Phytoremediation: A multidisciplinary approach to clean up heavy metal contaminated soil

Abstract

Environmental pollution due to heavy metals is a growing concern worldwide. Human activities such as industrial discharge, mining, smelting, hazardous solid waste disposal, etc. mainly contribute heavy metals to the soil. Persisting heavy metals in the soil can be taken up by plant tissues and can enter the biosphere and aggregate up in the trophic levels of the food web. Several physical, chemical and biological remediation techniques ( in-situ as well as ex-situ ) are available for the cleanup of heavy metal contaminated soil. Phytoremediation is the most sustainable (economical and eco-friendly) technique among these. Though, phytoremediation is less efficient than physical methods, it is still in the developmental stage and therefore, redirection of research activities for its commercial use is needed. This review summarizes the roles of soil chemistry, plant physiology and microbiology (plant-microbiology interaction) in assisting the phytoremediation of heavy metal contaminated soil. The limitations and future directions towards sustainable phytoremediation are also discussed in this review. • Phytoremediation technology to clean up heavy metal contaminated soil is reviewed. • Factors affecting the phytoremediation have been discussed. • Phytoremediation has become much popular in the recent past. • China, India, and US are the leading countries in research on phytoremediation. • Limitations of the phytoremediation technique are discussed.