PFOA is in 20% of US water supplies, a reanalysis of 2013 data finds -- Quartz

PFOA is not currently regulated by the EPA, so state or local governments aren’t required to test for them. The EPA does set a recommended maximum exposure level for PFOA at 70 parts per trillion. But it’s nonbinding: states can choose to comply or not. In New Jersey, the local environment department has set the “acceptable” level at 14 ppt, the most stringent in the country (there is a lot of PFOA in New Jersey’s drinking water—the Environmental Working Group calculated the EPA’s testing method would have missed 75% of the contamination in that state).