Bioremediation Options for Heavy Metal Pollution

Abstract

Background.Rapid industrialization and anthropogenic activities such as the unmanaged use of agro-chemicals, fossil fuel burning and dumping of sewage sludge have caused soils and waterways to be severely contaminated with heavy metals. Heavy metals are non-biodegradable and persist in the environment. Hence, remediation is required to avoid heavy metal leaching or mobilization into environmental segments and to facilitate their extraction.Objectives.The present work briefly outlines the environmental occurrence of heavy metals and strategies for using microorganisms for bioremediation processes as reported in the scientific literature.Methods.Databases were searched from different libraries, including Google Scholar, Medline and Scopus. Observations across studies were then compared with the standards for discharge of environmental pollutants.Discussion.Bioremediation employs microorganisms for removing heavy metals. Microorganisms have adopted different mechanisms for bioremediation. These mechanisms are unique in their specific requirements, advantages, and disadvantages, the success of which depends chiefly upon the kind of organisms and the contaminants involved in the process.Conclusions.Heavy metal pollution creates environmental stress for human beings, plants, animals and other organisms. A complete understanding of the process and various alternatives for remediation at different steps is needed to ensure effective and economic processes.Competing interests.The authors declare no competing financial interests.

Recent Advances in Biosorption of Copper and Cobalt by Filamentous Fungi

“…Numerous reports have demonstrated that in heavy metal polluted environments, microbial populations develop the ability to adapt to the high contamination levels ( Forster, 2003 ; Narendrula-Kotha and Nkongolo, 2017 ; Coelho et al, 2020 ). Nevertheless, there are concerns over heavy metal pollution from industries including mining, electroplating, dyeing, and tannery ( Shukla and Vankar, 2014 ; Kapahi and Sachdeva, 2019 ). To address the effect of heavy metal contamination, chemical methods such as ion-exchange, electrochemical treatment, and chemical precipitation have been developed to control excess heavy metals in wastewater and agricultural fields ( Shukla and Vankar, 2014 ).…”

“…These conventional methods are usually expensive and ineffective whenever heavy metal concentrations in the environment occur in very low concentrations. Therefore, the option to complement and integrate conventional methods with biological methods such as filamentous biosorption and bioaccumulation is becoming increasingly attractive ( Kapahi and Sachdeva, 2019 ). The basic and simplified laboratory process for fungal biosorption is demonstrated in Figure 1 .…”

Environmental Impacts of Heavy Metals and Their Bioremediation

“…& Arthrobacter sp., P.aeruginosa & B.subtilis, S.cerevisiae & P.aeruginosa, S.cerevisiae and B.subtilis). Biosorption by bacteria ((Bacillus), cocci (Streptococcus), filamentous (Actinomyces) and spiral (Vibrio cholera)) is an inexpensive and efficient technique to remove pollutants, like heavy metals, from wastewater [48,49]. Different species of algae are present in large amounts in marine ecosystems [50].…”

Molecular tools and applications of Euglena gracilis: From biorefineries to bioremediation

“…However, current bioremediation technologies, either chemical or physical, are complex, energy-demanding and costly (Khalid et al, 2017). One of the current options studied is to find a biological solution to the problem (Kapahi & Sachdeva, 2019).…”

“…Studies into bioremediation of heavy metals by microorganisms have mainly focused on the bioaccumulation of heavy metals in the cell biomass whereas post‐management of the accumulated metals is not often addressed (Kapahi & Sachdeva, 2019). While different techniques such as incineration, landfilling and recycling have been explored to find ways to manage heavy metals, an economical and environmentally sustainable disposal method is yet to be found.…”