Sludge, which is lightly treated and marketed as “biosolids”, is used by consumers to fertilize home gardens, and the PFAS levels raise concerns that the chemicals are contaminating vegetables and harming those who eat them.“Spreading biosolids or sewage sludge where we grow food means some PFAS will get in the soil, some will be taken up by plants, and if the plants are eaten, then that’s a direct route into the body,” said Gillian Miller, a co-author and senior scientist with the Michigan-based Ecology Center.