Per and Polyfluoroalkyl Substances in Tap Water Following an Accidental Release of Fire-Fighting Foam into the Drinking Water System in McKeesport, Pennsylvania, USA.

On July 16th, 2021, a fire at an auto body shop in McKeesport, Pennsylvania, caused firefighting foam containing per and polyfluoroalkyl substances (PFAS) to enter the drinking water system. Although the water authority flushed the distribution system, community concerns persisted about PFAS residues in plumbing and contamination risk at consumers' taps. To address this, we collected tap water from kitchen, bathroom, and laundry sinks in homes during November 2021- May 2023. Point-of-use filters (POUFs) were provided, and filters were collected to evaluate their efficacy. Our results showed that five months after the incident, perfluorooctanesulfonate (PFOS) levels in 5 out of 15 homes exceeded the USEPA's drinking water threshold of 4 ppt. 6:2 fluorotelomer sulfonate was frequently detected in the tap water. Kitchen taps had the highest PFAS levels, followed by bathroom and laundry taps. GenX was detected in aerator extracts from 5 homes but determining its source requires further investigation. POUFs effectively removed specific PFAS, and hydrant flushing by the local water authority was successful in decreasing levels across the water system. However, lack of clear communication following the event left the community distrustful of their water quality, and community members reported feeling disconnected from the decision-making process.