Heavy metal pollution in the lower gangetic mangrove ecosystem

TLDR: In this article, the level of selective heavy metals (zinc, copper, and lead) in the water and muscle of a commercially important shellfish species (Penaeus monodon, commonly known as tiger prawn) collected from two sectors (western and central) in Indian Sundarbans.

Abstract: The Gangetic delta, sustaining the Sundarbans mangrove forest at the apex of the Bay of Bengal is recognized as one of the most diversified and productive ecosystems in the Indian subcontinent. The deltaic lobe is unique for its wilderness, mangrove gene pool and tiger habitat. However, due to intense industrial activities in the upstream zone, and several anthropogenic factors, the aquatic phase in the western part of the deltaic complex is exposed to pollution from domestic sewage and industrial effluents leading to serious impacts on biota. The presence of Haldia port-cum-industrial complex in the upstream region of the lower Gangetic delta (adjacent to western sector of Indian Sundarbans) has accelerated the pollution problem to a much greater dimension. The organic and inorganic wastes released from industries and urban units contain substantial concentrations of heavy metals. The present article aims to highlight the level of selective heavy metals (zinc, copper, and lead) in the water and muscle of a commercially important shellfish species (Penaeus monodon, commonly known as tiger prawn) collected from two sectors (western and central) in the Indian Sundarbans. Heavy metals are accumulated in the prawn muscle in the following order – zinc > copper > lead – which is similar to the order in the ambient estuarine water. Significant spatial variations of heavy metal concentrations in estuarine water and prawn muscle were observed between the selected sectors, which reflect the adverse impact of intense industrialization, unplanned tourism, and rapid urbanization on the mangrove ecosystem and its biotic community, particularly in the western Indian Sundarbans.