Abstract

Removal of Toxic Heavy Metals from Biosphere by Plants

Author(s): Smriti Khare, Richa Khare and Jaya

Bioremediation can be defined as any process that uses biological organisms and their enzymes to return the environment altered by contaminants to its original condition. Remediation is the removal of pollution or contaminants from land for the general protection of the environment so that land can be reused. Phytoremediation is the use of living green plants for in situ risk reduction and/or removal of contaminants from contaminated soil, water, sediments, and air. Specially selected or engineered plants are used in the process. Risk reduction can be through a process of removal, degradation of or containment of a contaminant or a combination of any of these factors. It is an energy efficient, aesthically pleasing method of remediating sites with low to moderate levels of contamination. There are more than 400 plant species have been identified to have potential for soil and water remediation. It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come. This cost-effective plant-based approach to remediation takes advantage of the remarkable ability of plants to concentrate elements and compounds from the environment and to metabolize various molecules in their tissues. Toxic heavy metals and organic pollutants are the major targets for phytoremediation. The future of phytoremediation is still in research and development phase. Both agronomic management practices and plant genetic abilities need to be optimised to develop commercially useful practices.