• Posted May 16, 2023

Black, Hispanic Americans More Likely to Have PFAS Chemicals in Drinking Water

Black and Hispanic communities in the United States are more often poor -- and also more likely to have harmful levels of per- and polyfluoroalkyl substances (PFAS) in their drinking water, a new study reveals.

Sources of PFAS pollution -- including major manufacturers, airports, military bases, wastewater treatment plants and landfills -- are disproportionately sited near watersheds that serve these poorer communities, Harvard researchers found.

"Our work suggests that the sociodemographic groups that are often stressed by other factors -- including marginalization, racism and poverty -- are also more highly exposed to PFAS in drinking water,"said study co-author Jahred Liddie. He is a PhD student in population health sciences at Harvard T.H. Chan School of Public Health, in Boston.

"Environmental justice is a major emphasis of the current administration, and this work shows it should be considered in the upcoming regulations for PFAS in drinking water," Liddie said in a school news release.

The U.S. Environmental Protection Agency (EPA) has proposed a first-ever national drinking water regulation for six PFAS, expected to be finalized by late 2023. That regulation would establish maximum contaminant levels of two PFAS compounds -- PFOA and PFOS -- at 4 parts per trillion (4 ng/L). It would also limit the other four.

PFAS are widely used because they have stain-resistant and water-resistant properties. But they have extreme persistence in the environment. Exposure to these so-called "forever chemicals" is linked to diabetes, heart disease and cancer.

For this new study, the researchers used PFAS monitoring data from nearly 7,900 U.S. community water systems in 18 states: California, Colorado, Illinois, Indiana, Kentucky, Maine, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, South Carolina, Utah, Vermont and Wisconsin.

The investigators analyzed more than 44,000 samples collected from 2016 to mid-2022. The researchers also looked at the geographic locations of PFAS sources from multiple databases.

PFAS detection in a water system was associated with the number of sources nearby and proportion of people of color, the study authors said.

For each additional industrial facility, military fire training area and airport in a community water system's watershed, there was a 10% to 108% increase of perfluorooctanoic acid, and a 20% to 34% increase in perfluorooctane sulfonic acid in drinking water, the study found.

About 25% of the people in the areas studied were served by community water systems that had levels of PFAS above 5 ng/L. If the EPA's new proposed level of 4 ng/L is implemented, that means more than 25% of Americans could be exposed to what are then considered to be dangerous levels of PFAS.

"Our findings are particularly concerning because past work on environmental disparities for other pollutants shows marginalized populations are susceptible to greater risks of adverse health outcomes compared to other populations, even at the same exposure levels,"said study co-author Elsie Sunderland. She is a professor of environmental chemistry and of earth and planetary sciences at the Harvard School of Engineering and Applied Sciences.

"Regulating releases from PFAS sources and ensuring that people have safe drinking water is especially important in the most vulnerable communities to protect public health,"Sunderland added.

Public comment on the EPA proposal ends May 30.

The study findings were published May 15 in Environmental Science & Technology. This research was supported by the U.S. National Institute of Environmental Health Sciences.

More information

The U.S. Centers for Disease Control and Prevention has more on PFAS.

SOURCE: Harvard T.H. Chan School of Public Health, news release, May 15, 2023