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Methyl Ethyl Ketone


CAS No. 78-93-3

Methyl ethyl ketone (C4H8O or CH3CH3COCH2CH3) is a colorless, flammable liquid with a sharp odor. It can be harmful to the eyes, skin, and if inhaled or swallowed. Workers may be harmed from exposure to methyl ethyl ketone. The level of exposure depends upon the dose, duration, and work being done.

Methyl ethyl ketone is used in many industries. It is used as a solvent and in the manufacture of synthetic rubber, paraffin wax, and to make other chemical products. Some examples of workers at risk of being exposed to methyl ethyl ketone include the following:

  • Workers who work in printing plants
  • Employees exposed to certain paints, coatings, or glues
  • Workers who work in shoe and sporting goods factories
  • Manufacturing workers involved in making synthetic rubber products

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses methyl ethyl ketone, please read chemical labels and the accompanying Safety Data Sheets for hazard information. Visit NIOSH’s page on Managing Chemical Safety in the Workplace to learn more about controlling chemical workplace exposures.

The following resources provide information about occupational exposure to methyl ethyl ketone. Useful search terms for methyl ethyl ketone include “2-butanone,” “MEK,” “methyl acetone,” and “methyl ethyl ketone.”

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