Phytoremediation - A review

The pollution of environment i.e., soil, water and air is not uncommon. The contamination of first two with metals, heavy metals and radio nuclei has been on the increase since starting of industrial revolution. The primary sources of pollution include burning of fossil fuels, mining and smelting of metalliferous ores, municipal wastes, fertilizers, pesticides and sewage. The pollution of soil and water is posing threat to human, animal and plant life in various ways. Soil which is called a natural resource base for plant growth is becoming unfit for cultivation mainly due to contamination of heavy metals. These include Cd, Pb, Cr, Au, As, Cu, Zn, Se and Ni. Phytoremediation is the best option for cleaning up environment as it is the ecologically sustainable and environmentally viable technology. The Brassicaspecies are identified as good candidates for phytoextraction of heavy, metals especially Zn. EDTAand Citric acid are commonly used for induced phytoextraction ofPb. Rabbit foot grass was identified as suitable species for phytovolatilisation of Se from constructed wetlands. The aquatic plant species are regarded as best species for removing metals from contaminated water. Poplar trees are used for phytodegradation of harmful compounds like TNT. This green cure technology no doubt has the ability to clean up contaminated soil and water but slowly.