Results Underscore that PFAS Was Not Transported by Air Beyond the FTC
As reported to WDNR today, soil samples collected in September and October on the perimeter of the Tyco Fire Technology Center (FTC) contained less PFOS and PFOA than soil found in typical urban areas. In fact, these perimeter soil samples are very similar to samples of soil taken from areas in North America like Vermont where there are no known local sources of PFAS. These measurements underscore that PFOA and PFOS are found everywhere in the United States and further demonstrate that PFAS compounds are not being transported by air beyond the FTC.
Additionally, Tyco also tested approximately 30 shallow soil samples immediately around the outdoor fire training area and test houses at the FTC. PFAS concentrations in these samples were also low, and they declined as the sampling moved away from locations where our foam was historically tested. Thus, given that aerial transport of PFAS was insignificant even very close to the fire training area, this provides further evidence that aerial transport did not occur outside of Tyco’s property.
Table 1. Median values of PFOS and PFOA concentrations in soil samples (micrograms per kilogram or parts per billion)reported in published literature and along the Tyco FTC perimeter.
Compound | Pristine North America Soils1 | Global Urban Soils2 | Statewide Survey of Vermont Soils3 | FTC Perimeter Soil Collected Fall 2020 |
PFOS | 0.39 | 1.88 | 0.40 | 0.29 |
PFOA | 0.54 | 2.42 | 0.68 | 0.68 |
1Rankin, K., Mabury, S.A., Jenkins, T.M. and Washington, J.W., 2016. A North American and global survey of perfluoroalkyl substances in surface soils: Distribution patterns and mode of occurrence. Chemosphere, 161, pp.333-341.
2Strynar, Mark J., Andrew B. Lindstrom, Shoji F. Nakayama, Peter P. Egeghy, and Laurence J. Helfant. “Pilot scale application of a method for the analysis of perfluorinated compounds in surface soils.” Chemosphere 86, no. 3 (2012): 252-257.
3Zhu, W., Roakes, H., Zemba, S., Badireddy, A. “PFAS Background in Vermont Shallow Soils.” 2019.