What are PFAS?

You've probably heard about PFAS in the news, but what are they and where do they come from? PFAS, or per- and polyfluoroalkyl substances, are a group of man-made chemicals used in making things like firefighting foam, stain repellants, and non-stick cookware. PFAS can't break down easily in the environment and some PFAS can build-up in our bodies, which can lead to health risks.