General Description
Tea tree is a small evergreen tree, reaching roughly 7 meters in
height, native to swampy, low-lying areas of Australia. The tree
has white, paper-thin bark and narrow, dark green, aromatic leaves.
Tea tree has tiny yellowish blossoms, which grow in clusters resembling
bottle brushes, and small, non-fleshy, capsular fruit, each of which
may contain over a hundred miniscule seeds. The pungent essential
oil from the leaves is used topically for medicinal purposes.
Health Applications
- Acne
- Antibacterial
- Antifungal
History and Traditional Use
The documented history of tea tree begins in 1770, when Sir Joseph
Banks, a botanist aboard Captain James Cook's Endeavor, first
came upon the tree, naming it "tea tree" because the crew had
used its leaves as a substitute for tea. Although Australian Aborigines
used tea tree leaves for a variety of folk remedies, the herb
remained relatively obscure until World War I, when Australian
troops were given tea tree oil for use as a disinfectant. In the
early 1920s, tea tree oil was studied extensively by Arthur Penfold,
a government research scientist in New South Wales, who found
it to be several times more effective than the most commonly used
antiseptics of the time. Tea tree oil was used widely in the following
decades, but fell out of popular use after World War II, when
synthetic antiseptics became available.
Chemical Composition
Tea tree oil contains at least 48 identified compounds, of which
terpenes and sesquiterpenes are believed to be the most active.
Antimicrobial Activity
Tea tree oil has been regaining some of its former popularity
as a topical antiseptic/disinfectant, and research tends to support
such use. In numerous studies, tea tree oil has demonstrated the
ability to kill a variety of bacteria,1-5
yeast,6-8 protozoa,9 and
fungi.5,8,10,11 Human studies indicate that
tea tree oil may be useful in the treatment of burn wounds,12
yeast infections,7 acne,13
athletes foot,14 and toenail fungal infection.15
Dosage/Toxicity
For topical uses, tea tree oil can be applied liberally with no
toxic effects. While tea tree oil is nonirritating for most people,
individuals with sensitive skin may want to dilute it with a neutral
oil such as almond oil or mineral oil. Tea tree oil is not recommended
for internal use. It has produced signs of toxicity when ingested,16
and should be stored out of reach of children. |
