Bioremediation of metals: Microbial processes and techniques

Abstract

Bioremediation is a technology that uses metabolic processes to degrade or transform contaminants, so that they remain no longer in harmful form. In some cases, the contaminant is the primary part of the metabolic process, acting as a main source of carbon and energy for the microbial cell. In others, it is transformed into a second substance, serves as a primary energy or carbon source. This co-metabolism process may be purely fortuitous, and the microorganism gains nothing from the process. In case of metals, it is only the biotransformation process that was exploited widely as a bioremediation strategy. After the use of super bug in cleaning up oil spills, there has been numerous successful stories of bioremediation technique in clean-up of vast areas of contaminated environments (USGS 1997). This chapter focuses on the role of metal-microbial relationships, microbial processes governing bioremediation and various techniques available for metalcontaminated sites. This chapter also throws light on bioremediation techniques used exclusively for chromium-contaminated soils and possible future developments in the field of bioremediation. © 2007 Springer-Verlag Berlin Heidelberg.