Phytoremediation of heavy metals from landfill soil using Polyscias fruticosa

Abstract

The presence of heavy metals in landfill soil by industrial or anthropogenic activities pose a risk to the environment and it is one of the major concerns. This study was to determine and evaluate the capability of Polyscias fruticosa in the phytoremediation of heavy metals from abandoned landfill soil. P. fruticosa was analysed to evaluate its tolerance and phytoremediation ability on landfill soil in a greenhouse study with a harvesting period of 1-month intervals. Ninety-six (96) cuttings from P. fruticosa were transplanted and had the same treatment in 500 g landfill soil. The roots, stems, and leaves of exposed and unexposed plants were dry-digested and heavy metals were determined using Atomic Absorption Spectrophotometer (AAS). The height and weight of dry biomass of exposed and unexposed plants were determined. The data obtained were subjected to a one-way analysis of variance and the least significant difference (L.S.D.) at probability level p<0.05. The highest accumulation in the roots occurred on Pb, followed by Cr, As, and Cd with concentrations 0.82, 0.68, 0.35, and 0.33 mg/kg, respectively. Heavy metals were not detected from unexposed plant and soil. The three indices, bioconcentration, translocation factors, and extraction coefficient, were found to be more significant (>1) on six months compared to other harvesting periods. The percentage removal was Cd 88%, As 87%, Cr 86%, and Pb 78%. The results indicate that P. fruticosa might be an effective species to reduce heavy metals from landfill soil.