Can PFAS from sewage sludge fertilizer contaminate food crops and raise cancer risk?

What's actually in it

Biosolids (treated sewage sludge) are used as fertilizer on farmland across the US and many other countries. These biosolids contain PFAS from industrial wastewater, household cleaners, nonstick cookware residues, and personal care products that all end up in the sewer system. When spread on farm fields, PFAS transfer from soil into the roots and tissues of food crops.

The crops look perfectly normal. You can't see, smell, or taste the PFAS in them.

What the research says

A 2026 analysis in Environ Sci Technol assessed the cancer risk from PFAS entering the US food supply through biosolid-fertilized cropland. The researchers measured PFAS concentrations in biosolids, modeled uptake by common food crops, and calculated the resulting human dietary exposure.

The analysis found that PFAS levels in crops grown on biosolid-treated fields were measurably higher than crops from untreated fields. Leafy greens and root vegetables accumulated the most PFAS, while grain crops accumulated less.

When the researchers calculated lifetime cancer risk from eating these contaminated crops, the numbers exceeded acceptable risk thresholds for people who regularly eat produce from biosolid-treated farms. PFOS and PFOA contributed the most to cancer risk.

Currently, there are no federal limits on PFAS in biosolids in the US. Until regulations catch up, buying from farms that don't use biosolid fertilizer, choosing organic when possible, and washing produce thoroughly can help. Growing your own food in clean, tested soil is another option.