Abstract: E-waste disassembly activity is a potential threat to soil quality and safe production of crops in cropland nearby. We investigated the accumulation of Cr, Ni, Zn, Mn, and Pb in root-surrounding soils, roots, stems, and leaves of ten dominant plant species growing in cropland near an E-waste dismantling site. We used single factor pollution index, Nemerow comprehensive pollution index, and potential ecological harm index to evaluate the ecological risk of heavy metals. The absorption and transport of heavy metals in the soil-plant system were explored by bio-concentration factor, bio-transfer factor, and correlation analyses. The results showed that the pollution level of five heavy metals in soils followed the order Zn>Cr>Ni>Pb>Mn, but their ecological risk was very low. All the 10 plant species had low capacity to accumulate heavy metals. Zn was easily transported to the shoots. Root was the most sensitive organ to the content of heavy metals in soil, followed by leaf, and stem was less sensitive. The adsorption and transport of different heavy metals were synergetic in soil-plant system. These findings provide a theoretical basis for the mechanisms of adsorption and transport of different heavy metals, ecological risk evaluation, and heavy metal pollution remediation in the E-waste dismantling site.

Key words: plant, synergistic effect, adsorption and transport, correlation analysis, pollution level.