Indoor Dynamics of Ionic PFAS: Results from the IPA Campaign

Naomi Chang, Clara Eichler, Daniel Amparo, Elaine Cohen Hubal, Jason Surratt, Glenn Morrison, BARBARA TURPIN, UNC-Chapel Hill

     Abstract Number: 427
     Working Group: Indoor Aerosols

Abstract
Per- and polyfluoroalkyl substances (PFAS) are persistent, bioaccumulative, and present in many consumer products. Some have been associated with adverse health effects like hepatotoxicity and reduced immune response in children. People spend roughly 90% of their time indoors, which is an important place for exposure. However, few concurrent measurements from multiple environmental compartments within homes exist. As part of the UNC Indoor PFAS Assessment (IPA) Campaign, we sampled air (PM2.5 quartz fiber filters; QFF), dust, water, indoor window surfaces, wall-mounted glass slabs, and heating and air conditioning (HAC) filters for 26 ionic PFAS using an AB Sciex Triple Quad (UHPLC-ESI-MS/MS) in 10 homes in North Carolina over 9-months. We compare PFAS species profiles and time series across compartments to develop hypotheses about PFAS sources, dynamics, and chemistry. We use multicompartment measurements to gain insights regarding using HAC filters or windows as convenient indoor PFAS samplers and compare with insights from concurrently measured neutral PFAS. Ionic PFAS were detected in all compartments. On QFFs, which collect particles and some adsorbed vapor, mean PFBA concentrations were highest (12.2 pg m-3; DF = 67%), while PFHxA, PFOA, and PFOS had the highest detection frequency (DF = 80%; medians = 0.5-0.7 pg m-3). Substantial differences were observed between ionic PFAS on glass slabs and windows, which are subject to greater and more variable temperature gradients and sunlight. The ionic PFAS species profile for HAC filters was strongly (R2 = 0.91) and significantly (p < 0.05) linearly associated with a combination of dust (β = 0.6) and QFF-collected PM2.5 (β = 0.1), whereas the pattern of neutral PFAS on HAC filters was predominantly explained by dust.

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.