Biomarkers: the application of a suite of techniques to determine environmental quality

Indigenous and deployed mussels, Mytilus edulis, were examined at four sites on the Tees Estuary, in northeast England. Two of the sites had recently been exposed to an acute effluent discharge. Mussels (obtained from Whitsand Bay, a reference site in southwest England) were deployed at the sites for 24 h; water samples and indigenous mussels were also collected. Tests for haemocyte lysosomal stability and heart rate activity were conducted on adult mussels. Adult mussels were sacrificed and preserved for histopathology. Indigenous and deployed mussels were induced to spawn and the resultant larvae examined for abnormalities. Larvae (from Whitsand Bay adult mussels) were also exposed to the sampled water. The lysosomal stability, heart rate activity, histopathology, and larval bioassays showed significant differences between sites. A relationship between these techniques was observed. These results are encouraging for the continued application of these biomarkers as rapid indicators of environmental quality.