Heavy metal pollution: an alarming environmental threat andemergingremediation approaches

Abstract

Heavy metal contamination is a critical threat to environmental and human health due to the toxicity, persistence,andbioaccumulative nature of metals such as lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg). Conventional remediationtechniquesincluding chemical Precipitation, reverse osmosis, nanofiltration, electrokinetic remediation is often limited by high costs andrisksofsecondary pollution. Recent advances, however, have introduced sustainable and interdisciplinary strategies, integratingbiological,chemical, and nanotechnological approaches. Phytoremediation, through processes such as phytodegradation, phytovolatilization,phytoaccumulation, and phytoextraction, employs plants and associated soil microbes to mitigate pollutants. Bioremediationwithmetaltolerant plants and microorganisms, nano-bioremediation utilizing engineered nanoparticles, and hybrid electrochemical methodshaveshown enhanced effectiveness in both aquatic and terrestrial systems. This review summarizes the current state of heavymetalremediation technologies, emphasizes recent innovations, and highlights the importance of integrated, eco-friendlyapproachesforscalable applications. Future research should focus on combined treatment strategies and real-time monitoring systems toeffectivelyaddress complex, mixed-contaminant environments.