Blackwood

Author: Hon A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand, 1999.

Common name:	Australian Blackwood, Wattle or Acacia.
Botanical name:	Acacia melanoxylon
Family:	Leguminosae
Origin:	Native to south-eastern Australia.
Description:	An evergreen wattle with dense foliage, balls of cream flowers and twisted pods. Height: 20 m.

Uses	Gum arabic, derived from acacia (usually A. senegal), is used in the printing trade, and as a binding agent in the making of some medications. Gum arabic is also commonly used as a food additive. Because of its excellent timber properties, Australian blackwoods are increasingly being planted in New Zealand. Blackwood is used in making furniture, boats, musical instruments, etc.
Allergens	The allergens appear to be 2,6-dimethoxy-1,4-benzoquinone, acamelin, and melacacidin (in heartwood).
Allergy	Hand dermatitis has been reported after contact with both the wood and gum arabic. Sawdust is a problem, particularly in furniture makers. Hayfever, rhinitis, conjunctivitis and other respiratory problems are of increasing concern. The prevalence of allergy to acacias, as shown in a number of Australian and Asian studies, is increasing.
Cross-reactions	Meranti (Shorea spp.) and some kinds of Mahogany.
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References

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