Investigating of the Phytoremediation of Lead and Cadmium by Indian Mustard Plant (Brassica juncea)

Lead and cadmium are among the most important heavy metals which have entered the life cycle of the earth as a result of human activities.  In this study, in order to evaluate the ability of Indian mustard to uptake heavy metals (cadmium and lead), a survey was performed as randomized complete block design in which each metal was added  to the plant in four concentrations zero (a control), 50, 100 and 200 mg/kg soil. The results showed that the highest concentration of lead in the root and shoot (aerial parts) of Indian mustard was 278.4 and 61.8 mg/kg, respectively, in the 200 mg/kg treatment, while the highest amount of cadmium in these two organs was 14.5, and 10.9 mg/kg respectively in the treatment of 100 mg/kg soil. Also, with the increase of lead concentration in the soil, the amount of this element in Indian mustard increased linearly with a high correlation coefficient, and the bio-concentration coefficient of lead in the plant roots was greater than one in all studied treatments. Finally, it was found that Indian mustard can be used as a bio-indicator of lead and stabilized it in its root, but it is not able to stabilize or extract significant amounts of cadmium from soil.