Level of Heavy Metals in Selected Vegetables Collected from Ijagun Dumpsite in Ogun State, Nigeria

Abstract

Wastes from dumpsites constitute a major challenge for plants, human and environmental health. This study investigated the levels of heavy metals in stems and leaves of three (3) Vegetables and soil samples obtained from Ijagun dumpsite, located in Ijebu Ode, Ogun state. The samples were digested with mixed acids and aliquots of the extracts were analyzed for Zinc (Zn), lead (Pb), Cobalt (Co) and Copper (Cu) using the Atomic Absorption Spectrometry (Perkin Elmer A Analyst 700 model). The results obtained showed that there was an increase in the level of selected heavy metals observed in the topsoil compared with the underground soil collected from the dumpsite. The level of the metals present in the topsoil was in the order Zn > Pb >Cu > Co. The stem of Celosia argentea and Cochorus olitorius accumulate more heavy metals compared with the leaf. The level of these selected heavy metals were observed to be far above the WHO/FAO and NAFDAC permissible values in plant except Co in the stem and leaf of Celosia argentea and Talinum triangulae, indicating that the leaf and stem of vegetables from Ijagun dumpsite pose serious health threat to human. However, C. olitorius and C. argentea with high absorption ability for Zn, Pb and Cu could serve as a phytoremediator for soils contaminated with these metals.