In their daily job of protecting lives, firefighters are exposed to a lot of hazards — not just smoke and fire, but unsafe traffic, violence and vicious cats in trees. However, one of the most perilous risks in firefighting can be somewhat invisible: so-called "forever chemicals," the substances that are used to suppress fires, such as in fire extinguishers and foams dumped on wildfires.
One common class of forever chemicals are PFAS, which stands for per- and polyfluoroalkyl substances, and they are compounds made of chlorine and fluorine nicknamed "forever chemicals" because they essentially never break down.
