TRAVERSE CITY, Mich. (AP) — Drinking water from nearly half of U.S. faucets likely contains “everlasting chemicals” that can cause cancer and other health problems, according to a government study released Wednesday.
Man-made compounds known collectively as PFAS contaminate drinking water to varying degrees in cities and towns — and in private wells and public systems, the US Geological Survey said.
The researchers described the study as the first national effort to test PFAS in tap water from private sources in addition to regulated sources. It builds on previous scientific findings that the chemicals are widespread, appearing in consumer products as diverse as nonstick cookware, food wrappers and water-resistant clothing and making their way into food supplies. ‘water.
Because the USGS is a scientific research agency, the report makes no policy recommendations. But the information “can be used to assess the risk of exposure and inform decisions about whether or not you want to treat your drinking water, have it tested, or get more information from your state” about the local situation, a said lead author Kelly Smalling, a research hydrologist.
The U.S. Environmental Protection Agency in March proposed the first federal drinking water limits on six forms of PFAS, or perfluorinated and polyfluorinated substances, which remain in the human body for years and do not degrade in the environment. A final decision is expected later this year or in 2024.
But the government has not banned companies using the chemicals from dumping them into public sewage systems, said Scott Faber, senior vice president of the Environmental Working Group, an advocacy organization.
“We should deal with this problem where it starts, instead of putting a red light after the accident,” he said. “We should require polluters to treat their own waste.”
Studies in lab animals have found potential links between PFAS chemicals and certain cancers, including the kidneys and testicles, as well as problems such as high blood pressure and low birth weight.
Federal and state programs typically measure exposure to pollutants such as PFAS at water treatment plants or the groundwater wells that supply them, Smalling said. By contrast, the USGS report was based on samples from taps at 716 locations, including 447 that rely on public supply and 269 that use private wells.
The samples were taken between 2016 and 2021 from a range of locations – mostly residences but also a few schools and offices. They included protected lands such as national parks; residential and rural areas without identified sources of PFAS; and urban centers with industrial or waste sites known to generate PFAS.
Most notches were sampled only once. Three were sampled multiple times over a three-month period, with results changing little, Smalling said.
The scientists tested 32 PFAS compounds – most of those detectable by available methods. Thousands more are believed to exist but cannot be spotted with current technology, Smalling said.
The types most often found were PFBS, PFHxS and PFOA. PFOS, one of the most prevalent nationwide, also made frequent appearances.
Positive samples contained up to nine varieties, although most were closer to two. The median concentration was around seven parts per trillion for the 32 types of PFAS, although for PFOA and PFOS it was around four parts per trillion – the EPA’s proposed limit for these two compounds.
The heaviest exposures occurred in cities and near potential sources of compounds, particularly on the east coast; Great Lakes and Great Plains urban centers; and central and southern California. Many tests, mostly in rural areas, found no PFAS.
Based on the data, the researchers estimated that at least one form of PFAS could be found in about 45% of tap water samples nationwide.
The study points out that users of private wells should have their water tested for PFAS and consider installing filters, Faber of the environmental task force said. Filters containing activated carbon or reverse osmosis membranes can remove the compounds.
The USGS study is “further evidence that PFAS is incredibly prevalent and that people who rely on private wells are especially vulnerable to harm from these chemicals,” Faber said.
———
The Associated Press’s climate and environmental coverage receives support from several private foundations. Learn more about AP’s climate initiative here. The AP is solely responsible for all content.