Indoor air concentrations of PM<sub>2.5</sub> quartz fiber filter-collected ionic PFAS and emissions to outdoor air: findings from the IPA campaign
Naomi Y. Chang, Clara M. A. Eichler, Daniel E. Amparo, Jiaqi Zhou, Karsten Baumann, Elaine A. Cohen Hubal, Jason D. Surratt, Glenn Morrison, Barbara J. Turpin
Abstract
; DF = 67%) were highest indoors. Residential indoor air concentrations (sum of measured PFAS) were, on average, 3.4 times higher than residential outdoor air concentrations, and an order of magnitude higher than regional background concentrations. Indoor-to-outdoor emission rate estimates suggest that emissions from single unit homes could be a meaningful contributor to PFBA, PFOA, and PFOS emissions in populated areas far from major point sources. Backup QFFs were observed to adsorb some targeted PFAS from the gas-phase, making reported values upper-bounds for particle-phase and lower-bounds for total air (gas plus particle) concentrations. We found that higher concentrations of carbonaceous aerosol were associated with a shift in partitioning of short chain PFCAs and long chain PFSAs toward the particle phase.