Microbial transformation and degradation of polychlorinated biphenyls

• Published in: Environmental pollution (1987) Vol. 155; no. 1; pp. 1 - 12
• Main Authors: Field, Jim A., Sierra-Alvarez, Reyes
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.09.2008; Elsevier
• Subjects: Aerobiosis; anaerobic conditions; Anaerobiosis; Applied sciences; biodegradation; Biodegradation, Environmental; bioremediation; Biotransformation; Burkholderia cepacia; Chloroflexaceae group; Dechlorination; Dehalococcoides; Dehalogenation; Ecology; Ecology - methods; Environmental Pollutants; Exact sciences and technology; Global environmental pollution; literature reviews; methods; microbial activity; mineralization; Organohalogens; PCB; Pollution; Polychlorinated Biphenyls; redox reactions; Soil Microbiology; Organohalogens; Dechlorination; Dehalogenation; Biotransformation; PCB; Biodegradation; Microbial activity; Pollutant behavior; Polychlorobiphenyls; Review; Aerobe; Organic chlorine compounds; Persistent organic pollutant; Pollution; Position isomer; Anaerobe; Selfpurification; Chlorocarbon; Environment; Property structure relationship; Biotranstbrmation; Organic compounds
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2007.10.016

This paper reviews the potential of microorganisms to transform polychlorinated biphenyls (PCBs). In anaerobic environments, higher chlorinated biphenyls can undergo reductive dehalogenation. Meta- and para-chlorines in PCB congeners are more susceptible to dechlorination than ortho-chlorines. Anaerobes catalyzing PCB dechlorination have not been isolated in pure culture but there is strong evidence from enrichment cultures that some Dehalococcoides spp. and other microorganisms within the Chloroflexi phylum can grow by linking the oxidation of H 2 to the reductive dechlorination of PCBs. Lower chlorinated biphenyls can be co-metabolized aerobically. Some aerobes can also grow by utilizing PCB congeners containing only one or two chlorines as sole carbon/energy source. An example is the growth of Burkholderia cepacia by transformation of 4-chlorobiphenyl to chlorobenzoates. The latter compounds are susceptible to aerobic mineralization. Higher chlorinated biphenyls therefore are potentially fully biodegradable in a sequence of reductive dechlorination followed by aerobic mineralization of the lower chlorinated products. Higher chlorinated biphenyls are potentially fully biodegradable in a sequence of anaerobic reductive dechlorination followed by aerobic mineralization of the lower chlorinated products.