The following information has been extracted from our CHEMINFO database, which also contains hazard control and regulatory information. [More about...] [Sample Record]

Access the complete CHEMINFO database by contacting CCOHS Client Services.


CHEMINFO Record Number: 635
CCOHS Chemical Name: d-Limonene


Chemical Name French: Limonène (d-)
Chemical Name Spanish: Limoneno
CAS Registry Number: 5989-27-5
RTECS Number(s): GW6360000
EU EINECS/ELINCS Number: 227-813-5
Chemical Family: Unsaturated alicyclic hydrocarbon / cycloalkene / terpene
Molecular Formula: C10-H16
Structural Formula: CH3-C6H8-C(CH3)=CH2


Appearance and Odour:
Colourless liquid; lemon-like odour

Odour Threshold:
Not available.

Warning Properties:
Information for evaluation not available

d-Limonene is a natural component of citrus oils and some other foods. It is commercially prepared at high purity (97-99%) by extraction and distillation. d-Limonene is one of the chemical forms (isomers) of limonene and is a member of a large family of natural hydrocarbons called terpenes. The other form of limonene is called l-limonene (CHEMINFO 637). These two forms are chemically identical except that their molecular structures are mirror images of each other (optical isomers). Limonene is also available as a mixture of the d- and l- forms (CHEMINFO 636). Commercial forms can also contain other terpenes.

Uses and Occurrences:
Flavour and fragrance ingredient; intermediate in the synthesis of (-)-carvone; wetting and dispersing agent in terpene resin manufacture; preparation of sulfurized terpene lube oil additives; industrial solvent in degreasing operations; minor component of turpentine; component of essential oils (particularly citrus oils).


Colourless liquid with lemon-like odour. COMBUSTIBLE LIQUID AND VAPOUR. Vapour is heavier than air and may spread long distances. Liquid can float on water and may possibly travel to distant locations and/or spread fire. SKIN IRRITANT. Causes moderate skin irritation. SKIN SENSITIZER. May cause allergic skin reaction.


Effects of Short-Term (Acute) Exposure

Mist and vapour may cause nose and throat irritation. Specific information is not available, but the liquid was a skin irritant in an animal study.

Skin Contact:
Liquid can probably cause irritation. Specific human information is not available, but citrus peel oil, which contains about 90% d-limonene, is an irritant.(10) d-Limonene was a mild to moderate irritant in animal tests. Limonene (isomer not specified) was absorbed through the skin at 100 times the rate of water.(5)

Eye Contact:
d-Limonene is a mild eye irritant, based on animal information.

Ingestion of 20 g d-limonene caused diarrhea and a temporary increase in protein in the urine (proteinurea) in 5 male volunteers.(1) This information, in addition to the low acute toxicity in animal tests, suggests that d-limonene is not very toxic by ingestion.

Effects of Long-Term (Chronic) Exposure

Skin Sensitization:
d-Limonene is an occupational skin sensitizer. Repeated or prolonged skin contact can cause an allergic skin response (redness, swelling, itching). The allergic response is caused by oxidation products of d-limonene, which are formed upon exposure to air. d-Limonene of very high purity is not expected to produce an allergic response.
An 8% solution of d-limonene in petrolatum did not cause an allergic skin response in any of 25 volunteers tested.(2) Five of 67 people who had an allergic skin response to turpentine tested positive to 1% d-limonene.(3) Occupational exposure to celeriac has caused allergic skin responses. d-Limonene, a component of celeriac, is thought to be responsible.(9)

Patients were administered d-limonene (20 mL of a 97% solution) by a direct tube to the gallbladder, every second day, for up to 25 treatments. Following the initial 1-3 treatments, some patients complained of pain and tenderness in the abdomen and chest, nausea, vomiting and diarrhea. A two-year follow-up study showed no evidence of damage to blood, liver, kidney or pancreas.(1) The conduct of this study is not relevant to occupational exposures.
Low levels of d-limonene in the diet (about 100 ppm) have not been reported to cause adverse effects in humans. Animal tests suggest that repeated ingestion of large quantities of d-limonene may cause kidney damage.


There is no human information available. d-Limonene has produced renal tubular tumours in male rats, but not in female rats or mice. The mechanisms by which d-limonene increases the incidence of renal tubular tumours in mice is not relevant to humans. The International Agency for Research on Cancer (IARC) has determined that there is inadequate evidence for the carcinogenicity of d-limonene to humans and that there is sufficient evidence for the carcinogenicity of d-limonene to experimental animals.(19)

The International Agency for Research on Cancer (IARC) has concluded that this chemical is not classifiable as to its carcinogenicity to humans (Group 3).

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:
No human information. Limited evidence of developmental abnormalities in animals at doses that cause maternal toxicity.

Reproductive Toxicity:
No human information. Results of animal studies on reproductive toxicity could not be verified as the translation of the report was not available.

There is no human information available. The only study using live animals produced negative results and used an inappropriate route of exposure (intraperitoneal injection). Negative results have been obtained in tests using bacteria and cultured mammalian cells.

Toxicologically Synergistic Materials:
In one study, d-limonene increased the skin absorption of a drug (Keptoprofen) in rats and rabbits.(17)

Potential for Accumulation:
In humans, most d-limonene is excreted, mainly in the urine, within 2-3 days following ingestion.(4)


If symptoms are experienced, remove source of contamination or move victim to fresh air. Obtain medical advice.

Skin Contact:
Avoid direct contact. Wear chemical protective clothing, if necessary. As quickly as possible, remove contaminated clothing, shoes and leather goods (e.g. watchbands, belts). Quickly and gently blot or brush away excess chemical. Immediately wash gently and thoroughly with lukewarm, gently flowing water and non-abrasive soap for 15-20 minutes. Immediately obtain medical attention. Completely decontaminate clothing, shoes and leather goods before re-use or discard.

Eye Contact:
Avoid direct contact. Wear chemical protective gloves, if necessary. Quickly and gently blot or brush chemical off the face. Immediately flush the contaminated eye(s) with lukewarm, gently flowing water for 5 minutes, while holding the eyelid(s) open. Obtain medical advice.

NEVER give anything by mouth if victim is rapidly losing consciousness, is unconscious or convulsing. Have victim rinse mouth thoroughly with water. DO NOT INDUCE VOMITING. If vomiting occurs naturally, have victim rinse mouth with water again. Immediately obtain medical attention.

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:
48 deg C (118 deg F) (closed cup) (12)

Lower Flammable (Explosive) Limit (LFL/LEL):
0.7% at 150 deg C [limonene (dipentene)] (11)

Upper Flammable (Explosive) Limit (UFL/UEL):
6.1% at 150 deg C [limonene (dipentene)] (11)

Autoignition (Ignition) Temperature:
237 deg C (458 deg F) [limonene (dipentene)] (11)

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

Sensitivity to Static Charge:
May accumulate static charge by flow or agitation. d-Limonene vapour/air mixtures at concentrations in the flammable range can be ignited by a static spark. Information on the minimum ignition energy is not available.

Fire Hazard Summary:
COMBUSTIBLE LIQUID. Can form explosive mixtures at, or above 48 deg C. Liquid can float on water and may possibly travel to distant locations and/or spread fire.

Extinguishing Media:
Dry chemical powder, foam, polymer foam, water spray or fog.

Fire Fighting Instructions:
Water spray may be used to extinguish fires, because d-limonene can be cooled below its flash point. Water spray can be used to 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 to protect personnel attempting to stop a leak. Water spray may be used to flush spills away from exposures.

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: 2 - Intense or continued (but not chronic) exposure could cause temporary incapacitation or possible residual injury. (dipentene (limonene))
NFPA - Flammability: 2 - Must be moderately heated or exposed to relatively high ambient temperatures before ignition can occur. (dipentene (limonene)).
NFPA - Instability: 0 - Normally stable, even under fire conditions, and not reactive with water. (dipentene (limonene))


Molecular Weight: 136.26

Conversion Factor:
1 ppm = 5.56 mg/m3; 1 mg/m3 = 0.18 ppm at 25 deg C

Physical State: Liquid
Melting Point: -74 deg C (-102 deg F)
Boiling Point: 176 deg C (349 deg F)
Relative Density (Specific Gravity): 0.84 (water = 1)
Solubility in Water: Insoluble
Solubility in Other Liquids: Soluble in alcohol, ether. Insoluble in propylene glycol.
Coefficient of Oil/Water Distribution (Partition Coefficient): Not available
pH Value: Not applicable
Vapour Density: 4.70 (air = 1)
Vapour Pressure: Less than 3 mm Hg (0.40 kPa) at 14 deg C
Saturation Vapour Concentration: Less than 4000 ppm at 14 deg C (calculated)
Evaporation Rate: Not available
Critical Temperature: Not available

Other Physical Properties:
SPECIFIC OPTICAL ROTATION: +123.8 degree at 20 deg C (4)


Normally stable. Can slowly oxidize to form a film in the presence of air.(8)

Hazardous Polymerization:
Polymerization is not hazardous. May polymerize slowly in the presence of air.

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 - Increased risk of fire and explosion.
IODINE PENTAFLUORIDE AND TETRAFLUOROETHYLENE - Iodine pentafluoride reacted with limonene in a cylinder made of tetrafluoroethylene causing deflagration of the cylinder material.(11)

Hazardous Decomposition Products:
None reported

Conditions to Avoid:
Static spark, open flames and other ignition sources

Corrosivity to Metals:
Not corrosive


LD50 (oral, rat): 4400 mg/kg (male); 5200 mg/kg (female) (1)
LD50 (oral, mouse): 5600 mg/kg (male); 6600 mg/kg (female) (1)

LD50 (dermal, rabbit): greater than 5000 mg/kg (2)

Eye Irritation:

d-Limonene is a mild eye irritant.

Application of d-limonene resulted in mild eye irritation in rabbits (scored 8/110; Draize test).(21)

Skin Irritation:

d-Limonene is a moderate skin irritant.

Application of undiluted d-limonene, under a covering, to intact or abraded skin caused moderate irritation in rabbits after 24 hours.(2) In 2 other studies, application of 0.5 mL of d-limonene caused mild to moderate irritation in rabbits (erythema 1.8-2.0/4; edema 1.5-1.3/4).(15)

Effects of Short-Term (Acute) Exposure:

Skin Contact:
In two studies, a dog and cats were exposed dermally to insecticidal dips containing 78.2 percent d-limonene. Severe dermatitis was observed in the dog. At 5 and 10 times the recommended dose, excess salivation, incoordination and muscle tremors (signs typical of organophosphate poisoning) were observed in the cats. Effects were reversible within 5 hours.(13,14) In the absence of complete ingredient information, these effects cannot be directly attributed to d-limonene.

Male rats fed 150-2400 mg/kg/day, 5 days/week for 13 weeks developed kidney damage. Kidney damage was not seen in female rats fed the same doses as the male rats or in mice fed 125-2000 mg/kg/day.(4) Dogs fed 1.2-3.6 mL/kg/day (1.0-3.0 g/kg) for 6 months developed kidney damage. Vomiting, nausea and decreased body weight were also seen.(4)

The International Agency for Research on Cancer (IARC) has determined that there is sufficient evidence that d-limonene is carcinogenic to experimental animals.(19)
Male rats given 75-150 mg/kg/day by stomach tube, 5 days/week for 103 weeks developed kidney tumours. The type of tumour formed appears to be specific to male rats. Tumour incidences were not increased in female rats (300-600 mg/kg/day on the same schedule) or in male (250-500 mg/kg/day) or female (500-1000 mg/kg/day) mice.(4,16) d-Limonene has been shown to inhibit formation of some types of tumours when administered with, or following treatment with, known carcinogens.(4)

Teratogenicity, Embryotoxicity and/or Fetotoxicity:
Abnormalities in bone formation were seen in offspring of rats fed 591-2869 mg/kg/day and mice fed 591-2363 mg/kg/day d-limonene, respectively, over several days during pregnancy. Maternal toxicity was seen at the high doses.(4,5) Teratogenic effects were not observed in offspring of rabbits fed 250-1000 mg/kg/day for several days during pregnancy. The high dose was toxic to the females (6/21 died). Further details were not available.(4,5)

Reproductive Toxicity:
Repeated administration of high concentrations of d-limonene was reported to have adverse effects on female reproductive organs in rats and male reproductive organs in dogs. An English translation of this study was not available.(6)

Negative results were obtained in one study that used live animals. The route or exposure used in this study (intraperitoneal injection) is not considered relevant to human exposures.(4,19)
Negative results have also been obtained in tests using cultured mammalian cells and bacteria.(4,19)


Selected Bibliography:
(1) Igimi, H., et al. The use of d-limonene preparation as a dissolving agent of gallstones. Digestive Diseases. Vol. 21, no. 11 (Nov. 1976). p. 926-939
(2) Opdyke, D.L.J. Special issue II : monographs on fragrance raw materials. Food and Cosmetics Toxicology. Vol. 13 supplement (Dec. 1975). p. 825-826
(3) Romaguera, C., et al. Turpentine sensitization. Contact Dermatitis. Vol. 14, no. 3 (1986). p. 197
(4) Jameson, C.W. NTP technical report on the toxicology and carcinogenesis studies of d-limonene (Cas no. 5989-27-5) in F344/N rats and B6C3F1 mice (gavage studies). (NTP TR 347) National Institutes of Health, 1990
(5) Patty's industrial hygiene and toxicology. 3rd rev. ed. Vol. 2B. John Wiley & Sons, 1981. p. 3231-3232, 3236-3238, 3249-3250
(6) RTECS record for cyclohexane,1-methyl-4-(1-methylethenyl-)-,(R). Date of last update 9201
(7) Forsberg, K., et al. Quick selection guide to chemical protective clothing. 4th ed. Van Nostrand Reinhold, 2002
(8) Hawley's condensed chemical dictionary. 11th ed. Van Nostrand Reinhold, 1987. p. 701
(9) Agathos, M. Occupational dermatitis from celeriac. Contact Dermatitis. Vol. 6, no. 3 (1980). p. 225
(10) Cronin, E. Contact dermatitis. Churchill Livingstone, 1980. p. 532-534
(11) Fire protection guide to hazardous materials. 13th ed. Edited by A.B. Spencer, et al. National Fire Protection Association, 2002. NFPA 325; NFPA 491
(12) The Sigma-Aldrich library of chemical safety data. Ed. II. Vol. 1 (A-L), 1988. p. 2127A
(13) Hooser, Stephen B., et al. Effects of an insecticidal dip containing d-limonene in the cat. JAVMA. Vol. 188, no. 9 (Oct. 1986). p. 905-908
(14) Ross, Jeanne L., et al. Clinical Reports. Toxic epidermal necrolysis associated with flea dips. Vet Human Toxicol. Vol. 34, no. 1 (Feb. 1992). p. 57-61
(15) ECETOC: Technical Report no. 66. Skin irritation and corrosion. Reference chemicals data bank, Mar. 1995. p. 230-231
(16) Hard, G.C., et al. Risk assessment of d-limonene: An example of male rat-specific renal tumorigens. Critical Reviews in Toxicology. Vol. 24, no. 3 (1994). p. 231-254
(17) Okabe, H., et al. Percutaneous absorption enhancing effect and skin irritation of monocyclic monoterpenes. Drug Design and Delivery. Vol. 6 (1990). p. 229-238
(18) Workplace environmental exposure level guide. AIHA Journal. Vol. 56, no. 2, 1995. p. 202
(19) International Agency for Research on Cancer (IARC). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. Vol. 73. Some chemicals that cause tumours of the kidney or urinary bladder in rodents and some other substances. World Health Organization, 1999
(20) European Communities. Commission Directive 98/73/EC. Sept. 18, 1998
(21) Tsuji, M. Studies on d-Limonene, as gallstone solubilizer (I): General pharmacological studies. Oyo Yakuri. Vol. 8, no. 10 (1974). p. 1439-1459

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: 1992-09-14

Revision Indicators:
Fire fighting instructions 1994-01-01
Conditions to avoid 1994-01-01
Trans PEL-TWA 1993-04-01
TDG 1994-02-01
Handling 1995-10-01
US Transport 1996-06-01
Sampling 1996-06-01
Respiratory guidelines 1996-06-01
EU Risk 1999-12-01
EU Safety 1999-12-01
EU Comments 1999-12-01
Carcinogenicity 2000-06-01
Mutagenicity 2000-06-01
Toxicological info 2000-06-01
Bibliography 2003-04-14
NFPA (health) 2003-04-14
Resistance of materials for PPE 2004-03-28
EU classification 2005-02-06
Long-term exposure 2005-10-18
Bibliography 2005-10-18
Toxicological info 2005-10-18
Short-term eye contact 2005-10-18
WHMIS detailed classification 2005-10-18
Emergency overview 2005-10-18
First aid skin 2005-10-18
First aid eye 2005-10-18
Handling 2005-10-19
Fire hazard summary 2006-07-05
WHMIS proposed classification 2006-07-05

©2007 Canadian  Centre  for  Occupational  Health  &  Safety  E-mail:  Fax: (905) 572-2206  Phone: (905) 572-2981  
Mail:  250  Main  Street  East,  Hamilton  Ontario  L8N  1H6