They’re in stain resistant carpets and clothing, cookware, some cosmetics, outdoor gear, and even dental floss. You may know them as Teflon®, or Scotchguard®. You have them in your body and they’ve been detected in 455 California drinking water sources thus far. I’m talking about a class of fluorinated chemicals, called PFAS, and they threaten California’s water and its people. Why haven’t we done more about them?