Cytochrome P4501A biomarker indication of oil exposure in harlequin ducks up to 20 years after the Exxon Valdez oil spill

Centre for Wildlife Ecology, Simon Fraser University, 5421 Robertson Road, Delta, British Columbia, V4K 3N2 Canada.
Environmental Toxicology and Chemistry (Impact Factor: 3.23). 05/2010; 29(5):1138-45. DOI: 10.1002/etc.129
Source: PubMed


Hydrocarbon-inducible cytochrome P4501A (CYP1A) expression was measured, as ethoxyresorufin-O-deethylase (EROD) activity, in livers of wintering harlequin ducks (Histrionicus histrionicus) captured in areas of Prince William Sound, Alaska, USA, oiled by the 1989 Exxon Valdez spill and in birds from nearby unoiled areas, during 2005 to 2009 (up to 20 years following the spill). The present work repeated studies conducted in 1998 that demonstrated that in harlequin ducks using areas that received Exxon Valdez oil, EROD activity was elevated nearly a decade after the spill. The present findings strongly supported the conclusion that average levels of hepatic EROD activity were higher in ducks from oiled areas than those from unoiled areas during 2005 to 2009. This result was consistent across four sampling periods; furthermore, results generated from two independent laboratories using paired liver samples from one of the sampling periods were similar. The EROD activity did not vary in relation to age, sex, or body mass of individuals, nor did it vary strongly by season in birds collected early and late in the winter of 2006 to 2007, indicating that these factors did not confound inferences about observed differences between oiled and unoiled areas. We interpret these results to indicate that harlequin ducks continued to be exposed to residual Exxon Valdez oil up to 20 years after the original spill. This adds to a growing body of literature suggesting that oil spills have the potential to affect wildlife for much longer time frames than previously assumed.

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Available from: Samuel A Iverson, Nov 21, 2014
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    • "Alternative monitoring techniques such as PAH metabolite bile burden and the induction of cytochrome P450 1A have been developed (Trust et al. 2000; Troisi et al. 2006). However, these techniques and liver tissue assays require freshly killed animals or intensive field surgeries (Esler et al. 2010; Rothscales et al. 2011; Velando et al. 2010). Recent non-destructive blood monitoring and dose–effect studies have addressed the potential for, and the sub-lethal effects of, persistent chronic exposure to low levels of petroleum hydrocarbons in seabirds (Troisi and Borjesson 2005; Alonso-Alvarez et al. 2007; Perez et al. 2008). "
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    Ecotoxicology 03/2015; 24(5). DOI:10.1007/s10646-015-1450-8 · 2.71 Impact Factor
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    • "creating long-term physiological effects in terrestrial vertebrates (Mendelssohn et al. 2012). For example, Exxon Valdez oil persisted in sediment for at least 16 years (Short et al. 2007), and harlequin ducks (Histrionicus histrionicus) showed evidence of PAH exposure even 20 years later (Esler et al. 2010). with cascading adverse effects for higher trophic levels. "
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    BioScience 09/2014; 64(9):820-828. DOI:10.1093/biosci/biu124 · 5.38 Impact Factor
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    • "Oil reached a number of wetland habitats (Bik et al. 2012; Silliman et al. 2012) and entered some components of the planktonic base of the region's nearshore food web (Graham et al. 2010). Past oil spills have had both immediate and long-term impacts on seabird and other wildlife populations (Golet et al. 2002; Peterson et al. 2003; Alonso-Alvarez et al. 2007a; Esler et al. 2010). Immediate impacts with images of oiled individuals receive the greatest attention, but sublethal effects due to chronic exposure are only recently being explored (Esler et al. 2002; Alonso-Alvarez et al. 2007b). "
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