CNN  — 

Potentially toxic chemicals are in the drinking water supplies of several major metropolitan areas in the US, including Miami, New Orleans and Washington, DC, according to a new report from the Environmental Working Group (EWG).

The findings, published by the environmental advocacy group this week, suggested that PFAS, manmade chemicals that are extremely persistent in the environment and in human bodies, could be found in major water supplies in the US.

The group tested the drinking water at 44 sites in 31 states and Washington for PFAS chemicals.

Of the areas tested, only Meridian, Mississippi, had no detectable levels of the toxic chemicals. The community draws its drinking water from wells more than 700 feet deep, the group said.

The water supplies in Brunswick County, North Carolina, and Quad Cities, Iowa, contained the highest levels of the chemicals, more than 100 times the EWG’s suggested limit. The advocacy group’s recommended PFAS limit is 1 part per trillion in drinking water, about 70 times stronger than federal recommendations.

The potential harm of PFAS

PFAS is short for perfloroalky and polyfuoroalkyl substances which include chemicals known as PFOS, PFOA and GenX. The report refers to them as “forever chemicals” because they don’t break down once they’re in the environment.

They’ve been manufactured since the 1940s for their ability to repel oil and water. They’re found now in nonstick products, paints, cleaning products and food packaging.

A growing body of research of PFAS’ impact on human health shows exposure is linked to reproductive and developmental harm as well as liver and kidney damage and cancer, according to the Environmental Protection Agency.

Agencies disagree on PFAS limits

In 2016, the EPA released a non-enforceable lifetime health advisory for PFOA and PFOS at 0.07 parts per billion in drinking water, or 70 parts per trillion.

In 2018, the Agency for Toxic Substances and Disease Registry, a division of the US Department of Health and Human Services, indicated that the “minimal risk levels” for oral exposure to PFOS and PFOA should be seven to 10 times lower than what the EPA currently suggests.

The only cities that fell within the EWG’s 1 part per trillion PFAS limit were Seattle, Memphis and Tuscaloosa, Alabama, according to the report.

More than half of the sites tested in the Environmental Working Group report exceeded its suggested levels.