PFAS Source Attribution: Challenges and Opportunities

During the second half of the twentieth century, per- and polyfluoroalkyl substances (PFAS) were used in a very large number of consumer and industrial products, in a wide range of business sectors. The current legacy of that widespread use is that PFAS compounds of concern are being found almost ubiquitously in the environment. As more sites are investigated for PFAS impacts and the widespread presence of these compounds becomes evident, environmental professionals investigating PFAS impacts are commonly being asked source attribution questions like “is the PFAS in groundwater from the airport or the nearby landfill?” or “how do I know the PFAS in that well came from my plant?”. Over the past few years, some practitioners and researchers have taken stabs at trying to answer these difficult questions, with mixed success. Variability in the chemical compositions of original products, environmental transformation and analytical limitations all present obstacles to defensible source attribution. Drawing on the professional literature and experience from several recent and ongoing PFAS investigations in Michigan, this presentation will explain the challenges associated with source attribution and differentiation of environmental PFAS impacts and present some analytical methods and approaches for potentially overcoming these challenges.