title: Organophosphate pesticide method development and presence of chlorpyrifos in the feet of nearctic-neotropical migratory songbirds from Canada that over-winter in Central America agricultural areas.
abstract: Recent modeling analysis suggests that numerous birds may be at risk of acute poisoning in insecticide-treated fields. Although the majority of avian field studies on pesticides have focused on treated seed, granule, insect or vegetation (oral exposure) ingestion, dermal exposure is an important exposure route when birds come into contact with deposited pesticides on foliage and other surfaces. Some nearctic-neotropical migratory songbirds are likely exposed to pesticides on their non-breeding habitats and include treated crops, plantations or farmlands. In the present study, we developed a method for four environmentally-relevant organophosphate (OP) pesticides (fenthion, fenamiphos, chlorpyrifos and diazinon) in the feet of migratory songbirds (i.e. Common yellowthroat, Gray catbird, Indigo bunting, America redstart, Northern waterthrush, Northern parula, and an additional 12 species of warblers). A total of 190 specimens of the 18 species of songbirds were sampled from available window-killed birds (spring of 2007 and 2011) in downtown Toronto, Canada. The species that were available most likely over-wintered in Mexican/Central American crops such as citrus, coffee and cacao. The feet of the dead birds were sampled and where OP foot exposure likely occurred during over-wintering foraging on pesticide-treated crops. Chlorpyrifos was the only measurable OP (pg mg feet weight(-1)) and in the 2011-collected feet of Black throated blue warbler (0.5), Tennessee warbler (1.0), Northern parula (1.2), Northern waterthrush (0.6), Common yellowthroat (1.0) and the Blue winged warbler (0.9). Dermal contact with OP pesticides during over-wintering in agricultural areas resulted in low levels of chlorpyrifos and long time retention on the feet of a subset of songbirds.
authors.affiliation: Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3, Canada; Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada. Electronic address: haa478@mail.usask.ca.
authors.forename: Hattan A
authors.initials: HA
authors.lastname: Alharbi
authors.affiliation: Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3, Canada; Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada. Electronic address: robert.letcher@ec.gc.ca.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Letcher
authors.affiliation: Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3, Canada; Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada.
authors.forename: Pierre
authors.initials: P
authors.lastname: Mineau
authors.affiliation: Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3, Canada; Cooperative Wildlife Research Laboratory and Department of Zoology, Southern Illinois University Carbondale, Carbondale, IL 62901, USA.
authors.forename: Da
authors.initials: D
authors.lastname: Chen
authors.affiliation: Ecotoxicology and Wildlife Health Division, Science and Technology Branch, Environment Canada, National Wildlife Research Centre, Carleton University, Ottawa, ON K1A 0H3, Canada.
authors.forename: Shaogang
authors.initials: S
authors.lastname: Chu
mesh_terms: D000383:Agriculture; D025041:Animal Migration; D000818:Animals; D001110:Arctic Regions; D002170:Canada; D002489:Central America; D004390:Chlorpyrifos / Q000032:analysis*; D018556:Crops, Agricultural / Q000254:growth & development; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005528:Foot; D010575:Pesticides / Q000032:analysis*; D012621:Seasons; D020308:Songbirds / Q000378:metabolism*; D013045:Species Specificity; D014329:Tropical Climate
chemical_list: D010575:Pesticides; D004390:Chlorpyrifos
keywords: Chlorpyrifos; Dermal exposure; Liquid chromatography–mass spectrometry; Migratory songbirds; Organophosphate pesticides