Anaerobic biodegradation of known and potential gasoline oxygenates in the terrestrial subsurface

The octane enhancer tetraethyllead has been largely phased out of automobile fuels due to environmental and health concerns. Oxygenates such as methyl tert-butyl ether (MTBE), ethanol, methanol, and tert-butylalcohol provide both octane enhancement and oxygen content to gasolines. It is the authors' contention that the environmental and health risks associated with the use of gasoline oxygenates has not been fully evaluated since the fate of gasoline has not been taken into account. Gasoline is often spilled or leaks from storage facilities and contaminates surrounding environments, including aquifers. In the United States alone, tens of millions of gallons of gasoline may be released from storage tanks to the ground each year. They sought to (i) examine known and potential gasoline oxygenates for their susceptibility to anaerobic decay, (ii) identify structural features that tended to favor or retard the anaerobic destruction of these materials, and (iii) identify potential gasoline oxygenates which may be more environmentally acceptable than the additives currently employed. 31 refs., 1 tab.