Isoamyl Alcohol

1Identification

Name

Isoamyl Alcohol

IUPAC name

3-methylbutan-1-ol

CAS number

123-51-3 (also reported: 6423-06-9, 50858-14-5)

EC number

204-633-5

Molecular formula

C5H12O

Molecular weight

88.15 g/mol

InChIKey

PHTQWCKDNZKARW-UHFFFAOYSA-N

SMILES

CC(C)CCO

PubChem CID

31260

Synonyms

Isoamyl alcohol, 3-Methyl-1-butanol, Isopentyl alcohol, 3-Methylbutan-1-ol, Isopentanol, 3-Methylbutanol, 1-Butanol, 3-methyl-, Isoamylol, Isobutylcarbinol, 2-Methyl-4-butanol, Isobutyl carbinol, Iso-amylalkohol, Alcool isoamylique, Amylowy alkohol

Recommended uses

• Used as a solvent, paint stripper, and intermediate in the photographic and pharmaceutical industries; [ACGIH]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• Painting (Solvents) [Category: Paint] Photographic Processing [Category: Other]
  Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
• SYNTHETIC FLAVOR; INTERMEDIATE IN PREPN OF PHARMACEUTICALS; FOR ISOAMYL ACETATE AND OTHER ESTERS; FOR DITHIOPHOSPHATE ESTERS (LUBRICATING OIL ADDITIVE AND HYDRAULIC FLUID ADDITIVE)
  Hazardous Substances Data Bank (HSDB)
• Solvent Flotation agent
  EPA Chemical Data Reporting (CDR)

Use categories: Fragrance Ingredients · Flavouring Agent -> FLAVOURING_AGENT -> JECFA Functional Classes · Flavoring Agents -> JECFA Flavorings Index · Cosmetics -> Solvent

Description

• Isoamyl alcohol is a colorless liquid with a mild, choking alcohol odor. Less dense than water, soluble in water. Hence floats on water. Produces an irritating vapor. (USCG, 1999)
  CAMEO Chemicals
• Isoamylol is an primary alcohol that is butan-1-ol in which a hydrogen at position 3 has been replaced by a methyl group. It has a role as an antifungal agent, a Saccharomyces cerevisiae metabolite and a xenobiotic metabolite. It is a volatile organic compound, a primary alcohol and an alkyl alcohol. It derives from a hydride of an isopentane.
  ChEBI
• isoamyl alcohol has been reported in Ambrosiozyma monospora, Humulus lupulus, and other organisms with data available.
  LOTUS - the natural products occurrence database

2Hazard identification

Signal word

Danger

Pictograms

GHS02, GHS05, GHS07

Classification source

European Chemicals Agency (ECHA)

Precautionary statements

Other reported classifications

4 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)
• 2 - Materials that must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur. Materials would not under normal conditions form hazardous atmospheres with air, but under high ambient temperatures or under moderate heating could release vapor in sufficient quantities to produce hazardous atmospheres with air.
  Hazardous Substances Data Bank (HSDB)
• 0 - Materials that in themselves are normally stable, even under fire conditions.
  Hazardous Substances Data Bank (HSDB)

Health hazards

• Very high vapor concentrations irritate eyes and upper respiratory tract. Continued contact with skin may cause irritation. (USCG, 1999)
  CAMEO Chemicals

Fire hazards

• Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]: HIGHLY FLAMMABLE: Will be easily ignited by heat, sparks or flames. 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. Containers may explode when heated. Many liquids will float on water. (ERG, 2024)
  CAMEO Chemicals
• Flammable. Above 42 °C explosive vapour/air mixtures may be formed.
  ILO-WHO International Chemical Safety Cards (ICSCs)

Hazards summary

• Rabbits become stuporous after an oral dose of 0.7 g/kg. [ACGIH] A skin, eye, and respiratory tract irritant; May have effects on the CNS if ingested; [ICSC]
  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

• Excerpt from NIOSH Pocket Guide for Isoamyl alcohol (primary): 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 PROMPTLY - If this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water promptly. If irritation persists after washing, get medical attention. Breathing: RESPIRATORY SUPPORT - If a person breathes large amounts of this chemical, move the exposed person to fresh air at once.
  CAMEO Chemicals
• (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 promptly - If this chemical contacts the skin, flush the contaminated skin with water promptly. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water promptly. If irritation persists after washing, get medical attention. 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. Cough. Burning sensation.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Dry skin. Redness.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• Redness. Pain.
  ILO-WHO International Chemical Safety Cards (ICSCs)

5Fire-fighting measures

• Use water, powder, "alcohol" foam or carbon tetrachloride. Water spray is effective for cooling fire-exposed containers, dispersing spills before burning, and protection from heat those persons engaged to stop leakage during the fire.
  Hazardous Substances Data Bank (HSDB)
• If material on fire or involved in fire: Do not extinguish fire unless flow can be stopped. 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, carbon dioxide or dry chemical.
  Hazardous Substances Data Bank (HSDB)

Hazardous combustion products

• Toxic gases and vapors (such as carbon monoxide) may be released in a fire involving isoamyl alcohol.
  Hazardous Substances Data Bank (HSDB)

6Accidental release measures

Isolation and evacuation

• Excerpt from ERG Guide 129 [Flammable Liquids (Water-Miscible / Noxious)]: 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

Spill cleanup

• Personal protection: protective clothing, safety goggles and filter respirator for organic gases and vapours adapted to the airborne concentration of the substance. Collect leaking and spilled liquid in sealable non-plastic containers as far as possible. Absorb liquid in sand or inert absorbent. Wash away remainder with plenty of water.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• 1. Remove all ignition sources. 2. Ventilate area of spill or leak. 3. For small quantities, absorb on paper towels. Evaporate in a safe place (such as a fume hood). Allow sufficient time for evaporating vapors to completely clear the hood ductwork. Burn the paper in a suitable location away from combustible materials. ... Isoamyl alcohol should not be allowed to enter a confined space, such as a sewer, because of the possibility of an explosion.
  Hazardous Substances Data Bank (HSDB)

7Handling and storage

• Fireproof. Separated from strong oxidants and reducing agents.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• IN GENERAL, MATERIALS WHICH ARE TOXIC AS STORED OR WHICH CAN DECOMP INTO TOXIC COMPONENTS ... SHOULD BE STORED IN A COOL, WELL-VENTILATED PLACE, OUT OF DIRECT RAYS OF THE SUN, AWAY FROM AREAS OF HIGH FIRE HAZARD, & SHOULD BE PERIODICALLY INSPECTED ... INCOMPATIBLE MATERIALS SHOULD BE ISOLATED FROM EACH OTHER.
  Hazardous Substances Data Bank (HSDB)
• Remove source of ignition. Keep containers closed. Store in prescribed, controllable places.
  Hazardous Substances Data Bank (HSDB)

8Exposure controls / personal protection

Personal protective equipment

• Excerpt from NIOSH Pocket Guide for Isoamyl alcohol (primary): 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 OR CONTAMINATED - Work clothing that becomes wet or significantly contaminated should be removed and replaced. Change: No recommendation is made specifying the need for the worker to change clothing after the workshift. (NIOSH, 2024)
  CAMEO Chemicals
• Wear appropriate personal protective clothing to prevent skin contact.
  Hazardous Substances Data Bank (HSDB)
• Wear appropriate eye protection to prevent eye contact.
  Hazardous Substances Data Bank (HSDB)
• Recommendations for respirator selection. Max concn for use: 500 ppm. Respirator Class(es): Any supplied-air respirator operated in a continuous flow mode. Eye protection needed. Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s). Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister. Any powered, air-purifying respirator with organic vapor cartridge(s). Eye protection needed. Any self-contained breathing apparatus with a full facepiece. Any supplied-air respirator with a full facepiece.
  Hazardous Substances Data Bank (HSDB)

Respirator recommendations

• NIOSH/OSHA Up to 500 ppm: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode (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 = 25) Any powered, air-purifying respirator with organic vapor cartridge(s) (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 a…
  The National Institute for Occupational Safety and Health (NIOSH)

9Physical and chemical properties

10Stability and reactivity

Reactivity

• ISOAMYL ALCOHOL attacks plastics [Handling Chemicals Safely, 1980. p. 236]. Mixtures with concentrated sulfuric acid and strong hydrogen peroxide may cause explosions. Mixing with hypochlorous acid in water or water/carbon tetrachloride solution can generate isoamyl hypochlorites, which may explode, particularly on exposure to sunlight or heat. Mixing with chlorine would also yield isoamyl hypochlorites [NFPA 491 M, 1991]. Base-catalysed reactions with isocyanates can occur with explosive violence [Wischmeyer,1969].
  CAMEO Chemicals
• Highly flammable. Water soluble.
  CAMEO Chemicals

Incompatible materials and hazardous reactions

• Strong oxidizers.
  Hazardous Substances Data Bank (HSDB)
• Interaction /of pentanol and hydrogen trisulfide/ is explosively violent. /Pentanol/
  Hazardous Substances Data Bank (HSDB)
• Strong oxidizers
  The National Institute for Occupational Safety and Health (NIOSH)

11Toxicological information

Routes of exposure

• The substance can be absorbed into the body by inhalation and by ingestion.
  ILO-WHO International Chemical Safety Cards (ICSCs)
• inhalation, ingestion, skin and/or eye contact
  The National Institute for Occupational Safety and Health (NIOSH)

Target organs

• Eyes, skin, respiratory system, central nervous system
  The National Institute for Occupational Safety and Health (NIOSH)

Short-term exposure effects

• The substance is severely irritating to the eyes. The substance is irritating to the respiratory tract. The substance is mildly irritating to the skin. Ingestion could cause effects on the central nervous system. If swallowed the substance may cause vomiting 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.
  ILO-WHO International Chemical Safety Cards (ICSCs)

12Ecological information

Environmental fate

• Isopentanol is a naturally occurring substance that is released to the environment by plants, microorganisms, and from animal wastes. It may also be released during its manufacture, transport, disposal and use as a solvent, extracting agent, additive, photographic chemical, chemical intermediate in the production of herbicides and pharmaceuticals, in the synthesis of flavors and fragrances, and during the fermentation of sugars and starches. If released on soil, it should readily volatilize as well as leach. Based upon results from biodegradation studies with surface water and ground water, biodegradation in soil should be rapid. If released in water, it should also be lost by evaporation.
  Hazardous Substances Data Bank (HSDB)

13Disposal considerations

• SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.
  Hazardous Substances Data Bank (HSDB)
• Spray into the furnace. Incineration will become easier by mixing with a more flammable solvent.
  Hazardous Substances Data Bank (HSDB)
• 1. By absorbing it in vermiculite, dry sand, earth or a similar material and disposing in a secured sanitary landfill. 2. By atomizing in a suitable combustion chamber.
  Hazardous Substances Data Bank (HSDB)

14Transport information

UN number: UN 1105

Shipping name

• UN 1105; Isoamyl alcohol
  Hazardous Substances Data Bank (HSDB)
• IMO 3.3; Isoamyl alcohol
  Hazardous Substances Data Bank (HSDB)

DOT label

• Flammable Liquid
  CAMEO Chemicals

UN classification

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

Emergency Response Guidebook

• 1105 129
  The National Institute for Occupational Safety and Health (NIOSH)

How DOT hazard classes work →

15Regulatory information

• Isoamyl alcohol is a food additive permitted for direct addition to food for human consumption as a synthetic flavoring substance and adjuvant in accordance with the following conditions: 1) the quantity added to food does not exceed the amount reasonably required to accomplish its intended physical, nutritive, or other technical effect in food, and 2) when intended for use in or on food it is of appropriate food grade and is prepared and handled as a food ingredient.
  Hazardous Substances Data Bank (HSDB)

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

16Other information

Compiled from PubChem CID 31260 and the sources it aggregates (attributed inline). Data retrieved 2026-10-12. This summary describes the pure substance and is not a supplier SDS.