LAPEER, Mich. (AP) – Experts are raising concerns that sewage sludge used as fertilizer around the U.S. could contaminate crops with potentially harmful chemicals.
About half of the 7 million tons of sludge generated each year is applied to farm fields and other lands. It’s a high-quality, low-cost soil additive.
But some contains chemicals known as PFAS. Studies show they can be absorbed into crops such as lettuce and tomatoes.
Scientists say the extent of any threat to food supplies is unknown because little testing has been done.
The federal government hasn’t limited PFAS in fertilizer or developed a standard for determining safe levels.
A dairy farm in Maine that used sludge shut down after high PFAS levels were found in its milk. Cities in Michigan and Wisconsin have stopped providing sludge to local farms.
