Browsing by Author "Ateia, Mohamed"

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    Closing PFAS analytical gaps: Inter-method evaluation of total organofluorine techniques for AFFF-impacted water
    (Elsevier, 2024) Dixit, Fuhar; Antell, Edmund H.; Faber, Katharine A.; Zhang, Chuhui; Pannu, Manmeet W.; Plumlee, Megan H.; Van Buren, Jean; Doroshow, Abraham; Pomerantz, William C. K.; Arnold, William A.; Higgins, Christopher P.; Peaslee, Graham F.; Alvarez-Cohen, Lisa; Sedlak, David L.; Ateia, Mohamed
    Multiple poly- and perfluoroalkyl substances (PFASs) are present in aqueous film-forming foams (AFFF) used for firefighting activities. Currently, no single analytical technique provides a complete accounting of total PFASs or total organofluorine content in AFFF-contaminated samples. To provide insight into the performance of existing methods, we compared ten previously described PFAS measurement techniques. In AFFF-amended tap water, US EPA Methods 533 and 1633, adsorbable organic fluorine with particle induced gamma emission spectroscopy (AOF-PIGE) and fluorine-19 nuclear magnetic resonance (19F NMR) provided similar estimates of total fluorine. The total oxidizable precursor (TOP) assay, suspect screening, and adsorbable organic fluorine with combustion ion chromatography (AOF-CIC) yielded estimates of total organic fluorine that were about two to three times higher than the other techniques. Proximate to AFFF sources, suspect screening and modified EPA Method 1633 yielded higher results, while the TOP assay results were between the other two sets of analyses. Further from sources, suspect screening, modified EPA Method 1633, and the TOP assay yielded similar results that were 4-fold higher than results from targeted quantification methods, such as EPA Method 1633. These results are consistent with expectations about PFAS behavior and inform the selection of analytical techniques used for PFAS contamination characterization efforts.
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    PFAS occurrence and distribution in yard waste compost indicate potential volatile loss, downward migration, and transformation
    (Royal Society of Chemistry, 2024) Saha, Biraj; Ateia, Mohamed; Fernando, Sujan; Xu, Jiale; DeSutter, Thomas; Iskander, Syeed Md
    We discovered high concentrations of PFAS (18.53 ± 1.5 μg kg−1) in yard waste compost, a compost type widely acceptable to the public. Seventeen out of forty targeted PFAS, belonging to six PFAS classes were detected in yard waste compost, with PFCAs (13.51 ± 0.99 μg kg−1) and PFSAs (4.13 ± 0.19 μg kg−1) being the dominant classes, comprising approximately 72.5% and 22.1% of the total measured PFAS. Both short-chain PFAS, such as PFBA, PFHxA, and PFBS, and long-chain PFAS, such as PFOA and PFOS, were prevalent in all the tested yard waste compost samples. We also discovered the co-occurrence of PFAS with low-density polyethylene (LDPE) and polyethylene terephthalate (PET) plastics. Total PFAS concentrations in LDPE and PET separated from incoming yard waste were 7.41 ± 0.41 μg kg−1 and 1.35 ± 0.1 μg kg−1, which increased to 8.66 ± 0.81 μg kg−1 in LDPE and 5.44 ± 0.56 μg kg−1 in PET separated from compost. An idle mature compost pile revealed a clear vertical distribution of PFAS, with the total PFAS concentrations at the surface level approximately 58.9–63.2% lower than the 2 ft level. This difference might be attributed to the volatile loss of short-chain PFCAs, PFAS's downward movement with moisture, and aerobic transformations of precursor PFAS at the surface.