Methyl tert-Butyl Ether (MTBE)

Methyl tert-Butyl Ether (MTBE) is a chemical compound used as an additive in gasoline. It acts as an oxygenating agent to raise the octane number and prevent engine knocking. Low levels of MTBE have been used in gasoline since 1979 to replace lead as an octane enhancer. In some areas of the US, higher levels of MTBE are used as part of the Clean Air Act, to reduce harmful tailpipe emissions from motor vehicles. The oxygen dilutes or displaces aromatic and sulfur compounds found in gasoline, and improves combustion. MTBE is often the oxygenate of choice due to its blending properties, relatively low cost, and ease of transportation.

Although MTBE is not recognized as harmful to the refinery worker or the community in it’s common form, it does pose a risk to the environment from leaking underground storage tanks (UST’s) and pipelines. MTBE, when released into the environment, dissolves easily in water and often brings along other harmful contaminants with it such as BTEX compounds. At this time, there is no conclusive evidence to suggest that inhalation of MTBE poses a human risk. For more information on MTBE in the environment, visit the EPA’s website: www.epa.gov/mtbe