PARENT SESSION

PM15 Biomarkers
Exhibit Hall
8:00 AM - Monday

(PM254) Watershed-scale application of biomarkers to assess ecosystem health.

Otter, R¹, Schreiber, E¹, van den Hurk, P¹, Klaine, S, ¹ Clemson University, Pendleton, SC, USA

ABSTRACT- Ecological risk assessment is a process that evaluates the likelihood that adverse effects may occur or are occurring as a result of exposure to one or more stressors (U.S. EPA, 1992). A watershed approach to ecological risk assessment provides a spatial assessment that includes exposure to multiple stressors. U.S. EPA has a framework for the assessment of watersheds that looks for cumulative impacts on an entire watershed instead of the historic site specific or point source approach. These watershed assessments rely on the use of water quality indicators such as contaminant concentrations in sediment, water, and fish tissue, the physical parameters of waterways, and macroinvertebrate or fish community indices. This study investigated the use of sub-lethal biochemical responses or biomarkers in fish as tools to evaluate watershed health. The Reedy River watershed (upstate South Carolina) is known to have high concentrations of Polyaromatic Aromatic Hydrocarbons (PAHs) and metals. Largemouth bass (Micropterus salmoides) were sampled from three river and three lake sites in a Reedy River, one lake site in the adjacent Saluda River (reference) and one lake site in adjacent watershed (reference). Metallothionein (MT) and 7-Ethoxyresorufin O-deethylase (EROD) induction and bile fluorescence (BF) assays were performed on each fish for metal exposure, PAH exposure, and PAH compounds and metabolites, respectively. PAH and metal analysis (Cu, Cd, Zn, and Pb) were performed on sediment samples from each sampling location to see if correlations between biomarkers and sediment samples were possible. Analysis of spatial changes in sediment samples and biomarkers were used as indicators as to whether the use of these specific biomarkers can be used as tools for watershed health assessments.

Key words: Largemouth bass, Biomarkers