The latest research reveals alarming levels of contamination in northeastern Tennessee waterways, by the chemicals known as per- and polyfluoroalkyl substances or PFAS. Many communities and ecosystems are exposed to PFAS in soil, surface water, groundwater and air. Dan Firth, chair of the solid waste and mining committee for the Tennessee chapter of the Sierra Club, said they collected 20 water samples from lakes and rivers around Kingsport and Johnson City, and about 60% tested positive for the substances, often known as "forever chemicals" because they do not degrade over time. ...