Chapter 2: Why PFASs Are Chemicals of Concern

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) constitute a large and diverse class of organic chemicals containing fully fluorinated carbon atoms that impart these substances with extraordinary persistence. Here we summarize health and environmental hazards associated with PFASs and review U.S. and international regulatory initiatives undertaken to address the presence of PFASs in consumer products. Certain data-rich PFASs, such as perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), are persistent, mobile, bioaccumulative, and environmentally ubiquitous, and strong evidence suggests they are associated with adverse human health effects and ecological damage. Less is known about the hazard traits of many other PFASs, but nearly all are considered environmentally persistent. Government initiatives to address PFASs are increasing, but the current regulatory landscape is uneven, complex, and rapidly evolving. However, there is a general trend toward a more precautionary approach that encourages industries to seek safer alternatives.