Reductive dechlorination of hexachlorobenzene to tri- and dichlorobenzenes in anaerobic sewage sludge.
Hexachlorobenzene was dechlorinated to tri- and dichlorobenzenes in anaerobic sewage sludge. The complete biotransformation of 190 microM hexachlorobenzene (approximately 50 ppm) occurred within 3 weeks. The calculated rate of hexachlorobenzene dechlorination was 13.6 mumol liter-1 day-1. Hexachlorobenzene was dechlorinated via two routes, both involving the sequential removal of chlorine from the aromatic ring. The major route was hexachlorobenzene----pentachlorobenzene----1,2,3,5-tetrachlorobenzene--- -1,3,5- trichlorobenzene. Greater than 90% of the added hexachlorobenzene was recovered as 1,3,5-trichlorobenzene, and there was no evidence for further dechlorination of 1,3,5-trichlorobenzene. The minor route was hexachlorobenzene----pentachlorobenzene----1,2,4,5-tetrachlorobenzene--- -1,2,4- trichlorobenzene----dichlorobenzenes. These results extend reductive dechlorination to poorly water soluble aromatic hydrocarbons which could potentially include other important environmental pollutants like polychlorinated biphenyls.
Fathepure
B Z
BZ
Department of Crop and Soil Sciences, Michigan State University, East Lansing 48824.
Tiedje
J M
JM
Boyd
S A
SA
D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D055598:Chemical Phenomena; D002621:Chemistry; D002722:Chlorobenzenes / Q000378:metabolism*; D006581:Hexachlorobenzene / Q000378:metabolism*; D010084:Oxidation-Reduction; D012722:Sewage
D002722:Chlorobenzenes; D012722:Sewage; C036720:trichlorobenzene; D006581:Hexachlorobenzene; C030387:1,2,3,5-tetrachlorobenzene