title: Perfluoroalkyl acids in the Canadian environment: multi-media assessment of current status and trends.
abstract: In Canada, perfluoroalkyl acids (PFAAs) have been the focus of several monitoring programs and research and surveillance studies. Here, we integrate recent data and perform a multi-media assessment to examine the current status and ongoing trends of PFAAs in Canada. Concentrations of perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), and other long-chain perfluorocarboxylates (PFCAs) in air, water, sediment, fish, and birds across Canada are generally related to urbanization, with elevated concentrations observed around cities, especially in southern Ontario. PFOS levels in water, fish tissue, and bird eggs were below their respective Draft Federal Environmental Quality Guidelines, suggesting there is low potential for adverse effects to the environment/organisms examined. However, PFOS in fish and bird eggs tended to exceed guidelines for the protection of mammalian and avian consumers, suggesting a potential risk to their wildlife predators, although wildlife population health assessments are needed to determine whether negative impacts are actually occurring. Long-term temporal trends of PFOS in suspended sediment, sediment cores, Lake Trout (Salvelinus namaycush), and Herring Gull (Larus argentatus) eggs collected from Lake Ontario increased consistently from the start of data collection until the 1990s. However, after this time, the trends varied by media, with concentrations stabilizing in Lake Trout and Herring Gull eggs, and decreasing and increasing in suspended sediment and the sediment cores, respectively. For PFCAs, concentrations in suspended sediment, sediment cores, and Herring Gulls generally increased from the start of data collection until present and concentrations in Lake Trout increased until the late 1990s and subsequently stabilized. A multimedia comparison of PFAA profiles provided evidence that unexpected patterns in biota of some of the lakes were due to unique source patterns rather than internal lake processes. High concentrations of PFAAs in the leachate and air of landfill sites, in the wastewater influent/effluent, biosolids, and air at wastewater treatment plants, and in indoor air and dust highlight the waste sector and current-use products (used primarily indoors) as ongoing sources of PFAAs to the Canadian environment. The results of this study demonstrate the utility of integrating data from different media. Simultaneous evaluation of spatial and temporal trends in multiple media allows inferences that would be impossible with data on only one medium. As such, more co-ordination among monitoring sites for different media is suggested for future sampling, especially at the northern sites. We emphasize the importance of continued monitoring of multiple-media for determining future responses of environmental PFAA concentrations to voluntary and regulatory actions.
authors.affiliation: Conestoga-Rovers & Associates, 651 Colby Drive, Waterloo, ON, N2V 1C2, Canada.
authors.forename: Sarah B
authors.initials: SB
authors.lastname: Gewurtz
authors.forename: Sean M
authors.initials: SM
authors.lastname: Backus
authors.forename: Amila O
authors.initials: AO
authors.lastname: De Silva
authors.forename: Lutz
authors.initials: L
authors.lastname: Ahrens
authors.forename: Alain
authors.initials: A
authors.lastname: Armellin
authors.forename: Marlene
authors.initials: M
authors.lastname: Evans
authors.forename: Susan
authors.initials: S
authors.lastname: Fraser
authors.forename: Melissa
authors.initials: M
authors.lastname: Gledhill
authors.forename: Paula
authors.initials: P
authors.lastname: Guerra
authors.forename: Tom
authors.initials: T
authors.lastname: Harner
authors.forename: Paul A
authors.initials: PA
authors.lastname: Helm
authors.forename: Hayley
authors.initials: H
authors.lastname: Hung
authors.forename: Nav
authors.initials: N
authors.lastname: Khera
authors.forename: Min Gu
authors.initials: MG
authors.lastname: Kim
authors.forename: Martha
authors.initials: M
authors.lastname: King
authors.forename: Sum Chi
authors.initials: SC
authors.lastname: Lee
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Letcher
authors.forename: Pamela
authors.initials: P
authors.lastname: Martin
authors.forename: Chris
authors.initials: C
authors.lastname: Marvin
authors.forename: Daryl J
authors.initials: DJ
authors.lastname: McGoldrick
authors.forename: Anne L
authors.initials: AL
authors.lastname: Myers
authors.forename: Magella
authors.initials: M
authors.lastname: Pelletier
authors.forename: Joe
authors.initials: J
authors.lastname: Pomeroy
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Reiner
authors.forename: Myriam
authors.initials: M
authors.lastname: Rondeau
authors.forename: Marie-Claude
authors.initials: MC
authors.lastname: Sauve
authors.forename: Mark
authors.initials: M
authors.lastname: Sekela
authors.forename: Mahiba
authors.initials: M
authors.lastname: Shoeib
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Smith
authors.forename: Shirley Anne
authors.initials: SA
authors.lastname: Smyth
authors.forename: John
authors.initials: J
authors.lastname: Struger
authors.forename: Doug
authors.initials: D
authors.lastname: Spry
authors.forename: Jim
authors.initials: J
authors.lastname: Syrgiannis
authors.forename: Jasmine
authors.initials: J
authors.lastname: Waltho
mesh_terms: D017738:Alkanesulfonic Acids / Q000032:analysis*; D000818:Animals; D001717:Birds; D002210:Caprylates / Q000032:analysis*; D004531:Eggs / Q000032:analysis; D004784:Environmental Monitoring; D005399:Fishes; D005466:Fluorocarbons / Q000032:analysis*; D060106:Lakes / Q000737:chemistry; D009864:Ontario; D064091:Waste Disposal Facilities; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D017738:Alkanesulfonic Acids; D002210:Caprylates; D005466:Fluorocarbons; D014874:Water Pollutants, Chemical; C023036:perfluorooctanoic acid; C076994:perfluorooctane sulfonic acid
keywords: Canada; Federal environmental quality guidelines; Multi-media analysis; Perfluoroalkyl acids; Potential sources; Trends