Polychlorinated biphenyls reductive

Promotes pollution prevention, the use of safer chemicals through regulatory and vohmtaiy efforts, risk reduction so as to minimize exposure to existing substances such as lead, asbestos, dioxin, and polychlorinated biphenyls, promotes the public understanding of risks by providing understandable, accessible and complete information on chemical risks. 

Wu Q, DL Bedard, J Wiegel (1997a) Effect of incubation temperature on the route of microbial reductive dechlorination of 2,3,4,6-tetrachlorobiphenyl in polychlorinated biphenyl (PCB)-contaminated and PCB-free freshwater sediments. Appl Environ Microbiol 63 2836-2843. 

Bedard DL, JE Quensen III (1995) Microbial reductive dechlorination of polychlorinated biphenyls. In Microbial transformation and Degradation of Toxic Organic Chemicals (Eds LY Yonng, CE Cemiglia), pp. 127-216. Wiley-Liss, New York. 

Fagervold SK, JEM Watts, HD May, KR Sowers (2005) Sequential reductive dechlorination of meta-chlorinated polychlorinated biphenyl congeners in sediment microcosms by two different types of Chloroflexi phylotypes. Appl Environ Microbiol 71 8085-8090. 

Wu Q, JEM Watts, KR Sowers, HD May (2002) Identification of a bacterium that specifically catalyzes the reductive dechlorination of polychlorinated biphenyls with doubly flanked chlorines. Appl Environ Microbiol 68 807-812. 

Drenzer NJ, T1 Eglinton, CO Wirsen, HD May, Q Wu, KR Sowers, CM Reddy (2001) The absence and application of stable carbon isotope fractionation during the reductive dechlorination of polychlorinated biphenyls. Environ Sci Technol 35 3310-3313. 

Quensen, J.F., III, M.A. Mousa, S.A. Boyd, B.J.T. Sanderson, K.L. Froese, and J.P. Giesy. 1998. Reduction of aryl hydrocarbon receptor-mediated activity of polychlorinated biphenyl mixtures due to anaerobic microbial dechlorination. Environ. Toxicol. Chem. 17 806-813. 

Sokol, R.C., C.M. Bethoney, and G.Y. Rhee. 1998. Reductive dechlorination of preexisting sediment polychlorinated biphenyls with long-term laboratory incubation. Environ. Toxicol. Chem. 17 982-987. 

The water insoluble, highly chemically and thermally stable PCBs used as insulating fluids for transformers and capacitors, in paints, copy paper, etc., are extremely toxic, persistent in the environment and bioaccumulating. PCBs are currently destroyed by incineration of concentrates at high temperatures or chemically with sodium metals or organosodium. Both processes are costly. The cathodic reduction/elimination of the chlorine from polychlorinated biphenyl... 

For example, chloroanilines and polychlorinated biphenyl congeners have been shown to alter by microbially-mediated reductive dehalogenation in sediment/water systems, yielding less chlorinated congeners [38,48,52,68,105, 116,119,369-371]. 

In activated sludge, 80.6% degraded after a 47-h time period (Pal et al., 1980). Chemical/Physical. Zhang and Rusling (1993) evaluated the bicontinuous microemulsion of surfactant/oil/water as a medium for the dechlorination of polychlorinated biphenyls by electrochemical catalytic reduction. The microemulsion (20 mL) contained didodecyldi-methylammonium bromide, dodecane, and water at 21, 57, and 22 wt %, respectively. The catalyst used was zinc phthalocyanine (2.5 nM). When PCB-1221 (72 mg), the emulsion and catalyst were subjected to a current of mA/cm on 11.2 cm lead electrode for 10 h, a dechlorination yield of 99% was achieved. Reaction products included a monochlorobiphenyl (0.9 mg), biphenyl, and reduced alkylbenzene derivatives. 

The potential of modern chemical instrumentation to detect and measure the conposition of coirplex mixtures has made it necessary to consider the use of methods of multivariable data analysis in the overall evaluation of environmental measurements. In a number of instances, the category (chemical class) of the compound that has given rise to a series of signals may be known but the specific entity responsible for a given signal may not be. This is true, for example, for the polychlorinated biphenyls (PCB s) in which the clean-up procedure and use of specific detectors eliminates most possibilities except PCB s. Such hierarchical procedures simplify the problem somewhat but it is still advantageous to apply data reduction methods during the course of the interpretation process. 

Polychlorinated biphenyls S,L Biooxidation after reductive or oxidative biodechlorination... 

The BioTrol soil washing system is a patented, water-based volume reduction process used to treat excavated soil. It separates slightly contaminated, coarse, washed soil particles from heavily contaminated fine soil particles. The process operates on the premise that (1) contaminants tend to be concentrated in the fine size fraction of soil (sUt, clay, and soil organic matter) and (2) contaminants associated with the coarse soil fraction (sand and gravel) are primarily surficial. The BioTrol soil washing system can be used to treat soils contaminated with petroleum hydrocarbons, pesticides, polychlorinated biphenyls (PCBs), various industrial chemicals, and metals. 

The XeChlor process is a reductive dechlorination process for the treatment of a wide array of organic halides, including conversion of polychlorinated biphenyls (PCBs) into biphenyl or dioxins into simple dibenzofuran. The dechlorination catalyst is prepared in situ from titanocene dichloride sodium borohydride is the reducing agent. 

Studying the electrochemical reduction of halogenated organic compounds has practical importance, especially related to organic syntheses [62], Moreover, the reductive cleavage of the C-X bond is applicable as a method to convert hazardous chlorinated compound for example, polychlorinated biphenyls (PCBs) to biphenyl by reducing in DMF at -2.8 V vs SCE [63],... 

Assaf-Anid, N.,Nies, L. Vogel, T. M. (1992). Reductive dechlorination cf a polychlorinated biphenyl congener and hexachlorobenzene by vitamin B12. Applied and Environmental Microbiology, 58, 1057-60. 

Alder, A. C., Haggblom, M. M., Oppenheimer, S. R. Young, L. Y. (1993). Reductive dechlorination of polychlorinated biphenyls in anaerobic sediments. Environmental Science Technology, 27, 530-8. 

Quensen, J.F. Ill, Tiedje, J.M. Boyd, S. A. (1988). Reductive dechlorination of polychlorinated biphenyls by anaerobic microorganisms from sediments. Science, 242, 752-4. 

Sokol, R. C., Kwon, O-S., Bethoney, C. M. Rhee, G-Y. (1994). Reductive dechlorination of polychlorinated biphenyls in St. Lawrence River sediments and variations in dechlorination characteristics. Environmental Science Technology, 28, 2054-64. 

Van Dort, H. Bedard, D. L. (1991)- Reductive ortho and meta dechlorination of polychlorinated biphenyl congeners by anaerobic microorganisms. Applied and Environmental Microbiology, 57, 1576-8. 

Zabik, M.E., Zabik, M.J., 1999. Polychlorinated biphenyls, polybrominated biphenyls, and dioxin reduction during processing/cooking food. In Jackson, L.S., Knize, M.G., Morgan, J.F. (Eds.), Impact of processing on food safety Advances in experimental medicine and biology. Plenum Press, New York, 459, pp. 213-231. 

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