TP2 Wildlife Toxicology
Ballroom F, Level 4
2:10 PM - 5:30 PM, Tuesday, 11 November 2003
Chair: McMurry, Scott ,
(265) Northern pocket gophers inhabiting the Anaconda Smelter Superfund Site as sentinel species of environmental metals exposure and effects.
Reynolds, K1, McFarland, C1, Schwarz, M2, Mcbride , T1, Strauss , R3, Hooper , M1, Cobb , G1, McMurry , S1, 1 The Institute of Environmental and Human Health / Texas Tech University, Lubbock, TX, USA2 U. S. Fish and Wildlife Service, Grand Island, NE, USA3 Department of Biology / Texas Tech University, Lubbock, TX, USA
ABSTRACT- The northern pocket gopher (Thomomyes talpoides) has the widest distribution among all pocket gophers in North America, and their fossorial behavior makes them an excellent sentinel species for studying wildlife exposure to soil-bound contaminants. Over two years, we live-trapped fifty-three northern pocket gophers inhabiting areas of the Anaconda Smelter Superfund Site contaminated with a gradient of heavy metals and arsenic. Concentrations of As, Cd, Pb, Cu, and Zn were determined in blood, kidney, liver, carcass, and stomach contents to quantify exposure. Health effects endpoints included measurements of hematological parameters, ALAD enzyme activity, and liver and kidney porphyrin profiles. All heavy metals and arsenic were detected in all tissues analyzed for residues. Concentration of lead in soils collected from gopher burrows ranged from 17.30 to 1404 ppm and a positive significant (p = 0.0030) relationship existed between concentration of soil lead and concentration of lead in gopher livers. Among the health effects endpoints, we observed a significant (r2 = 0.48; p = 0.0120) inverse relationship between concentration of lead in the blood and ALAD enzyme activity. Although many species of small mammals have been used as sentinel species on metals-contaminated hazardous waste sites, to our knowledge, this is the first report of metal contaminant levels in northern pocket gophers. From the results of this study, we recommend the northern pocket gopher as a good model for evaluating environmental metal exposure and effects. Funded by NIH ES04696, USEPA, USFWS and The ARCS Foundation.
Key words: heavy metals, pocket gopher, ALAD, tissue residues