BIO-ACCUMULATION OF HEAVY METALS AND ASSESSMENT OF HUMAN HEALTH RISKS ASSOCIATED WITH THE CONSUMPTION OF CALLINECTES AMNICOLA AND PENAEUS MONODON FROM ESCRAVOS ESTUARY, DELTA STATE, NIGERIA

This study examined Ni and Pb concentrations in sediment, Callinectes amnicola, and Penaeus monodon from Escravos Estuary (EE), Delta State, Nigeria. The estuary was divided into three stations (X, Y, Z) based on fish landing sites, while seasonal sampling was dry (January to March) and wet (April to June) seasons in 2025. Sediment, C. amnicola, and P. monodon were collected for six months and analyzed for nickel, lead, and health risk indices—Target Hazard Quotient (THQ), and Hazard Index (HI)—using standard procedures. Data were subjected to descriptive and inferential statistics at 5% significance. Results revealed significant spatial and seasonal concentrations of nickel in sediments, which peaked at station Y (0.06±0.02 mg/kg) and were lowest at X (0.03±0.02 mg/kg). In contrast, seasonal values ranged from 0.03±0.02 to 0.05±0.01 mg/kg. Lead was highest at X (0.04±0.02 mg/kg) and lowest at Y (0.04±0.01 mg/kg), with seasonal values 0.02±0.01–0.03±0.01 mg/kg. In C. amnicola, Ni-THQ was 0.0758, HI 0.6754, while P. monodon showed Ni-THQ 0.0249, HI 0.6710. Rising Ni and Pb levels, alongside elevated risk indices, indicate threats to species abundance and human consumers. Regular monitoring of EE is recommended for sustainable fisheries and public health protection.