Perfluorooctanoic acid (PFOA) is a member of a class of chemicals called perfluoroalkyl acids (PFAAs), which are industrial chemicals that are used to make everyday products including surfactants and surface protectors in carpets, leather, paper, food containers, fabric, upholstery, fire-fighting foam, and floor polishes. With a half-life of about 4 years in humans and a very high thermal and chemical stability, PFOA is very persistent in the environment. In addition, PFOAs have been reported to cause diverse toxic effects in laboratory animal and primates, as well as increase the risk of prostate cancer mortality.
My hometown, Hoosick Falls, New York, recently discovered very high concentrations of PFOA and other PFAA related chemicals in their local water source. The EPA reported values over 400 parts per trillion in Hoosick Falls, which is well over the established health advisory level of 70 parts per trillion. While residents have been protected from further contamination through the installation of filtration systems, little is known about how PFOA and other PFAAs are moving in the aquifer. NY State Department of Environmental Conservation (DEC) data show a large spatial variation in the PFOA concentrations in Hoosick Falls wells, with neighboring houses showing some large differences. However, this spatial variation is at this moment only based on single point measurements.
The purpose of this project is to study the temporal and spatial variation of PFOA in the water of three different private wells, as well as to study the spatial variation of PFOA in streams throughout the Hoosick area. Preliminary results from two wells located close together show large differences in PFOA levels. This is consistent with DEC data and illustrates the unpredictability in spatial variation. Samples from streams in the Hoosick area also show considerable spatial variability. Although little temporal variation was observed between summer and fall, samples collected in the winter revealed much higher PFOA, but much lower PFOS. These data should be considered preliminary and possible causes for the observed changes will be discussed.