Yes, on PFAS, we are detecting per- and polyfluoroalkyl substances. These are forever chemicals. There are 15,000 of them. We only have the analytical methods to measure 44 of them.
It's a very complex family. It's the old Teflon Scotchgard family of chemicals. The shorter-chain versions are found in airport aqueous firefighting foams and other products. Some are stain repellents and water repellents. They are forever chemicals.
Like plastics, they are found in landfills. They're leaching out of landfills. They're contaminating groundwater supplies. I find them in drinking water supplies in British Columbia.