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 dermatitishas 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.
Other information:  
Patch test:  

 

Related Information

References

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