Biomarker Assessment of Environmental Contamination: In-Situ Studies with Freshwater Bivalves

Abstract

Bivalves are effective pollution biomonitors in marine and freshwater environments because of their ability to bioconcentrate many environmental pollutants to levels that greatly exceed those found in water and sediments. However, most research efforts have focused on monitoring chemical accumulation by bivalves, and have not examined the toxic effects of accumulation or exposure to toxic chemicals. In addition, different phases of the mussel life cycle have been sparingly employed for toxicity evaluations. Our research has focused on developing biomarker assays for adult and juvenile bivalves, primarily DNA strand breakage and the nonspecific biomarkers, growth and condition index. Herein we describe a study using these biomarkers in juvenile and adult Corbicula fluminea exposed in a stream contaminated with urban and industrial runoff. Our ultimate goal is to develop and validate appropriate biomarkers for use in assessment of exposure and effects for risk assessments.