title: Wastewater treatment plant and landfills as sources of polyfluoroalkyl compounds to the atmosphere.
abstract: Polyfluoroalkyl compounds (PFCs) were determined in air around a wastewater treatment plant (WWTP) and two landfill sites using sorbent-impregnated polyurethane foam (SIP) disk passive air samplers in summer 2009. The samples were analyzed for five PFC classes (i.e., fluorotelomer alcohols (FTOHs), perfluorooctane sulfonamides (FOSAs), sulfonamidoethanols (FOSEs), perfluoroalkyl sulfonic acids (PFSAs), and perfluoroalkyl carboxylic acids (PFCAs)) to investigate their concentration in air, composition and emissions to the atmosphere. ∑PFC concentrations in air were 3-15 times higher within the WWTP (2280-24 040 pg/m(3)) and 5-30 times higher at the landfill sites (2780-26 430 pg/m(3)) compared to the reference sites (597-1600 pg/m3). Variations in the PFC pattern were observed between the WWTP and landfill sites and even within the WWTP site. For example, FTOHs were the predominant PFC class in air for all WWTP and landfill sites, with 6:2 FTOH as the dominant compound at the WWTP (895-12 290 pg/m(3)) and 8:2 FTOH dominating at the landfill sites (1290-17 380 pg/m(3)). Furthermore, perfluorooctane sulfonic acid (PFOS) was dominant within the WWTP (43-171 pg/m(3)), followed by perfluorobutanoic acid (PFBA) (55-116 pg/m(3)), while PFBA was dominant at the landfill sites (101-102 pg/m(3)). It is also noteworthy that the PFCA concentrations decreased with increasing chain length and that the emissions for the even chain length PFCAs outweighed emissions for the odd chain length compounds. Furthermore, highly elevated PFC concentrations were found near the aeration tanks compared to the other tanks (i.e., primary and secondary clarifier) and likely associated with increased volatilization during aeration that may be further enhanced through aqueous aerosol-mediated transport. ∑PFC yearly emissions estimated using a simplified dispersion model were 2560 g/year for the WWTP, 99 g/year for landfill site 1, and 1000 g/year for landfill site 2. These results highlight the important role of WWTPs and landfills as emission sources of PFCs to the atmosphere.
authors.affiliation: Environment Canada, Science and Technology Branch, Toronto, ON, Canada, M3H 5T4. lutz.ahrens@ec.gc.ca
authors.forename: Lutz
authors.initials: L
authors.lastname: Ahrens
authors.forename: Mahiba
authors.initials: M
authors.lastname: Shoeib
authors.forename: Tom
authors.initials: T
authors.lastname: Harner
authors.forename: Sum Chi
authors.initials: SC
authors.lastname: Lee
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Reiner
mesh_terms: D001272:Atmosphere / Q000737:chemistry*; D002170:Canada; D004784:Environmental Monitoring; D005466:Fluorocarbons / Q000032:analysis*; D011140:Polyurethanes / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification
chemical_list: D005466:Fluorocarbons; D011140:Polyurethanes; D014874:Water Pollutants, Chemical; C028279:polyurethane foam