Heavy metal cleanup from contaminated soil by phytoremediation: An update

Phytoremediation can be defined as a modern method of removing pollutants from water bodies and soil using plants as a means of remediating the environment for a relatively cheaper price while ensuring environmental safety compared to traditional techniques, particularly for soil and water containing heavy metal pollutants. The approach employs various processes such as phytoextraction where pollutants are sequestered in harvestable plant biomass, phytostabilization where movement of pollutants is inhibited, phytovolatilization which refers to the conversion of pollutants to a volatile form, and phytodegradation where plant tissues that contain the pollutants need to be broken down significantly transforming the tissues. Of these methods, phytoextraction has more commercial applicability, especially in regions with diffused pollution. The efficiency of phytoremediation varies according to the bioavailability of heavy metals, soil characteristics, and availability of selective vegetative cover. Various aspects of phytoremediation of the heavy metals have been discussed in this article with more focus on the methods of phytoremediation. It is essential to select appropriate plants for different methodologies, such as use of high-biomass plants to limit food chain contamination and use of aromatics for non-edible plant by-products. Besides, this review highlights the significance of phytoremediation as a well-suited solution for cleanup of heavy metal contaminated soil and its contribution to a clean and healthier surrounding.