Phytoremediation of lead using Indian mustard (Brassica juncea) with EDTA and electrodics

The use of plants to remove toxic metals from soil (phytoremediation) is emerging as a cost-effective alternative to conventional methods. Because contaminants such as lead have limited bioavailability in the soil, methods to facilitate its transport to the shoots and roots of plants are required to the success of phytoremediation. Indian mustard (Brassica juncea) has been shown to be effective at accumulating high tissue concentrations of lead when grown in contaminated soil with the addition of a chelating agent, such as EDTA. The addition of an electric field around the plants is an alternative approach to increase the uptake of lead. In this work, bench scale studies illustrated the application of electrodic phytoremediation with EDTA for lead using Indian mustard. The effects of a range of parameters such as operating current/voltage with different concentrations, application time of EDTA and electric potential, and daily application time of electric potential were studied. The accumulation of lead in the shoots using 0.5 mmol/kg EDTA with electric potential increased by two- to four-fold compared to the use of EDTA only. The maximum lead accumulation in the shoots was obtained with the application of electric field I h per day for 9 days with EDTA. (C) 2003 Elsevier B.V All rights reserved.