COMPARATIVE ASSESSMENT OF HEAVY METALS UPTAKE OF VEGETABLES CULTIVATED ON A DUMPSITE AT ABRAHAM ADESANYA POLYTECHNIC IJEBU-IGBO, OGUN STATE, NIGERIA.

Abstract

Growing and harvesting of plants on contaminated site as remediation method is a technique that may be employed for the purpose of environmental remediation. Seeds of jute (Corchorus Olitorius), spinach (Celosia argentea) and okra (Abelmoschus esculentus) were planted on a dumpsite at Abraham Adesanya Polytechnic Ijebu Igbo, Ogun state. They were harvested five weeks after visible growth and maturation was observed. The soil from the dumpsite and harvested vegetables were dried, digested and analysed for possible absorption of heavy metals (Lead, Manganese, Copper, Cadmium and Iron) using Atomic Absorption Spectrophotometer. The analyses revealed an appreciable level of concentration (mg/kg) of manganese, iron, lead, copper and cadmium in the cultivated vegetables. However, a higher absorption capacity for Fe was observed in Abelmoschus esculentus which revealed its potential as soil remediation for Fe. Movement of Cd was also strong from the soil to all the cultivated vegetables but mild for Cu, Pb and Mn. The results obtained for the cultivated vegetables showed they are presently within the safe limits of NAFDAC and European Union but may later pose a health risk to consumers if the constant practice of refuse and sewage disposal of inorganic contaminants on the dumpsite is not controlled.