skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Reductive dehalogenation of polybrominated and polychlorinated biphenyls by anaerobic microorganisms from sediment

Miscellaneous ·
OSTI ID:7206993

Polychlorinated biphenyls (PCBs)and polybrominated biphenyls (PBBs) are stable industrial chemicals that consist of complex mixtures considered to be highly recalcitrant to biological degradation in the environment. Reductive dehalogenation is the only known biodegradation process for the more highly halogenated PCB and PBB mixtures. Studies were undertaken to: (1) examine in situ reductive debromination in sediments of the Pine River Reservoir, (2) compare the ability of microorganisms from PCB-contaminated and PBB-contaminated sediments to debrominate the commercial PBB mixture, Firemaster, (3) examine factors which might enhance reductive dehalogenation in sediments, (4) evaluate the role of sediment for dechlorinating microorganisms. Sediments in the heavily contaminated region of the Pine River have undergone little or no debromination. Anaerobic microorganisms previously shown to dechlorinate PCB mixtures were unable to dechlorinate Aroclor 1242 in the presence of Pine River sediments located close to the PBB manufacturing site. Microorganisms downstream of the heaviest contamination were able to debrominate Firemaster. Microorganisms from the Pine River (contaminated with Firemaster), Hudson River (contaminated with Aroclor 1242) and Silver Lake (contaminated with Aroclor 1260), removed 32%, 12%, and 3% of the meta plus para bromines, respectively, after 32 weeks. The Pine River inoculum removed an average of 1.25 bromines from the biphenyl molecule. When Firemaster was incubated with Hudson River microorganisms, 17% of the meta and para bromines were removed after 16 weeks, and additional debromination products, 2-bromobiphenyl and biphenyl, were detected suggesting ortho debromination. A PCB enrichment culture was established using pyruvate as an electron donor and Aroclor 1242 as the electron acceptor. Three Michigan surface soils, Pine River sediments, and ashed sediment supported reductive dechlorination of Aroclor 1242 by Hudson River microorganisms.

Research Organization:
Michigan State Univ., East Lansing, MI (United States)
OSTI ID:
7206993
Resource Relation:
Other Information: Thesis (Ph.D.)
Country of Publication:
United States
Language:
English