Effects of bioaccumulation of PCBS on biodiversity and distribution of fish in two creeks in east Tennessee (USA)

The Oak Ridge Reservation, established in Tennessee during World War II as a research, development and process facilities support for the Manhattan Pr oject, released large quantities of organic, inorganic and radionuclear con taminants into the environment. Their effects are particularly evident in a quatic ecosystems, as chemical concentrations in water, and as a disease in biodiversity and species richness. East Fork Poplar Creek and its tributar y, Bear Creek flow inside the Reservation and have highly degraded natural habitats, unsatisfactory water quality and impoverished biota. PCB concentr ations exceed recommended criteria for aquatic life safety and appear as a primary cause of environment degradation and reduced species richness. An u ptake model, FGETS (Food and Gill Exchange of Toxic Substances) was used to analyse fish biodiversity and distribution in the two streams in relation to bioaccumulation of PCB congeners 1254 and 1260. Bioaccumulation of the t wo polychlorinated biphenyls was estimated in four different species of fis h common in Tennessee rivers and streams: Catostomus commersoni, Lepomis ma crochirus, Cyprinus carpio and Micropterus salmoides to integrate the avail able set of data and to evaluate the entity of human impact on these escosy stems.