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CHEMINFO Record Number: 435
CCOHS Chemical Name: n-Undecane

Undécane normal

CAS Registry Number: 1120-21-4
UN/NA Number(s): 2330
RTECS Number(s): YQ1525000
EU EINECS/ELINCS Number: 214-300-6
Chemical Family: Saturated aliphatic hydrocarbon / alkane / n-alkane / undecane
Molecular Formula: C11-H24
Structural Formula: CH3-(CH2)9-CH3


Appearance and Odour:
Colourless liquid with a gasoline-like odour.

Odour Threshold:
3.6 ppm (23 mg/m3) (50% detection); 58.65 ppm (376 mg/m3) 50% (recognition) (2)

Warning Properties:
Insufficient information for evaluation

Uses and Occurrences:
Component of gasoline, jet fuel, kerosene, photocopying fluids and petroleum solvents such as white spirit; solvent; organic synthesis; petroleum research; and distillation chaser.


Colourless liquid, gasoline-like odour. COMBUSTIBLE LIQUID AND VAPOUR. Liquid can float on water and may travel long distances and/or spread fire. Liquid can accumulate static charge. May be irritating to eyes, skin and respiratory tract. Mild central nervous system depressant. Extremely high vapour concentrations may cause headache, nausea, dizziness and drowsiness. Aspiration hazard. Swallowing or vomiting of the liquid may result in aspiration into the lungs.


Effects of Short-Term (Acute) Exposure

Because of low vapour pressure and low saturated vapour concentration of decanes, it is unlikely to produce a sufficiently high vapour concentration to cause effects unless material is heated or mists are formed. In this case depression of the central nervous system may result in drowsiness, dizziness, confusion and incoordination. Based on skin irritation resulting from dermal exposure, concentrated vapour may cause nose and throat irritation.

Skin Contact:
Based on effects in animal studies, direct skin contact with decanes may cause moderate to severe irritation.

Eye Contact:
Eye contact will probably cause moderate to severe irritation with redness and pain. Concentrated vapour is probably irritating to the eyes. This evaluation is based on an animal skin irritancy study which produced moderate to severe skin irritation.

There is no specific information for n-undecane. Decanes in general have very low oral toxicity and large amounts would have to be ingested to cause depression of the central nervous system as described for inhalation above.
Based on physical properties, decanes can be easily aspirated into the lungs. Aspiration is the "breathing" of a material into the lungs when it is swallowed or vomited. This could result in potentially fatal lung damage (pulmonary edema).
Ingestion is not a typical route of occupational exposure.

Effects of Long-Term (Chronic) Exposure

No chronic effects in humans have been reported.
SKIN: Based on results from animal studies, irritation and dermatitis (inflammation, reddening and swelling) may result from prolonged or repeated contact.


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 human information available. Negative results have been obtained with mammalian cells in vitro. n-Undecane may act as a promoter of mutagenicity.

Toxicologically Synergistic Materials:
Information not available

Potential for Accumulation:
Unlikely to accumulate. Decanes are readily metabolized and excreted from the body.


Remove source of contamination or move victim to fresh air. If breathing has stopped, trained personnel should begin artificial respiration or, if the heart has stopped, cardiopulmonary resuscitation (CPR) immediately. Obtain medical attention immediately.

Skin Contact:
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 20 minutes or until the chemical is removed. If irritation persists, obtain medical attention immediately. Completely decontaminate clothing, shoes and leather goods before re-use, or discard.

Eye Contact:
Quickly and gently blot or brush away excess chemical. Immediately flush the contaminated eye(s) with lukewarm, gently flowing water for 5 minutes or until the chemical is removed, while holding the eyelid(s) open. Obtain medical advice immediately.

Never give anything by mouth if victim is rapidly losing consciousness, is unconscious or convulsing. DO NOT INDUCE VOMITING. Have victim drink 240 to 300 mL (8 to 10 oz.) of water. If vomiting occurs naturally, have victim lean forward to reduce risk of aspiration. Repeat administration of water. Obtain medical attention immediately.

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:
60 deg C (140 deg F) (closed cup) (5); 65 deg C (149 deg F) (open cup) (7)

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

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

Autoignition (Ignition) Temperature:
Not available

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

Sensitivity to Static Charge:
Specific information is not available. By comparison to other hydrocarbons, undecane may accumulate static charge by flow or agitation, since hydrocarbons have low electrical conductivities. Vapours from heated liquid, at concentrations in the flammable range, can be ignited by a static spark.

Fire Hazard Summary:
Combustible liquid. Vapour can form flammable or explosive mixtures with air at, or above 60 deg C. Liquid can float on the top of water and travel long distances and/or spread fire. During a fire, irritating/toxic gases may be generated. Vapours from heated liquid can accumulate in confined spaces, resulting in a flammability hazard. Closed containers may rupture violently when heated.

Extinguishing Media:
Carbon dioxide, dry chemical powder, alcohol foam or polymer foam, water spray or fog.(5) Water may be ineffective. (7)

Fire Fighting Instructions:
Evacuate area and fight fire from a safe distance or protected location. Approach fire from upwind to avoid hazardous vapours and toxic decomposition products.
Stop leak before attempting to stop the fire. If the leak cannot be stopped, and if there is no risk to the surrounding area, let the fire burn itself out. If a leak or spill has not ignited, use water spray in large quantities to disperse the vapours and to protect personnel attempting to stop a leak. Water spray can also be used to flush spills away from ignition sources. Solid streams of water may be ineffective and spread material.
Closed containers may explode in the heat of the fire. If possible, isolate materials not yet involved in the fire and move containers from fire area if this can be done without risk, and protect personnel. Otherwise, fire-exposed containers or tanks should be cooled by application of hose streams and this should begin as soon as possible and should concentrate on any unwetted portions of the container.
For a massive fire in a large area, use unmanned hose holder or monitor nozzles; if this is not possible withdraw from fire area and allow fire to burn. Stay away from ends of tanks. Withdraw immediately in case of rising sound from venting safety device or any discolouration of tank due to fire.
Firefighters may enter the area if positive pressure self-contained breathing apparatus (MSHA/NIOSH approved or equivalent) and full Bunker Gear is worn.


NFPA - Health: 1 - Exposure would cause significant irritation, but only minor residual injury.
NFPA - Flammability: 2 - Must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur.
NFPA - Instability: 0 - Normally stable, even under fire conditions, and not reactive with water.


Molecular Weight: 156.31

Conversion Factor:
1 ppm = 6.38 mg/m3; 1 mg/m3 = 0.157 ppm at 25 deg C (calc.)

Physical State: Liquid
Melting Point: -25.59 deg C (-14 deg F) (1)
Boiling Point: 196 deg C (385 deg F) (5)
Relative Density (Specific Gravity): 0.74 at 20 deg C (2,5); 0.744 at 25 deg C (water = 1)
Solubility in Water: Insoluble (1)
Solubility in Other Liquids: Soluble in most organic solvents (2)
Coefficient of Oil/Water Distribution (Partition Coefficient): Not available
pH Value: Not applicable
Vapour Density: 5.4 (air = 1) (5,7)
Vapour Pressure: 0.052 kPa (0.4 mm Hg) at 25 deg C (2)
Saturation Vapour Concentration: 520 ppm (0.052%) at 25 deg C (calc.)
Evaporation Rate: Not available
Critical Temperature: Not available

Other Physical Properties:
SAYBOLT UNIVERSAL VISCOSITY: less than 32 seconds (1)


Normally stable

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.

STRONG OXIDIZING AGENTS (e.g. peroxides, nitrates and perchlorates) - may react violently. Increased risk of fire and explosion.(5)

Hazardous Decomposition Products:

Conditions to Avoid:
Heat, open flames, static discharge, sparks and other ignition sources.

Corrosivity to Metals:
Not corrosive


No quantitative data available. n-Undecane is probably similar in toxicity to related hydrocarbons such as decane and dodecane. Toxicity by most routes probably is relatively low. Concentrated vapours may have an anesthetic effect. Anesthetic dose in mice was 100 mg/kg.(2)

Skin Irritation:

Applications of 0.5 mL of 100% n-undecane for 4 hours, under a patch, resulted in significant irritation in rabbits. Application of 50% n- undecane, under the same conditions, did not result in significant irritation.(6)

Effects of Long-Term (Chronic) Exposure:

A study on male rats showed that alkanes have a stronger effect on the kidneys as the size of the molecule increases.(2,3) Exposure to 300-900 ppm vapour of a solvent mixture containing primarily n-undecane and n-decane for up to 12 weeks caused mild kidney damage.(2,3)

Limited data available. It may act as a promoter or cocarcinogen when applied with benzo(a)pyrene (B(a)P) to the skin of mice. Application of n-undecane together with B(a)P caused papillomas on the skin, 89% of which were squamous carcinomas. n-Undecane alone had no effects.(2) The relevance of these results is unknown to humans.


Selected Bibliography:
(1) Cavender, F. Aliphatic hydrocarbons. In: Patty's industrial hygiene and toxicology. 4th edition. Volume II. Toxicology. Part B. Edited by G.D. Clayton et al. John Wiley and Sons, 1994. p. 1226-1227, 1239
(2) Kjaergaard, S., et al. n-Decane and n-undecane. In: Criteria documents from the Nordic Expert Group 1987. Edited by G. Heimburger et al. Arbete Och Halsa. No. 40 (1987). p. 45-73
(3) Low, L.K., et al. Decane, undecane and dodecane (C10-C12). In: Ethel Browning's toxicity and metabolism of industrial solvents. Vollume 1: Hydrocarbons. 2nd edition. Elsevier Science Publishers, 1987. p. 322-326
(4) Rivedal, F., et al. Effects of hydrocarbons on transformation and intercellular communication in Syrian hamster embryo cells. Pharmacology and Toxicology. Vol. 71 (1992). p. 57-61
(5) Sigma-Aldrich library of chemical safety data. Edition II. Volume 2. Sigma-Aldrich Corporation, 1988. p. 3571C
(6) Jacobs, G. et al. Evaluation of the test method for skin irritation as prescribed by OECD and EEC. Journal of Toxicology-Cutaneous and Ocular Toxicology. Vol 6, no. 3 (1987). p. 215-225
(7) Fire protection guide to hazardous materials. 13th ed. Edited by A.B. Spencer, et al. National Fire Protection Association, 2002. NFPA 325
(8) Jacobs, G.A. OECD skin irritation tests on four aliphatic hydrocarbons. Journal of the American College of Toxicology. Part B. Vol. 1 (1990). p. 57-58

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: 1997-03-12

Revision Indicators:
US transport 1998-03-01
Resistance of materials 1998-06-01
Bibliography 1998-06-01
Bibliography 2003-04-11
NFPA (health) 2003-04-11
Extinguishing media 2003-04-11
WHMIS disclosure list 2004-11-17
Bibliography 2006-04-25

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