Myrtaceae
Eucalyptus globulus
Tasmanian blue gum · Southern blue gum
- Part used
- leafoil
- Native range
- Tasmania and southern Victoria; planted for timber and oil across the world and invasive in several countries
- Morphology
- A tall tree to seventy metres, with juvenile leaves rounded and blue-grey and adult leaves long, sickle-shaped and pendulous. The bud cap and the ribbed woody fruit give it its name.
What is in it
Evidence
1,8-cineole has reasonable evidence as an expectorant and in sinusitis and bronchitis, and appears in registered medicines. Inhaled and topical uses are better supported than anything swallowed.
Safety
Eucalyptus oil ingestion is a leading cause of paediatric poisoning in Australia, and as little as five millilitres has caused serious toxicity in a child. Presents with ataxia, vomiting, drowsiness, seizures and respiratory depression. Should never be applied to the face or nostrils of infants, where it can cause laryngospasm. Australian poisons centres field calls about it constantly.
Interactions: Induces drug-metabolising enzymes at high exposure
Regulatory: Permitted in registered medicines at controlled concentrations. Child-resistant packaging is mandatory in Australia.
Historical use
Used by Aboriginal peoples across its range, including as a fumigant and for wounds. Commercial distillation began in Victoria in the 1850s under Joseph Bosisto, and eucalyptus oil became one of colonial Australia’s first manufactured exports.
Recorded as history and attributed where possible. Long use establishes that a plant was widely used, not that it worked, and not that it was safe.
Worth knowing
Eucalyptus oil is the single commonest serious plant poisoning of Australian children, and the reason is that it is in almost every house and does not look like a medicine.
It is sold in supermarkets for laundry and cleaning, kept in bathroom cabinets, and used in vaporisers. A small swallow is enough to cause seizures in a toddler. Child-resistant packaging became mandatory precisely because of the case numbers, and the calls to poisons centres continue anyway.
The commercial story is also a piece of colonial industrial history: Bosisto's Victorian distillery in the 1850s made eucalyptus oil one of the first manufactured goods Australia exported, built on a tree whose properties Aboriginal people had been using for a very long time.
Nomenclature verified against GBIF backbone taxonomy.