Chapter 16 - Microbes-Assisted Remediation of Metal Polluted Soils

Abstract

The rapid increase in urbanization and industrial growth has led to the exploitation and pollution of valuable natural resources like soil and water. Soil pollution due to the toxic heavy metals, hazardous chemicals, and consequential contamination of groundwater, sediments, surface water, and food chain is one of the major environmental concerns of the modern era. Metal contamination of soil occurs due to the release of metals in the environment from several anthropogenic activities such as agriculture, disposal of urban and industrial wastes, mining, smelting, and various other industrial operations. Metals when present in higher concentration show phytotoxicity in plants and cause serious health issues in human beings due to their carcinogenic and mutagenic nature. Since metal pollution has serious implications for food safety, health, and environment, bioremediation of metal-contaminated soils using microorganisms can be explored as a promising approach toward a sustainable and eco-friendly mitigation of this problem. Microbes remediate heavy metals through different mechanisms such as redox reaction, bioprecipitation, extracellular complexation, and intracellular accumulation. Bioremediation, being a low cost, green, and environment-friendly option as compared to the conventional physicochemical remediation methods can play a pivotal role in the development of future remediation technologies. This chapter aims to highlight the current status, challenges, and opportunities in the bioremediation of heavy metals from contaminated soils.