DETERMINATION OF SOME SELECTED HEAVY METALS(Cu, Cd, Cr, Pb,and Ni) SEDIMENT AND TILAPIA(OREOCHROMISNILOTICUS) FISH SPECIES FROM CHAMO LAKE, SOUTHERN ETHIOPIA

Abstract

In the present study, some heavy metal Cd, Cu, Ni, Pb and Cr were determined in sediment and some tissue of tilapia (Oreochromisniloticus) fish from Chamo lake which is an important water source for irrigation. Heavy metal levels in sediment and fish sample were analyzed byAtomic absorption spectrophotometry (AAS). The result of the heavey metal (Cd,Cu,Cr,Pb and Ni) levels in the sediment were compared with national and international standard sediment quality guidelines as well as literature data reported of the lake. The analysis of heavy metals in sediment indicated that among the five heavy metals were present.the result showed that highest Cd concentration (6.07mg/kg) Cd wasrecorded. followed by Cu,Pb, Ni, Cr,and Cu. The heavy metals concentration was found to decrease sequence of Tilapia(Oreochromisniloticus)fish tissue of gill>liver>muscle. In general the heavy metals concentration in the fish tissue decreased insequence for liver [as Cu>Cd>Cr>Ni>Pb,for gill as Cd>Cu>Ni>Cr>Pb, for muscle as Cu>Cd>Cr>Ni>Pb]. The result showed the concentration of Cd, Cu, Cr, Ni and Pb in muscle tissue of tilapia(Oreochromisniloticus) fish from lake chamo were below the value of WHO. While the concentration of Cr in muscle tissue of fish from lake chamo was higher than WHO. Therefore the muscle part of tilapia fish is safe interim of Cd, Cu, Ni,and Pb. But interim of Cr bad or may cause hazard tt the fish. So that the people should not be consume the fish in this area.due to that the high intake of heavy mtals in our body can case bad impact towards health.