litigation and regulation. The complexity of the liability landscape necessitates a nuanced understanding of each party’s responsibilities and risks.
Farmers, municipalities, and other land users that apply PFAS in biosolids to agricultural fields, landscaping, or other land may face the dual risk associated with contaminated crops and subsequent legal action. Food products grown on such lands can carry PFAS, posing potential health risks to consumers and potential market rejection, thus financially crippling the farmers. The FoodPrint of PFAS, FoodPrint (Sept. 11, 2023). Maine already has set a precedent by banning the spreading of PFAS-contaminated biosolids, highlighting the severe impacts on local agriculture. Tom Perkins, Maine Bans Use of Sewage Sludge on Farms to Reduce Risk of PFAS Poisoning, The Guardian (May 12, 2022). So far, however, Maine is the only state that has systematically tested farmland for PFAS. Beyond legal challenges, farmers face significant economic and reputational risks. PFAS contamination can lead to crop loss, decreased land value, and harm to the farmer’s brand and market standing. Zoë Schlanger, Maine Is a Warning for America’s PFAS Future, The Atlantic (Apr. 11, 2024). These financial impacts can be devastating for small-scale farmers, who may lack the resources to absorb such shocks.
PFAS-contaminated wastewater poses significant challenges for wastewater treatment facilities. Advanced wastewater treatment technologies that would fully remove PFAS are being explored, but widespread implementation remains a distant and financially costly goal. Groundbreaking Study Shows Unaffordable Costs of PFAS Cleanup from Wastewater, Minn. Pollution Control Agency (June 6, 2023). Treatment plants must navigate these waters carefully, balancing operational mandates with emerging environmental safety protocols. The financial and legal liabilities for wastewater treatment plants are substantial. The growing potential for lawsuits and regulatory fines can impose severe financial burdens (which often can be passed on to the public, such as through user fees or higher prices) and could divert resources from other essential operations and upgrades. Moreover, negative publicity can erode public trust and complicate future projects. The risk of legal action against water utilities extends beyond commercial agricultural plaintiffs—many public wastewater treatment utilities have longstanding programs to give away or sell biosolids at a low cost to members of the public, including gardeners and landscapers. Michael Hawthorne, Tribune Investigation: Chicago’s Sewage District Fails to Warn Gardeners Free Sludge Contains Toxic Forever Chemicals, Chi. Trib. (June 14, 2024).
Companies and municipalities that sell or give away PFAS-contaminated biosolids, often marketing their product as safe and organic, are also increasingly under scrutiny. For example, the Chicago Metropolitan Water Reclamation District has historically marketed its free compost made with biosolids as a “sustainable and environmentally beneficial product,” distributing it widely to local gardeners, landscapers, and small farmers. Id. Some biosolids users are beginning to take legal action. Synagro Technologies faces a lawsuit that its biosolids contained PFAS, which contaminated and damaged farms in Texas. First Amended Complaint & Election of Jury Trial, Farmer v. Synagro Tech. Inc. (Baltimore Cnty. Cir. Ct., filed Feb. 27, 2024) (No. C-03-CV-24-000598). The lawsuit claims that PFAS-tainted biosolids spread onto their land rendered their farmland “worthless,” made them sick with different illnesses, led to livestock deaths, and contaminated water supplies. Id. The farmers claim that the manufacturer should have done more to warn buyers about the dangers of its products but instead that Synagro “falsely markets” its fertilizers as “safe and organic.” Id. at 3. The case is ongoing.
Remediation Efforts
Remediation of PFAS-contaminated sites presents substantial challenges and costs. Conventional methods often fall short due to PFAS’s extremely durable chemical properties. Swadhina Priyadarshini Lenka et al., A Review of the Occurrence, Transformation, and Removal of Poly- and Perfluoroalkyl Substances (PFAS) in Wastewater Treatment Plants, Water Rsch. (July 1, 2024). Innovative technologies and coordinated efforts will be crucial for effective remediation and prevention of further contamination. Prominent among current strategies is thermal treatment, which involves incinerating contaminated media at high temperatures to break down PFAS compounds. Jay N. Meegoda et al., A Review of PFAS Destruction Technologies, 19 Int’l J. Env’t Rsch. & Pub. Health 16397 (2022). However, this method can be prohibitively expensive and logistically complex for large-scale applications. Id. The idea of incinerating potentially tens or hundreds of thousands of acres of topsoil would pose logistical challenges at best. Serious concerns about the potential release of toxic by-products during incineration exist and would necessitate stringent controls and monitoring. Additionally, current research may be insufficient to address whether PFAS can even be completely destroyed in the incineration process. An EPA technical brief on PFAS incineration stated that “the effectiveness of incineration to destroy PFAS . . . is not well understood.” Per- and Polyfluoroalkyl Substances (PFAS): Incineration to Manage PFAS Waste Streams, EPA (Feb. 2020).
Emerging technologies, such as electrochemical oxidation and bioremediation, offer some avenues for PFAS remediation. Meegoda et al., supra. Electrochemical oxidation involves using electrical currents to break down PFAS in water, while bioremediation leverages microorganisms or plants to degrade PFAS in soil and water. A 2019 trial by the Mi’kmaq Nation in Maine, in partnership with a nonprofit organization, attempted to remediate land contaminated with PFAS from firefighting foam used on a now-defunct Air Force base, using hemp. Certain varieties of hemp plants can have thick stems and grow more than 10 feet in a season, making them, in theory, an ideal method for drawing out and removing toxic chemicals from soil. However, the trial records show that even in the most promising areas, only a maximum of 2% of the PFAS was removed from the soil. Sara L. Nason et al., A Comprehensive Trial on PFAS Remediation: Hemp Phytoextraction and PFAS Degradation in Harvested Plants, 3 Env’l Sci.: Advances 304 (2024). Moreover, there is now an added challenge associated with disposing of the now-contaminated harvested hemp. While these technologies are still in the developmental stages, they may hold the potential for future cost-effective and sustainable PFAS remediation.
The PFAS Issue May Only (Bio-)Accumulate from Here
As science progresses and the regulatory landscape shifts, it is imperative for all stakeholders—from farmers to policymakers to attorneys—to stay informed and proactive on this emerging issue. Looking ahead, the regulatory framework for PFAS is likely to become more stringent and comprehensive. Advances in scientific understanding of PFAS’s health and environmental impacts will drive regulatory changes. Stakeholders must remain adaptive and proactive, engaging in policy discussions and advocating for sensible regulations that balance public health protection with the economic viability of America’s agricultural producers. Effective management of the challenges posed by PFAS-contaminated “toxic terroir” may necessitate increasingly robust regulatory frameworks, technological innovation, legal challenges and disputes, and cooperative efforts to safeguard public health and the environment.
