Assessment of Water Quality and Heavy Metal levels of Fish Species in Oguta Lake, Imo State Nigeria.

Abstract

The level of accumulation of some heavy metals: Iron, Copper, Lead, Nickel, Mercury, Chromium, Cadmium and Arsenic in the full body of some local fishes (Mud fish, Tilapia fish, Cat fish and Ifuru fish) and impact of some physicochemical variables on the water quality of Oguta Lake was investigated. The study was carried out in the month of June, 2013 and water sampling carried out in June and September, 2013; and standard methods adopted for their analysis. The accumulation of analysed metals was specie related as their mean concentrations were higher in mud fish and tilapia fish and lowest in cat fish. Lead, mercury, arsenic were not detected in all fishes, while chromium was absent in the studied species except in mud fish. The levels of Turbidity, Nitrate, Total Coliform, Iron, Cadmium and Nickel exceeded the maximum permissible limit of Nigerian Industrial Standard and as such the raw water cannot be used in this form for domestic purposes without treatment. However, the level of nitrate-nitrogen detected shows that the water is safe as nitrification has occurred and pollution could not have been recent. The water body will sustain aquatic life taking cognizance of the values of DO and BOD which was within permissible limits. Safe disposals of domestic sewage and industrial effluents as well as enforcement of laws enacted to protect our environment are therefore recommended.

KEY WORDS: Oguta lake, Heavy Metals, Physico chemical, Fish