Emission Profiles of Fluorinated Aerosol Precursors from Rain Jackets Measured by I-HR-ToF-CIMS

CLARA EICHLER, Michael Davern, Jason Surratt, Glenn Morrison, Barbara Turpin, UNC-Chapel Hill

     Abstract Number: 93
     Working Group: Chemicals of Emerging Concern in Aerosol: Sources, Transformations, and Impacts

Abstract
Hydroxyl radical oxidation of fluorotelomer alcohols (FTOHs) is a source of secondary organo-fluorine aerosol in the outdoor atmosphere via formation of perfluoroalkyl carboxylic acids (PFCAs). Per- and polyfluoroalkyl substances (PFAS), including FTOHs, are present in many consumer products because of their water- and stain-repellent properties. These products can emit PFAS indoors, where consumer products are frequently stored and used. Therefore, consumer products may contribute to atmospheric FTOH emissions via indoor-to-outdoor transport. However, FTOH sources and emission rates are not well understood. We measured emission rates of 4:2, 6:2, 8:2 and 10:2 FTOH from new, old/used and “PFAS-free” rain jackets under realistic indoor conditions (T = ~20°C, RH = 50%) using a flow tube and iodide high-resolution time-of-flight chemical ionization mass spectrometry (I-HR-ToF-CIMS). When tested immediately “out of package”, we observed high initial emission rates of up to 790 pg/h/cm² followed by a decay for 6:2, 8:2 and 10:2 FTOH. Peak emission rates correlated moderately well (R² = 0.32-0.83) with FTOH material-phase concentrations determined by gas chromatography-mass spectrometry (GC-MS). When the same materials were tested after airing out, resulting emission rates were more constant. This emission behavior is consistent with that of volatile organic compounds (VOCs), rather than semi-volatile organic compounds (SVOCs). The old/used rain jackets we measured exhibited, on average, higher emission rates and contained a broader range of neutral PFAS than the new jacket materials. FTOH emissions from high emitting household fabrics could plausibly explain FTOH concentrations measured in the 11-home Indoor PFAS Assessment (IPA) Campaign.