What is PFAS Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals. PFAS have been manufactured and used in a variety of industries around the globe, including in the United States since the 1940s. PFOA and PFOS have been the most extensively produced and studied of these chemicals. PFAS, are a family of approximately 5,000 – 10,000 man-made organic chemicals. PFAS are used in our everyday used commodities such as non-stick cookware like pans, fabric stain-protective coatings, fast food wrappers, microwave popcorn bags, personal care products, and firefighting foams. The carbon-fluorine bonds of PFAS means these are resistant to degradation in the environment; can persist for decades in water and air; and accumulate in our bodies over time.