Keywords: industrial effluents, water pollution, environmental impact, anthropogenic, effluent discharge, river pollution, surface water, sediments, Nigeria
Pollution assessment of the impact of industrial effluents on the qualities of surface water and sediments of River Ona in Ibadan, Oyo state, Nigeria
River Ona, a major river in Ibadan, into which industries discharge their effluents, was studied to assess the impact of the industrial discharge. The mean levels for some parameters gave evidence of pollution. The mean values for DO (4.9 ± 0.3 mg/l), COD (54.5 ± 0.5 mg/l), PO43− (0.47 ± 0.09 mg/l), SO42− (20.65 ± 0.85 mg/l) were reported for the upstream region, while the downstream mean values for same parameters gave 3.72 ± 0.37 mg/l, 211.20 ± 59.6 mg/l, 1.06 ± 0.20 mg/l and 23.62 ± 3.20 mg/l, respectively. The effluent was also analysed, and the results obtained confirmed that the effluent was not the only source of pollutants in the river.