PFAS in Agriculture: Science, Uncertainty, and Risk Communication

Per- and polyfluoroalkyl substances (PFAS), often called "forever chemicals," have become one of the most consequential environmental and regulatory challenges facing American agriculture. Farmers, composters and rural communities find themselves at the center of a crisis largely not of their making: agriculture sits downstream from industrial contamination sources, yet farmers and food producers bear disproportionate regulatory, economic and reputational consequences when PFAS are detected in soils, crops, water or food.

The central flaw in current PFAS governance — treating a chemically diverse class of thousands of compounds as a single, uniform hazard — is especially damaging to agriculture. It distorts regulation, amplifies public alarm about food safety and exposes farmers to liability and market consequences poorly calibrated to actual risk.

The presence of PFAS in agricultural soils or food at trace levels does not, by itself, establish meaningful harm. Real-world risk depends on the specific compound, dose, duration and exposure pathway.

Depending on the definition used, PFAS inventories include thousands to tens of thousands of substances. EPA's CompTox PFAS structure list contains 21,028 in its January 2026 update. No single PFAS definition has been agreed to, including for agricultural purposes — a point with direct consequences when state proposals could sweep fluorinated pesticides into PFAS restrictions without first evaluating exposure, mobility, persistence or agricultural need.

Since the 1940s, PFAS have been used in hundreds of applications because of their resistance to heat, water, oil and chemical degradation — from firefighting foams and nonstick cookware to semiconductors, medical devices and batteries. Some, including certain fluoropolymers, are less soluble and less mobile. Others, including PFOA and PFOS, move readily in water, persist in the environment and have a stronger evidence base for adverse health and ecological effects.

Hazard vs. Risk

Hazard describes a substance's capacity to cause harm under some conditions. Risk depends on how much, how often, for how long and by what pathway someone is exposed. Measurability is not the same as harmfulness: modern analytical tools can detect compounds at concentrations far below many established health thresholds.

Children warrant separate consideration. The same concentration in water or food delivers a larger dose relative to body weight while organ systems are still forming, and early-life behaviors can increase contact with PFAS-bearing dust and materials.

EPA has used the Safe Drinking Water Act to set national drinking-water requirements for some PFAS, the Toxic Substances Control Act to require broad reporting on PFAS in commerce, and CERCLA to designate PFOA and PFOS as hazardous substances, expanding cleanup liability. The federal baseline remains unsettled: EPA retained the 2024 maximum contaminant levels for PFOA and PFOS but in 2025 announced its intent — formally proposed in 2026 — to extend compliance deadlines and to rescind and reconsider standards for PFHxS, PFNA, HFPO-DA (GenX) and the Hazard Index mixture.

States supply much of the implementation detail, especially for soils, biosolids, compost, waste streams and agricultural interfaces. Producers operating across state lines, or selling into multiple state markets, face a patchwork of requirements.

The center of PFAS litigation remains the AFFF multidistrict litigation in the U.S. District Court for the District of South Carolina, focused principally on firefighting-foam contamination. In June 2023, Chemours, DuPont and Corteva agreed to contribute $1.185 billion to resolve PFAS drinking-water claims brought by a nationwide class of public water systems.

Personal-injury claims remain more difficult, because causation often depends on individualized proof of exposure, dose and medical harm. Medical-monitoring claims remain highly state-specific.