A Review of Phytoremediation of Heavy Metals Using Macrophytes: Mechanisms, Efficacy, and Future Prospects

Heavy metal (HM) contamination in aquatic habitats has increased significantly due to the fast pace of industrialization, posing serious risks to environmental stability and public health. Among the available technologies, phytoremediation a plant-based or “green” technology has emerged as a promising approach, especially when utilizing aquatic macrophytes. Certain aquatic macrophyte species can cope with these harsh circumstances, even if there is a high amount of heavy metal contaminants in the water. The potential of this method has been further enhanced by the discovery of hyperaccumulator plants, with the capacity to absorb, move, store, and concentrate significant amounts of contaminants in their harvestable parts. Phytoremediation involves different mechanisms, including phytoextraction, phytovolatilization and rhizofiltration. Numerous aquatic plant species like Eichhornia, Lemna, Potamogeton, Spirodela, Wolffia, Azolla, and Pistia have shown effectiveness in the removal of contaminants like arsenic, cadmium, zinc, copper, lead, chromium, and mercury from polluted water bodies. This review emphasizes on aquatic macrophytes' unique remediation properties and their function as a crucial component of phytotechnologies to reduce aquatic pollution.