Selective Accumulation of Polychlorocamphenes in Aquatic Biota From the Canadian Arctic

Abstract

Polychlorocamphenes (PCCs; e.g., toxaphene) are major organochlorine contaminants in fish, marine mammals, and other aquatic life from the Arctic. Because PCCs yield complex GC patterns that are often greatly altered in environmental samples compared to a toxaphene standard, identification by GC with electron-capture detection is problematic. We examined PCC profiles in the blubber of narwhal (Monodon monoceros) and the liver of freshwater burbot (Lota Iota) from the Canadian Arctic by GC-negative ion mass spectrometry (GC-NIMS). Chromatograms of these specimens showed that certain PCCs were greatly enriched, compared to a toxaphene standard. Mass spectra of accumulated PCCs were consistent with octachloro-and nonachlorobornanes, with possible contribution from chlorinated bornenes. Corresponding GC peaks in the toxaphene standard appeared to be mixtures of seven-and eight-chlorine or eight-and nine-chlorine PCCs. The same peaks in biological samples showed selective accumulation of the more highly chlorinated components. To properly characterize the levels and biological effects of PCCs in arctic food chains will require isolation or synthesis of pure PCC congeners and an evaluation of their physicochemical and toxicological properties.

Environmental contaminants and biomarker responses in fish from the Rio Grande and its U.S. tributaries: Spatial and temporal trends

“…3), which is consistent with recently reported concentrations at this site (TNRCC, 1994b(TNRCC, , 1997Davis et al, 1995). These values are also similar to those in fish collected from cotton-farming regions of the MRB in 1995 (Schmitt, 2002a;Schmitt et al, 2002) and may be sufficiently high to represent a threat to fish; however, the toxicity of weathered toxaphene is highly variable and cannot be determined from the 1997 data, which is based on a relatively low-resolution analytical procedure (Bidleman et al, 1993;Muir et al, 1999). Toxaphene is also a component of the fish consumption advisory for the Arroyo Colorado and nearby waters.…”

Environmental Contaminants in Fish and Their Associated Risk to Piscivorous Wildlife in the Yukon River Basin, Alaska

“…Although technical toxaphene is highly toxic to fish (Johnson and Finley 1980), adverse effects on freshwater fish have not been associated with whole-body residues <1000 ng/g in laboratory studies (Jarvinen and Ankley 1999). Environmentally weathered toxaphene residues are highly complex and variable, and higher-resolution methods are necessary to characterize their composition and potential toxicity in field studies (e.g., Bidleman et al 1993;Gooch and Matsumura 1987;Harder et al 1983;Muir and de Boer 1993;Ribick et al 1982;Swackhamer and Hites 1987). Concentrations of p,p¢-DDE were greater in pike (<10-93 ng/g) from the Mississippi River Basin ) and the Rio Grande Basin compared to those in YRB pike (<0.4-3.5 ng/g).…”

Polyaromatic hydrocarbons, chlorinated and brominated organic contaminants as tracers of feeding ecology in polar benthic amphipods

“…However, studies on the benthic amphipod Eurythenes gryllus from the Canadian Arctic in the late 1980s revealed OC concentrations in the range found in marine mammals and seabirds , Bidleman et al 1993. Benthic organisms with a close association to the sediment often have higher OC concentrations than pelagic organisms at the same trophic level, due to high affinity of the OCs to the sediment particles and thereby transport from the water column to the sea floor (Bright et al 1995).…”

“…A recent study from the Canadian Arctic confirmed high OC levels in another benthic amphipod, Anonyx nugax (Fisk et al 2003). These high OC levels may have resulted from scavenging upon carcasses of marine mammals with high levels of OC, and these benthic amphipods could perhaps be compared with top predators regardless of their small size , Bidleman et al 1993, Fisk et al 2003. Unfortunately, limited information is available on the feeding ecology of these benthic amphipods, and only few studies have been conducted to investigate feeding dynamics and behavior in E. gryllus and other carrion-feeding species (Hargrave 1985, Sainte-Marie 1992, Hargrave et al 1994.…”