The following abstract represents the typical size received. It is 200 words long, or 1,205 characters, including spaces.
Toxaphene was used as a pesticide on crops and an insecticide on livestock. Toxaphene levels in biota from the Great Lakes are variable among lakes, ranging from 0.25 mg/g in Lake Erie in 1992/1994 to 4.9 mg/g in Lake Superior for lake trout (Salvelinus namaycush; Glassmeyer et al. 1997). This variation is thought to be due to local sources and physical processes within the lake which could affect toxaphene residence time within the water column (Swackhamer et al. 1999). To examine the transfer of toxaphene through benthic and pelagic components, the food web of Grand Traverse Bay, Lake Michigan was sampled from April 1997 - September 1998, and analyzed for toxaphene. Concentrations ranged from a low of 1 ng/g ww in mysid shrimp (Mysidopsis bahia) to a high of 1,200 ng/g ww in burbot (Lota lota). Using stable isotope analysis to examine trophic transfer, we found that the toxaphene concentrations are not correlated to the dN15 isotope levels in the food web (r2 = 0.26). However, when species are separated into benthic and pelagic components, a much higher correlation is found, and the regression coefficient increases to 0.44 in the benthic food chain, and 0.64 in the pelagic food chain.
