Black and Hispanic communities are disproportionately exposed to “forever chemicals” in their drinking water, according to a first-of-its-kind study from Harvard University that said 18 million Americans are exposed to PFAS levels that exceed limits proposed by the Environmental Protection Agency.

PFAS or, per- and polyfluoroalkyl substances, are known as “forever chemicals” because they do not break down over time and can last indefinitely in the environment. They have been linked to certain types of cancer as well as other illnesses.

The report is the first peer-reviewed study to examine the relationship between PFAS contamination and risk in communities of color. The research also found that location increases the likelihood of PFAS exposure for Black and Hispanic communities, since historic redlining and segregation often situated their neighborhoods near industrial sites, airports, and military facilities.

Read the full article about PFAS in the water supply by Siri Chilukuri at Grist.