when the sludge contains 4 to 5 ppb (4000-5000 ppt) of PFOS or 1 ppb (1000 ppt) PFOA. According to EPA, 1 ppb is on the low end of typical US sludge concentrations. The assessment only covers ...

The 75 ppb level was set in 2008 and the agency is supposed to reevaluate this limit every five years and EPA administrator Gina McCarthy said in a statement that a lower level will bring the ...

Michigan's drinking water systems face challenges as lead levels exceed new standards as Congress debates repealing Biden's ...