Heavy metals concentration in different organs of tilapia fish (Oreochromis niloticus) from selected areas of Bangi, Selangor, Malaysia

The present study was aimed at investigating the six heavy metals: Pb, Cd, Cr, Cu, Ni and Zn measured in the liver, gills and muscles of tilapia fish (Oreochromis niloticus) which was collected from five locations around Bangi area, Selangor, Malaysia. The sites included Culture Pond A, Culture Pond B, Langat River, Cempaka Lake and Engineering Lake. The results show that in general, the highest heavy metal concentrations were detected in the liver followed by the gill and the muscle. The heavy metal concentration in the tissues varied significantly depending upon the locations from where the fish was collected. In the liver, the highest Pb was detected in the Langat River (4.8 +/- 0.84 mu g/g dry weight) followed by that of Engineering Lake (3.28 +/- 1.15 mu g/g). Copper and Ni levels were observed as the highest in the fish collected from Cempaka Lake with value of 449 +/- 37.7 and 20.9 +/- 5.7 mu g/g, respectively. For Cd, the highest level was detected in the fish from Engineering Lake (0.70 +/- 0.17 mu g/g), while the highest values of Zn was recorded in those from the Langat River (143 +/- 9.8 mu g/g). The metal accumulation in the liver of fish was found to be quite high in comparison to the gills and muscles (edible part). However, the concentrations of heavy metals in the muscles of fishes collected from all the sites were within the permissible levels and are safe for the human consumption and public health.