Assessment of Heavy Metals Presence in Selected Dumpsites within Igboora, Oyo State, Nigeria

Abstract

This study was carried out to evaluate the level of Cd, Pb, and Cr in some selected dumpsites within Igboora, Ibarapa Central Local Government of Oyo State. Soil samples were collected from Abattoir, Oja Igboora, Oja Oba, New Abattoir and Towobowo dumpsites. The control samples were collected at 20m away from each of the dumpsites. The samples were collected at two different sampling depths- 0-20cm and 20-40cm. The samples were replicated three times. All the data collected were analyzed using Genstat Statistical Package and means separated using Least Significant Difference (LSD). The results obtained revealed that the highest amount of Pb, Cd, Cr (232.99 mg kg-1, 28.53 mg kg-1 and 53.67 mg kg-1), respectively were recorded at Abattoir dumpsite. The quantity of lead in the selected dumpsites increased with the sampling depth. However, Cd and Cr values reduced with the sampling depth. All the values observed were significant at 5% level of probability. The value of Pb and Cd, recorded in all the dumpsites including the control sites were above the maximum limit recommended by WHO. Attention should therefore be paid to the presence of heavy metals in this area as crops grown in soils around these dumpsites could accumulate the metals and eventually get to food chain when such crops are consumed. Similarly, the fact that they were detected both at the upper layer and sub-soil means they could contaminate the ground water around this area.