Indiana allows treated sewage sludge (biosolids) to be applied to farmland but currently lacks reporting or specific limits for PFAS, a large family of persistent “forever chemicals.” Since January 2025, roughly 202,000 dry tons have been spread on about 28,000 acres. The EPA has reopened public comments on regulating PFAS in biosolids while state lawmakers and researchers debate testing, source controls and disposal options to protect farms and waterways.
‘Forever Chemicals’ on Indiana Farmland: How PFAS From Biosolids Reach Fields and Waterways
'Forever chemicals' are on Indiana's farmlands. Here's how they got there
Sewage sludge — a byproduct of wastewater treatment that is often dried and repurposed as fertilizer — is routinely applied to agricultural fields in Indiana and across the United States. When prepared for land application, this material is called biosolids. In Indiana, biosolids are managed under permit rules intended to protect public health and the environment, but advocates say important gaps remain when it comes to per- and polyfluoroalkyl substances (PFAS), often called “forever chemicals.”
What Are PFAS?
PFAS are a large family of more than 21,000 man-made compounds. Many contain strong carbon–fluorine bonds that resist breakdown, allowing the chemicals to persist for decades in soil, water and living organisms. Their widespread use has led to detections from Arctic snow to human placentas, and several PFAS are linked to health concerns.
How Biosolids Enter Agricultural Landscapes
Biosolids are applied to fields to recycle nutrients and organic matter, and they are regulated in Indiana with limits on some pollutants and requirements about application sites and crops. However, Indiana currently has no statewide reporting requirement or regulatory limit specifically for PFAS in biosolids, according to the Indiana Department of Environmental Management (IDEM).
Federal Action and the Regulatory Debate
The U.S. Environmental Protection Agency (EPA) currently regulates six PFAS under its drinking-water program. In July the agency reopened a public comment period to gather input on potential limits for certain PFAS present in biosolids. In a statement, EPA Assistant Administrator Jess Kramer said,
"One of EPA's top priorities is to Make America Health Again, and reducing risk from PFOA and PFOS in biosolids is a critical part of that effort."
State-Level Proposals and Local Numbers
Since January 2025, Indiana records show roughly 202,000 dry tons of biosolids have been applied to about 28,000 acres of land. In 2025, State Representative Maureen Bauer proposed legislation that would have capped PFAS concentrations in biosolids destined for farmland at 100 parts per billion (ppb). Bauer, who farms and served on the legislature’s agriculture committee, said she favors regulation and clear labeling over a statewide ban.
What Researchers Have Found
Purdue University researchers who have studied PFAS for years emphasize the chemicals’ complexity and persistence. Linda Lee led a study in Tippecanoe County that tested more than 100 wells for roughly 50 PFAS compounds and found generally low concentrations in groundwater. However, Lee and colleagues detected PFAS more frequently in surface waters — rivers, streams and tributaries — which can reflect multiple sources including wastewater treatment plants, industrial discharges and agricultural drainage systems (tiling).
Tradeoffs and Practical Challenges
Advocates and researchers highlight difficult tradeoffs: limiting PFAS in biosolids reduces one pathway of environmental contamination, but contaminated sludge still requires disposal — potentially in landfills or incinerators — which carries its own risks. Desi Rybolt of Indiana Conservation Voters said the most effective long-term solution is to reduce PFAS at the source.
Ty Hoskins, a Purdue researcher, noted that companies applying biosolids are trying to comply with regulations and serve farmers’ needs, and that policy must balance agricultural benefits with contamination risks. Gretchen Salter of Safer States said testing is the clearest first step for states, and pointed to Maine’s remediation fund as a model that helps farmers avoid shouldering cleanup costs alone.
Moving Forward
Experts and advocates generally agree on two priorities: expand testing and monitoring to clarify where PFAS are present, and pursue upstream controls to limit the use and release of these persistent chemicals. In the near term, policymakers must weigh testing, limits, labeling and financial support for farmers to manage contaminated biosolids without unfairly penalizing agriculture.
Contact: Karl Schneider, IndyStar environment reporter. IndyStar’s environmental reporting is supported by the Nina Mason Pulliam Charitable Trust.
Help us improve.
