Biological strategies for heavy metal removal

Abstract

Recently, there has been a growing interest in technology called phytoremediation which includes the employment of living plant organisms for cleaning the environment. Phytoremediation technologies rely on the cultivation of species of plants that are able to grow in a contaminated environment. The manner in which the plant interacts with heavy metals depends mainly on the type of contamination, species of plant as well as conditions. Few plant species have the capability to accumulate metals in their own cells, others are able to incorporate them into their metabolic pathways. Moreover, thanks to special chemical compounds secreted by roots, these plants can cause binding of harmful substances which leads to limiting their flow into soil. These processes are the result of the natural adaptation of plants to the prevailing conditions, and these plants are treated as bioindicators of selected elements. The chapter presents biological strategies for the elimination of heavy metals from polluted habitats including processes of phytoextraction, phytostabilization, phytodegradation, phytostimulation, phytovolatilization and phytofiltration.