A 2023 U.S. Geological Survey study found that at least 45% of the nation’s tap water is estimated to have one or more types of per- and polyfluoroalkyl substances (PFAS). PFAS are used in various products like non-stick cookware and firefighting foams and are known for their persistence in the environment.

A 2025 study led by McGill University found that nearly one-third of all antibiotics consumed by humans—about 8,500 tons—end up in rivers each year, even after wastewater treatment.