MOLLUSCS AS BIOMONITORS OF HEAVY METAL POLLUTION: A REVIEW

Abstract

Heavy metal pollution is a worldwide incident with serious consequences. Heavy metals are continuously discharged into the aquatic ecosystem and potentially accumulate in water as well as sediments. This affects the health of the aquatic organisms and the accumulated heavy metals also get transferred to human beings through the food chain. Molluscs are considered as a potential biomonitor for heavy metal contamination in the marine ecosystems due to their wide geographical distribution, sedentary and sessile lifestyle. Being filter-feeders they bioaccumulate several contaminants in their tissues at a much greater rate. Thus, the metal body burden in molluscs might mirror the concentrations of metals in water and sediment giving a sign about the quality of the surrounding environment. This review will provide a general overview of the studies that have used molluscs in aquatic ecosystems influenced by heavy metals as sentinel bioindicators. It will also give some recommendations to control heavy metal pollution and protect the aquatic ecosystem and human beings.