Microbial degradation of alkylbenzenes under sulfate-reducing and methanogenic conditions. Final report, May 89-Apr 91

Technical Report · Mon Jul 01 04:00:00 EDT 1991

OSTI ID:5325785

Beller, H R; Edwards, E A; Grbic-Galic, D; Reinhard, M

Aquifer solids and soils obtained from various hydrocarbon-contaminated sites were used to investigate the ability of indigenous microorganisms to degrade monoaromatic hydrocarbons under strictly anaerobic conditions. In anaerobic microcosms inoculated with fuel-contaminated soil from the Patuxent River site, toluene degradation occurred concomitantly with sulfate reduction and ferric iron reduction. Similar results were obtained with suspended enrichments derived from the microcosms. Stoichiometric data and other observations suggested that sulfate reduction was closely linked to toluene degradation, whereas iron reduction was a secondary, potentially abiotic, reaction between ferric iron and biogenic hydrogen sulfide. The presence of millimolar concentrations of amorphous Fe(OH)3 in Patuxent River microcosms and enrichments either greatly facilitated the onset of toluene degradation or accelerated the rate once degradation had begun. Fermentative/methanogenic microcosms and enrichments that degraded toluene and o-xylene without added exogenous electron acceptors (except CO2) were developed from creosote-contaminated Pensacola samples. The microcosms initially underwent an acclimation lag of several months; however, once the degradation of aromatic hydrocarbons was initiated, it proceeded at a relatively rapid rate, and it was complete (resulting in mineralization to CO2 and CH4). Benzene, ethylbenzene, and p-xylene were not degraded.

• Research Organization: Stanford Univ., CA (United States). Dept. of Civil Engineering
• OSTI ID: 5325785
• Report Number(s): PB-91-212324/XAB; CNN: EPA-R-815721
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
560300 -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKYLATED AROMATICS
ANAEROBIC CONDITIONS
AROMATICS
BACTERIA
BIODEGRADATION
CHEMICAL REACTIONS
CONTAMINATION
CONTROL
DECOMPOSITION
ELEMENTS
ENVIRONMENTAL TRANSPORT
GROWTH
HYDROCARBONS
IRON
LAND POLLUTION CONTROL
MASS TRANSFER
METALS
MICROCOSMS
MICROORGANISMS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
POLLUTION CONTROL
SOILS
STOICHIOMETRY
STORAGE
SULFATE-REDUCING BACTERIA
SULFATES
SULFUR COMPOUNDS
TOLUENE
TRANSITION ELEMENTS
UNDERGROUND STORAGE
WATER POLLUTION CONTROL
XYLENES