Health risk assessment of 'tiger prawn seed' collectors exposed to heavy metal pollution in the conserved mangrove forest of Indian Sundarbans: A socio-environmental perspective

Heavy metals contamination from anthropogenic sources in waterways of conserved mangrove ecosystem (Indian Sundarbans) poses serious health hazard to the economically marginalized 'tiger prawn seed' (TPS) collectors. Principal component analysis identifies Pb, Ni and Cd as anthropogenic pollutant in Indian Sundarbans. It is observed that Cu, Fe and Zn concentration increases in monsoon, whereas concentration of Cd and Pb decreases in comparison to pre-monsoon levels at all seven fishing villages. Economic status has been assessed using Wealth Rank Tool, which indicates 16-71% of population is in acute economic stress conditions and 5-70% of populations engaged in unsustainable TPS collection for their livelihood. Focus group discussion shows that collectors are exposed (exposure time (ET)) to contaminated water for 3-7 h/d, and lifetime exposure (exposure duration (ED)) varies from 5 to 20 yr. Using site-specific ET and ED results, cumulative hazard quotient (HQ) dermal is estimated to be higher in female than in male. HQ varies from medium (>= 1 to < 4) to high (> 4) due to Cd pollution (0.1-0.26 mg L-1). The study suggests that promoting alternative sustainable livelihood through group-based organizations (poultry, organic farming, entrepreneurship and transport) could be an effective solution to this problem.