Decades of firefighting foam use at former military sites in Bucks and Montgomery counties have left a toxic legacy of PFAS contamination that continues to affect residents’ health and drinking water, according to a study.
The foam, known as aqueous film-forming foam (AFFF), was used extensively at military installations including the Naval Air Station Willow Grove, the Horsham Air Guard Station, and Naval Air Warfare Center Warminster.
These sites are now known sources of widespread groundwater contamination. Private wells near the bases have shown PFAS concentrations thousands of times higher than the Environmental Protection Agency’s (EPA) new safety threshold of 4 parts per trillion (ppt). In some cases, levels of PFOS, one of the most harmful PFAS compounds, were measured at nearly 5,000 ppt.
According to the article, a recent national study led by the Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease Registry (ATSDR) revealed troubling health implications for the affected communities. Blood tests conducted on residents living near contaminated wells showed that nearly 100% had elevated PFAS levels in their systems. Alarmingly, about 30% of those tested had levels high enough to warrant medical monitoring under federal health guidance. Exposure to PFAS has been linked to a variety of serious health issues, including elevated cholesterol, thyroid dysfunction, pregnancy complications, liver problems, metabolic disruptions, and certain types of cancer. These health risks have triggered growing concern and calls for long-term monitoring.
The issue extends beyond private wells. Local water utilities such as Aqua Pennsylvania have recently taken public wells offline in Upper Dublin and North Hills due to PFAS contamination, even though some levels were below the EPA’s former advisory limit of 70 ppt. Experts argue that the older standard significantly underestimated the risks, and newer research suggests safe thresholds are far lower. Worryingly, PFAS contamination is no longer limited to areas immediately surrounding military bases. It has now spread across multiple regional water systems, raising broader concerns about public water safety in southeastern Pennsylvania.
In response, government and community actions are accelerating. Bucks and Montgomery counties were awarded $5 million in federal funding to support long-term health studies for impacted residents. At the state level, lawmakers are advancing House Bill 1261, which would ban the use, sale, and manufacture of firefighting foam containing PFAS in Pennsylvania. The bill also includes funding for safer firefighter training and proper disposal of the hazardous material. Legal action has also been taken: Bucks County has sued major chemical manufacturers, including 3M and DuPont, for damages under both state and federal laws.