Uptake and Removal Capability of Toxic Heavy Metals From the Industrial Discharge of Mobarakeh Steel Complex by Metal Accumulating Plants

Heavy metals are largely found in dispersed form in rock formations. Industrialization and urbanization have increased the anthropogenic contribution of heavy metals in the biosphere. Heavy metal pollution not only affects the production and the quality of crops, but also influences the quality of the atmosphere and water bodies, and threatens the health and life of human beings. Clean-up technologies have been developed for the removal of heavy metals but often these are expensive or have some environmentally deleterious consequences. Phytoremediation emerged in the early 1980s is an important technology for remediation of contaminated sites. One of the most promising phytoremediation technologies is phytoextraction using hyperaccumulators to remove heavy metals from contaminated soils. However, the known hyperaccumulator plants usually accumulate only a specific element and are usually small. Recently, most attention is focused to the plants that produce high biomass and are tolerant to the soils pollutted with heavy metals. T. caerulescens was found to colonize areas with high Cd, Cu, Pb, and Zn present in soils due to mining. M. chenopodiifolia has good potential for absorbing Pb and Zn. Eruca sativa is tolerante to soil pollution with heavy metals and can accumulate Pb and Cd from contaminated soils. B. napus accumulated cadmium and zinc and translocated these elements into the harvestable parts of the plant. S. nigrum is often found in contaminated areas. It has previously been identified as a Cd hyperaccumulator. H. annuus is known for its high biomass yield. In addition, it is tolerant to soil pollution with heavy metals. Z. mays produce high biomass as well. In this study, we studied the capability of stability, growth, and uptake of heavy metals by means of T. caerulescen, Z. mays, H. annuus, E. sativa, B. napus, S. nigrum, and M. chenopodiifolia on the industrial discharge of Mobarakeh Steel Complex.