Heavy Metals in Estuarine Finfish and Crustaceans and Their Associated Health Risks in the Western Hooghly Estuary, Indian Sundarbans

Mangroves are highly productive ecosystems that provide important social, economic, and environmental benefits. However, they are increasingly exposed to various contaminants, including heavy metals. The presence of heavy metals in such ecosystems can pose a serious threat to marine and aquatic life, including fish and crustaceans. Fish (Lates calcarifer, Liza parsia and Mystus gulio) and crustaceans (Penaeus monodon and Scylla serrata) were collected from local fishermen in Nayachar, West Bengal, in the Indian Sundarbans. Fe, Zn, Cu, Ni, Pb, Cr, Cd and As, concentrations were measured in the edible muscle tissues of these species using Atomic Absorption Spectroscopy (AAS). The concentration of heavy metals in the edible muscle tissues were observed in the following descending order: Fe > Zn > Cu > Pb > Ni > Cr > Cd > As. Results show a potential health risk from Pb both in terms of target hazard quotient (THQ) and provisional tolerable weekly intake (PTWI) for Lates calcarifer, Liza parsia and Mystus gulio. However, the consumption of these species didn’t pose a serious health risk with respect to other measured heavy metals as both THQ and PTWI were within the established and/or recommended limits. Long-term exposure to these fish species could pose a significant toxicity risk to individuals who consume them regularly. Regular monitoring, identification of contamination sources and treatment are crucial to reduce any potential health risks to the local population and other consumers, as the Sundarbans is a major fish producing area in the state of West Bengal, India.