Knowledge
Material Safety Data Sheet: Acetonitrile (MeCN)
Identification
Chemical Name: Acetonitrile
Common Names: Methyl cyanide, Cyanomethane
CAS Number: 75-05-8
Molecular Formula: C2H3N
Recommended Use: Laboratory solvent, chemical synthesis, pharmaceuticals
Manufacturer/Supplier Details: Detailed contact information of manufacturer, emergency telephone available 24/7
Synonyms: Ethanenitrile, Methanecarbonitrile
UN Number: 1648
Emergency Contact: Chemtrec, local medical emergency service
Hazard Identification
GHS Classification: Flammable Liquid (Category 2), Acute Toxicity Oral (Category 4), Acute Toxicity Dermal (Category 4), Acute Toxicity Inhalation (Category 4), Eye Irritant (Category 2A)
Pictograms: Flame, Exclamation mark, Health hazard
Signal Word: Danger
Hazard Statements: Highly flammable liquid and vapor. Harmful if swallowed, in contact with skin, or inhaled. Causes serious eye irritation. May cause drowsiness or dizziness.
Precautionary Statements: Keep away from heat, sparks, open flames. Wear protective gloves and eye protection. Avoid breathing vapors. Use only outdoors or in well-ventilated area
Routes of Exposure: Skin, ingestion, inhalation, eyes
EHS Regulation: Classified as hazardous under OSHA, WHMIS, REACH, and GHS standards
Chronic Effects: Central nervous system depression, liver and kidney toxicity with prolonged exposure
Composition / Information on Ingredients
Substance: Acetonitrile
Common Name: Acetonitrile
Percent Content: Typically >99% by weight
Impurities: May contain low levels of water or other nitriles
Ingredient Classification: Cyanide compound
Other Additives: None in standard analytical and industrial grades
Purity Disclosure: Purity impacts toxicity, laboratory grade may slightly differ from industrial usage
First Aid Measures
General Advice: Remove contaminated clothing and shoes immediately. Ensure medical attention is obtained.
Inhalation: Move person to fresh air. Seek immediate medical advice. Monitor for respiratory distress, provide oxygen if breathing is difficult.
Skin Contact: Wash affected area with soap and large amounts of water for at least 15 minutes. Remove counterfeit or contaminated clothing.
Eye Contact: Rinse eyes cautiously with water for several minutes. Remove contact lenses if present. Continue rinsing.
Ingestion: Rinse mouth thoroughly, do not induce vomiting. Seek medical attention without delay.
Symptoms: Headache, dizziness, nausea, shortness of breath, pallor, impaired coordination. In severe cases, loss of consciousness or death.
Special Attention: Rescuers should have proper PPE. Advise emergency responders of nature of exposure.
Fire-Fighting Measures
Suitable Extinguishing Media: Alcohol-resistant foam, dry chemical powder, carbon dioxide (CO2). Avoid streams of water which may spread the fire.
Unsuitable Media: Direct water jets, due to risk of spreading flammable liquid.
Special Hazards: Vapor forms explosive mixture with air; containers may rupture in fire or when heated.
Hazardous Combustion Products: Hydrogen cyanide, nitrogen oxides, carbon monoxide, irritating and toxic fumes.
Protective Equipment: Firefighters require self-contained breathing apparatus, full protective gear.
Other Precautions: Evacuate area. Cool closed containers with water spray to prevent pressure build-up and possible explosion.
Accidental Release Measures
Personal Precautions: Avoid contact with skin, eyes, and clothing. Ensure adequate ventilation. Eliminate ignition sources. Use spark-proof tools.
Protective Equipment: Chemical-resistant gloves, goggles, face shield, appropriate respirator.
Environmental Precautions: Prevent spillage from entering drains, sewers, or waterways. Inform proper authorities if contamination occurs.
Spill Clean-Up: Contain and collect liquid with non-combustible absorbent materials (sand, earth, vermiculite). Place in proper labeled containers for disposal.
Decontamination: Clean affected area with water and detergent, ventilate area.
Handling and Storage
Handling Precautions: Work in well-ventilated area, preferably chemical fume hood. Do not breathe vapors or mist. Avoid all unnecessary exposure.
Storage Requirements: Store in tightly closed containers in cool, dry, well-ventilated area away from heat and ignition sources.
Incompatible Materials: Oxidizing agents, acids, chlorinated compounds, strong bases.
Bulk Storage: Use bonded bulk storage tanks with explosion-proof fittings.
Other Storage Notes: Segregate from food and drinking water. Protect from physical damage.
Exposure Controls and Personal Protection
Exposure Limits: OSHA PEL: 40 ppm TWA (ACGIH TLV: 20 ppm TWA)
Engineering Controls: Use with adequate local exhaust ventilation and explosion-proof electrical installations.
Personal Protective Equipment: Impermeable gloves (nitrile or butyl rubber), lab coat or appropriate chemical-resistant clothing, safety goggles, face shield.
Respiratory Protection: NIOSH-approved respirator in cases of insufficient ventilation or exposure above limits.
Hygiene Measures: Wash hands after handling, remove contaminated clothing, shower at end of shift.
Physical and Chemical Properties
Physical State: Colorless liquid
Odor: Ether-like, slightly sweet
Odor Threshold: 84 ppm
pH: Neutral (does not dissociate in water)
Boiling Point: 81.6°C (179°F)
Melting Point: -45°C (-49°F)
Flash Point: 2°C (closed cup)
Evaporation Rate: 5.79 (butyl acetate = 1)
Flammability: Highly flammable
Explosive Limits: Lower: 4.4%, Upper: 16% (in air)
Vapor Pressure: 88 mmHg (at 20°C)
Vapor Density: 1.4 (air = 1)
Density/Specific Gravity: 0.786 g/mL (at 20°C)
Solubility: Miscible with water, ethanol, ether
Partition Coefficient (log Kow): -0.34
Auto-ignition Temperature: 524°C (975°F)
Decomposition Products: Toxic fumes under fire conditions.
Stability and Reactivity
Chemical Stability: Stable at normal temperature and pressure when stored in original, unopened container.
Reactivity: Reacts violently with strong oxidizers, acids, alkali metals.
Conditions to Avoid: Heat, open flame, sparks, sources of ignition, incompatibles.
Hazardous Decomposition: Produces toxic vapors of hydrogen cyanide, carbon monoxide, nitrogen oxides.
Polymerization: Does not undergo hazardous polymerization.
Incompatible Materials: Strong oxidizing agents, acids, bases, chlorinated materials.
Toxicological Information
Acute Toxicity: Oral LD50 (rat): 2730 mg/kg. Dermal LD50 (rabbit): 1250 mg/kg. Inhalation LC50 (rat): 7551 ppm/8hr.
Chronic Toxicity: Prolonged exposure leads to liver, kidney, and central nervous system damage.
Routes of Exposure: Inhalation, ingestion, skin and eye contact.
Symptoms: Eye and respiratory tract irritation, dizziness, nausea, impaired coordination. High doses: unconsciousness, death due to respiratory failure or metabolic acidosis.
Carcinogenicity: Not listed as a human carcinogen by NTP, IARC, OSHA.
Mutagenicity: No confirmed mutagenic effects. Some animal studies show DNA damage at very high, non-occupational doses.
Reproductive Effects: Animal studies show problems at toxic dose ranges.
Ecological Information
Aquatic Toxicity: Acute: Fish LC50 (96 hr): 160 mg/L (fathead minnow)
Persistence and Degradability: Readily biodegradable in water, but volatile; may contribute to air pollution locally.
Bioaccumulation Potential: Low (log Kow < 1)
Mobility in Soil: High
Other Adverse Effects: Volatile, can contaminate air. Dangerous to aquatic invertebrates at high concentrations. Can contribute to cyanide formation in the environment if degraded incompletely.
Disposal in Water: May kill microorganisms in municipal water treatment at excessive concentration.
Environmental Exposure Controls: Do not release into environment uncontrolled.
Disposal Considerations
Waste Treatment Methods: Must be disposed in compliance with local, regional, and national regulations.
Disposal Containers: Use clearly labeled, sealed, chemical-resistant containers.
Recommended Disposal: Incinerate in chemical incinerator with afterburner and scrubber. Do not pour down drain or mix with household garbage.
Precautions for Disposal: Wear proper PPE, avoid inhalation of fumes.
Contaminated Packaging: Dispose per hazardous waste guidelines; triple rinse containers, remove all labeling before reuse or disposal.
Waste Code: EPA U009 (US); classification may vary by region.
Transport Information
UN Number: 1648
Proper Shipping Name: Acetonitrile
Hazard Class: 3 (Flammable Liquid)
Packing Group: II
Label Required: Flammable Liquid
Shipping Instructions: Keep away from heat and open flames. Only ship in approved containers with proper seals.
Special Precautions: Ensure emergency response information accompanies shipment.
Environmental Hazard: Classified as marine pollutant under some jurisdictions.
Other Info: Air transport ICAO/IATA: Forbidden on passenger aircraft, cargo only; Sea transport IMDG: Proper documentation and labeling mandatory.
Regulatory Information
OSHA Classification: Hazardous chemical
TSCA Status: Listed on US Toxic Substances Control Act Inventory
SARA Title III (Sections 302/311/312/313): Immediate (acute) and delayed (chronic) health hazard. Subject to reporting.
WHMIS (Canada): Class B2 (Flammable Liquid), Class D1B (Toxic Material)
REACH Status (EU): Registered; subject to restrictions on workplace handling
California Proposition 65: Not listed as cancer or reproductive toxicant
International Regulations: Listed on EINECS (European Union Inventory of Existing Commercial Chemical Substances). Australia's AICS, Japan ENCS, Korea, Philippines, China IECSC, New Zealand NZIoC
Other Compliance: Maintain records as required by local authorities for use and storage levels.
