title: Current-use pesticides in seawater and their bioaccumulation in polar bear-ringed seal food chains of the Canadian Arctic.
abstract: The distribution of current-use pesticides (CUPs) in seawater and their trophodynamics were investigated in 3 Canadian Arctic marine food chains. The greatest ranges of dissolved-phase concentrations in seawater for each CUP were endosulfan sulfate (less than method detection limit (MDL) to 19 pg L(-1) ) > dacthal (0.76-15 pg L(-1) ) > chlorpyrifos (less than MDL to 8.1 pg L(-1) ) > pentachloronitrobenzene (less than MDL to 2.6 pg L(-1) ) > α-endosulfan (0.20-2.3 pg L(-1) ). Bioaccumulation factors (BAFs, water-respiring organisms) were greatest in plankton, including chlorothalonil (log BAF = 7.4 ± 7.1 L kg(-1) , mean ± standard error), chlorpyrifos (log BAF = 6.9 ± 6.7 L kg(-1) ), and α-endosulfan (log BAF = 6.5 ± 6.0 L kg(-1) ). The largest biomagnification factors (BMFs) were found for dacthal in the capelin:plankton trophic relationship (BMF = 13 ± 5.0) at Cumberland Sound (Nunvavut), and for β-endosulfan (BMF = 16 ± 4.9) and α-endosulfan (BMF = 9.3 ± 2.8) in the polar bear-ringed seal relationship at Barrow and Rae Strait (NU), respectively. Concentrations of endosulfan sulfate exhibited trophic magnification (increasing concentrations with increasing trophic level) in the poikilothermic portion of the food web (trophic magnification factor = 1.4), but all of the CUPs underwent trophic dilution in the marine mammal food web, despite some trophic level-specific biomagnification. Together, these observations are most likely indicative of metabolism of these CUPs in mammals. Environ Toxicol Chem 2016;35:1695-1707. © 2016 SETAC.
authors.affiliation: School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada.
authors.forename: Adam D
authors.initials: AD
authors.lastname: Morris
authors.affiliation: School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada.|Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario, Canada.
authors.forename: Derek C G
authors.initials: DC
authors.lastname: Muir
authors.affiliation: School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada.
authors.forename: Keith R
authors.initials: KR
authors.lastname: Solomon
authors.affiliation: Wildlife and Landscape Science Directorate, Environment and Climate Change Canada, Ottawa, Ontario, Canada.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Letcher
authors.affiliation: Department of Natural Resources and the Environment, University of Connecticut, Mansfield, Connecticut, USA.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: McKinney
authors.affiliation: Great Lakes Institute of Environmental Research, University of Windsor, Windsor, Ontario, Canada.
authors.forename: Aaron T
authors.initials: AT
authors.lastname: Fisk
authors.affiliation: Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada.
authors.forename: Bailey C
authors.initials: BC
authors.lastname: McMeans
authors.affiliation: Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: Gregg T
authors.initials: GT
authors.lastname: Tomy
authors.affiliation: Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario, Canada.
authors.forename: Camilla
authors.initials: C
authors.lastname: Teixeira
authors.affiliation: Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario, Canada.
authors.forename: Xiaowa
authors.initials: X
authors.lastname: Wang
authors.affiliation: Aquatic Contaminants Research Division, Environment and Climate Change Canada, Burlington, Ontario, Canada.
authors.forename: Mark
authors.initials: M
authors.lastname: Duric
mesh_terms: D000818:Animals; D001110:Arctic Regions; D002170:Canada; D004784:Environmental Monitoring / Q000379:methods*; D020387:Food Chain; D010575:Pesticides / Q000032:analysis* / Q000378:metabolism; D046048:Seals, Earless / Q000378:metabolism*; D012623:Seawater / Q000737:chemistry*; D001503:Ursidae / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D010575:Pesticides; D014874:Water Pollutants, Chemical
keywords: Bioaccumulation; Current-use pesticide; Food chain; Marine mammal; Trophic dilution