Udiba Udiba U., Inuwa Bashir, 2Saminu Falalu, Bello Garko, Kabir A. Fagge and Zakariyya Ahmad
Levels of contaminants in fish are of particular interest because of the potential risk to humans who consume them. Clarias gariepinus were obtained from River Galma, River Kubanni and some Fish farms in Zaria. The head, liver, gills and muscles were carefully dissected for the determination of heavy metals. Iron, cobalt and manganese were determined using Schemadzu, Atomic Absorption Spectrophotometer (model 6800, Japan) after wet digestion. The results revealed that, Clarias gariepinus liver tissues contained the highest concentration of iron (63%) and cobalt (73%) while the highest concentration of manganese was recorded in gills tissues (36%). Fish muscles appeared to be the least preferred site for the bioaccumulation of the three metals as the lowest concentrations (6%) were detected in this tissue. The order of detection was liver > gills > heads = muscles for iron, liver > gills > heads > muscles for cobalt and gills > heads > liver > muscles for manganese. The mean concentrations of iron and manganese measured in Clarias gariepinus from Rivier Galma and River Kubanni were found to be above the Food and Agricultural Organization (FAO) and US EPA guidelines for consumed food and fish. These findings indicate possible sediment and/or surface water contamination by iron and manganese in River Galma and River Kubanni and that consumption of Clarias gariepinus from the two rivers could pose serious health risk. Implications of findings to public health are fully discussed.
