Human Interest Human Interest News Cancer-Causing 'Forever Chemicals' Found in Nearly Half of U.S. Tap Water, Study Finds The U.S. Geological Survey found that at least 45% of tap water in the U.S. is estimated to have one or more types of PFAS, known as "forever chemicals," which are linked to serious health issues By Vanessa Etienne Vanessa Etienne Vanessa Etienne is an Emerging Content Writer-Reporter for PEOPLE. People Editorial Guidelines Published on July 7, 2023 10:50AM EDT Woman's hand filling a glass of tap water from a kitchen sink. Photo: Getty Images Nearly half of the country’s tap water could be contaminated with cancer-causing “forever chemicals,” according to a new study. The study — released Wednesday by the U.S. Geological Survey — found that at least 45% of tap water in the United States is estimated to have one or more types of per-and poly-fluoroalkyl substances. The United States Environmental Protection Agency (EPA) states that PFAS, or per-and poly-fluoroalkyl substances, are a group of about 14,000 man-made chemicals that are "very persistent in the environment and in the human body – meaning they don't break down and they can accumulate over time." PFAS, also known as "forever chemicals" by the NIH, can last for years without breaking down and are linked to cancer, fetal complications, liver disease, kidney disease, thyroid disease, fertility problems, autoimmune disorders and other serious health issues. The USGS said the study is the first to test for PFAS in tap water from both private and public water supplies, testing 716 locations across the country between 2016 and 2021. Of the locations, both rural and urban areas, 447 rely on public water supplies and 269 rely on private wells. RELATED: 3M Agrees to Pay $10.3B in Settlement of Lawsuits Claiming 'Forever Chemicals' Contaminate Drinking Water Woman's hand filling a glass of tap water from a kitchen sink. Getty Images RELATED: Cancer-Causing 'Forever Chemicals' Found in Many Kinds of Contact Lenses, Study Finds Scientists estimate that there is about a 75% chance of PFAS being found in rural areas and about a 25% chance in urban areas. High exposure areas were reported in the Great Plains, Great Lakes, Eastern Seaboard, and Central/Southern California regions. "USGS scientists tested water collected directly from people’s kitchen sinks across the nation, providing the most comprehensive study to date on PFAS in tap water from both private wells and public supplies,” said USGS research hydrologist Kelly Smalling, the study’s lead author. “The study estimates that at least one type of PFAS – of those that were monitored – could be present in nearly half of the tap water in the U.S. Furthermore, PFAS concentrations were similar between public supplies and private wells.” The EPA regulates public water supplies while private water supplies are maintained, tested and treated by homeowners. Anyone interested in testing and treating private wells should contact their local and state officials for guidance as testing is the only way to confirm the presence of PFAS in wells. "If the average American is worried about the quality of their drinking water, they can use this and other studies to get informed, evaluate their own [personal] risk and reach out to their local health officials about testing or treatment," Smalling told NPR.