Eucalyptus oil is the generic name for distilled oil from the leaf of Eucalyptus, a genus of the plant family Myrtaceae native to Australia and cultivated worldwide. Eucalyptus oil has a history of wide application, as a pharmaceutical, antiseptic, repellent, flavouring, fragrance and industrial uses. The leaves of selected Eucalyptus species are steam distilled to extract eucalyptus oil.
Eucalyptus oils in the trade are categorized into three broad types according to their composition and main end-use: medicinal, perfumery and industrial. The most prevalent is the standard cineole-based "oil of eucalyptus", a colourless mobile liquid (yellow with age) with a penetrating, camphoraceous, woody-sweet scent.
China produces about 75% of the world trade, but most of this is derived from the cineole fractions of camphor laurel rather than being true eucalyptus oil. Significant producers of true eucalyptus include South Africa, Portugal, Spain, Brazil, Australia, Chile, and Eswatini.
Global production is dominated by Eucalyptus globulus. However, Eucalyptus kochii and Eucalyptus polybractea have the highest cineole content, ranging from 80 to 95%. The British Pharmacopoeia states that the oil must have a minimum cineole content of 70% if it is pharmaceutical grade. Rectification is used to bring lower grade oils up to the high cineole standard required. In 1991, global annual production was estimated at 3,000 tonnes for the medicinal eucalyptus oil with another 1500 tonnes for the main perfumery oil (produced from Eucalyptus citriodora).The eucalyptus genus also produces non-cineole oils, including piperitone, phellandrene, citral, methyl cinnamate and geranyl acetate.
The European Medicines Agency Committee on Herbal Medicinal Products concluded that traditional medicines based on eucalyptus oil can be used for treating cough associated with the common cold, and to relieve symptoms of localized muscle pain.
Eucalyptus oil is used in flavouring. Cineole-based eucalyptus oil is used as a flavouring at low levels (0.002%) in various products, including baked goods, confectionery, meat products and beverages. Eucalyptus oil has antimicrobial activity against a broad range of foodborne human pathogens and food spoilage microorganisms. Non-cineole peppermint gum, strawberry gum and lemon ironbark are also used as flavouring. Eucalyptus oil is also used as a fragrance component to impart a fresh and clean aroma in soaps, detergents, lotions, and perfumes. It is known for its pungent, intoxicating scent. Due to its cleansing properties, Eucalyptus oil is found in mouthrinses to freshen breath.
Research shows that cineole-based eucalyptus oil (5% of mixture) prevents the separation problem with ethanol and petrol fuel blends. Eucalyptus oil also has a respectable octane rating and can be used as a fuel in its own right. However, production costs are currently too high for the oil to be economically viable as a fuel.
If consumed internally at low dosage as a flavouring component or in pharmaceutical products at the recommended rate, cineole-based 'oil of eucalyptus' is safe for adults. However, systemic toxicity can result from ingestion or topical application at higher than recommended doses. In Australia, eucalyptus 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 2049 reported cases in New South Wales, accounting for 46.4% of essential oil poisoning incidents.
The probable lethal dose of pure eucalyptus oil for an adult is in the range of 0.05 mL to 0.5 mL/per kg of body weight. Because of their high body-surface-area-to-mass ratio, children are more vulnerable to poisons absorbed transdermally. Severe poisoning has occurred in children after ingestion of 4 mL to 5 mL of eucalyptus oil.
Dennis Considen and John White, surgeons on the First Fleet, distilled eucalyptus oil from Eucalyptus piperita found growing on the shores of Port Jackson in 1788 to treat convicts and marines. Eucalyptus oil was subsequently extracted by early colonists, but was not commercially exploited for some time.
Baron Ferdinand von Mueller, Victorian botanist, promoted the qualities of Eucalyptus as a disinfectant in "fever districts", and also encouraged Joseph Bosisto, a Melbourne pharmacist, to investigate the commercial potential of the oil. Bosisto started the commercial eucalyptus oil industry in 1852 near Dandenong, Victoria, Australia, when he set up a distillation plant and extracted the essential oil from the cineole chemotype of Eucalyptus radiata. This resulted in the cineole chemotype becoming the generic 'oil of eucalyptus', and "Bosisto's Eucalyptus Oil" still survives as a brand.
Eucalyptus oil became an important industry in the box-ironbark forests of Victoria during the post gold-rush era of the 1870s. The oil was often described as Australia's natural wonder and was exported to a growing international market, mostly for medicinal purposes. Eucalyptus oil was in particularly big demand during the global influenza pandemic of 1918-19. A distillation plant was established by the Forests Commission Victoria at Wellsford State Forest near Bendigo in 1926. The Principal of the Victorian School of Forestry, Edwin James Semmens, undertook much of the pioneering chemistry into the composition of eucalyptus oil. His steam extraction kilns are in the museum at the school.
The Australian eucalyptus oil industry peaked in the 1940s, the main area of production being the central goldfields region of Victoria, particularly Inglewood; then the global establishment of eucalyptus plantations for timber resulted in increased volumes of eucalyptus oil as a plantation by-product. By the 1950s the cost of producing eucalyptus oil in Australia had increased so much that it could not compete against cheaper Spanish and Portuguese oils (closer to European Market therefore less costs). Non-Australian sources now dominate commercial eucalyptus oil supply, although Australia continues to produce high grade oils, mainly from blue mallee (E. polybractea) stands.
In one clinical trial, people who breathed in eucalyptus oil after knee replacement surgery felt less pain and had lower blood pressure. Researchers think this may be due to something in the oil called 1,8-cineole. It may make your sense of smell work with your nervous system to lower your blood pressure.
Eucalyptus oil not only can help with pain post-op, but it also may help keep you calm before surgery, too. Researchers measured the effect on anxiety of breathing in essential oils in people about to have surgery. Before their operations, they smelled different oils for 5 minutes. The 1,8-cineole in eucalyptus oil worked so well that researchers suggested it may be useful for entire procedures.
Take this, lice. A treatment of eucalyptus and tea tree oil did twice as well in a clinical trial as the old standby, pyrethrin. Not only did it kill 100% of lice and eggs, but it did it in only one dose. Other treatments needed several. Tests on skin revealed no irritation for adults or children, too.
Eucalyptus oil shows promise as a defense against HSV-1, or oral herpes. In one lab study, it outperformed the standard herpes medication, acyclovir. The 1,8-cineole chemical in the oil shuts down virus particles and may block them from entering cells. In lab tests, eucalyptus oil was able to curb the spread of the virus by more than 96%.
Though eucalyptus oil has many benefits, the undiluted form can be highly toxic if you take it by mouth. Just 2-3 milliliters can trigger dizziness, drowsiness, and loss of muscle control. Five milliliters or more can lead to nervous system shutdown and even coma. Symptoms show up between 30 minutes to 4 hours after exposure. A small number of people have had epileptic-like seizures within a few minutes of inhaling eucalyptus oil.
The leaves are dried, crushed, and distilled to release the essential oil. After the oil has been extracted, it must be diluted before it can be used as medicine. Here are nine benefits of eucalyptus oil.
For many years, eucalyptus oil has been used to relieve coughing. Today, some over-the-counter cough medications have eucalyptus oil as one of their active ingredients. Vicks VapoRub, for example, contains about 1.2 percent eucalyptus oil along with other cough suppressant ingredients.
The Australian aborigines used eucalyptus leaves to treat wounds and prevent infection. Today the diluted oil may still be used on the skin to fight inflammation and promote healing. You can purchase creams or ointments that contain eucalyptus oil. These products may be used on minor burns or other injuries that can be treated at home.
Respiratory conditions such as asthma and sinusitis may be helped by inhaling steam with added eucalyptus oil. The oil reacts with mucous membranes, not only reducing mucus but helping loosen it so that you can cough it up.
Research suggests that eucalyptus oil eases joint pain. In fact, many popular over-the- counter creams and ointments used to soothe pain from conditions like osteoarthritis and rheumatoid arthritis contain this essential oil.
Eucalyptus oil is made from leaves of selected eucalyptus tree species. The trees belong to the plant family Myrtaceae, which is native to Australia, Tasmania and nearby islands. There are more than 500 eucalypti species, but essential oils of Eucalyptus salicifolia and Eucalyptus globulus (which is also called fever tree or gum tree) are retrieved for their medicinal properties.
Traditionally, eucalyptus oil was used as an analgesic agent that helped to relieve pain, and it was valued for its ability to reduce inflammation and improve respiratory conditions. And today, eucalyptus oil benefits and uses are extensive, and the oil is commonly used in healing ointments, perfumes, vapor rubs and cleaning products. 041b061a72