Source identification and distribution of per- and polyfluoroalkyl substances (PFAS) in the freshwater environment of USA

A family of anthropogenic organic pollutants with a long history of use, per- and polyfluoroalkyl substances (PFAS) are present in a wide range of environmental compartments, including drinking water, soil, biota, surface water, and groundwater. As a result of their persistent nature in the environment, PFAS have been found in several species of wildlife worldwide, such as invertebrates, aquatic organisms, amphibian species, aquatic plants, alligator, seabird, mammal tissues, as well as in human body. This review provides an in-depth assessment of the distribution of commonly detected PFAS in surface water within five distinct regions of the United States. Furthermore, the research aims to identify the key sources that contribute to the presence of PFAS and pinpoint data gaps in specific states, emphasizing the need for further research. The Southeastern region, particularly the states of Florida, South Carolina, North Carolina, and Virginia, has been observed to show a higher degree of PFAS contamination. The states of California, Colorado, Nevada, and Montana in the Western region, as well as Maryland, New Jersey, New York, and New Hampshire in the Northeast region also showed a higher presence of PFAS. In the Southwest region, we identified a significant lack of data, while in the Midwest, with the exception of Michigan, we observed a comparatively lower amount of PFAS in surface water. It is expected that including more PFAS in addition to the few commonly studied will increase the total concentration of PFAS, which aids in understanding the actual degree of PFAS pollution. The synthesis of fluoropolymers and the incorporation of PFAS in the manufacturing and production of consumer goods, together with the utilization of fluorinated AFFF, have been recognized as notable sources of PFAS. Possible strategies to decrease and eliminate PFAS from the US are discussed as well.