The National Academies of Sciences, Engineering, and Medicine (NASEM) has published a report on per- and polyfluoroalkyl substances (PFAS) in agricultural systems to help guide the U.S. Department of Agriculture’s (USDA’s) response to the impacts of agricultural lands polluted by these “forever chemicals.”

The PFAS Problem: Lasting Environmental Damage and Human Harm

Often called “forever chemicals” due to their inability to break down in the environment or human body over time, PFAS are a diverse family of synthetic compounds used in numerous consumer and industrial products, including nonstick cookware, textiles, packaging, and firefighting foams. The exact number of PFAS is unknown, but by some estimates, there are more than 14,000.

Once introduced to the environment, PFAS continue to accumulate in soil, surface and ground water, and air, leading to their contamination of crops, food animals and their products, and drinking water, and subsequently, resulting in human exposure.

The body of evidence demonstrating the harms PFAS pose to human and environmental health is growing. Many health conditions—including cancers and thyroid and cardiovascular diseases—are associated with PFAS exposure, and more are suspected. The World Health Organization (WHO) has declared two types of pervasive PFAS—perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS)—as carcinogenic and possibly carcinogenic to humans, respectively.

“Forever Chemicals” on Agricultural Land

In agricultural settings, PFAS contamination of soil and water can render farmland unusable for crops or grazing if there are no viable mitigation options. There are cases in the U.S. and globally of farms where PFAS have moved from groundwater and soil into the drinking water, forage, and feed of livestock, causing PFAS levels in animals to be so great that their milk and meat products were declared unsafe for human consumption.

Some instances of PFAS contamination in agricultural systems can be linked to a known source, but pollution can also originate from diffuse sources or the introduction of contaminated offsite materials. At present, much remains unknown about the extent, types, toxicity, and concentrations of PFAS in the environment, and there are few viable options for addressing contamination.

Developing Science and Emerging Solutions for PFAS Remediation

Trapping and Sequestering PFAS

Emerging research on PFAS mitigation in agricultural systems is beginning to identify potential strategies to trap, sequester, or reduce PFAS mobility. Sorbent-based approaches are among the most advanced. While designer sorbents show strong bench-scale performance, their cost and scalability limit widespread agricultural use. Biochar has therefore become a leading candidate, with its sorptive capacity influenced by feedstock, pyrolysis temperature, surface area, and carbon-to-oxygen ratios. High-temperature biochars can achieve near-complete removal of long‑chain PFAS and, in some cases, show performance close to that of activated carbon for short‑chain compounds. Amendments using iron salts or oxides may further increase sorption but raise cost and reduce yield. However, much of this evidence is laboratory-based; key uncertainties remain around long-term field performance, desorption potential, incorporation depths, and performance across soil types. Other abundant sorbents, such as modified clays and water treatment residuals, show promise but need field validation and cost–benefit assessment.

Water Management

In water management, conservation tools adapted from nutrient control offer new opportunities. Removal structures, such as ditch filters, modular boxes, and tile-drain filters, can be packed with PFAS-targeted media and sized to hydrologic conditions. Effective design requires matching sorbents to local PFAS profiles, accounting for media kinetics, flow rates, and the potential release of co-contaminants. Because PFAS vary widely by chain length and functional group, PFAS-specific design manuals may be required to improve installation reliability. De-nitrifying bioreactors presents a complementary option, although PFAS degradation via de-nitrifying microbes remains slow and incomplete. Other emerging innovations being studied include pairing microbial processes with abiotic catalysts and adding biochar to extend residence time and enhance PFAS retention.

Crop Uptake and Accumulation

Regarding plants, current research is exploring how crop characteristics influence PFAS uptake, with the goal of either minimizing PFAS in harvested crops or maximizing uptake for phytoremediation. Transpiration rate appears to be a major driver of PFAS accumulation, while root structure, lipid and protein content, and root exudates may also shape uptake differences among species. Still, field-based, multi‑year data are limited, and little is known about how conservation practices such as tillage, rotation, density, and irrigation influence PFAS uptake. Another knowledge gap is the selection of vegetative covers to avoid wildlife exposure risks.

Mitigation in Livestock

Managing PFAS in livestock presents additional challenges. Animals can accumulate PFAS from feed and water, with dairy pathways being especially critical. Limited data suggest PFOS levels in milk and beef decline within 8–12 weeks after exposure ends, and switching to clean feed or diluting contaminated feed can reduce risks. However, research on broader PFAS compounds, updated pharmacokinetic models, and manure management strategies is urgently needed.

Existing USDA Assistance Pathways and Opportunities to Address PFAS

USDA provides several technical and financial assistance programs that could help address PFAS contamination on agricultural lands, primarily through the Natural Resources Conservation Service (NRCS) and the Farm Service Agency (FSA). While NRCS focuses on conservation planning and technical support for working lands, FSA offers financial incentives to retire environmentally sensitive land. Among these programs, the Environmental Quality Incentives Program (EQIP) currently presents the broadest opportunities for addressing PFAS due to its extensive use, comprehensive practice coverage, and substantial cost-share options. The Conservation Stewardship Program (CSP) may further advance PFAS-related conservation through funding enhancements to existing practices. The Conservation Reserve Program (CRP) may offer another pathway by retiring contaminated land and mitigating PFAS impacts through vegetative covers, pilot projects, or partnerships.

Despite this potential, NASEM identified practical barriers, such as program oversubscription, eligibility constraints, and producers’ reluctance to pursue assistance due to concerns about attracting regulatory attention. Additionally, some conservation practices can yield mixed results in the PFAS context; for example, erosion control may reduce surface transport but increase leaching to groundwater, while the use of imported soil amendments could inadvertently introduce PFAS.

USDA could integrate PFAS into existing conservation frameworks either by including them under current resource concerns or by establishing PFAS as a standalone concern. The latter approach may enable more targeted evaluation of practices, but could also make landowners uneasy about being targeted for PFAS. USDA-NRCS could also update or expand practice standards to reflect PFAS risks; at present, only the Soil Carbon Amendment standard explicitly references PFAS.

A major challenge is the limited data on PFAS presence, sources, and behavior in agricultural settings, compounded by the absence of a working agricultural definition for PFAS. Federal guidance on thresholds would help contextualize contamination, though the supporting science is still developing. Predictive modeling, which is already used to map groundwater PFAS risk, could help identify vulnerable agricultural lands when site-specific data are lacking.

Overall, while knowledge gaps persist, existing conservation programs and planning processes offer meaningful opportunities for USDA to support producers in managing PFAS risks. Enhanced federal guidance and expanded data collection would further strengthen these efforts.