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The Henrys Law constant was determined for methyl tert-butyl ether (MTBE) at four temperatures through a new, accurate, and experimentally simple method, based on the work of Gossett (Environ. Sci. Technol. 21:202-208, 1987). The constant was calculated to be 0.032 at 25 °C, suggesting that MTBE is more volatile than previously reported. Analysis of unpublished data collected earlier, using th...
Methyl-tert-butyl ether (MTBE) is a commonly used gasoline additive. Leaking underground storage tank systems, spills, and pipeline failures are the causes of reported groundwater contamination with MTBE. The impact of vegetation on MTBE plume transport in groundwater and volatilization was experimentally examined. The experimental system consists of six channels, five of which are planted with...
Methyl tert-butyl ether (MTBE) was originally introduced as an additive to increase octane number into gasoline in the 1970s. Its use was primarily as an octane enhancer to replace lead in gasoline. Later on, it was also used as an oxygenate, up to 15% v/v, to accomplish a cleaner burning fuel with reduced emissions of carbon monoxide and hydrocarbons. The problem with MTBE is that it has cause...
The structure and function of a microbial community capable of biodegrading methyl-tert-butyl ether (MTBE) was characterized using compound-specific stable isotope analysis (CSIA), clone libraries and stable isotope probing of proteins (Protein-SIP). The enrichment culture (US3-M), which originated from a gasoline-impacted site in the United States, has been enriched on MTBE as the sole carbon ...
195 INTRODUCTION In an attempt to reduce the environmental consequences associated with incomplete fuel combustion, the US Clean Air Act Amendments of 1990, required that oxygenates are added to reformulated gasoline. Since 1979, methyl tert butyl ether (MTBE) has been used in the USA as an octane enhancing replacement for lead, primarily in mid and high grade gasoline. It is the most commonly ...
Methyl tert-butyl ether ~MTBE! contamination in groundwater often coexists with benzene, toluene, ethylbenzene, and xylene ~BTEX! near the source of the plume. Tertiary butyl alcohol ~TBA! is a prevalent intermediate of MTBE degradation. Therefore, there is a significant potential for interference of MTBE and TBA degradation by the presence of BTEX whether treatment is in situ or ex situ. In th...
Aggregate (multiple pathway) exposures to methyl tertiary-butyl ether (MTBE) in air and water occur via dermal, inhalation, and oral routes. Previously, physiologically based pharmacokinetic (PBPK) models have been used to quantify the kinetic behavior of MTBE and its primary metabolite, tertiary-butyl alcohol (TBA), from inhalation exposures. However, the contribution of dermal and oral exposu...
Biodegradation of methyl tert-butyl ether (MTBE) by the hydrogen-oxidizing bacterium Hydrogenophaga flava ENV735 was evaluated. ENV735 grew slowly on MTBE or tert-butyl alcohol (TBA) as sole sources of carbon and energy, but growth on these substrates was greatly enhanced by the addition of a small amount of yeast extract. The addition of H(2) did not enhance or diminish MTBE degradation by the...
The massive production of methyl tert-butyl ether (MTBE), a primary constituent of reformulated gasoline, combined with its mobility, persistence and toxicity, makes it an important pollutant. It was considered recalcitrant until a few years ago, but recently MTBE biodegradation in aerobic conditions has been demonstrated with both mixed and pure cultures. Mixed cultures are generally the more ...
The occurrence of methyl tert-butyl ether (MTBE) in water from public wells in New Hampshire has increased steadily over the past several years. Using a laboratory reporting level of 0.2 microg/L, 40% of samples from public wells and 21% from private wells in southeast New Hampshire have measurable concentrations of MTBE. The rate of occurrence of MTBE varied significantly for public wells by e...
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