title: Fate and transport of perfluoro- and polyfluoroalkyl substances including perfluorooctane sulfonamides in a managed urban water body.
abstract: Transport and fate of perfluoro- and polyfluoroalkyl substances (PFASs) in an urban water body that receives mainly urban runoff was investigated. Water, suspended solids, and sediment samples were collected during the monsoon (wet) and inter-monsoon (dry) season at different sites and depths. Samples were analyzed for C7 to C12 perfluoroalkyl carboxylate homologues (PFCAs) (PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA), perfluorohexane, perfluorooctane, and 6:2-fluorotelomer sulfonate (PFHxS, PFOS, and 6:2FtS, respectively), perfluorooctane sulfonamide (FOSA), N-ethyl FOSA (sulfluramid), N-ethyl sulfonamidoethanol (N-EtFOSE), and N-methyl and N-ethyl sulfonamidoacetic acid (N-EtFOSAA and N-MeFOSAA, respectively). Concentrations in wet samples were only slightly higher. The sum total PFAS (ΣPFAS) concentrations dissolved in the aqueous phase and sorbed to suspended solids (SS) ranged from 107 to 253 ng/L and 11 to 158 ng/L, respectively. PFOA, PFOS, PFNA, PFHxS, and PFDA contributed most (approximately 90 %) to the dissolved ΣPFASs. N-EtFOSA dominated the particulate PFAS burden in wet samples. K D values of PFOA and PFOS calculated from paired SS and water concentrations varied widely (1.4 to 13.7 and 1.9 to 98.9 for PFOA and PFOS, respectively). Field derived K D was significantly higher than laboratory K D suggesting hydrophobic PFASs sorbed to SS resist desorption. The ΣPFAS concentrations in the top sedimentary layer ranged from 8 to 42 μg/kg and indicated preferential accumulation of the strongly sorbing long-chain PFASs. The occurrence of the metabolites N-MeFOSAA, N-EtFOSAA and FOSA in the water column and sediments may have resulted from biological or photochemical transformations of perfluorooctane sulfonamide precursors while the absence of FOSA, N-EtFOSA and 6:2FtS in sediments was consistent with biotransformation.
authors.affiliation: Public Utilities Board (PUB), Environment Building, 40 Scotts Road, Singapore, 228231, Singapore.
authors.forename: Tung V
authors.initials: TV
authors.lastname: Nguyen
authors.affiliation: Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, E1A 07-03, Singapore, 117576, Singapore. reinhard@stanford.edu.|Department of Civil and Environmental Engineering, Stanford University, Stanford, CA, 94305, USA. reinhard@stanford.edu.
authors.forename: Martin
authors.initials: M
authors.lastname: Reinhard
authors.affiliation: Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, E1A 07-03, Singapore, 117576, Singapore.
authors.forename: Huiting
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, E1A 07-03, Singapore, 117576, Singapore.|NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, #02-01, Singapore, 117411, Singapore.
authors.forename: Karina Y-H
authors.initials: KY
authors.lastname: Gin
mesh_terms: D017738:Alkanesulfonic Acids / Q000032:analysis; D001711:Biotransformation; D004784:Environmental Monitoring; D005466:Fluorocarbons / Q000032:analysis / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry; D006845:Hydrocarbons, Fluorinated / Q000032:analysis; D012846:Singapore; D013449:Sulfonamides / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014881:Water Supply
chemical_list: C000601538:2-(N-methylperfluorooctanesulfonamido)acetic acid; D017738:Alkanesulfonic Acids; D005466:Fluorocarbons; D006845:Hydrocarbons, Fluorinated; C542083:N-ethyl perfluorooctane sulfonamido acetate; D013449:Sulfonamides; D014874:Water Pollutants, Chemical; C073608:perfluorooctane; C063900:perfluorooctanesulfonamide; C078626:perflexane; C063732:sulfluramid
keywords: Perfluorinated compounds; Perfluorooctane sulfonamide; Sediment; Suspended solids; Transport; Urban runoff