PFAS, or per- and polyfluoroalkyl substances, are a group of human-made chemicals that have been in use since the 1940s. There are approximately 5,000 types of PFAS, some of the most common being perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). These chemicals are used in a wide range of consumer products that people use daily such as cookware, pizza boxes and stain repellants, due to their resistance to heat, water and oil. They are also used in industrial applications and in the production of some firefighting foams.One of the major concerns with PFAS is their persistence in the environment and in the human body – meaning they don’t break down, and they can accumulate over time, leading to potential negative health effects. Studies indicate that exposure to PFAS can lead to adverse health outcomes in humans, including reproductive and developmental, liver and kidney and immunological effects, among others. The impact and regulation of PFAS is ongoing, with multiple regulatory studies and laws already in place or underway.