|SREL Reprint #2415|
Contaminant Exposure and Biomarker Responses in Spectacled Eiders (Somateria fischeri) from St. Lawrence Island, Alaska
K. A. Trust,1 K. T. Rummel,2 A. M. Scheuhammer,3 I. L. Brisbin, Jr.,4 M. J. Hooper2
Fish and Wildlife Service, Ecological Services, 605 West 4th Ave., Room G62,
Anchorage, Alaska 99501, USA
Received: 17 March 1999/Accepted: 7 June 1999
Abstract: Effects of chemical contaminant exposure may be contributing to the decline of spectacled eiders (Somateria fischeri) nesting in coastal areas of western Alaska. We evaluated chemical exposure and potential effects in 20 male eiders collected near St. Lawrence Island, Alaska. Analytes included metals, trace elements, chlorinated organics, and 137Cesium (137Cs). Effects of contaminant exposure were evaluated using histopathology and biochemical measures of porphyrin profiles, cytochrome P450 activities, and metallothionein (MT) concentrations. Copper, cadmium, and selenium concentrations were elevated in spectacled eiders when compared to literature values for other marine birds. Only a few samples had trace concentrations of chlorinated organic compounds. Muscle 137CS levels were all below the average minimum quantifiable concentration of 0.079 Bq/g. No histopathological lesions were associated with elevated contaminant concentrations in liver, kidney, or testes. Protoporphyrin was found in highest concentration in both the liver and kidneys, followed by coproporphyrin and uroporphyrin, respectively. Hepatic uroporphyrin concentrations correlated significantly to hepatic arsenic concentrations. Mean activities of hepatic EROD, MROD, BROD, and PROD were consistent with other avian species. Comparisons of cadmiun VMT ratios from this study to published literature ratios in seven marine avian species suggest that, although adult male spectacled eiders have elevated liver concentrations of certain MT-inducing metals, their MT concentrations are not as strongly induced as would be predicted based on literature values. Despite elevated metal concentrations, the apparent good health of the St. Lawrence Island birds suggests that should these contaminants be a factor in population declines, they likely act by decreasing fecundity or survival of young rather than via direct health impacts on adult male spectacled eiders.
SREL Reprint #2415
Trust, K.A., K.T. Rummel, A.M. Scheuhammer, I.L. Brisbin, Jr., and M.J. Hooper. 2000. Contaminant exposure and biomarker responses in spectacled eiders (Somateria fischeri) from St. Lawrence Island, Alaska. Archives of Environmental Contamination and Toxicology 38:107-113.