BIOREMEDIATION OF SITES POLLUTED BY COMME RCIAL PCBS - PROBLEMATICAL QUESTIONS AND PERSPECTIVES

Polychlorinated biphenyls (PCB) have been widely used in a number of i ndustrial applications for nearly 50 years. As a consequence of their intensive use, and due to the stability of the molecules, they have be come progressively widespread contaminants in soil, sediments and land fills. Because classical remediation technologies (confinement, incine ration, etc.) are generally expensive and not always efficient, altern ative methods involving biodegradation by microbial populations have b een developed. The two known pathways of biodegradation (oxidative and reductive), as well as factors affecting PCB degradation by microbial strains, are reviewed here. The different bioremediation strategies p roposed and those recently developed are examined and compared. The us e and study of new microorganisms, including cyanobacteria, are also e voked.