Journal Article

Bioaccumulation of Heavy Metals in Crab Species from The University of Lagos

Adebesin, O.A., Mairiga, J.P., Utom-obong, A., Saanu, A.I., Martins, V.N., & Ojo, S.G.

Abstract

Crab species (Cardiosoma armatum) collected from four different locations in the University of Lagos, were evaluated for suitability as a simple model for studying bioaccumulation and biomonitoring of heavy metals. Selected organs harvested from the collected samples were analyzed for antioxidant status, histopathology or concentrations of heavy metals. Results showed the highest accumulation of Lead (0.03mg/kg), Nickel (0.16mg/kg) and Cadmium (0.09mg/kg) in crab shells from UBA Park and Indomie Bridge, UBA Park and Highrise, respectively. Nickel and Lead levels were below detectable levels in the shells of all crabs obtained from Lagoon front locations in the study area. All (Pb, Ni & Cd) analyzed heavy metals were accumulated in the shells of crab species collected at Indomie Bridge, Highrise and UBA Park. Based on these findings, the abundance of the heavy metals in the study area was arranged in the order Pb> Cd > Ni. Water pH (4.90) value at Lagoon Front exceeded recommended values by Lagos State Environmental Protection Agency (LASEPA). Nitrate levels at all locations were below the recommended level while the concentration of Sulphate, generally exceeded recommended limit. The highest concentration of Biological Oxygen Demand (BOD) of 88 ppm was recorded at Indomie Bridge, at 1: 2 BOD (Biological Oxygen Demand) to COD (Chemical Oxygen Demand) ratio. The concentration of heavy metals in both soil and water samples was in the order of Ni = Pd> Cd. Based on these findings, continuous monitoring of the concentration of heavy metals in soil and water relative to accumulations in the tissue of (Cardiosoma armatum) species as a biomarker is recommended.

Download pdf