Assessing radish (Raphanus sativus L.) potential for phytoremediation of lead-polluted soils resulting from air pollution

Abstract

The objective of this study was to investigate the capability of radish to extract lead from soils contaminated with lead resulting from air pollution. A randomized block experiment design was performed. The soil was contaminated with PbNO₃ and the treatments consisted of 180 (standard), 250, 350, 450, 800 and 1000 mg/kg lead. After development, plants were harvested and divided into shoots and roots. The lead content of each plant part as well as the soil-lead were measured. The results indicated a non-linear positive relation between the lead concentrations in soil and that accumulated in plant roots and shoots. By increasing the lead concentration in soil, its accumulation in plant tissues was also increased. Most of the extracted lead was accumulated in the roots (208.1 mg/kg) compared to shoots (27.25 mg/kg). Since radish can be seeded up to five times a year, and its yield may reach up to 20 t/ha, it can be used to remediate lead-polluted topsoils (0–10 cm).