Reanalysis of PFO5DoA Levels in Blood from Wilmington, North Carolina, Residents, 2017-2018
By Nadine Kotlarz, James McCord, Nate Wiecha, Rebecca A Weed, Michael Cuffney, Jeffrey R Enders, Mark Strynar, Detlef R U Knappe, Brian J Reich, and Jane A Hoppin
Environ Health Perspect
February 2, 2024
DOI: 10.1289/EHP13339
Per- and polyfluoroalkyl substances (PFAS) are a large class of synthetic, fluorinated chemicals.1 Wastewater discharges from a fluorochemical manufacturing facility (“Fayetteville Works”) contaminated the lower Cape Fear River in North Carolina with per- and polyfluoroalkyl ether acids (PFEAs),2 a subgroup of PFAS. The GenX Exposure Study aims to characterize exposure to PFAS in Cape Fear River Basin, North Carolina, residents. The study started in 2017 with Wilmington, North Carolina, residents who were exposed to PFEAs through municipal water derived from the lower Cape Fear River.3,4
In some Wilmington serum samples, we identified 2,2,3,3-tetrafluoro-3-((1,1,1,2,3,3-hexafluoro-3-(1,2,2,2-tetrafluoroethoxy)propan-2-yl)oxy)propanoic acid (also known as Hydro-EVE, DTXSID60904459), a polyfluoroalkyl ether carboxylic acid generated at Fayetteville Works. This chemical was first identified in 2017 in the Cape Fear River downstream of Fayetteville Works.5 We could not quantify the concentrations of Hydro-EVE in Wilmington serum samples by accurate mass measurements because we were unable to resolve this compound from isobaric 6:2 fluorotelomer sulfonic acid [(6:2 FTS, DTXSID6067331) (5.15ppm mass difference for the molecular ions [M-H]−)], which we also observed in some serum samples.4 6:2 FTS is a component of some aqueous film-forming foam formulations6 and has been found in human serum samples in the United States.7 Because of our method’s inability to distinguish Hydro-EVE from 6:2 FTS, we did not report concentrations for either compound in our previous report.4
Our original analysis of PFEAs in Wilmington serum samples was conducted by liquid chromatography coupled to high-resolution mass spectrometry.4 At that time, authentic analytical standards for most PFEAs detected in the Cape Fear River were not commercially available. However, in 2022, we acquired authentic analytical standards for Hydro-EVE and 6:2 FTS and obtained measurements for a subset of GenX Exposure Study participants. This letter reports the results of the measurements for Hydro-EVE and 6:2 FTS in blood serum samples from Wilmington residents from 2017 and 2018.
Location:
Topics: