Material Safety Data Sheet (MSDS) for Methyl Ethyl Ketone (MEK)

Identification

Product Name: Methyl Ethyl Ketone
Synonyms: 2-Butanone, MEK, Methyl Acetone
Chemical Formula: C4H8O
CAS Number: 78-93-3
Intended Use: Solvent in coatings, adhesives, printing inks, cleaning agents
Manufacturer: Refer to company information on product label
Emergency Contact: Refer to local emergency response and manufacturer's emergency line

Hazard Identification

GHS Classification: Flammable liquids (Category 2), Eye irritation (Category 2), Specific target organ toxicity - single exposure (Category 3), Narcotic effects
Pictograms: Flame, Exclamation Mark
Signal Word: Danger
Hazard Statements: Highly flammable liquid and vapor. Causes serious eye irritation. May cause drowsiness or dizziness. Vapors may cause flash fire.
Precautionary Statements: Keep away from heat, sparks, open flames, and hot surfaces. Use explosion-proof equipment. Ground and bond container and receiving equipment. Wash thoroughly after handling. Avoid breathing mist, vapors, or spray. Use only outdoors or in a well-ventilated area. Wear protective gloves, clothing, and eye protection.
Hazard Routes: Inhalation, skin absorption, and ingestion

Composition / Information on Ingredients

Chemical Name: Methyl Ethyl Ketone
Synonyms: 2-Butanone
Concentration: 99% or higher
Common Impurities: Water (<0.5%), acetone, other minor ketones (<0.1%)
CAS Number: 78-93-3

First Aid Measures

Inhalation: Remove person to fresh air immediately. If breathing is labored or respiratory symptoms arise, get medical attention.
Skin Contact: Rinse skin thoroughly with water for at least 15 minutes. Remove contaminated clothing and shoes, wash before reuse.
Eye Contact: Flush eyes with plenty of water for several minutes holding eyelids open. Remove contact lenses if present and easy to do. Seek medical advice if irritation persists.
Ingestion: Do not induce vomiting. Rinse mouth with water. Seek immediate medical attention.
General: Symptoms include headache, drowsiness, eye and respiratory irritation, nausea.

Fire-Fighting Measures

Suitable Extinguishing Media: Alcohol-resistant foam, dry chemical, carbon dioxide (CO2), water mist (use water spray to cool containers).
Unsuitable Extinguishing Agents: Straight water streams may spread fire.
Specific Hazards: Vapors may ignite explosively. Containers may rupture if exposed to heat. Forms explosive mixtures with air.
Firefighter Protection: Firefighters use self-contained breathing apparatus and proper protective gear.
Combustion Products: Carbon monoxide, carbon dioxide, unidentified toxic compounds.
Explosion Data: Vapors are heavier than air and may spread along floors to distant ignition sources.

Accidental Release Measures

Personal Precautions: Evacuate area, eliminate all ignition sources. Ventilate closed spaces. Wear protective equipment including gloves, goggles, and appropriate respirator.
Environmental Precautions: Avoid discharge to drains, sewers, and watercourses. Prevent spread of spillage.
Methods for Cleanup: Contain with earth, sand, or other inert material. Collect using non-sparking tools. Place waste into properly labeled containers for disposal. Do not wash away with water.
Decontamination: Wash spill site after cleanup is complete.

Handling and Storage

Handling: Use only in well-ventilated areas. Avoid breathing vapors and prevent skin and eye contact. Keep away from sources of ignition—no smoking. Use non-sparking tools and equipment. Do not eat, drink, or smoke in work areas. Wash hands thoroughly after handling.
Storage: Store in tightly closed containers in a cool, dry, and well-ventilated area away from incompatible materials such as oxidizers, acids, bases. Ground and bond storage containers. Use flame-proof lighting and electrical equipment in storage area. Keep containers out of sunlight and away from direct heat. Segregate from foodstuffs and animal feed.

Exposure Controls and Personal Protection

Occupational Exposure Limits: OSHA PEL: 200 ppm (TWA); ACGIH TLV: 200 ppm (TWA), 300 ppm (STEL)
Engineering Controls: Use of local exhaust ventilation or general dilution ventilation to control airborne concentrations below exposure limits.
Personal Protective Equipment (PPE): Chemical-resistant gloves such as nitrile, safety goggles or face shields, flame-resistant clothing, and approved respiratory protection in case of inadequate ventilation or airborne concentrations exceed permissible limits.
Hygiene: Wash hands and face after handling and before eating, drinking, or using restrooms.

Physical and Chemical Properties

Appearance: Colorless liquid
Odor: Sweet, sharp, acetone-like
Boiling Point: 79.6°C (175.3°F)
Melting Point: -86°C (-123°F)
Flash Point: -6°C (21°F) (closed cup)
Evaporation Rate: 2.7 (butyl acetate = 1)
Vapor Pressure: 71 mm Hg at 20°C
Vapor Density: 2.5 (air = 1)
Specific Gravity: 0.805 at 20°C (water = 1)
Solubility: Soluble in water (29 g/100 mL at 20°C), miscible with alcohol, ether
pH: Neutral
Partition Coefficient (n-octanol/water): log Pow = 0.29
Autoignition Temperature: 404°C (759°F)
Explosive Limits: LEL: 1.8%, UEL: 11.5%

Stability and Reactivity

Chemical Stability: Stable under recommended storage conditions.
Possible Hazardous Reactions: Can form explosive peroxides with prolonged exposure to air. May react vigorously with oxidizing agents.
Conditions to Avoid: Heat, sparks, open flame, sunlight, static discharge, air exposure without inhibitor.
Incompatible Materials: Strong oxidizing agents, acids, alkalis, halogens.
Hazardous Decomposition Products: Carbon monoxide, carbon dioxide, potentially toxic fumes.
Polymerization: Will not occur under normal conditions.

Toxicological Information

Likely Routes of Exposure: Inhalation, skin and eye contact, ingestion.
Acute Toxicity: Oral LD50 (rat): 2,730 mg/kg; Dermal LD50 (rabbit): >5,000 mg/kg; Inhalation LC50 (rat, 4h): 11,700 ppm
Effects of Short-Term Exposure: Irritating to eyes, may cause skin dryness or cracking, may cause dizziness, weakness, headache, drowsiness, and in high concentrations, nausea and respiratory tract irritation.
Effects of Long-Term Exposure: Prolonged or repeated skin exposure can cause dermatitis, repeated occupational overexposures can affect nervous system functions.
Carcinogenicity: Not classified as carcinogenic by IARC, NTP, OSHA.
Mutagenicity/Teratogenicity: No evidence found in animal or human studies for mutagenic or teratogenic effects.
Sensitization: Not a known skin or respiratory sensitizer.

Ecological Information

Environmental Fate: Readily biodegradable in air and water. Volatilizes rapidly from soil and surface water.
Bioaccumulation: Low potential for bioaccumulation (log Pow<1).
Ecotoxicity: Fish LC50 (fathead minnow, 96h): 3,169 mg/L; Daphnia EC50 (48h): 5,355 mg/L; Algae EC50: 4,000 mg/L
Other Adverse Effects: Can contribute to photochemical smog production. Spills may contaminate groundwater. Not likely to persist or biomagnify in food chains.
Aquatic Toxicity: Not classified as highly toxic to aquatic life.

Disposal Considerations

Waste Disposal Method: Collect and place in suitable, properly labeled containers for licensed chemical waste disposal. Do not dump uncontrolled into the environment. Disposal must comply with local, regional, national, and international regulations.
Contaminated Packaging: Containers must be completely emptied before disposal. Dispose drums and containers through authorized waste disposal contractor.
Special Precautions: Do not allow residue or large amounts to reach soil, surface, or groundwater directly.

Transport Information

UN Number: UN1193
Proper Shipping Name: Methyl Ethyl Ketone
Transport Hazard Class: 3 (Flammable liquids)
Packing Group: II
Label: Flammable Liquid
Special Provisions: Keep containers upright and tightly closed. Ship in accordance with local transport regulations. Emergency Guide: 127 (North America Emergency Response Guidebook).
Marine Pollutant: Not regulated as marine pollutant.
IMDG, ICAO/IATA, RID/ADR: Regulated for air, sea, and land transport under relevant laws.

Regulatory Information

OSHA: Listed hazardous chemical; subject to workplace chemical safety standards.
TSCA: Listed on the US Toxic Substances Control Act Inventory.
SARA 302: Not listed as extremely hazardous.
SARA 313: Subject to reporting requirements for certain uses.
California Proposition 65: Not listed.
Canada (WHMIS): Classified as Class B2 (Flammable Liquids), Class D2B (Toxic Material Causing Other Toxic Effects).
EU Regulations: EC Index No. 606-002-00-3.
REACH Registration: Registered substance under EU REACH.
Other International Regulations: Conforms to applicable global chemical control legislation including Japan (ENCS), Australia (AICS), Korea (KECL), and China (IECSC).