PFOA in drinking water

0.004 ppt (parts per trillion) is the new limit for PFOA in US drinking water.

By the way, PFOA belong to the group of PFAS, so called “forever chemicals” which do not degrade well. Compared to 2012 in West Virginia, this new maximum value is 37.5 million times lower.

Source: https://de.wikipedia.org/wiki/Per-_und_polyfluorierte_Alkylverbindungen