Phytoremediation of toxic metals from soil and waste water.

Phytoremediation is an emerging technology, which uses plants and their associated rhizospheric microorganisms to remove pollutants from contaminated sites. This plant based technology has gained acceptance in the past ten years as a cheap, efficient and environment friendly technology especially for removing toxic metals. Plant based technologies for metal decontamination are extraction, volatilization, stabilization and rhizofiltration. Various soil and plant factors such as soil's physical and chemical properties, plant and microbial exudates, metal bioavailability plant's ability to uptake, accumulate, translocate, sequester and detoxify metal amounts for phytoremediation efficiency. Use of transgenics to enhance phytoremediation potential seems promising. Despite several advantages, phytoremediation has not yet become a commercially available technology Progress in the field is hindered by lack of understanding of complex interactions in the rhizosphere and plant based mechanisms which allow metal translocation and accumulation in plants. The review concludes with suggestions for future phytoremediation research.