Phytoremediation of Heavy Metals: Techniques, Challenges, and Prospects

Heavy metals, characterized by their high atomic mass and density, can pose significant risks to soil, water, plants, and human health. Contamination sources include manufacturing activities, mining, farming practices, and improper waste management. Metals such as arsenic, mercury, lead, chromium, and cadmium are most toxic with health consequences that can result from organ dysfunction to cancer. Conventional remediation techniques usually face challenges in due to high costs and secondary pollution. Phytoremediation, an eco-friendly alternative, uses plants to absorb, stabilize, or degrade toxic metals in contaminated environments. Among the techniques found to effectively mitigate soil and water pollution are phytoextraction, phytostabilization, phytovolatilization, and rhizofiltration. On the other hand, progress in genetic engineering and the integration of plant growth-promoting rhizobacteria (PGPR) has led to a greater efficiency of phytoremediation. Nevertheless, problems such as prolonged remediation duration and poor remediation performance in heavily contaminated environments still present. This review discusses the technique, applications and developments of phytoremediation, providing insight into its utility for environmentally sustainable management.