PAPER TITLE :BIOACCUMULATION OF HEAVYMETALS IN SOME FRESHWATER FISHES FROM OGBESE RIVER, OGBESE, ONDO STATE

FUTA JOURNAL OF RESEARCH IN SCIENCE | VOLUME 13 NUMBER 2 2017

Paper Details

  • Author(s) : *M. O. Ashamo and A. Raheem
  • Abstract:

The heavy metal concentrations in the organs of freshwater fishes and sediments from Ogbese River, Ogbese, Ondo State, Nigeria was studied. The heavy metals included Chromium (Cr), Cadmium (Cd), Nickel (Ni), Lead (Pb), Copper (Cu), Zinc (Zn), Iron (Fe) and Manganese (Mn). The freshwater fishes studied were Clarias gariepinus (Burchell, 1822), Parachanna obscura (Teugels and Daget, 1984) and Oreochromis niloticus (Linnaeus, 1758). The different heavy metal concentrations in the sediments as well as liver and flesh of the fish species were determined using Buck 200 Atomic Absoption Spectrophotometer (AAS). The increasing order of heavy metal concentration in the sediment and fish were Cd<Pb<Cr<Ni<Cu<Mn<Zn<Fe. The mean concentration of each heavy metal was higher in the sediment than those of the fish (for example lead concentrations of 0.15 ± 0.01 mg/kg and 0.03 ±0.001 mg/kg in sediment and in fish respectively); also, in the liver than in the flesh of each fish species (for example manganese concentrations of 9.77 ± 0.32 mg/kg in the liver and 8.33±0.34 mg/kg in the flesh). Bioaccumulation factor (BAF) of P. obscura was higher than that of O. niloticus for all of the metals except manganese. Also, BAF of Cd (0.18) and Cr (0.29) were same for C. gariepinus and O. niloticus while Pb, Ni, Fe, Mn, Cu and Zn showed lesser bioaccumulation in C. gariepinus as compared to O. niloticus. The results showed that the total mean concentrations of Cr (0.37 ± 0.02 mg/kg), Fe (159.99 ± 2.00 mg/kg), Mn (8.33 ± 0.34 mg/kg) and Cu (5.73±0.35) in the different fish species exceeded WHO permissible limits of 0.15 mg/kg, 123.5 mg/kg, 0.5 mg/kg and 3.0 mg/kg respectively. In view of the toxicity associated with heavy metal accumulation, safe disposals of domestic sewage and industrial effluents as well as enforcement of enacted laws to protect our environment are therefore advocated.
Keywords: Heavy metal, WHO, Sediment, Ogbese, Concentration.