Virtually every living thing on Earth, from Patagonian penguins to newborn human babies, has been touched by the synthetic chemicals known as per- and polyfluoroalkyl substances, or PFAS. In fact, you would be hard pressed to find a sample of human blood, tissue or breast milk without detectable levels of at least one type of PFAS. Making matters worse, researchers are continually uncovering links between human exposure to PFAS and poor health outcomes, including a weakened immune system, a heig