CH₃C(=O)-CH₂CH₂ also known as methyl ethyl ketone, 2-butanone is a product of the manufacturing of paints, glues, and other finishes because of its dissolving ability. A byproduct in the exhaust of automobiles, 2-butanone can easily evaporate into the atmosphere. It has been detected in both indoor and outdoor air. While in outdoor air it is produced by the photoxidation of certain air pollutants, such as butane and other hydrocarbons. Is known to have negative health effects when breathed in at high concentrations.