Rosemary Morocco Essential Oil (Rosmarinus Officinalis)

Key constituents

a-Pinene 24.0–28.5%

Bornyl acetate 11.5–14.3%

1,8-Cineole 6.8–13.6%

Camphor 9.9–10.4%

Borneol 5.0–8.4%

Camphene 5.9–7.0%

Verbenone 4.3–5.7%

(þ)-Limonene 4.1–4.6%

b-Pinene 2.2–2.9%

b-Myrcene 1.7–2.4%

p-Cymene 1.1–2.4%

Linalool 1.4–2.1%

Terpinen-4-ol 0.7–1.4%

a-Terpineol 0.8–1.2%

1-Octen-3-ol 0–1.1%

Quality  Rosemary oil may be adulterated with eucalyptus oil, white camphor oil, turpentine oil and  fractions thereof

Safety summary
Hazards  May be neurotoxic, based on camphor content
Contraindications  Do not apply to or near the face of infants or children.
Maximum use levels Camphor CT 16.5% ; 513 mg

Our safety advice
The maximum doses recommended above for the camphor and a-pinene CT oils are based on camphor contents of 27.3% and 20.7%, respectively, and dermal and oral limits of 4.5% and 2 mg/kg/day. The verbenone chemotype limits are based on 14.9% camphor and 2.9% isopinocamphone, with limits of 0.24% and 0.1 mg/ kg/day for isopinocamphone.
Regulatory guidelines Has GRAS status.

Organ-specific effects
Adverse skin reactions  Undiluted rosemary oil was moderately irritating to rabbits; tested at 10% on 25 volunteers it was neither irritating nor sensitizing; it is non-phototoxic. In a study of 200 consecutive dermatitis patients, none were sensitive to 2% rosemary oil on patch testing.

Cardiovascular effects In normal rabbits, 25 mg/kg im rosemary oil produced 20–55% increases in plasma glucose levels after 60–120 minutes, and a 30% decrease in serum insulin levels. In spite of being contraindicated for people with high blood pressure in several aromatherapy books there is no evidence that rosemary oil is hypertensive.

Reproductive toxicity  The low reproductive toxicity of camphor, 1,8-cineole, a-pinene, b-myrcene and (þ)-limonene suggest that most rosemary oils are not hazardous in pregnancy. However, bornyl acetate and verbenone have not been studied.

Systemic effects
Acute toxicity  Rosemary oil acute oral LD50 in rats 5 mL/kg; acute dermal LD50 in rabbits >10 mL/kg. Rosemary oil was not significantly cytotoxic to cultured human umbilical vein endothelial cells. Camphor is potentially neurotoxic and may be more toxic in humans than in rodents. Camphor minimum LD50 is1.7 g/kg in rats. 1,8-Cineole has been reported to cause serious poisoning in young children when accidentally instilled into the nose.

Antioxidant/pro-oxidant activity  Rosemary oil showed high antioxidant activity as a DPPH radical scavenger and against lipid peroxidation. A rosemary oil showed high antioxidant activity in the same two assays.

Carcinogenic/anticarcinogenic potential  Orally administered rosemary oil  was hepatoprotective in rats and antimutagenic in Swiss mice. The antimutagenic dose of 1,100 mg/kg/day for seven days prevented the formation of micronuclei. In a similar study, there was a significant increase in micronuclei in Swiss mice given a single dose of 1,000 or 2,000 mg/kg, but there was no genotoxicity in a group on 300 mg/kg. However, a comet assay found all three doses to be genotoxic. Rosemary oil induced apoptosis in human liver cancer cells.

Drug interactions  Given to male rats in their diet at 0.5% for two weeks, rosemary oil selectively induced CYP2B1 and CYP2B2 in rat liver. This high-dose regimen does not suggest a significant risk of drug interaction.

Comments
Many of the above studies do not specify which chemotype was used. Rosemary oil is produced in many parts of the world, and this summary of chemotypes may not represent every type of commercial oil. 1,8-Cineole chemotypes tend to be Moroccan or Tunisian, a-pinene chemotypes are often from Spain bornyl acetate chemotypes may be French, myrcene chemotypes are probably Portuguese and verbenone chemotypes are generally Egyptian. Rosemary oils are also  produced in England, Russia, Germany, Romania and the Balkans. Most research papers do not identify the type of rosemary oil used.