Immobilization of Heavy Metals in Contaminated Soils Using Phosphate-Solubilizing Fungi: Mechanisms and Advantages

Abstract

With rapid industrialization, excessive use of agrochemicals, and improper waste disposal systems, the contamination of soil and water by toxic heavy metals such as cadmium, lead, arsenic etc., is increasing spontaneously and has become a global menace in recent times.It is attracting global attention due to their deleterious impact on humans and ecosystems.Little achievements have been made with regards to effectively containing or reversing the dangerous levels of heavy metal pollution of the environment.Therefore, there is an urgent need for effective and sustainable remediation methods.Several remediation strategies have been proposed to tackle the problem of continuous heavy metal contamination of soil.However, most of the strategies have some limitations of ecological concerns ranging from the high cost of operations, generation of sludge and wastes, inefficiency, and unsustainability.This review discusses the various advantages and mechanisms involved in the in-situ immobilization of heavy metals in contaminated soils by exploiting the interactions between phosphate-solubilizing fungi and phosphate minerals and fertilizers.Phosphate-solubilizing fungi (PSF) are beneficial microbes capable of solubilizing inorganic phosphorus compounds or phosphate-containing organic compounds to release phosphorus (P).The activities of PSFs in the soil ensure the availability of much-needed P to plants and microorganisms in the soil.