Evidences gathered from the observations made on the structure of gills and digestive tubules of Perna indica clearly indicate that prolonged exposure to low levels of mercury, copper and cadmium individually or in concert would damage the tissues extensively. Even low levels of heavy metals when encountered by the mussel resulted in extensive disintegration of these sensitive tissues. Presence of more than one metal concomitantly resulted in greater damage of the tissues. Chronic exposure studies employing polluted media would help in establishing histopathological criteria to assess pollutional effects for incorporation in monitoring strategies.

Metal toxicity, histological aberrations, mussel, Perna indica