It wasn't immediately clear what sewage sludge was doing on farm fields. It turns out this has been standard practice for many years: > In March, the state ann

It wasn't immediately clear what sewage sludge was doing on farm fields. It turns out this has been standard practice for many years: > In March, the state announced that it would temporarily halt the land application of sludge and begin the testing, after milk from a dairy farm in Arundel, Maine, was found to be contaminated with PFAS that had likely come from sludge that the farmers had spread on their land as fertilizer. ... From the linked announcement: > The practice of spreading sludge as a soil amendment has been a common practice in Maine and across the nation for decades. Land application of sludge material occurred long before there was knowledge that it may contain PFAS or the health implications of PFAS. https://www.maine.gov/dep/news/news.html?id=1186570 https://www.maine.gov/dep/news/news.html?id=1186570 The problem appears to be the extreme chemical stability of PFAS and related perfluoroalkyl derivatives. They'll survive biological degradation, high temperatures, and light treatments that would chew up most other molecules. It seems unlikely that Maine will be an isolated case.