Seasonal Dynamics of Trace Metals in Marine Sediment Influenced Bioaccumulation in Giant Tiger Prawn (Penaeus monodon) from Rivers State, Nigeria

This study investigated the temporal bioaccumulation of trace metals (Cd, Pb, Cr, As, Zn, Cu, Ni) in the Giant Tiger Prawn (Penaeus monodon) sourced from Bille Creek, Degema LGA, Rivers State, Nigeria, over a six-month duration from December 2024 to May 2025. Monthly, three sites adjacent to oil facilities and one control site located 2 km away were utilised to collect three samples of prawns and sediments. We conducted in situ measurements of physicochemical parameters, including pH, electrical conductivity, dissolved oxygen, biological oxygen demand, temperature, and salinity. Trace metals were examined in prawn tissues and soil samples utilising Atomic Absorption Spectrophotometry (AAS). The findings suggested a distinct hierarchy of metals in prawn tissues: Zn > Cu > Pb > Ni > Cr > Cd > As. Copper (Cu) attained a maximum concentration of 10.451 ± 1.023 mg/kg in March, while zinc (Zn) reached a peak concentration of 10.67 ± 0.946 mg/kg in December. The damp season commenced in December, as lead (Pb) and cadmium (Cd) concentrations increased to elevated levels. In April, arsenic (As) exhibited the greatest Bioaccumulation Factor (BAF) of 1.222, indicating its increased availability to biota. The research demonstrated that seasonal variations in trace metals, resulting from runoff and sediment resuspension, significantly influenced bioaccumulation in Penaeus monodon. The analysis reemphasizes the necessity of both seasonal pollution control and rigorous basin and consumption advisory as tools for engaging in the unfortunate exposure of the environmental and human population to the dangers of heavy metal poisoning in the Niger Delta.