Status of Toxic Metal Pollution of Soil in and around Araromi Metal Scrap Dumpsite, Akure, Ondo State

Abstract

Most problems of soil pollution are associated with large amount of heavy metals deposited on it through disposed waste. This study was carried out to assess heavy metals (Fe, Zn, Pb, Cu and Cd) in soil samples around metal scrap dumps at Araromi vicinities of Akure South Local Government, Ondo State, Nigeria, in order to assess the effects of the dumps on the soils. A total of thirty nine soil samples were taken for laboratory analysis. The soil samples were collected using hand driven stainless steel auger at various depths at the dumpsite, and at various horizontal distances away from the dumpsite including human settlements close to the dumpsite. The heavy metals in the waste soils samples was sequentially extracted and quantified, using atomic absorption spectrometry (AAS). The findings revealed that Iron, Lead, Cadmium and Copper with concentration of 611.7 mg/kg, 200.8 mg/kg, 4.9 mg/kg and 103 mg/kg respectively, all exceeded National Environmental Standards and Regulation Enforcement Agency (NESREA) acceptable limit and index of 2007, except Zinc 229.2 mg/kg The order was Fe>Zn>Pb>Cu>Cd for the study area. A consistent trend showing a decrease in the concentration of toxic metals was observed at increasing depths and distances from dumpsite, which suggest a discontinuation or mitigation of anthropogenic input on the environment.