Acetonitrile

1Identification

Name

Acetonitrile

IUPAC name

acetonitrile

CAS number

75-05-8

EC number

200-835-2

Molecular formula

C2H3N

Molecular weight

41.05 g/mol

InChIKey

WEVYAHXRMPXWCK-UHFFFAOYSA-N

SMILES

CC#N

PubChem CID

6342

Synonyms

Methyl cyanide, Cyanomethane, Ethanenitrile, Ethyl nitrile, Methane, cyano-, Methanecarbonitrile, Acetonitril, Cyanure de methyl, Methylkyanid, USAF EK-488, MeCN, RefChem:6609, Methylkyanid [Czech], Cyanure de methyl [French]

Recommended uses

• Acetonitrile is predominantly used as a solvent in the manufacture of pharmaceuticals, for spinning fibers and for casting and molding of plastic materials, in lithium batteries, for the extraction of fatty acids from animal and vegetable oils, and in chemical laboratories for the detection of materials such as pesticide residues.
  EPA Hazardous Air Pollutants
• Used as a solvent for extraction of hydrocarbons, for separation of fatty acids from vegetable oils, and as a specialty solvent; [ACGIH]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Semiconductor Manufacturing [Category: Industry]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Fuel Processing aids not otherwise specified Other Solvent Laboratory chemicals Dye Intermediate Not Known or Reasonably Ascertainable Cleaning agent
  EPA Chemical Data Reporting (CDR)
• Not Known or Reasonably Ascertainable Laboratory chemicals Intermediate Solvent
  EPA Chemical Data Reporting (CDR)

Description

• Acetonitrile appears as a colorless limpid liquid with an aromatic odor. Flash point 42 °F. Density 0.783 g / cm3. Toxic by skin absorption. Less dense than water. Vapors are denser than air.
  CAMEO Chemicals
• Acetonitrile is a nitrile that is hydrogen cyanide in which the hydrogen has been replaced by a methyl group. It has a role as a polar aprotic solvent and an EC 3.5.1.4 (amidase) inhibitor. It is a volatile organic compound and an aliphatic nitrile.
  ChEBI
• Acetonitrile has many uses, including as a solvent, for spinning fibers, and in lithium batteries. It is primarily found in air from automobile exhaust and manufacturing facilities. Acute (short-term) inhalation exposure results in irritation of mucous membranes. Chronic (long-term) exposure results in central nervous system effects, such as headaches, numbness, and tremors. No data are available on its carcinogenic effects in humans; EPA has classified it as a Group D, not classifiable as to human carcinogenicity.
  EPA Hazardous Air Pollutants

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

• 2 - Materials that, under emergency conditions, can cause temporary incapacitation or residual injury.
  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

• Exposure to 160 ppm for 4 hours causes flushing of the face and a feeling of constriction in the chest; 500 ppm for brief periods is irritating to the nose and throat. Severe exposures cause irritability, skin eruptions, confusion, delirium, convulsions, paralysis, and death due to central nervous system depression. (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

• Special Hazards of Combustion Products: Toxic vapors are generated when heated Behavior in Fire: Vapor heavier than air and may travel a considerable distance to a source of ignition and flash back. (USCG, 1999)
  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. Gives off irritating or toxic fumes (or gases) in a fire. Vapour/air mixtures are explosive. Risk of fire and explosion on contact with strong oxidants. Heating will cause rise in pressure with risk of bursting.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Hazards summary

• Acetonitrile has many uses, including as a solvent, for spinning fibers, and in lithium batteries. It is primarily found in air from automobile exhaust and manufacturing facilities. Acute (short-term) inhalation exposure results in irritation of mucous membranes. Chronic (long-term) exposure results in central nervous system effects, such as headaches, numbness, and tremors. No data are available on its carcinogenic effects in humans; EPA has classified it as a Group D, not classifiable as to human carcinogenicity.
  EPA Hazardous Air Pollutants
• In subchronic animal studies, histopathological liver effects occur. In a human inhalation study, all five subjects detected the odor at 40 ppm, the initial concentration of the experiment. After two or three hours, some olfactory fatigue was observed. A fatality was reported in a worker who painted for 2 days in a confined space with a resin containing 30-40% acetonitrile. [ACGIH] Cases have been reported of children developing symptoms of cyanide poisoning within hours of drinking acetonitrile-based artificial nail remover. [ATSDR Case Studies # 15] In reproductive studies of experimental animals, acetonitrile causes fetal skeletal abnormalities. [Frazier, p. 349-50] See NITRILES.
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

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 flush immediately - If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly. Breathing: Respiratory support 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

• Sore throat. Weakness. Chest tightness. Shortness of breath. Dizziness. Nausea. Vomiting. Convulsions. Unconsciousness. Symptoms may be delayed.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• EASILY ABSORBED!
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness. Pain.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• Foam, carbon dioxide, dry chemical
  Hazardous Substances Data Bank (HSDB)
• Stay upwind and use water spray to knock down vapor.
  Hazardous Substances Data Bank (HSDB)
• Approach fire from upwind to avoid hazardous vapors and toxic decomposition products. Use water spray, dry chemical, "alcohol resistant" foam, or carbon dioxide. Use water spray to keep fire-exposed containers cool.
  Hazardous Substances Data Bank (HSDB)

Hazardous combustion products

• Poisonous gases including hydrogen cyanide and nitrogen oxides are produced in fire.
  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

• Consult an expert! Personal protection: complete protective clothing including self-contained breathing apparatus. Ventilation. Remove all ignition sources. Collect leaking and spilled liquid in sealable containers as far as possible. Absorb remaining liquid in dry sand or inert absorbent. Then store and dispose of according to local regulations.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• ACCIDENTAL RELEASE MEASURES. Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid breathing vapours, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Beware of vapours accumulating to form explosive concentrations. Vapours can accumulate in low areas.; Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains.;
  Hazardous Substances Data Bank (HSDB)
• 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. Use foam spray to reduce vapors. Absorb liquids in vermiculite, dry sand, earth, or a similar material and deposit in sealed containers. Keep acetonitrile out of a confined space, such as a sewer, because of the potential for an explosion, unless the sewer is designed to prevent the build-up of explosive concetrations. It may be necessary to contain and dispose of this chemical as a hazardous waste.
  Hazardous Substances Data Bank (HSDB)
• 1) Remove all ignition sources. 2) Ventilate area of spill or leak. 3) For small quantities, absorb on paper towels. Evaporate in safe place (such as fume hood). Allow ... vapors to completely clear ductwork. Burn paper in suitable location away from combustible materials. Large quantities can be collected & atomized in suitable combustion chamber equipped with appropriate effluent gas cleaning device. ... /It/ should not be allowed to enter confined space, such as sewer ...
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Fireproof. Keep in a well-ventilated room. Separated from acids, bases, strong oxidants and food and feedstuffs. Well closed.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Protect containers against physical damage. Outdoor or detached storage is preferable. Separate from any sources of ignition and combustible materials. Storage room should be well-ventilated.
  Hazardous Substances Data Bank (HSDB)
• Inside storage should be in a standard flammable liquids storage warehouse, room, or cabinet. Separate from oxidizing materials. Outside or detached storage is preferred.
  Hazardous Substances Data Bank (HSDB)
• Store in tightly closed containers in a cool, well ventialted area. Metal containers involving the transfer of this chemical should be grounded and bonded. Where possible, automatically pump liquid from drums or other storage containers to process containers. Drums must be equipped with self-closing valves, pressure vacuum bungs; and flame arresters. Use only non-sparking tools and equipment, especially when opening and closing containers of this chemical.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

Personal protective equipment

• Excerpt from NIOSH Pocket Guide for Acetonitrile: 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
• NIOSH: 200 ppm: CcrOV (APF = 10) [any air-purifying half-mask respirator equipped with an organic vapor cartridge(s)]; Sa APF = 10) (any supplied-air respirator); or SCBA (any self-contained breathing apparatus); 500 ppm: Sa:Cf (APF = 25) (any supplied-air respirator operated in a continous-flow mode); or PaprOv (APF = 25) [any powered, air-purifying respirator with organic vapor cartridge(s)]; or CcrFOv (APF = 50) [any powered, air- purifying respirator with organic vapor cartridge(s)]; or CcrFOv (APF = 50) [any chemical cartridge respirator with a full face-piece and organic vapor cartridge(s)];
  Hazardous Substances Data Bank (HSDB)
• Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.
  Hazardous Substances Data Bank (HSDB)
• Wear appropriate personal protective clothing to prevent skin contact.
  Hazardous Substances Data Bank (HSDB)

Respirator recommendations

• NIOSH Up to 200 ppm: (APF = 10) Any chemical cartridge respirator with organic vapor cartridge(s) (APF = 10) Any supplied-air respirator Up to 500 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 int…
  The National Institute for Occupational Safety and Health (NIOSH)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• ACETONITRILE decomposes when heated to produce deadly toxic hydrogen cyanide gas and oxides of nitrogen. Strongly reactive [Hawley]. May react vigorously with strong oxidizing reagents, sulfuric acid, chlorosulfonic acid, sulfur trioxide, perchlorates, nitrating reagents, and nitric acid. [Sax, 9th ed., 1996, p. 20]. Potentially explosive in contact with nitrogen-fluorine compounds (e.g., tetrafluorourea) [Fraser, G. W. et al., Chem. Comm., 1966, p. 532].
  CAMEO Chemicals
• Highly flammable. Water soluble.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Strong oxidizers such as chlorine, bromine, and fluorine; chlorosulfonic acid; oleum or sulfuric acid. May accumulate static electricial charges, and may cause ignition of its vapors.
  Hazardous Substances Data Bank (HSDB)
• Strong oxidizers.
  Hazardous Substances Data Bank (HSDB)
• Will react with water, steam, acids to produce toxic & flammable vapors.
  Hazardous Substances Data Bank (HSDB)

Chemical stability

• Heat /contributes to instability/.
  Hazardous Substances Data Bank (HSDB)

11Toxicological information

Target organs

• respiratory system, cardiovascular system, central nervous system, liver, kidneys
  The National Institute for Occupational Safety and Health (NIOSH)

Short-term exposure effects

• The substance is irritating to the eyes. The substance may cause effects on the cellular respiration (inhibition). This may result in convulsions and respiratory failure. Exposure far above the OEL could cause death. The effects may be delayed. Medical observation is indicated.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Long-term exposure effects

• The substance may have effects on the blood. This may result in anaemia. The substance may have effects on the kidneys, liver and thyroid. This may result in impaired functions.
  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 number U003, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.
  Hazardous Substances Data Bank (HSDB)
• SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal.
  Hazardous Substances Data Bank (HSDB)
• Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (>/= 100 kg/mo) must conform with EPA regulations governing storage, transportation, treatment, and waste disposal. Incineration with nitrogen oxide removal from effluent gases by scrubbers or incinerators.
  Hazardous Substances Data Bank (HSDB)

14Transport information

UN number: UN 1648

Shipping name

• UN 1648; Acetonitrile
  Hazardous Substances Data Bank (HSDB)
• IMO 3; Acetonitrile
  Hazardous Substances Data Bank (HSDB)

DOT hazard class

• Acetonitrile
  US Code of Federal Regulations, Hazardous Materials, 49 CFR Part 172
• UN1648
  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

• 1648 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. Acetonitrile is produced, as an intermediate or a final product, by process units covered under this subpart.
  Hazardous Substances Data Bank (HSDB)
• Toxic pollutant designated pursuant to section 307(a)(1) of the Federal Water Pollution Control Act and is subject to effluent limitations. /Cyanides/
  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. Acetonitrile is included on this list. Effective date: 10/4/82; Sunset date: 10/4/92.
  Hazardous Substances Data Bank (HSDB)
• U003; As stipulated in 40 CFR 261.33, when acetonitrile, 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)

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

16Other information

Compiled from PubChem CID 6342 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.