EFFECTS OF LINEAR ALKYLBENZENE SULFONATE (LAS) AND CADMIUM IN THE DIGESTIVE GLAND OF MUSSEL, MYTILUS SP

A laboratory study was carried out exposing mussels (Mytilus sp.) to l inear alkylbenzene sulphonate (LAS) (6 mg litre(-1)), Cd (0.05 mg litr e(-1)) and LAS plus Cd at the same concentrations. The aim was to asse ss the use of several histopathological and biochemical indices as pot ential biomarkers of the impact of these xenobiotics in the digestive gland of molluscs. Treated mussels actively accumulated Cd in the dige stive gland compared with controls (p less than or equal to 0.01), the highest levels occurring after 30 days of exposure in the group treat ed with Cd plus LAS. Among several histological alterations screened i n digestive gland tissues the thickness of digestive tubules in Cd tre ated animals decreased more markedly (p less than or equal to 0.01) th an in LAS exposed mussels. As for biochemical parameters, the investig ated antioxidant enzyme activities, superoxide dismutase (SOD), catala se, DT-diaphorase and glutathione peroxidase (GPX) did not show any si gnificant induction due to these xenobiotics. However, a slight decrea se of the antioxidant defences of the animals was detected after 30 da ys of exposure to contaminants.