PFAS in Agriculture: Science, Uncertainty, and Risk Communication

DOI: 10.62300/krpmdc33

Authors:
Jon Entine – Genetic Literacy Project
Mark McDaniel – TechLaw Consultants Inc.
Thomas Redick – Global Environmental Ethics Counsel LLC

Cast Liaison: John Swarthout – Bayer Crop Science

Executive Summary
The authors of this paper survey the federal and state regulatory landscape, review the evolving litigation environment as it affects agricultural actors, and provide guidance for farmers, composters, and agricultural communicators. CAST and land-grant universities must lead in translating complex PFAS science into credible agricultural policy for their stakeholders and the public.

Farmers are partners in risk reduction, not convenient downstream targets for contamination they did not cause. 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—the tendency to treat a chemically diverse class of thousands of compounds as a single, uniform hazard—is especially damaging to the agricultural sector. That flattening of distinctions distorts regulation, amplifies public alarm about food safety, and exposes farmers to liability and market consequences that are 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.

Five core issues relevant to the agricultural community:

• First, the strongest evidence for adverse health effects is concentrated in a small number of well-studied compounds, particularly PFOA and PFOS, and in high-exposure scenarios; the science remains far weaker for most of the thousands of other PFAS.
• Second, agriculture’s primary PFAS exposure pathway is through contaminated inputs—biosolids, compost, irrigation water, and certain feeds—not through farming practices themselves.
• Third, sound agricultural governance requires compound-, pathway-, and exposure-specific analysis, with priority given to upstream source control and targeted testing rather than blanket restrictions on farming activities.
• Fourth, farmers need practical, science-based tools to test inputs, interpret results, communicate credibly with buyers and consumers, and avoid being swept into regulatory or litigation responses calibrated to industrial polluters rather than agricultural recipients.
• Fifth, the EPA’s 2025 Draft Sewage Sludge Risk Assessment and 2026 draft biosolids guidance sharpen the practical question for agriculture: biosolids remain a valuable and often necessary nutrient source, but PFOA/PFOS management now requires source control at wastewater treatment plants, targeted testing, crop- and pathway-specific land application decisions, and clearer public communication rather than blanket reassurance or prohibition (EPA Biosolids Guidance 2026).
  
  The 2026 National Academies of Sciences, Engineering, and Medicine (NASEM) report prepared for USDA/ NRCS—”PFAS in Agricultural Systems: Guidance for Conservation Programs at USDA”—reinforces this framework, emphasizing that PFAS on agricultural land should be managed through conservation planning, source and pathway analysis, and decision-making under uncertainty rather than through undifferentiated class-wide assumptions (NASEM 2026).