Assessment of Heavy Metal Pollution in Water, Shrimps and Sediments of Some Selected Water Bodies in Ondo State.

Abstrakt

The introduction of heavy metals into the aquatic ecosystems through the extensive exploitation and exploration of crude oil in Nigeria has become the subject of environmental risks. This study was carried out to assess the physico-chemical parameters, and concentrations of heavy metals (Mn, Cu, Pb, Fe, Zn, and Cd) in water, shrimps and sediments from the coastal waters in Ondo State, Nigeria. The result of the water samples show that electrical conductivity and dissolved oxygen varied from (2.68±0.89 μS/cm and 7.79±0.49mg/l) in Idiogba to (4.52±4.16 μS/cm and 8.2±1.16mg/l) in Bijimi respectively. The values were not significantly different across the stations. The heavy metals with the highest concentrations in water, Nematopalaemon hastatus, Farfantepenaeus notialis and sediments were Mn (2.82±1.46), Zn (7.511±0.190), Zn (7.011±0.165) and Mn (18.48±0.90) respectively. Metals in water samples, Zn, Cd, Pb, and Cu in shrimps were within the WHO and FEPA limits, while that of Mn and Fe in shrimps, and metals in sediments were above. The concentration of heavy metals in the sediments was higher than in water and shrimps. Therefore, close monitoring of the environment is recommended with a view to sustain the biodiversity of the ecosystem.