Review of Heavy Metal Removal from Soil: Methods and Technologies

Abstract

Soil health is vital for ecosystem functioning, agriculture, and human well-being, yet heavy metal contamination poses significant risks to environmental and public health. This review examines various methods for removing heavy metals from contaminated soils, focusing on physical, chemical, and biological remediation techniques. Sources of contamination, including industrial activities, mining, and improper waste disposal, are discussed, alongside the environmental and health impacts of heavy metals like lead, cadmium, and mercury. Physical techniques such as soil washing and excavation effectively reduce contamination but generate secondary waste and incur high costs. Chemical methods, including soil stabilization and chemical leaching, immobilize or extract metals but may risk recontamination. Biological approaches like phytoremediation and bioremediation leverage natural processes for eco-friendly remediation, though they often require longer timescales for significant results. Emerging technologies, such as nanotechnology and biochar application, show promise for enhancing remediation efficacy. However, challenges remain, including economic constraints, regulatory inconsistencies, and the need for sustainable, long-term solutions. Future directions include integrating various remediation techniques, developing eco-friendly technologies, and emphasizing long-term monitoring to ensure the effectiveness of remediation efforts. This comprehensive overview aims to inform future research and policy development to address heavy metal contamination sustainably.