Analysis - Every week seems to bring a new report about where "forever chemicals" have been found: in soil, drinking water, our bodies and marine animals. Their proper scientific name is perfluoroalkyl and polyfluoroalkyl substances (PFAS). But they're more commonly called "forever chemicals" because, once they're in an environment, they almost never break down. These chemicals are harmful in many ways: they kill fish, disrupt plant growth and can make humans very ill.