The presence of some heavy metals in the water, sediments and Sarotherodon galileaus fish in Ilo-Idimu River, Ogun State, Nigeria

Abstract

The Ilo-Idimu river is situated in the heavily industrialised Ota Town, Ogun State, Nigeria, with industries empting their wastes or part of their wastes into the river. The community use the water of the river for domestic purposes such as cooking, drinking, bathing and washing. Iron (Fe) was the most abundant heavy metal amongst the four [Copper (Cu), Iron (Fe), Zinc (Zn) and Lead (Pb)] heavy metals tested for in the Ilo-Idimu River. Though, the levels of lead was more in the littoral midstream (Lit B) and benthic upstream and downstream (Bent A and C) 1.60, 1.40 and 1.30 mg/l respectively. The fish samples of Sarotherodon galileaus tested for the four heavy metals showed that lead (Pb) was present only in the gut of the fish. For the other heavy metals the trend are Cu > Zn > Fe in the scale, in the flesh of the fish Cu > Fe > Zn, while Fe > Cu > Zn in the gills and gut of the fish. The levels of the heavy metals tested in the water and fish samples were lower than the WHO standards therefore, there is no immediate threat to the biodiversity of the aquatic species in the river and to the health of the community using the water for various domestic uses.