Phytoremediation of toxic metals and their post-remediation management approaches

Toxic metal contamination is a serious concern nowadays due to their persistence, toxicity, and bioaccumulation properties. These metals cause severe effects on human health and the environment, and even at low concentrations, they may contribute to severe diseases, including cancer. Phytoremediation is one of the eco-friendly and cost-effective methods for the remediation of toxic metals. Hyperaccumulator plants absorb and tolerate higher concentrations of toxic metals through various mechanisms, including chelation, antioxidant defense, compartmentalization, uptake, and storage in their tissues. The mitigation of toxic metal contamination through phytoremediation is a cost-effective approach. However, it must include thorough assessments of its impacts on herbivores and humans during and after the remediation process. Herbivores eating these hyperaccumulators may develop toxic metal accumulation, which could lead to neurological, developmental, and other disorders. Post-phytoremediation strategies for managing biomass include incineration, pyrolysis, gasification, and composting. Biomass management, such as thermal treatments like pyrolysis or biological methods like composting are used to prevent contaminants from re-entering the soil. However, the risk of secondary pollution persists if handling protocols are not strictly regulated. Though phytoremediation presents an encouraging solution to the problem of toxic metal pollution, successful phytoremediation projects require the management of post-remediation biomass. This review article focuses on the concept of phytoremediation of toxic metal contamination, including the mechanism of metal binding and sequestration in hyperaccumulator plants. It also focuses on sustainable strategies for environmental protection and economic feasibility to promote informed decision-making in phytotechnologies.