Over 1700 US water systems logged forever chemicals at or above the federal limit, EPA proposes pushing compliance from 2029 to 2031 and rescinding rules for other PFAS

More than 1,700 American public water systems have recorded at least one reading of the 'forever chemicals' PFOA or PFOS at or above four parts per trillion, the federal maximum for each, according to EPA monitoring data mapped by Newsweek. The agency has previously confirmed there is essentially no safe level of exposure to either chemical in drinking water.

The readings come from the EPA's Fifth Unregulated Contaminant Monitoring Rule, which required certain public water systems to test for 29 PFAS compounds between 2023 and 2025; the final dataset was released in August. The International Agency for Research on Cancer classifies PFOA as carcinogenic to humans and PFOS as possibly carcinogenic, and studies link both to liver damage, thyroid disease, high cholesterol and reproductive or developmental harm. Both have been in use since the mid-20th century — in stain-, oil- and water-resistant coatings, food packaging, textiles and firefighting foam — and both resist degradation so thoroughly that contamination from historical materials lingers long after the products were made.

A single reading above the limit is not itself a violation. Compliance is determined by separate compliance monitoring and running annual averages, so the number that names a problem is not the number that triggers one.

The deadlines, meanwhile, are moving. In May the EPA proposed two changes to the Biden-era drinking-water rules: one would rescind the limits covering several other PFAS, the other keeps the PFOA and PFOS limits but lets eligible systems claim up to two additional years, pushing their deadline from 2029 to 2031. Exemptions are available where the delay 'would not result in an unreasonable risk to health.' The public-comment period closed on July 20; the extension has not been finalized.

The agency has also been correcting its own account of the chemicals. Its website long stated that 'the manufacture and import of PFOA has also been phased out in the United States.' In October 2025 the nonprofit Public Employees for Environmental Responsibility filed a complaint under the Information Quality Act challenging that sentence, and in September EPA Assistant Administrator Douglas M. Troutman replied that 'EPA is updating its websites.'

The page now reads: 'Quantities of PFOA may be produced, imported, and used by companies.'