Abstract

Phytoextraction is a non-destructive, cost-effective and safe alternative to conventional cleanup techniques of contaminated soils. In this study, the ability of two plants species Synedrella nodiflora and Sida fallaxgrowing naturally around the abandoned Asafo Railway Station in Kumasi for selective extraction and accumulation of four heavy metals (Pb, Cu, Fe and Zn) were studied using Atomic Absorption Spectroscope. The degree of translocation of these metals by the plants was also calculated. High translocation indices greater than one in the case of Fe and Zn were recorded in S. nodiflora and S. fallax,respectively. However Cu and Pb examined in this study were not effectively extracted nor transported within the plants, hence these plants are excluders of Cu and Pb. The soil plant transfer coefficient for both plant species were calculated for each metal. The highest translocation coefficient value in this study for both plants was recorded for Zn. The translocation coefficient values for Pb and Cu were not significant in both plants, hence these plants can be described as Pb and Cu extruders but potential candidates for Fe bioaccumulation using phytoextraction.

Key words: Contaminated soil, heavy metals, phytoextraction, transfer coefficient, translocation index.