Evaluation of metallic element translocation in some plants grown on abandoned waste dump sites around Owerri, Imo State, Nigeria

The study evaluated metallic element translocation in some plants grown on abandoned waste dump sites around Owerri, Imo State, Nigeria. Metallic element (Cr, Fe and Pb) level in soil and different parts of Carica papaya (CP), Vernonia amygdalina (VA), and Musa acuminata (MA) grown within the study sites were determined. Bio-concentration factor (BCF) and ratio of translocation (TF) of Cr, Fe, and Pb were evaluated. Fe level was the highest in soil (284.67 ±0.51mg/kg) followed by Pb (51.04 ±0.83 mg/kg), also in plant parts Fe showed 30.77 ±0.40 mg/kg while Cr has 9.06 ±0.20 mg/kg. Metallic element levels in the abandoned waste dump sites were greater than values obtained from the control. Single metal pollution index (Pi) suggested that metallic contaminant levels in the area has reached warning limit. Ecological risk analysis revealed low values. The results indicate that monomial ecological danger or risk (Et) and potential ecological risk index (Ri) posed by the metallic elements have little or no consequence. BCF value for Cr, Fe and Pb well less than one (< 1) in all the plants. TF analysis indicated that 59.26 % of the metallic elements have their TF less than (< 1), while 40.74% were slightly above one (> 1). Results of the study imply that the analyzed samples posed low risk. However, the study recommends discontinuation of cultivation of edible crops in the area. This is due to the tendency of metallic elements to bio-concentrate and bio-accumulate in living organisms after a long period.