More than 1 in 5 Americans use PFAS chemicals in their water

[New Sancai Compilation and First Release] A new study shows that more than 20% of people in the United States may have drinking water contaminated by "permanent chemicals."

The U.S. Geological Survey (USGS) estimates in the October 24, 2024 issue of Science Advances that 75 to 95 million Americans rely on groundwater containing detectable concentrations of chemicals known as PFAS ( Perfluoroalkyl substances and polyfluoroalkyl substances).

"The results of this study indicate widespread PFAS contamination in groundwater used by public and private drinking water supplies in the United States," said lead researcher Andrea Tokranov, a research hydrologist with the U.S. Geological Survey.

Based on its research, the USGS has created an interactive online map that people can use to examine the potential for groundwater in their area to be contaminated with PFAS.

"This new predictive model can help prioritize areas for future sampling to help ensure that people don't unknowingly drink contaminated water," Tokranov said. "This is especially important for private well users, who may not have access to water quality information in their area and may not have the same access to testing and treatment as public water providers."

For the study, researchers tested more than 1,200 groundwater samples collected by U.S. Geological Survey scientists to determine the presence of 24 common types of PFAS.

The results showed that the most commonly detected compounds were perfluorobutane sulfonate (PFBS), perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA).

"Based on this information, a detailed machine learning model was developed and used to identify which geographic areas were more likely to be contaminated," Tokranov said. "This information is consistent with existing USGS data on specific areas' dependence on groundwater for access. Drinking water population studies.

Researchers say Florida and California are states where most people rely on public water supplies from groundwater sources that may be contaminated.

The results show that Michigan, Florida, North Carolina, Pennsylvania, New York and Ohio have the highest number of people whose private wells may be contaminated by PFAS.

The study also includes population estimates of PFAS exposure in groundwater in each state. For example, 86% to 98% of residents in Massachusetts who use public water supplies may be exposed to PFAS from contaminated groundwater, while 67% to 87% of residents in Connecticut who use private wells may have their drinking water contaminated by PFAS.

PFAS are called "forever chemicals" because they combine carbon and fluorine molecules, one of the strongest chemical bonds. This makes the removal and breakdown of PFAS very difficult.

Researchers say PFAS compounds have been used in consumer products since the 1940s, including firefighting foam, nonstick pans and food wrappers. These chemicals are also widely used in industrial processes.

Health problems associated with PFAS include reduced immune response to vaccinations, impaired liver function, reduced birth weight, and increased risk of certain diseases, cancer, and more.

The researchers noted that the U.S. Environmental Protection Agency has set maximum contamination levels for six PFAS in drinking water.

(Compiled by: Wang Jimin)

(Editor: Jiang Qiming)

(Source of the article: Compiled and published by New Sancai)