Cultivation of milk thistle in Pb-contaminated urban soils

In order to remediate heavy metal-contaminated soils of urban areas, we conducted an experiment using a pharmaceutical phytic species such as milk thistle (Silybum marianum (L.) Gearn.). The experiment was carried out using two different soil samples (one acid and one alkaline) from urban areas varying in their physicochemical attributes along with Pb levels. In every soil sample we applied three levels of contamination, 150, 300 and 450ppm Pb. Then, estimates of the available-DTPA extractable and pseudo-total concentrations of lead (Pb) were accomplished. Also, assessments of metal transport to different parts of milk thistle from the Pb-contaminated soils were conducted. The results of this experiment revealed that the highest concentration of Pb was found in underground part of the plant, also the Pb movement was higher in acid soil sample than in alkaline.