C. D. NWANE, V.C. NWOYE, J.N. AFIUKWA AND J. E. EY0
Abstract
Studies were carried out between June 2006 and May 2007 to evaluate the concentration of six heavy metals (iron, zinc, copper, lead, manganese and chromium) by atomic absorption spectrophotometer in the gills and muscles of six commercial fresh water fish species Mormyrus none rume (Vallenciennes, 1847), Mormyrus tapirus(Pappenheim,1905), Marcusenius cyprinoides (Linnaeus,1758), Labeo coubie (Ruppell, 1832), Hepsetus odoe (Bioch,1794) arcd Protopterus allItectens annectens (Ovven,1839) from Anambra River South East Nigeria. The gills on the average absorbed more metals in all the fishes studied when compared with the muscles except in Hepsetus odoe (Bloch,1794). The order of heavy metal concentration in the fish species was Fe>Zn>Cu>Mn>Cr>Pb. While the concentration of Fe (except in the gills of M. rume rume(Vallenciennes,1847), Zn and Ph in the muscles and gills of all the six fish species studied were within the WHO and FEPA prescribed limits for food fish, that of Cu, Mn and Cr were above the prescribed limits thus indicating contamination of these fish species by these metals. The toxicological implications ot this finding in relation to aquatic ecosystem and human health are discussed.