As Time reports, PFCs have been linked to cancer, thyroid disease and weakened immune systems. Teflon, for example, is a PFOA chemical.
And according to the report, event tiny concentrations are enough to be considered a public health crisis.
"It's remarkable that the richest country on Earth can't guarantee its citizens that their drinking water is completely safe and has no long-term health implications," Bill Walker, managing editor of EWG, said in a statement.
EWG explains that PFCs have been used in the past in hundreds of consumer products, such as cookware, outdoor clothing and food packaging, due to their waterproof and nonstick properties.
But while evidence about the health hazards PFCs pose on people grows, there are still no federal health regulations for the chemicals in drinking water.
Time reports that it's been a quarter of a century since the EPA updated its list of drinking water contaminants in the Safe Drinking Water Act.
Using data from the EPA and publicly documented cases of PFC pollution from places such as manufacturing plants, military airbases and airports, the researchers created an interactive map where people can track contamination sites.
The map will be updated as new contamination sites are uncovered.