Assessment of Heavy Metal Loadings of Water and Sediment of River Enumabia in Orokam, Benue State, Nigeria

Abstract

Enumabia being the only surviving river in Orokam community gave us the concern to assess the concentration of heavy metals in water and sediment in the river. 20 samples of water and Sediment were taken from four (4) different points 20 meters apart and analysed for heavy metals by the use of AA-700 Dual Atomizer Atomic Absorption Spectrophotometer in Energy Research Centre, University of Nigeria, Nsukka. In water, the concentration of Fe ranges from 0.7669 to 0.9214 mg/l, Pb ranges from 1.3300 to 1.7210 mg/l, As ranges from 0.9032 to 2.0120 mg/l, and there was no concentration of Hg, Cr and Al. The concentration of metals in the water samples are at the range of permissible limit set by World Health Organization (WHO) except Pb, and As that are fairly higher than the permissible limit. In sediment, the concentration of Fe ranges from 128.8812 to 113.9563 mg/l, Pb ranges from 0.2500 to 0.9520 mg/l, Cr ranges from 0.1240 to 0.6676 mg/l, Al ranges from 10.0000 to 16.0000 mg/l, As ranges from 0.0000 to 1.1240 mg/l, Cu ranges from 0.2420 to 0.8490 mg/l and there was no concentration of Hg. The concentration of Fe, Pb, Cr and As in the sediment exceeded the standards set by WHO. This presence could be detrimental to plant, human being and aquatic life. Since there is fast accumulation of toxic and carcinogenic metals present in the water and sediment samples collected from Enumabia River in Orokam there is need for a follow up study to determine how the human and aquatic lives have been affected.