The U.S. Environmental Protection Agency on Wednesday released new warnings for synthetic pollutants in drinking water known as "forever chemicals" saying the toxins can still be harmful even at levels so low they are not detectable. The family of toxic chemicals known as per-and polyfluoroalkyl substances, or PFAS, have been used for decades in household products such as non-stick cookware, stain- and water-resistant textiles and in firefighting foam and industrial products.