Determination of pollution index of benin river flowing through oghara industrial site of ethiope west l.g.a, nigeria

The present study was done to ascertain the pollution index of Benin River flowing through the industrial site of Oghara town for the assessment of heavy metals’ concentrations in soil and water samples. The description of the study area was enhanced by means of a geographic positioning system (GPS) and geographic information system (GIS) devices of the designated sites (A, B, C) with specific distances of 100, 200 and 300 m from the industrial site (labelled D). In each case for soil and water samples whose pHs were determined, a total of twelve samples with three samples at the respective sites were collected for the evaluation of six heavy metals (Zn, Cu, Mn, Cd, Cr and Pb) using atomic absorption spectrophotometer. Although the correlation study showed no marked significant difference (p>0.05) among the concentrations of heavy metals obtained from the designated sites, the results of pollution indices of heavy metals in soil (A-0.26, B-0.39, C-0.39 and D-0.44) and water (A-0.11, B-0.09, C-0.07 and D-0.09) samples were less than a unit, and the quality grades of the samples were considered unpolluted and may be safe for domestic and agricultural purposes.