Heavy metals contamination and their phytoremediation in soil and water for sustainable environmental restoration
Kunal Yadav, Deo Kumar, Arbind Kumar Gupta, Bhoomika Gupta, Praduman Tyagi, Arjun Sharma, Prasenjit Kumar Patra, Prasanta Kumar Patra, A. Krishna Chaitanya
Abstract
Heavy metals, such as cadmium (Cd), mercury (Hg), and lead (Pb), are persistent environmental contaminants that pose significant risks to soil, water, and human health. These metals accumulate in ecosystems, leading to reduced soil fertility, deteriorating water quality, and ultimately entering the food chain. Exposure to heavy metals has been linked to various diseases, including itai-itai disease (Cd), Minamata disease (Hg), and blue baby syndrome (nitrate contamination in water). While traditional remediation methods are effective, they tend to be costly, complex, and have negative environmental impacts, limiting their broad applicability. Phytoremediation is emerging as a promising, cost-efficient, and eco-friendly approach to address heavy metal contamination. This green technology utilizes plants' natural capabilities to interact with contaminants through processes such as phytoextraction, phyto-stabilization, phytodegradation, and rhizofiltration. Plants capable of absorbing or degrading metals like Cd, Hg, nickel (Ni), and Pb are grown to either extract contaminants from soil or water or stabilize them to prevent further spread. For example, in phytoextraction, plants absorb heavy metals through their roots and store them in their biomass, while phyto-stabilization helps immobilize metals in the soil. Phytodegradation uses plant metabolic processes to detoxify compounds, and rhizofiltration targets contaminants in water via plant roots.As a sustainable solution, phytoremediation offers an environmentally friendly method to mitigate heavy metal pollution without harming ecosystems, making it a viable option for restoring contaminated sites. This review explores the mechanisms of phytoremediation and its potential in alleviating the toxic effects of heavy metals on soil and water health.