Particle-Phase Ionic Per- and Polyfluoroalkyl Substance (PFAS) Profiles, Concentrations, and Artifacts in Indoor Air: Findings from the Indoor PFAS Assessment (IPA) Campaign
NAOMI CHANG, Clara Eichler, Daniel Amparo, Jiaqi Zhou, Elaine Cohen Hubal, Jason Surratt, Glenn Morrison, Barbara Turpin,
UNC-Chapel Hill Abstract Number: 102
Working Group: Indoor Aerosols
AbstractPFAS are a class of >12,000 synthetic compounds that persist in the environment, and some have been associated with adverse health effects including cancers and reduced immune response in children. Although PFAS-containing consumer products are commonly used indoors, few indoor air measurements of PFAS have been reported. To address this knowledge gap, the UNC Indoor PFAS Assessment (IPA) Campaign sampled various environmental matrices in 10 homes in North Carolina over 9-months. Quartz fiber filters (QFF) are the standard collection substrate for particle-phase PFAS. However, QFFs are known to adsorb organic gases, in addition to collecting particles. Thus, in the IPA Campaign, we collected PM
2.5 with two QFFs in series (6-day collection), where the backup QFF provides an estimate of the adsorption artifact. PFAS were quantified using an AB Sciex Triple Quad UHPLC-ESI-MS/MS for 26 ionic PFAS. Eight PFAS (6:2 diPAP, PFBA, PFHpA, PFHpS, PFHxA, PFOA, PFOS, and PFTA) were above detection limits in over 50% of front and/or backup QFFs indicating gas-phase adsorption to both filters. Front filter concentrations of PFOA and PFOS were significantly higher than backup filter concentrations, suggesting that particle-phase PFOA and PFOS were present on the front filter. For the conditions of this study, at least 29% and 37%, respectively, of the median front filter concentrations of PFOA (0.58 pg/m
3) and PFOS (0.56 pg/m
3) are attributable to gas-phase adsorption. Therefore, previously reported particle-phase PFAS concentrations may be overestimates. We are investigating other feasible filter collection methods for separate gas and particle-phase collection. To our knowledge, the IPA Campaign is the first study to report PM
2.5 filter collected ionic PFAS in United States homes.
Disclaimer: The views expressed in this presentation are those of the authors and do not necessarily represent the views or policies of the U.S. EPA.