Evaluation of Cd phytoremediation by Portulaca oleracea irrigated by contaminated water

Background: Worldwide, more than 10 million regions with an area of more than 20 million hectares are considered contaminated soils. The expansion in industrial activities and urbanization has led to accumulation of high concentration of cadmium (Cd) in soil and water resources, which is a serious danger for environment and human health. Phytoremediation is a technique recommended for the removal of heavy metals from contaminated soils, sediments, and waters. This study aimed to investigate the Portulaca oleracea in the removal of Cd from contaminated soil. Methods: To investigate the effect of P. oleracea phytoremediation on the removal of Cd, in 5 pots, 3 kg of soil was poured. And in each pot, 10 seeds were pursued. The pots were irrigated twice a week for 8 weeks with concentrations of 25, 50, 75, and 100 mg/L Cd. After 8 weeks, the amount of Cd of roots, shoots, and leaves was measured by atomic absorption spectrometry. Results: The results showed that Cd accumulation in purslane plants was significant (P = 0.008) and the highest Cd accumulation was in leaves and shoots, and increasing Cd concentration prevented plant growth and led to lower growth at higher concentrations. Conclusion: According to the results, P. oleracea can be used for the phytoremediation of Cd.