t205 Elder
Allergens within Tree Pollens
- Latin name: Sambucus nigra
- Family: Caprifolicaeae
- Common names: Elder, Common Elder, Elderberry
- Source material: Pollen
Sambucus is the old Latin name for the European Elderberry; nigra (black) may refer to the ripe fruit.
European species
- Sambucus niger- European Elderberry - produces sweet, black fruit.
- Sambucus racemosa - European Red Elderberry
- Sambucus ebulus
American species
- Sambucus caerulea - Blue Elderberry
- Sambucus canadensis - American Elderberry - produces sweet, black fruit.
- Sambucus pubens - American Red Elderberry - poisonous fruit
Japan
- Sambucus sieboldiana
Not to be confused with the Box Elder tree (Acer Negundo) or the Grey Alder tree (Alnus incana)
A tree species producing pollen, which may induce hayfever, asthma and conjunctivitis in sensitised individuals.
Allergen Exposure
Geographical distribution
The Elder tree, and other species of Sambucus, comprise fast-growing small trees or large shrubs, 1-4 m tall. The leaves are compound and contain 5-11 leaflets, with finely or sharply toothed margins, 4-13 cm long and 2-6 cm wide.
Numerous species of Elder tree or Elderberry grow in Europe and North America. The Elder tree is native to southeastern Canada and most of the United States except for the Great Basin and the Pacific Northwest, and is found in Britain, Europe, Iraq and Turkey.
Large clusters of creamy-white flowers are produced in summer, followed in autumn by large bunches of shiny black Elderberries. The flowers are borne in large panicles, and are insect-pollinated. The flowers are small, white, and fragrant, in flat cymes. The fruits ripen in late fall and are usually purple-black, numerous, 4-6 mm in diameter. Only blue/black berries are medicinal; the red berries produced by some species are not medicinal.
Environment
Elder trees are usually found in floodplains or rich soil. In Europe they are often seen along fencerows and ditches and stream banks. Other areas these shrubs can be found in are hedgerows, scrub, woods, roadsides and waste places. Elderberry fruits are used for making pie, jam and wine.
Unexpected exposure
Fruits should not be eaten fresh in large quantities, as they are emetic. Elder flower extract, mostly from the European species S. nigra, is made into a drink. The leaves of American Elder are toxic.
Allergens
No allergens from this plant have yet been characterised.
Potential Cross-Reactivity
An extensive cross-reactivity among the different individual species of the genus could be expected (1).
Clinical Experience
IgE mediated reactions
Asthma, allergic rhinitis and allergic conjunctivitis may be caused by Elder tree pollen.
References:
- Yman L. Botanical relations and immunological cross-reactions in pollen allergy. 2nd ed. Pharmacia Diagnostics AB. Uppsala. Sweden. 1982: ISBN 91-970475-09
2002