64 research outputs found

    Biotechnology for the Environment

    Get PDF
    Joint US-European Community Pilot Program support for short-term exchanges of early career scientists

    The Toxicity of Selected Gasoline Components to Glucose Methanogenesis by Aquifer Microorganisms

    No full text
    Six model hydrocarbons, representing various classes of chemicals found in gasoline, and methyl ethyl ketone, were assayed for their inhibitory effect on glucose methanogenesis in slurries prepared from aquifer sediments and ground water. Biogas (CH4 and CO2) production was monitored with an automated pressure transducer system. Benzene, 1-methyl naphthalene, and methyltert-butyl ether (MTBE) were found to have no inhibitory influence on biogas production rates at concentrations up to 71·7 mg/L. Similarly, octane, cyclohexane, indan, and methyl ethylketone (MEK) were found to have only marginal negative effects on the rate of biogas production in aquifer slurries, at concentrations ranging from 51·7 to 72·1 mg/L. Thus, gasoline components had low apparent toxicities to microorganisms responsible for glucose methanogenesis in aquifier slurries. As the concentrations of the assayed hydrocarbons are about 100 times those typically reported after an aquifer has been contaminated with gasoline, it is unlikely that individual hydrocarbons will substantially impact anaerobic metabolic processes

    Reductive Dehalogenation of a Nitrogen Heterocyclic Herbicide in Anoxic Aquifer Slurries

    No full text
    We studied the metabolic fate of bromacil in anaerobic aquifer slurries held under denitrifying, sulfate-reducing, or methanogenic conditions. Liquid chromatograhy-mass spectrometry of the slurries confirmed that bromacil was debrominated under methanogenic conditions but was not degraded under the other incubation conditions. This finding extends the range of aryl reductive dehalogenation reactions to include nitrogen heterocyclic compounds

    Anaerobic Biodegradation of Known and Potential Gasoline Oxygenates in the Terrestrial Subsurface

    No full text
    The octane enhancer tetraethyllead has been largely phased out of automobile fuels due to environmental and health concerns, and recent U.S. legislation mandates the reformulation of gasoline to increase its oxygen content. Oxygenates such as methyl tert-butyl ether (MTBE), ethanol, methanol, and tert-butyl alcohol provide both octane enhancement and oxygen content to gasolines. The use of such additives is believed to be environmentally acceptable since oxygenated fuels reduce the impact of hydrocarbon combustion on the atmosphere
    corecore