A long-term study of anaerobic dechlorination of PCB congeners by sediment microorganisms pathways and mass balance

Journal Article · Fri Oct 01 00:00:00 EDT 1993 · Environmental Toxicology and Chemistry; (United States)

DOI:https://doi.org/10.1002/etc.5620121009· OSTI ID:5696441

Rhee, G Y; Sokol, R C; Bush, B ^[1]; Bethoney, C M ^[2]

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1. State Univ. of New York, Albany, NY (United States). Wadsworth Center for Labs. and Research
2. State Univ. of New York, Albany, NY (United States). School of Public Health, New York State Dept. of Health

Reductive dechlorination of PCBs by Hudson River sediment microorganisms was investigated using individual congeners, 2,3,4,2[prime],4[prime],5[prime]-, 2,4,5,2[prime],4[prime],5[prime]-, 2,3,4,5,6-, 2,4,2[prime],4[prime]-, and 3,4,3[prime],4[prime]-chlorobiphenyls (CBPs) in long-term studies lasting 15 to 20 months. The dechlorination of 2,3,4,2[prime],4[prime],5[prime]-CBP yielded 2,4,5,2[prime],4[prime]-, 2,4,2[prime],4[prime]-, 2,4,2[prime],5[prime]-, and 2,4,2[prime],5[prime]-, and 2,4,2[prime]-CBPs; notably absent was 2,2[prime]-CBP. Yet, the total molar concentration of all congeners decreased with time and at 15 months accounted for only 25% of the initial concentration of the parent compound. 2,3,4,5,6-CBP produced 2,3,5,6-, 2,4,6-, and 2,6-CBPs. At 15 months the sum of all congeners accounted for only about 50% of the initial amount of the parent congener. On the other hand, 2,4,5,2[prime],4[prime],5[prime]-CBP yielded six daughter products, including 2,2[prime]-CBP, and did not show any decrease in total molar concentration even at 20 months. 2,4,2[prime],4[prime]-CBP did not show any change at 15 months. These results indicate that anaerobic PCB biotransformation may include mechanisms other than dechlorination and that the mechanisms are congener dependent. Biphenyl was detected with 3,4,3[prime],4[prime]-CBP, indicating complete dechlorination; however, it accounted for <10% of the total molar loss. [sup 14]C-labeled tracer of this congener showed that all radioactivity was in the hexane fraction, suggesting that transformation products were hydrophobic.

• OSTI ID: 5696441
• Journal Information: Environmental Toxicology and Chemistry; (United States), Vol. 12:10; ISSN 0730-7268
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
HUDSON RIVER
WATER POLLUTION
POLYCHLORINATED BIPHENYLS
BIODEGRADATION
SEDIMENTS
DECONTAMINATION
ANAEROBIC DIGESTION
DECHLORINATION
ECOLOGICAL CONCENTRATION
AROMATICS
BIOCONVERSION
CHEMICAL REACTIONS
CHLORINATED AROMATIC HYDROCARBONS
CLEANING
DECOMPOSITION
DEHALOGENATION
DIGESTION
HALOGENATED AROMATIC HYDROCARBONS
MANAGEMENT
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
POLLUTION
PROCESSING
RIVERS
STREAMS
SURFACE WATERS
WASTE MANAGEMENT
WASTE PROCESSING
540350* - Environment
Aquatic- Site Resource &amp; Use Studies- (1990-)
560300 - Chemicals Metabolism &amp; Toxicology