CA Announces Recommended Notification Level for PFHxS in Drinking Water
The California Office of Environmental Health Hazard Assessment (OEHHA) recommended that the State Water Resources Control Board (Water Board) establish a notification level (NL) for perfluorohexane sulfonic acid (PFHxS) at 2 parts per trillion (PPT), or the lowest level at which it can be reliably detected in drinking water using currently available and appropriate technologies. NLs are nonregulatory, health-based advisory levels that the Water Board establishes as a precautionary measure for contaminants for which regulatory standard have not been set.
PFHxS is a member of the class of chemicals known as per- and polyfluoroalkyl substances (PFAS). OEHHA said that the NL recommendation is based on decreased thyroid hormone levels observed in rats in a National Toxicology Program study (NTP, 2019). OEHHA also noted that there were insufficient data from animal studies on PFHxS to evaluate its potential carcinogenicity.
OEHHA has posted notification levels for a host of other substances in drinking water may be found here.