PW08 Aquatic Ecotoxicology II
Exhibit Hall
8:00 AM - Wednesday
(PW117) Mercury concentrations in gonad, liver, and muscle of white sturgeon, Acipenser transmontanus, in the lower Columbia River.
Gundersen, D1, Kushner, L1, Fink, A1, Schreck, C2, Feist, G2, Webb, M2, Foster, E3, Fitzpatrick, M3, 1 Pacific University Environmental Science Program, Forest Grove, Oregon, USA2 Oregon Cooperative Fishery Research Unit, Department of Fisheries & Wildlife, Oregon State University, Corvallis, Oregon, USA3 Department of Environmental Quality, Portland, Oregon, USA
ABSTRACT- This study determined the partitioning of mercury in liver, gonad, and cheek muscle of juvenile white sturgeon captured from 4 sites in the lower Columbia River. The relationship between tissue mercury concentrations and various physiological parameters were assessed. Condition factor (CF) and gonadosomatic index (GSI) were measured for all fish. Blood plasma samples were analyzed for 17-b estradiol (E2), testosterone (T), and 11-ketotestosterone (KT), using RIA. Sturgeon tissues were analyzed for total mercury using cold vapor atomic fluorescence (CVAF). Mean tissue mercury concentrations were higher in muscle compared to liver and gonad. Mean liver mercury content of Bonneville Reservoir sturgeon was higher than mean mercury concentrations for other tissues analyzed from the other 3 sites. The concentrations of mercury in the muscle and fillet of the only adult female analyzed, exceeded all action limits (muscle) and state and EPA action limits (fillet) for mercury in edible fish tissues. Significant negative correlations between plasma androgens and muscle mercury content and plasma estradiol-17b and liver mercury content were found. A significant positive linear relationship between sturgeon age and liver mercury concentration was evident. Significant negative correlations between condition factor and gonad and liver mercury content were found as well as a reduced GSI in immature males with elevated gonad mercury content. These results suggest that methylmercury may have an affect on the reproductive potential of white sturgeon.
Key words: Sturgeon, Mercury, Biomarkers