Abstract View
Sampling of Per- and Polyfluoroalkyl Substances (PFAS) with Residential Air Filters
CLARA EICHLER, Naomi Chang, Jiaqi Zhou, Glenn Morrison, Jason Surratt, Barbara Turpin, UNC-Chapel Hill
Abstract Number: 238
Working Group: Indoor Aerosols
Abstract
Per- and polyfluoroalkyl substances (PFAS) are a diverse group of chemicals that includes over 9,000 different compounds. Because of their water- and stain-resistant and non-stick properties, PFAS are widely used in consumer products. Not surprisingly, PFAS have been found in indoor air and dust, and concentrations tend to be higher indoors than outdoors. However, the fate of PFAS in indoor environments has not been well assessed. The objective of this preliminary study was to evaluate if filters for residential heating and air conditioning (HAC) systems can be used to sample suspended particles that may contain PFAS. We deployed 6 HAC filters total in 5 single-family homes in North Carolina for 4-9 weeks, extracted the filter material, and analyzed the extracts for nine volatile PFAS using GC-MS. The HAC filter extracts were also analyzed for 34 legacy and emerging per- and polyfluoroalkyl acids (PFAAs) with an AB Sciex Triple Quad UPLC-MS/MS, and for ionic composition using a Dionex ICS-3000 and Aquion.
We found at least one volatile PFAS compound in 5 of the 6 filters. 6 out of 9 analytes were measured above their quantification limits, i.e., the fluoroalkyl sulfonamidoethanols MeFOSE and EtFOSE, the fluoroalkyl sulfonamide MeFOSA, and three fluorotelomer alcohols. The filters showed different analyte profiles for each home. One filter had been deployed for almost 9 weeks, and higher concentrations and a higher number of analytes were observed. Similar trends were observed for the PFAAs. Overall, this sampling strategy proved to be useful, but additional refinements are necessary. Over the summer, we will deploy HAC filters in additional homes for at least 8 weeks as part of a field campaign to assess PFAS partitioning and fate in indoor environments.