Investigating the effect of Dimercaprol on phytoremediation of lead by Zea mays, Helianthus annuus, Sinapis arvensis

Application of plants to remove heavy metals from soil (phytoremediation) is expanding due to its cost- effectiveness as compared to conventional methods and it has shown a great potential. Since contaminants such as Pb have a limited bioavailability in the soil, methods to facilitate their translocation to the shoots and roots of plants are required for efficient phytoremediation. The present pots experiment were to investigate the effect of Dimercaprol chelator with different concentration (0, 1.5, 3 mmol Dimercaprol chelator kg-1) and also different ranges of Pb (100, 200 mg Pb kg-1) and a control group, on the amount of Pb accumulation, by corn (Zea mays), sunflower (Helianthus annuus) and mustard (Sinapis arvensis). The results showed that the amount of Pb accumulation increased as the Pb concentration was increased. Also the results of this experiment showed that the addition of Dimercaprol chelator is most likely to increase the bioavailability of Pb and consequently the accumulation of this heavy metal in the shoots. The highest accumulation of Pb was noticed with the highest does of Dimercaprol chelator (3 mmol Dimercaprol chelator kg-1) and Pb (200 mg Pb kg-1) in the shoots of Helianthus annuus.