Accumulation of volatile PFAS in cloth from indoor air
On this page:
Per- and polyfluoroalkyl substances (PFAS) are a diverse group of several thousand chemicals, many of which are widely used in building materials and consumer products. House dust measurements suggest widespread presence of PFAS in U.S. residences. However, levels of PFAS in indoor air and the fate of PFAS in indoor environments have not been well assessed. As part of the Indoor PFAS Assessment (IPA) Campaign, we deployed suspended clean cloth strips in closets of 10 homes in North Carolina to study partitioning of PFAS from air to cloth. We collected cloth strips at the beginning of the campaign and after 24 hours, 6 days, 1 month and 3 months. Further, we sampled indoor air at the beginning of the campaign and after 3 months. The cloth strips were extracted and analyzed for a range of neutral, volatile PFAS using GC-MS. We observed an accumulation of the fluoroalkyl sulfonamidoethanols MeFOSE and EtFOSE in cloth strips collected from multiple homes. As an example, the accumulation rates for MeFOSE and EtFOSE were 3.3x10-3 ng/(cm² day) and 1.8x10-3 ng/(cm² day), respectively, in one of the studied homes. We also saw an accumulation of 8:2 FTOH and 10:2 FTOH in cloth strips from some homes. Steady state had not been established over the duration of 3 months, but qualitatively, higher concentrations of volatile PFAS found in cloth strips corresponded to higher indoor air concentrations. Additional cloth strips will be collected after 6 and 9 months to further explore PFAS partitioning behavior.