Analysis of concentration and accumulation of heavy metal cadmium in four selected terrestrial plants

Contamination of soils with toxic metals has often resulted from human activities, especially those related to mining, industrial emissions, disposal or leakage of industrial wastes, application of sewage sludge to agricultural soils, manure, fertilizer and pesticide use. Phytoremediation is the term applied to a group of technologies that use of plants to reduce, remove, degrade, or immobilize environmental toxins, primarily those of anthropogenic origin with the aim of restoring area sites to conditions usable for private or public applications. Some plants naturally survive in heavy metal contaminated soils because of their ability and accumulate them into their tissues. The ability of these plants to remove contaminants from the soil has been the subject of various recent studies. These plants are normally slow growing and producing small biomass but, they accumulate heavy metals in their tissues lowering the quantity and controlling the movement of heavy metals through the soil profile. From the present study it was found that the heavy metal cadmium accumulation was more in leaves when compared to stem and roots of four experimental plants. The findings show that Datura innoxia plant has up taken 80 – 85 % of cadmium from contaminated soil which will have direct application to remediate toxic metals from contaminated soil – water environment. It was noted that Datura innoxia is the suitable candidate plant for phytoremediation operation.