Chloroethenes contaminants in the environment: Still a cause for concern

Prior to 1980, chloroethenes were generally believed to be recalcitrant to degradation. Efforts to remediate sites polluted by this group of compounds were thus limited to the ineffective and tedious pump-and-treat method. The environmental significance of chloroethenes and the absence of effective alternative physical remediation methods have warranted intense scientific investigation into the role of microorganisms for detoxifying these environmentally important compounds to benign products. Several microbial mechanisms have therefore been identified to significantly degrade these compounds in soil and ground water polluted systems. This paper provides a mini-review of such mechanisms with the view of understanding the biodegradation processes for better exploitation for bioremediation of chloroethene contaminants, which continue to be of serious environmental challenges. Key Words: Bioremediation; Chloroethenes; Cometabolism; Oxidation, Reductive dechlorination. African Journal of Biotechnology Vol.3(12) 2004: 675-68