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CHEMINFO Record Number: 593
CCOHS Chemical Name: n-Undecanoic acid

1-Decanecarboxylic acid
Hendecanoic acid
Undecanoic acid
n-Undecoic acid
n-Undecylic acid
Undecylic acid
Acide undécanoïque
Acide undécylique

CAS Registry Number: 112-37-8
RTECS Number(s): YQ2275000
EU EINECS/ELINCS Number: 203-964-2
Chemical Family: Aliphatic carboxylic acid / saturated aliphatic monocarboxylic acid / alkanoic acid / undecanoic acid
Molecular Formula: C11-H22-O2
Structural Formula: CH3-CH2-(CH2)7-CH2-C(=O)-OH


Appearance and Odour:
White crystalline solid or powder.(3)

Odour Threshold:
Not available. Can probably be detected at very low concentrations.

Warning Properties:
Insufficient information for evaluation.

Uses and Occurrences:
Used in organic synthesis.(2) Small amounts occur naturally in castor oil.(4)


White crystalline solid or powder. Can burn if strongly heated. POTENTIAL COMBUSTIBLE DUST HAZARD. Powdered material may form explosive dust-air mixtures. Causes eye irritation.


Effects of Short-Term (Acute) Exposure

Dusts and mists can probably cause mild irritation of the nose and throat. High concentrations can probably cause cough, sneezing and difficult breathing. There is no animal or human information available for n-undecanoic acid.

Skin Contact:
Dusts are probably non-irritating to mildly irritating. No irritation was observed following application of a 1 molar solution of undecanoic acid in propanol for 24 hours to the skin of 10 volunteers, using a patch which prevented evaporation from the skin.(1)

Eye Contact:
The dust can probably cause moderate to severe eye irritation, based on comparison to a related acid (dodecanoic acid). Some tearing, blinking and pain may occur as the solid material is rinsed from the eye from tears. There is no specific animal or human information available.

n-Undecanoic acid is used as a food additive, in very low concentrations.(2) It is probably low in oral toxicity, based on information for related aliphatic carboxylic acids. There is no specific human or animal information. Ingestion is not a typical route of occupational exposure.

Effects of Long-Term (Chronic) Exposure

SKIN CONTACT: Repeated or prolonged skin contact with dusts or solutions can cause irritation of the skin. Twenty-four hour daily application of a 1 M solution of undecanoic acid in propanol for 4 days resulted in redness in 8/10 volunteers, while application for 5 days produced redness in all 10 volunteers.(1)


There is no human or animal information available.

The International Agency for Research on Cancer (IARC) has not evaluated the carcinogenicity of this chemical.

The American Conference of Governmental Industrial Hygienists (ACGIH) has no listing for this chemical.

The US National Toxicology Program (NTP) has not listed this chemical in its report on carcinogens.

Teratogenicity and Embryotoxicity:
There is no human or animal information available.

Reproductive Toxicity:
There is no human or animal information available.

There is no information available.

Toxicologically Synergistic Materials:
There is no information available.

Potential for Accumulation:
n-Undecanoic acid does not accumulate in the body. Like other odd-carbon number carboxylic acids, this acid is metabolized to ketone bodies and converted to glucose and glycogen (used by the body), and to carbon dioxide, which is exhaled. It is also reported to be metabolized to nonanedicarboxylic acid and sebacic acid.(2)


If symptoms are experienced, remove source of contamination or have victim move to fresh air. If symptoms persist, obtain medical advice immediately.

Skin Contact:
If irritation occurs, remove contaminated clothing, shoes and leather goods (e.g. watchbands, belts). Gently blot or brush away excess chemical quickly. Wash gently and thoroughly with water and non-abrasive soap for at least 5 minutes or until the chemical is removed. If irritation persists, obtain medical advice immediately. Completely decontaminate clothing, shoes and leather goods before re-use or discard.

Eye Contact:
Gently blot or brush away excess chemical quickly. Immediately flush the contaminated eye(s) with lukewarm, gently flowing water for 20 minutes, or until the chemical is removed, while holding the eyelid(s) open. Take care not to rinse contaminated water into the non-affected eye. If irritation persists, obtain medical attention immediately.

If irritation or discomfort occur, obtain medical advice.

First Aid Comments:
Provide general supportive measures (comfort, warmth, rest).
Consult a doctor and/or the nearest Poison Control Centre for all exposures except minor instances of inhalation or skin contact.
All first aid procedures should be periodically reviewed by a doctor familiar with the material and its conditions of use in the workplace.


Flash Point:
Greater than 110 deg C (230 deg F) (closed cup) (3)

Lower Flammable (Explosive) Limit (LFL/LEL):
Not applicable

Upper Flammable (Explosive) Limit (UFL/UEL):
Not applicable

Autoignition (Ignition) Temperature:
Not available

Sensitivity to Mechanical Impact:
Stable material. Probably not sensitive.

Combustion and Thermal Decomposition Products:
Incomplete combustion may also produce irritating fumes and acrid smoke.

Flammable Properties:

Specific Hazards Arising from the Chemical:
During a fire, irritating/toxic gases and fumes may be generated.

Extinguishing Media:
Dry chemical powder, carbon dioxide, polymer foam, alcohol foam, water spray or fog.(3)

Fire Fighting Instructions:
Evacuate area and fight fire from a safe distance or a protected location. Approach fire from upwind to avoid toxic decomposition products.
Water or foam may cause frothing. The frothing may be violent and could endanger personnel close to the fire. However, a water spray or fog that is carefully applied to the surface of the burning material, preferably with a fine spray or fog nozzle, will cause frothing that will blanket and extinguish the fire. In addition, water spray or fog can be used to prevent dust formation, absorb heat, keep containers cool and protect exposed material. If a leak or spill has not ignited, use water spray to disperse the vapours and protect personnel attempting to stop a leak. Water spray may be used to flush spills away from ignition sources. Solid streams of water may be ineffective and spread material.
Its decomposition products may be hazardous to health. Do not enter without wearing specialized protective equipment suitable for the situation. Firefighter's normal protective equipment (Bunker Gear) will not provide adequate protection. Chemical resistant clothing (e.g. chemical splash suit and positive pressure self-contained breathing apparatus (MSHA/NIOSH approved or equivalent) may be necessary.


NFPA - Comments:
NFPA has no listing for this chemical in Codes 49 or 325.


Molecular Weight: 186.30

Conversion Factor:
Not applicable

Physical State: Solid
Melting Point: 29-30 deg C (84.2-86 deg F) (2,8)
Boiling Point: 284-284.6 deg C (543-544.3 deg F) (3,8,9)
Relative Density (Specific Gravity): 0.891 at 30 deg C (water = 1) (2,4)
Solubility in Water: Practically insoluble (9.3 mg/100 g at 20 deg C) (9)
Solubility in Other Liquids: Very soluble in acetone, benzene and cyclohexane; soluble in ethanol and diethyl ether (2,9)
Coefficient of Oil/Water Distribution (Partition Coefficient): Log P(oct) = 1.06 (4)
pH Value: Not applicable (practically insoluble in water)
Vapour Density: Not applicable
Vapour Pressure: Extremely low at room temperature; 0.133 kPa (1 mm Hg) at 101.4 deg C (2,10)
Saturation Vapour Concentration: Extremely low at room temperature
Evaporation Rate: Not available
Critical Temperature: Not available

Other Physical Properties:
ACIDITY: Weak acid
VISCOSITY-DYNAMIC: 7.3 mPa.s (7.3 centipoise) at 50 deg C (9)
VISCOSITY-KINEMATIC: Approximately 8.33 mm2/m (8.33 centistokes) at 50 deg C (calculated)


Normally stable at ambient temperatures. Exposure to light or air may cause a very slow breakdown, producing a rancid odour (due to short chain (C1- C10) aldehyde and ketone formation) and low levels of peroxides, which are not likely to be hazardous.(11,12)

Hazardous Polymerization:
Does not occur

Incompatibility - Materials to Avoid:

NOTE: Chemical reactions that could result in a hazardous situation (e.g. generation of flammable or toxic chemicals, fire or detonation) are listed here. Many of these reactions can be done safely if specific control measures (e.g. cooling of the reaction) are in place. Although not intended to be complete, an overview of important reactions involving common chemicals is provided to assist in the development of safe work practices.

OXIDIZING AGENTS (e.g. chromium trioxide, nitric acid, peroxides, permanganates) - may react violently or explosively. Increased risk of fire.(3)
BASES (including alkalis, such as sodium hydroxide) - vigorous or violent reaction may occur, yielding heat and pressure.(3)
REDUCING AGENTS (e.g. hydrides such as lithium aluminum hydride) - reaction may be vigorous or violent.(3)

Hazardous Decomposition Products:
Peroxides, aldehydes and ketones may form during the slow breakdown of n-undecanoic acid in the presence of air or light.(11)

Conditions to Avoid:
Temperatures above 110 deg C, open flames, generation of dust

Corrosivity to Metals:
Specific information is not available. The related acid, n-decanoic acid, is not corrosive to cast iron, steel, stainless steel, including types 304 and 316, aluminum, copper, bronze, brass, nickel and its alloys at room temperature. Steel and 304 stainless steels, to a small extent, may be corroded at very high temperatures, while aluminum may be attacked at elevated temperatures. High acid concentrations may severely corrode 304 stainless steels.(13,14)


There is no specific animal toxicity information available.


Selected Bibliography:
(1) Stillman, M.A., et al. Relative irritancy of free fatty acids of different chain length. Contact Dermatitis. Vol. 1, no. 2 (1975). p. 65-69
(2) Katz, G.V., et al. Aliphatic carboxylic acids. In: Patty's industrial hygiene and toxicology. 4th edition. Edited by G.D. Clayton et al. Volume II. Toxicology. Part E. John Wiley and Sons, 1994. p. 3523-3527, 3530, 3561-3562
(3) The Sigma-Aldrich library of chemical safety data. Edition II. Volume 2. Sigma-Aldrich Corporation, 1988. p. 3572C
(4) Verschueren, K. Handbook of environmental data on organic chemicals. 3rd edition. Van Nostrand Reinhold, 1996. p. 1874
(5) Grossel, S.S. Safety considerations in conveying of bulk solids and powders. Journal of Loss Prevention in the Process Industries. Vol. 1 (April, 1988). p. 62-74
(6) Fire protection handbook. 17th edition. National Fire Protection Association, 1991. p. 2-332 to 2-333, 3-133 to 3-142
(7) Forsberg, K., et al. Quick selection guide to chemical protective clothing. 3rd edition. Van Nostrand Reinhold, 1997
(8) Riemenschneider, W. Carboxylic acid, aliphatic. In: Ullmann's encyclopedia of industrial chemistry. 5th completely revised edition. Volume A 5. VCH Verlagsgesellschaft, 1985. p. 235-246
(9) Bagby, M.O. Carboxylic acids: survey. In: Kirk-Othmer encyclopedia of chemical technology. 4th edition. Volume 5. John Wiley and Sons, 1993. p. 147-168
(10) Weast, R.C., ed. Handbook of chemistry and physics. 66th edition. CRC Press, 1985-1986. p. C-537, D-208
(11) Brockmann, R., et al. Fatty acids. In: Ullmann's encyclopedia of industrial chemistry. 5th completely revised edition. Volume A 10. VCH Verlagsgesellschaft, 1985. p. 245-276
(12) Perkins, E.G. Carboxylic acids: analysis and standards of fatty acids. In: Kirk-Othmer encyclopedia of chemical technology. 3rd edition. Volume 4. John Wiley and Sons, 1978. p. 845-853
(13) Corrosion data survey: metals section. 6th edition. National Association of Corrosion Engineers, 1985. p. 32-2 to 33-2
(14) Elder, G.B. Corrosion by organic acid. In: Process industries corrosion. National Association of Corrosion Engineers, 1975. p. 247-254
(15) Phillips, L., et al. A comparison of rabbit and human skin response to certain irritants. Toxicology and Applied Pharmacology. Vol. 21, no. 3 (Mar. 1972). p. 369-382

Information on chemicals reviewed in the CHEMINFO database is drawn from a number of publicly available sources. A list of general references used to compile CHEMINFO records is available in the database Help.

Review/Preparation Date: 1997-08-25

Revision Indicators:
Resistance of materials 1998-04-01
Skin protection 1998-04-01
Bibliography 2006-04-13
Emergency overview 2006-10-05

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