Methyl Ethyl Ketone

1Identification

Name

Methyl Ethyl Ketone

IUPAC name

butan-2-one

CAS number

78-93-3

EC number

201-159-0

Molecular formula

C4H8O

Molecular weight

72.11 g/mol

InChIKey

ZWEHNKRNPOVVGH-UHFFFAOYSA-N

SMILES

CCC(=O)C

PubChem CID

6569

Synonyms

2-Butanone, METHYL ETHYL KETONE, Butan-2-one, Butanone, Ethyl methyl ketone, Methylethyl ketone, Meetco, Methyl acetone, Methylethylketone, 3-Butanone, Ethylmethylketon, Aethylmethylketon, Butanone 2, Acetone, methyl-

Recommended uses

• The primary use of methyl ethyl ketone is as a solvent in processes involving gums, resins, cellulose acetate, and cellulose nitrate.
  EPA Hazardous Air Pollutants
• Used as a solvent for surface coatings, oils, resins, artificial leather, rubbers, and glues; usually found in mixtures with other solvents; It occurs naturally in food at low concentrations. [ACGIH]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Semiconductor Manufacturing [Category: Industry] Painting (Solvents) [Category: Paint] Working with Glues and Adhesives [Category: Other]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Polymerization promoter Dispersing agent Solvent CBI Other Binder Fuel Heat transferring agent Cleaning agent Waterproofing agent Not Known or Reasonably Ascertainable Diluent Etching agent Adhesion/cohesion promoter Hardener Intermediate Surface modifier
  EPA Chemical Data Reporting (CDR)
• Binder Solvent Heat transferring agent Surfactant (surface active agent) Not Known or Reasonably Ascertainable Diluent Surface modifier Adhesion/cohesion promoter Etching agent Hardener
  EPA Chemical Data Reporting (CDR)

Use categories: Chemical Classes -> Volatile organic compounds · EPA Safer Chemical Functional Use Classes -> Specialized Industrial Chemicals · Safer Chemical Classes -> Yellow triangle - The chemical has met Safer Choice Criteria for its functional ingredient-class, but has some hazard profile issues · Fragrance Ingredients

Description

• 2-Butanone is a manufactured chemical but it is also present in the environment from natural sources. It is a colorless liquid with a sharp, sweet odor. It is also known as methyl ethyl ketone (MEK). 2-Butanone is produced in large quantities. Nearly half of its use is in paints and other coatings because it will quickly evaporate into the air and it dissolves many substances. It is also used in glues and as a cleaning agent. 2-Butanone occurs as a natural product. It is made by some trees and found in some fruits and vegetables in small amounts. It is also released to the air from car and truck exhausts.
  Agency for Toxic Substances and Disease Registry (ATSDR)
• Methyl ethyl ketone appears as colorless fairly volatile liquid with a pleasant pungent odor. Flash point 20 °F. Vapors heavier than air. Does not react with water or many common materials. Stable in normal transportation. Irritates the nose, eyes, and throat. Combustion may produce toxic materials. Density 6.7 lb / gal. Used as a solvent, for making other chemicals, and for production of wax from petroleum.
  CAMEO Chemicals
• Butan-2-one is a dialkyl ketone that is a four-carbon ketone carrying a single keto- group at position C-2. It has a role as a polar aprotic solvent and a bacterial metabolite. It is a volatile organic compound, a dialkyl ketone, a butanone and a methyl ketone.
  ChEBI

2Hazard identification

Signal word

Danger

Pictograms

GHS02, GHS07

Classification source

Regulation (EC) No 1272/2008 of the European Parliament and of the Council

Precautionary statements

Other reported classifications

6 classification records exist across sources. Differences usually reflect purity, physical form or impurities.

NFPA 704 rating

• 1 - Materials that, under emergency conditions, can cause significant irritation.
  Hazardous Substances Data Bank (HSDB)
• 3 - Liquids and solids that can be ignited under almost all ambient temperature conditions. Materials produce hazardous atmospheres with air under almost all ambient temperatures or, though unaffected by ambient temperatures, are readily ignited under almost all conditions.
  Hazardous Substances Data Bank (HSDB)
• 0 - Materials that in themselves are normally stable, even under fire conditions.
  Hazardous Substances Data Bank (HSDB)

Health hazards

• Liquid causes eye burn. Vapor irritates eyes, nose, and throat; can cause headache, dizziness, nausea, weakness, and loss of consciousness. (USCG, 1999)
  CAMEO Chemicals
• · Inhalation or contact with material may irritate or burn skin and eyes. · Fire may produce irritating, corrosive and/or toxic gases. · Vapors may cause dizziness or asphyxiation, especially when in closed or confined areas. · Runoff from fire control or dilution water may cause environmental contamination.
  Emergency Response Guidebook (ERG)

Fire hazards

• Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. CAUTION: Ethanol (UN1170) can burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.) Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.). Vapor explosion hazard indoors, outdoors or in sewers. Those substances designated with a (P) may polymerize explosively when heated or involved in a fire.
  CAMEO Chemicals
• · HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. CAUTION: Ethanol (UN1170) can burn with an invisible flame. Use an alternate method of detection (thermal camera, broom handle, etc.) · Vapors may form explosive mixtures with air. · Vapors may travel to source of ignition and flash back. · Most vapors are heavier than air. They will spread along the ground and collect in low or confined areas (sewers, basements, tanks, etc.). · Vapor explosion hazard indoors, outdoors or in sewers. · Those substances designated with a (P) may polymerize explosively when heated or involved in a fire. · Runoff to sewer may create fire or explosion hazard.
  Emergency Response Guidebook (ERG)
• Highly flammable. Vapour/air mixtures are explosive.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Hazards summary

• 2-Butanone is a manufactured chemical but it is also present in the environment from natural sources. It is a colorless liquid with a sharp, sweet odor. It is also known as methyl ethyl ketone (MEK). 2-Butanone is produced in large quantities. Nearly half of its use is in paints and other coatings because it will quickly evaporate into the air and it dissolves many substances. It is also used in glues and as a cleaning agent. 2-Butanone occurs as a natural product. It is made by some trees and found in some fruits and vegetables in small amounts. It is also released to the air from car and truck exhausts.
  Agency for Toxic Substances and Disease Registry (ATSDR)
• Methyl ethyl ketone is used as a solvent. Acute (short-term) inhalation exposure to methyl ethyl ketone in humans results in irritation to the eyes, nose, and throat. Limited information is available on the chronic (long-term) effects of methyl ethyl ketone in humans. Chronic inhalation studies in animals have reported slight neurological, liver, kidney, and respiratory effects. No information is available on the developmental, reproductive, or carcinogenic effects of methyl ethyl ketone in humans. Developmental effects, including decreased fetal weight and fetal malformations, have been reported in mice and rats exposed to methyl ethyl ketone via inhalation and ingestion.
  EPA Hazardous Air Pollutants

3Composition / information on ingredients

This page describes the pure substance. Commercial products may be solutions or mixtures. Check Section 3 of your supplier's SDS for concentrations and other ingredients.

4First-aid measures

• EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop. SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water.
  CAMEO Chemicals
• General First Aid: · Call 911 or emergency medical service. · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination. · Move victim to fresh air if it can be done safely. · Administer oxygen if breathing is difficult. · If victim is not breathing: -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance. -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).
  Emergency Response Guidebook (ERG)
• (General first aid procedures) Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately. Skin: Water wash immediately - If this chemical contacts the skin, immediately wash the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and wash the skin with water. If symptoms occur after washing, get medical attention immediately. Breathing: Fresh air Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.
  The National Institute for Occupational Safety and Health (NIOSH)

Symptoms of exposure

• Cough. Headache. Dizziness. Nausea. Vomiting. Drowsiness. Numbness. Laboured breathing.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Dry skin.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness. Pain.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• In case of fire: keep drums, etc., cool by spraying with water. Powder, AFFF, foam, carbon dioxide.
  Hazardous Substances Data Bank (HSDB)
• Alc foam, dry chemical, or carbon dioxide
  Hazardous Substances Data Bank (HSDB)
• If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped or safely confined. Use water in flooding quantities as fog. Solid streams of water may be ineffective. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible. Use alcohol foam, dry chemical or carbon dioxide.
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Isolation and evacuation

• Excerpt from ERG Guide 127 [Flammable Liquids (Water-Miscible)]: IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area for at least 50 meters (150 feet) in all directions. LARGE SPILL: Consider initial downwind evacuation for at least 300 meters (1000 feet). FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)
  CAMEO Chemicals
• Immediate precautionary measure · Isolate spill or leak area for at least 50 meters (150 feet) in all directions. Large Spill · Consider initial downwind evacuation for at least 300 meters (1000 feet). Fire · If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions.
  Emergency Response Guidebook (ERG)

Spill cleanup

• Personal protection: self-contained breathing apparatus. Do NOT wash away into sewer. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in sand or inert absorbent. Then store and dispose of according to local regulations.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Evacuate and restrict persons not wearing protective equipment from area of spill or leak until cleanup is complete. Remove all ignition sources. Establish forced ventilation to keep levels below explosive limit. Absorb liquids in vermiculite, dry sand, earth, peat, carbon, or similar material and deposit in sealed containers. Oil-skimming equipment and sorbent foams can be applied to slick if done immediately. Keep this chemical out of a confined space ... because of the possibility of an explosion ... It may be necessary to contain and dispose of this chemical as a hazardous waste.
  Hazardous Substances Data Bank (HSDB)
• Environmental considerations-air spill: Apply water spray or mist to knock down vapors
  Hazardous Substances Data Bank (HSDB)
• Environmental considerations-water spill: Use natural barriers or oil spill control booms to limit spill travel. Remove trapped material with suction hoses.
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Fireproof. Separated from strong oxidants and strong acids. Cool. Well closed. Store in an area without drain or sewer access.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Methyl ethyl ketone must be stored to avoid contact with strong oxidizers (such as chlorine, bromine, and fluorine) since violent reactions may occur. Store in tightly closed containers in a cool, well ventilated area away from sources of heat, sparks, or flame. Sources of ignition such as smoking and open flames are prohibited where methyl ethyl ketone is handled, used or stored in a manner that could create a potential fire or explosion hazard. Metal containers involving the transfer of 5 gallons or more of diethyl ketone should be grounded and bonded. Drums must be equipped with self-closing valves, pressure vacuum bungs, and flame arresters.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

Personal protective equipment

• Excerpt from NIOSH Pocket Guide for 2-Butanone: Skin: PREVENT SKIN CONTACT - Wear appropriate personal protective clothing to prevent skin contact. Eyes: PREVENT EYE CONTACT - Wear appropriate eye protection to prevent eye contact. Wash skin: WHEN CONTAMINATED - The worker should immediately wash the skin when it becomes contaminated. Remove: WHEN WET (FLAMMABLE) - Work clothing that becomes wet should be immediately removed due to its flammability hazard (i.e., for liquids with a flash point <100 °F). Change: No recommendation is made specifying the need for the worker to change clothing after the workshift.
  CAMEO Chemicals
• Skin contact should be avoided by the use of protective gloves; goggles may also be necessary to prevent eye contact. /Ketones/
  Hazardous Substances Data Bank (HSDB)
• Breakthrough times greater than one hour reported by (normally) two or more testers were found for butyl rubber gloves.
  Hazardous Substances Data Bank (HSDB)
• Breakthrough times less (usually significantly less) than one hour reported by (normally) two or more testers were found for natural rubber latex gloves, unsupported; neoprene/natural rubber blend; nitrile rubber glove, unsupported; polyethylene glove; polyvinyl alcohol glove, supported; polyvinyl chloride glove, unsupported; and viton, raw material.
  Hazardous Substances Data Bank (HSDB)

Respirator recommendations

• NIOSH/OSHA Up to 3000 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode (APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s) (APF = 50) Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s) (APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister (APF = 50) Any self-contained breathing apparatus with a full facepiece (APF = 50) Any supplied-air respirator with a full facepiece Emergency or planned entry into unknown concentrations or IDLH conditions: (APF = 10,000) Any self-contained breathing apparatus that has a full facepiece…
  The National Institute for Occupational Safety and Health (NIOSH)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• METHYL ETHYL KETONE is explosive in the form of vapor when exposed to heat, flame or sparks. Ignition on contact with potassium tert-butoxide. Reactive with strong oxidizing materials, and will dissolve or soften some plastics. Mixture with 2-propanol will form explosive peroxides during storage. Vigorous reaction with chloroform in the presence of alkali (sodium hydroxide, potassium hydroxide), chlorosulfonic acid, fuming sulfuric acid (oleum) [Lewis, 3rd ed., 1993, p. 855]. Reaction with hydrogen peroxide in the presence of nitric acid forms heat- and shock-sensitive explosive acetone peroxides. [Bjorklund, G. H. et al., Trans. R. Soc. Can, 1950, 44, p. 25].
  CAMEO Chemicals
• Highly flammable. Soluble in water.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Reacts violently with strong oxidants and inorganic acids causing fire and explosion hazard. Attacks some plastic.
  Hazardous Substances Data Bank (HSDB)
• Incompatible with chloroform, hydrogen peroxide, nitric acid, potassium t-butoxide, and 2-propanol.
  Hazardous Substances Data Bank (HSDB)
• forms exposive mixture with air. Violent reaction with strong oxidizers, amines, ammonia, inorganic acids. caustics, isocyanates, pyridines. Incompatible with potassium teret-butoxide, 2-propanol, chlorosulfonice acid, oleum. Attacks some plastics.
  Hazardous Substances Data Bank (HSDB)

Chemical stability

• Stability during transport: stable
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Target organs

• Neurological (Nervous System), Ocular (Eyes), Respiratory (From the Nose to the Lungs)
  Agency for Toxic Substances and Disease Registry (ATSDR)
• Developmental Musculoskeletal
  EPA Integrated Risk Information System (IRIS)

Short-term exposure effects

• The substance is irritating to the eyes and respiratory tract. The substance may cause effects on the central nervous system. Exposure could cause unconsciousness. If swallowed the substance easily enters the airways and could result in aspiration pneumonitis.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Long-term exposure effects

• The substance defats the skin, which may cause dryness or cracking. Animal tests show that this substance possibly causes toxicity to human reproduction or development.
  ILO-WHO International Chemical Safety Cards (ICSCs)

12Ecological information

Not available in the public sources we compile. Check Section 12 of the supplier's SDS.

13Disposal considerations

• Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste numbers U159, D035 and F005, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.
  Hazardous Substances Data Bank (HSDB)
• Incineration. Recommendable methods: Incineration, open burning, use as a fuel, evaporation, discharge to sewer. Peer-review: Potentially contains peroxides which may be explosive. Evaporate small amt only. (Peer-review conclusions of an IRPTC expert consultation (May 1985))
  Hazardous Substances Data Bank (HSDB)
• A good candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids. A good candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °C and residence times of seconds for liquids and gases, and hours for solids. A good candidate for liquid injection incineration at a temperature range of 650 to 1,600 °C and a residence time of 0.1 to 2 seconds.
  Hazardous Substances Data Bank (HSDB)

14Transport information

UN number: UN 1193

Shipping name

• UN 1193; Ethyl methyl ketone or Methyl ethyl ketone
  Hazardous Substances Data Bank (HSDB)
• IMO 3; Ethyl methyl ketone or Methyl ethyl ketone
  Hazardous Substances Data Bank (HSDB)

DOT hazard class

• Ethyl methyl ketone or Methyl ethyl ketone
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• UN1193
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• Class 3 Flammable and combustible liquid (49 eCFR § 173.120)
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172

DOT label

• Flammable Liquid
  CAMEO Chemicals

UN classification

• UN Hazard Class: 3; UN Pack Group: II
  ILO-WHO International Chemical Safety Cards (ICSCs)

Emergency Response Guidebook

• 1193 127
  Emergency Response Guidebook (ERG)

How DOT hazard classes work →

15Regulatory information

• This action promulgates standards of performance for equipment leaks of Volatile Organic Compounds (VOC) in the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The intended effect of these standards is to require all newly constructed, modified, and reconstructed SOCMI process units to use the best demonstrated system of continuous emission reduction for equipment leaks of VOC, considering costs, non air quality health and environmental impact and energy requirements. Methyl ethyl ketone is produced, as an intermediate or final product, by process units covered under this subpart.
  Hazardous Substances Data Bank (HSDB)
• Residues of methyl ethyl ketone are exempted from the requirement of a tolerance when used as a surfactant in accordance with good agricultural practice as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops only.
  Hazardous Substances Data Bank (HSDB)
• Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 5000 lb or 2270 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).
  Hazardous Substances Data Bank (HSDB)
• Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Methyl ethyl ketone is included on this list. Effective date 10/4/1982, Sunset date 10/4/1992.
  Hazardous Substances Data Bank (HSDB)
• U159; As stipulated in 40 CFR 261.33, when 2-butanone, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to Federal and/or State hazardous waste regulations. Also defined as a hazardous waste is any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5).
  Hazardous Substances Data Bank (HSDB)
• Methyl ethyl ketone is an indirect food additive for use only as a component of adhesives.
  Hazardous Substances Data Bank (HSDB)

Overview of SDS regulations (OSHA HazCom, WHMIS, REACH/CLP) →

16Other information

Compiled from PubChem CID 6569 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.