Heavy Metal Contents in Celosia argentea,Lycopersicon esculentum and Aloe Vera Planted on Contaminated Abule Egba Dump Soil

Abstract

Most residents use dump soil as manure to plant vegetables and Aloe Vera in their garden without knowledge of the level of heavy metal contaminated in the soil. It was this concern that prompted the determination of heavy metals in the edible part of Celosia argentea, Lycopersicum esculentum and Aloe Vera younger clone plants planted on the dump soil and the control on Yaba College of Technology Botanical garden. The plants were allowed to grow for eight weeks before harvested. The harvested samples were digested with acid and heavy metal concentrations were determined using Atomic Adsorption Spectrophotometry. The concentration of heavy metal in Celosia argentea from dump soil and the control in mg/g are Cu (13.21, 0.62), Zn (29.30, 0.76), Fe (48.51, 7.82), Cd (2.27, ND), Pb (3.64, ND) Ni (1.48, ND) respectively. The concentration in the edible part of Lycopersicum esculentum are: Cu (36.53, 2.16), Zn (46.84, 12.70), Fe (64.34, 18.23), Cd (3.70, ND), Pb (5.35, ND), Ni (2.57, ND) respectively. The concentration in the Aloe Vera tissue are: Cu (19.82, 1.86), Zn (28.19, 1.15), Fe (32.74, 2.43), Cd (1.22, ND), Pb (2.62, ND), Ni (1.17, ND) respectively. The heavy metal concentrations uptake in the plants is higher than the permissible levels set by FAO/WHO. These results show that the level of heavy metal contamination in dump soil is very high and not suitable as manure because of health hazard associated with the level of heavy metal contamination.