Alterations in enzyme activities in hepatopancreas, gill and adductor muscles of intertidal clam, Gafrarium divaricatum, exposed chronically to xylene, benzene and gear oil-WSF

Gafrarium divaricatum were exposed to sublethal concentration of xylene (4.25 and 8.50 mg/l), benzene (4.35 and 8.70 mg/l) and gear oil-WSF (1 and 2%) for 30 days. Alterations in activities of lactate dehydrogenase (LDH), acid phosphatase (ACP), alkaline phosphatase (ALP), aspartate aminotransferase (AAT), alanine aminotransferase (ALAT) and adenosine triphosphatase (ATPase) in hepatopancreas, gill and adductor muscles of the clams were recorded on day 4 and 30 which were found to be dose- as well as timedependent. Elevated LDH, AAT and ALAT activities in the tissues of experimental clams indicates an adaptation to anaerobic metabolism while reduced ACP and ALP activities suggest uncoupling of oxidative phosphorylation. Inhibition in ATPase activity might be the result of direct effect of the pollutants on membrane permeability causing dysfunction in coupling ionic and pH membrane potentials to ATP synthesis. Present study suggests that the clams resort to anaerobic mode of respiration under the pollution stress induced due to prolonged chronic exposure of xylene, benzene and gear oil-WSF.