title: Human exposure to per- and polyfluoroalkyl substances (PFASs) via house dust in Korea: Implication to exposure pathway.
abstract: A wide range of per- and polyfluoroalkyl substances (PFASs), including fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamidoethanols (FOSEs), perfluoroalkyl carboxylic acids (PFCAs), and perfluoroalkane sulfonic acids (PFSAs), were measured in fifteen house dust and two nonresidential indoor dust of Korea. Total concentrations of PFASs in house dust ranged from 29.9 to 97.6 ng g(-1), with a dominance of perfluorooctane sulfonic acid (PFOS), followed by 8:2 FTOH, N-Ethyl perfluorooctane sulfonamidoethanol (EtFOSE), perfluoroctanoic acid (PFOA). In a typical exposure scenario, the estimated daily intakes (EDIs) of total PFASs via house dust ingestion were 2.83 ng d(-1) for toddlers and 1.13 ng d(-1) for adults, which were within the range of the mean EDIs reported from several countries. For PFOA and PFOS exposure via house dust ingestion, indirect exposure (via precursors) was a minor contributor, accounting for 5% and 12%, respectively. An aggregated exposure (hereafter, overall-EDIs) of PFOA and PFOS occurring via all pathways, estimated using data compiled from the literature, were 53.6 and 14.8 ng d(-1) for toddlers, and 20.5 and 40.6 ng d(-1) for adults, respectively, in a typical scenario. These overall-EDIs corresponded to 82% (PFOA) and 92% (PFOS) of a pharmacokinetic model-based EDIs estimated from adults' serum data. Direct dietary exposure was a major contributor (>89% of overall-EDI) to PFOS in both toddlers and adults, and PFOA in toddlers. As for PFOA exposure of adults, however direct exposure via tap water drinking (37%) and indirect exposure via inhalation (22%) were as important as direct dietary exposure (41%). House dust-ingested exposure (direct+indirect) was responsible for 5% (PFOS in toddlers) and <1% (PFOS in adults, and PFOA in both toddlers and adults) of the overall-EDIs. In conclusion, house-dust ingestion was a minor contributor in this study, but should not be ignored for toddlers' PFOS exposure due to its significance in the worst-case scenario.
authors.affiliation: Department of Life Sciences, Incheon National University, 119 Academy-ro (Songdo-dong), Yeonsu-gu, Incheon 22012, Republic of Korea.
authors.forename: Zhexi
authors.initials: Z
authors.lastname: Tian
authors.affiliation: Department of Marine Science, College of Natural Sciences, Incheon National University, 119 Academy-ro (Songdo-dong), Yeonsu-gu, Incheon 22012, Republic of Korea; Research Institute of Natural Sciences, Incheon National University, 119 Academy-ro (Songdo-dong), Yeonsu-gu, Incheon 22012, Republic of Korea. Electronic address: skkim@inu.ac.kr.
authors.forename: Seung-Kyu
authors.initials: SK
authors.lastname: Kim
authors.affiliation: Environment Canada, Science and Technology Branch, 4905 Dufferin Street, Toronto, Ontario M3H 5T4, Canada.
authors.forename: Mahiba
authors.initials: M
authors.lastname: Shoeib
authors.affiliation: Department of Civil and Environmental Engineering, Pusan National University, Busan 609-735, Republic of Korea.
authors.forename: Jeong-Eun
authors.initials: JE
authors.lastname: Oh
authors.affiliation: National Institute of Environmental Research, Environmental Research Complex, Kyungseo-dong, Seo-gu, Incheon 404-708, Republic of Korea.
authors.forename: Jong-Eun
authors.initials: JE
authors.lastname: Park
mesh_terms: D016902:Air Pollution, Indoor / Q000032:analysis* / Q000706:statistics & numerical data; D004391:Dust / Q000032:analysis*; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005466:Fluorocarbons / Q000032:analysis*; D006801:Humans; D056910:Republic of Korea
chemical_list: D004391:Dust; D005466:Fluorocarbons
keywords: Daily intake; Emerging POPs; Exposure assessment; House dust; Indoor environment; Per- and polyfluoroalkyl substances (PFASs)