PAH-metabolizing enzymes in whole mussels as biochemical tests for chemical pollution monitoring

Enzyme activities related to PAH metabolism, benzo(a)pyrene hydroxylase (B(a)PH), epoxide hydrolase (EH) and glutathione S-transferase (GST), in subcellular preparations from whole mussels Mytilus edulis, were assayed during the GEEP Workshop as possible biochemical tests for pollution monitoring. No response was observed along a field pollution gradient in Langesundfjord, owing to the variability within each biochemical measurement and to the limted number of samples/ animals assayed per site. In mesocosm exposures to a diesel oil and copper mixture, inductions of B(a)PH and EH activities were related to some extent to the PAH gradent. These specific biochemical variables were more sensitive than a general biochemical variable related to the physiological state of the animal, the cytosolic glutathione content.