title: Changes in polychlorinated biphenyl (PCB) exposure in tree swallows (Tachycineta bicolor) nesting along the Sheboygan River, WI, USA.
abstract: Exposure to polychlorinated biphenyls (PCBs) in tree swallow (Tachycineta bicolor) eggs on the Sheboygan River, Wisconsin in the 1990s was higher at sites downstream (geometric means = 3.33-8.69 μg/g wet wt.) of the putative PCB source in Sheboygan Falls, Wisconsin than it was above the source (1.24 μg/g) with the exposure declining as the distance downstream of the source increased. A similar pattern of declining exposure was present in the 2010s as well. Although exposure to PCBs in eggs along the Sheboygan River at sites downstream of Sheboygan Falls has declined by ~60 % since the mid-1990s (8.69 down to 3.27 μg/g) there still seems to be residual pockets of contamination that are exposing some individuals (~25 %) to PCB contamination, similar to exposure found in the 1990s. The exposure patterns in eggs and nestlings among sites, and the changes between the two decades, are further validated by accumulation rate information.
authors: U.S. Geological Survey, 2630 Fanta Reed Rd, La Crosse, WI, 54603, USA, ccuster@usgs.gov.
authors: Christine M
authors: CM
authors: Custer
authors: Thomas W
authors: TW
authors: Custer
authors: Sean M
authors: SM
authors: Strom
authors: Kathleen A
authors: KA
authors: Patnode
authors: J
authors: J
authors: Christian Franson
mesh_terms: D000818:Animals; D004781:Environmental Exposure; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D010063:Ovum / Q000737:chemistry*; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D045483:Rivers / Q000737:chemistry; D046388:Swallows; D014922:Wisconsin
chemical_list: D004785:Environmental Pollutants; D011078:Polychlorinated Biphenyls