Polychlorinated biphenyls and 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin equivalents in tree swallows from the upper Hudson River, New York State, USA

Abstract

Abstract-The upper Hudson River of New York State, USA, is contaminated with polychlorinated biphenyls (PCBs) as a result of industrial discharges throughout the latter half of this century. In 1994 and 1995, we monitored the transfer of PCBs from aquatic sediments to a terrestrial wildlife community using the tree swallow (Tachycineta bicolor) as a model organism. Tree swallow eggs and nestlings were collected at four colonies established along a 40-km stretch of the upper Hudson River watershed. Samples were analyzed for total PCBs and PCB congeners, including non-ortho-and mono-ortho-substituted PCBs. Mean concentrations of PCBs in tree swallow eggs and nestlings ranged from 721 to 62,200 ng/g and were as much as 15 times greater than PCB concentrations in tree swallow eggs and nestlings collected from PCB-contaminated areas within the Great Lakes ecosystem. The corresponding 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) calculated using avian toxic equivalency factors ranged from 410 to 25,400 pg/g. Concentrations of PCB congener 77 (3,3Ј,4,4Ј-tetrachlorobiphenyl) were extremely elevated and were major contributors to the calculated TEQs. Homologue pattern comparisons between Hudson River and Saginaw River (Michigan, USA) ecosystems supported the hypothesis that a consistent Hudson River PCB source was the major contributor to PCBs in Hudson River tree swallows. The high concentrations of PCBs in Hudson River sediments and resultant concentrations observed in tree swallows were indicative of a potential elevated risk to these and other wildlife linked to the aquatic food web of the Hudson River ecosystem.

Exposure and effects of chemical contaminants on tree swallows nesting along the Housatonic River, Berkshire County, Massachusetts, USA, 1998–2000

“…In Green Bay, Lake Michigan, tree swallows accumulated on average 1.3 to 6.7 g/d [4]. Along the Hudson River in New York, however, individual accumulation rates varied between 3.5 and 158 g/d with 67% of those accumulation rates being Ͻ50 g/d [15]. The maximum individual accumulation rate along the Housatonic River was 104 g/d.…”

Polychlorinated biphenyls, dioxins, furans, and organochlorine pesticides in belted kingfisher eggs from the upper Hudson River basin, New York, USA

“…Between 1 and 5% of those PCBs may have been released into the Hudson River [1], leaving the sediments highly contaminated with PCBs. This makes the Hudson River one of the most PCB-contaminated rivers in the country [2].…”

“…A number of studies have documented that birds can accumulate PCBs through their diet [2][3][4][5][6][7]. In either adults or eggs, PCBs can reach concentrations that may cause toxic effects [8,9].…”

“…One recent set of studies examined tree swallows (Tachycineta bicolor) in the Hudson River basin. Tree swallows nesting along the Hudson River near Fort Edward had PCB concentrations up to 114 mg/g wet weight in adult whole bodies [2]. Concentrations of PCBs in eggs ranged from 9.3 to 29.5 mg/g wet weight, while concentrations in nestlings ranged from 3.7 to 62.2 mg/g wet weight [11].…”

Dietary exposure of three passerine species to PCDD/DFs from the Chippewa, Tittabawassee, and Saginaw River floodplains, Midland, Michigan, USA

“…The mixture of chlorinated hydrocarbons in the SA is dominated by a few PCDF congeners, which makes it distinctive compared to other locations contaminated with PCB mixtures or PCDDs (Custer et al 2002(Custer et al , 2005Froese et al 1998;Harris and Elliott 2000;Neigh et al 2006b, c;Secord et al 1999;Shaw 1983;Smits et al 2005;Spears et al 2008). Furthermore, based on chemical characteristics and best estimates of historical production data, it is likely that this unique mixture has been in place for almost a century, with most of the materials being released prior to the 1950s (ATS 2007(ATS , 2009.…”