MICROBIAL REMEDIATION OF HEAVY METALS CONTAMINATION IN SOIL

Abstract

Heavy metals are metals with density above 5g/cm3 which occur
naturally in the environment. However, the indiscriminate discharge arising from
geochemical and anthropogenic activities have remained a galloping source of contamination
in the ecosystem. They can be mitigated through the use of microorganisms such as
Pseudomonas, Bacillus and Aspergillus species. The mechanisms utilized by microbes in
heavy metals remediation include change in biochemical pathways that obstruct metal uptake,
enzymatic transformation of metals to harmless forms and the use of exact effluent system for
reducing intracellular concentration of metals. Factors such as physicochemical and
biological are known to influence heavy metal remediation in contaminated sites. Prolonged
exposure of such heavy metals could have deleterious health effects on human life including
inhibition of libido in male reproductive systems and obstruction of ovulation in females as
well as in other terrestrial and aquatic biota. The use of microorganisms in cleaning up heavy
metals contaminated sites is a viable and sustainable one as it overcomes the drawbacks
encountered in other methods of heavy metal treatments. This leads to a healthy environment
and guarantees public health of it teeming citizens.