Researchers Find High Levels of PFAS Chemicals in Rainwater in United States

Potentially toxic chemicals known as PFAS are known to be widespread in lakes, rivers and groundwater supplies in the United States. Now, researchers have found them in rainwater at potentially harmful levels. If these levels of per- and polyfluoroalkyl substances were found in drinking water, they could trigger regulatory action, according to the Guardian. PFAS are known as "forever chemicals" because they don't degrade in the environment. They're found in food packaging, like pizza boxes, cleaning products, water-repellent fabrics and firefighting foams, according to the Environmental Protection Agency. They're also used in manufacturing facilities. Because they don't degrade, PFAS can build up in the human body and lead to health problems, including effects on the immune system and the thyroid, as well as an elevated risk for certain types of cancer, the EPA said.