But, before you rush out and get a new rain coat, we ask that you take a second to really consider what you purchase. To make rain jackets waterproof, they are often are coated in PFAS (also called PFCs, a pretty not so great group of chemicals like Teflon, often called forever chemicals because of how long they last in the world). While some brands are making waterproof coats without PFAS (thank you @columbia1938, @marmot, and @nauclothing !), many brands still rely on them. So, read our article to find out more and learn some tips for choosing a great coat.