The initiation of a new water quality test requirement for drinking water has resulted in the closure of four major drinking-water wells, and could lead to delays in the redevelopment of the former Willow Grove Naval Air Base due to water contamination issues.
Perfluorooctane sulfonate (PFOS) is a chemical that was routinely added to foams used for firefighting at former Naval Air bases at both Willow Grove and Warminster, both of which have been inactive for many years. Production of the chemical was phased out in the US about ten years ago, and until recently local water agencies have not been required to screen drinking water for the presence of these compounds.
Now, local residents are concerned that their private wells may also be contaminated with PFOS, some believing that the recent surge in cancer cases in their area over the last couple of years, including leukemia, lymphoma, breast-, liver- and pancreatic cancer, can be attributed to their local water supply being contaminated with this chemical pollutant.
The resident's fears may be well founded. Studies conducted on animals have found that exposure to PFOS can cause problems with reproduction and development, and is also associated with an increased risk of cancer.
One resident who worked at the Warminster Navy Base in the 1950s is not surprised that the water is contaminated, as back in the day everything got disposed of underground.
According to Karen Johnson, an EPA spokesperson, authorities have been aware of PFOS for some time, but until recently have not had the necessary lab equipment to test for the compound.
In Warminster, recent tests have revealed that PFOS levels are three times higher than the recommended threshold in one drinking-water well, which was shut down together with a nearby well where levels just below the recommended threshold were recorded. In Horsham, two wells were shut down in August after tests revealed PFOS levels three times higher than the safety threshold at one well, and five times higher at another. The affected towns now need to import drinking-water from nearby towns to meet their needs.
According to Tina O'Rourke, a representative of the Horsham water authority, these two wells supplied roughly 26% of the town's water, and estimated that it would take at least another year to resolve the situation, either by finding an alternative source of supply or by treating the contaminated water within the two wells.
Perfluorooctane Sulfonate Contamination
Perfluorooctane sulfonate is a common type of perfluorinated compound that was developed in the early 1950s and is commonly used in a variety of products, including fire-fighting foam, semi-conductors, non-stick coatings, textiles, and paper-based products. While it is no longer produced in the US, it is still abundant in the environment. The reason for this is that because the compound was developed to be resistant to water and fats, it does not readily break down in the environment. Their slippery consistency makes them difficult to screen, difficult to eradicate, and allows them to spread easily. Consequently they are abundant in the environment and have been found in the tissue of fish and other animals, including humans across the US.
Research conducted on primates and rodents have shown that PFOS compounds accumulate in the kidneys and liver, and is associated with reproductive and developmental problems, as well as cancer. A provisional health advisory put out by the EPA in 2009 states that exposure to PFOS levels over 0.2 ppb "may cause adverse health effects in the short term (weeks to months)."