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.

Download full-text


Available from: Samuel A Iverson, Nov 21, 2014
22 Reads
  • Source
    • "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. "
    [Show abstract] [Hide abstract]
    ABSTRACT: In addition to external oiling, marine oil spills may affect vertebrate animals through degradation of habitat; alterations in food web structure; and contamination of resources by toxic compounds, including polycyclic aromatic hydrocarbons. These processes are not well understood for vertebrates breeding and foraging in terrestrial ecosystems affected by oil, such as coastal marshes that were heavily oiled following the 2010 Macondo oil spill. Here, we review what is known about the ecological and physiological effects of oil exposure on vertebrates in general. We then apply these concepts to salt-marsh vertebrates, with special reference to our ongoing monitoring of impacts and recovery in the seaside sparrow (Ammodramus maritimus) and marsh rice rat (Oryzomys palustris) in Louisiana following the Macondo spill.
    BioScience 09/2014; 64(9):820-828. DOI:10.1093/biosci/biu124 · 5.38 Impact Factor
  • Source
    • "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). "
    [Show abstract] [Hide abstract]
    ABSTRACT: On 20 April 2010, the Deepwater Horizon oil drilling rig located 66 km southeast of the Louisiana coast exploded and, by the time the pipeline was capped in July, estimates of 4.9 million barrels of oil were released in the northern Gulf of Mexico. Polycyclic aromatic hydrocarbons make up a small percentage of petroleum (< 5%), but are the most toxic with known negative impacts on wildlife and humans. Because of their lifestyle and trophic standing, seabirds are often impacted by marine spills. To test for the presence of polycyclic aromatic hydrocarbons, we captured and tested blood in Common Loons (Gavia immer), a winter migrant that spends 4-5 months in the Gulf of Mexico. Common Loons were captured at night, using spotlighting and a large dip net off the Louisiana coast, during January-March in 2011 and 2012. A total of 38 Common Loons were caught and sampled (17 in 2011 and 21 in 2012). Both the concentrations and frequency of polycyclic aromatic hydrocarbons present in Common Loons appear to be increasing between years; however, concentrations were low (< 10 ppb). In 2012, petrogenic alkyl polycyclic aromatic hydrocarbons, those derived from petroleum, were significantly higher than pyrogenic polycyclic aromatic hydrocarbons, derived from combustion and anthropogenic sources. It remains unknown if current levels have any adverse impacts on Common Loon health, reproduction and survival.
    Waterbirds 04/2014; 37:85-93. DOI:10.1675/063.037.sp111 · 0.64 Impact Factor
  • Source
    • "Researchers disagree on the rate of recovery. Seventeen years after the Exxon Valdez oil spill it was concluded that the ecosystem had effectively recovered (Harwell and Gentile 2006), whereas, a recent study indicates that wildlife is still exposed to and affected by residual Exxon Valdez oil up to 20 years after the original spill (Esler et al. 2010). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Oil spills, for example those due to tanker collisions and groundings or platform accidents, can have huge adverse impacts on marine systems. The impact of an oil spill at sea depends on a number of factors, such as spill volume, type of oil spilled, weather conditions, and proximity to environmentally, economically, or socially sensitive areas. Oil spilled at sea threatens marine organisms, whole ecosystems, and economic resources in the immediate vicinity, such as fisheries, aquaculture, recreation, and tourism. Adequate response to any oil spill to minimize damage is therefore of great importance. The common response to an oil spill is to remove all visible oil from the water surface, either mechanically or by using chemicals to disperse the oil into the water column to biodegrade. This is not always the most suitable response to an oil spill, as the chemical application itself may also have adverse effects, or no response may be needed. In this article we discuss advantages and disadvantages of using chemical treatments to reduce the impact of an oil spill in relation to the conditions of the spill. The main characteristics of chemical treatment agents are discussed and presented within the context of a basic decision support scheme.
    Integrated Environmental Assessment and Management 04/2012; 8(2):231-41. DOI:10.1002/ieam.273 · 1.38 Impact Factor
Show more