Lavender oil is an essential oil obtained by distillation from the flower spikes of certain species of lavender. There are over 400 types of lavender species worldwide with different scents and qualities. Two forms are distinguished, lavender flower oil, a colorless oil, insoluble in water, having a density of 0.885 g/mL; and lavender spike oil, a distillate from the herb Lavandula latifolia, having density 0.905 g/mL. Like all essential oils, it is not a pure compound; it is a complex mixture of phytochemicals, including linalool and linalyl acetate.
Pure lavender essential oil is produced through steam distillation.[1][2] This generates a greater amount of oil compared to other methods due to reduction of polar compound loss.[3] Harvest of lavender blooms is typically between late June and August.[4] The cut lavender flowers and stems are compacted into a lavender still. A boiler is then used to steam the bottom of the lavender flower filled still at a very low pressure.[1] The lavender flower pockets containing oil are broken from this heating process and a pipe of cold water is run through the center of the still.[1] The hot lavender oil vapor condenses on the cold pipe with the cold water and is collected into a holding tank where it is allowed to settle.[1] Due to polarity and densities of the water and oil, these two will separate in the holding tank whereupon the water is piped out, leaving just lavender essential oil.[5]
Lavender oil is produced around the world, with Bulgaria, France and China leading its production.[6][7]
Lavender oil has long been used as a perfume, for aromatherapy, and for skin applications.[8][9]: 184–186 Lavender oil is used in massage therapy as a way of inducing relaxation through direct skin contact.[8]
Lavender oil is chief among a number of essential oils used in aromatherapy for people with dementia. There is no good evidence to support any benefit of this treatment.[10]
Oil of spike lavender was used as a solvent in oil painting, mainly before the use of distilled turpentine became common.[11]
Lavender Oil is classified GRAS (Generally Recognized as Safe) for its intended use by the FDA. [12]
Lavender oil is poisonous, due to the components linalyl acetate and linalool, and should not be ingested. Symptoms of lavender oil poisoning include blurred vision, difficulty breathing, burning pain in the throat, burns to the eye, confusion, decreased level of consciousness, diarrhea (watery, bloody), stomach pain, vomiting, and rash.[13] In Australia, lavender oil is one of the many essential oils that have been increasingly causing cases of poisoning, mostly of children. In the period 2014-2018 there were 271 reported cases in New South Wales, accounting for 6.1% of essential oil poisoning incidents.[14]
Lavender oil has estrogenic and anti-androgenic effects and there have been reports of its use causing prepubertal gynecomastia (abnormal breast development in children).[15][16] Other potential adverse effects include a sedative effect and contact dermatitis as an allergic reaction, possibly resulting from major lavender oil constituents, camphor, terpinen-4-ol, linalool and linalyl acetate.[17][8]
A 2018 study by the National Institute of Environmental Health Sciences found four of the constituent chemicals (eucalyptol, 4-terpineol, dipentene and alpha-terpineol) are endocrine disruptors, raising concerns of potential environmental health impact from the oil.[18]
The exact composition of lavender essential oil varies from species to species but consists primarily of monoterpeneoids and sesquiterpeneoids. Of these linalool and linalyl acetate dominate, with moderate levels of lavandulyl acetate, terpinen-4-ol and lavandulol. 1,8-cineole and camphor are also present in low to moderate qualities. In all lavender oil typically contains many more than 100 compounds, although a great many of these are present at very low concentrations.[19]
The composition of lavender essential oil as obtained by chromatography:[citation needed]
Family | Composition | Lavande officinale Lavandula angustifolia |
Lavande aspic Lavandula latifolia |
---|---|---|---|
Terpenes / Monoterpenols |
Linalool |
28.92 % | 49.47 % |
α-Terpineol | 0.90% | 1.08% | |
γ-Terpineol | 0.09% | ||
Borneol | 1.43% | ||
Isoborneol | 0.82% | ||
Terpinen-4-ol | 4.32% | ||
Nerol | 0.20% | ||
Lavandulol | 0.78% | ||
Terpenes / Terpene esters |
32.98 % | ||
Geranyl acetate | 0.60% | ||
Neryl acetate | 0.32% | ||
Octene-3-yl acetate | 0.65% | ||
Lavandulyl acetate | 4.52% | ||
Terpenes / Monoterpenes |
Myrcene | 0.46% | 0.41% |
α-Pinene | 0.54% | ||
β-Pinene | 0.33% | ||
Camphene | 0.30% | ||
(E)-β-Ocimene | 3.09% | ||
(Z)-β-Ocimene | 4.44% | ||
β-Phellandrene | 0.12% | ||
Terpenes / Terpenoid oxides |
Eucalyptol (1,8-cineol) |
25.91 % | |
Terpenes / Sesquiterpenes |
β-Caryophyllene | 4.62% | 2.10% |
β-Farnesene | 2.73% | ||
Germacrene | 0.27% | ||
α-Humulene | 0.28% | ||
Ketones | Camphor |
0.85% | 13.00 % |
3-Octanone | 0.72% | ||
Cryptone |
0.35% |