Communities and federal agencies are waking up to the dangers of “forever chemicals” in wastewater treatment sludge, which is often sprayed on farm fields as fertilizer. In mid-January, the federal Environmental Protection Agency warned that this practice endangers human health. A month later, Johnson County in northeast Texas declared a state of emergency over the contamination of farm fields with per- and polyfluoroalkyl substances, or PFAS, from sewage sludge. John Scott, a research scientist at the Illinois Sustainable Technology Center who studies PFAS in wastewater treatment facilities and landfills, spoke with News Bureau life sciences editor Diana Yates about the problem.