Of the half-dozen coats hanging in my closet, all but one are made for trudging around in the outdoors. Each of these jackets has an invisible coating of poly- and perfluoroalkyl substances that makes them waterproof. If your closet is similar, your jackets have similar coatings, as the outdoor apparel industry has relied on these chemicals for decades. While a jacket that keeps you dry during a rainy hike is of course desirable, PFASs have a big problem. The highly fluorinated chemicals find their way into the ecosystem through manufacturing waste, and they are shed as the coatings erode off of garments. Studies have linked exposure to PFASs to liver and immune system damage, neurological damage, and some cancers, among other ailments. Manufacturers that make goods like furniture, carpets, and cookware have found ways to stop using PFASs, but the outdoor apparel industry has been slower to change. Read more at Wired.