[Airborne contact dermatitis].

Two elderly individuals suffering from acute recurrent dermatitis of light-exposed skin between spring and autumn were shown to be allergic to feverfew (Tanacetum parthenium) of the Compositae family. Patch tests revealed not only strong reactions to the plant and its constituent parthenolide but also a number of cross-reactions to related species. The source of this contact allergy was dried airborne plant particles that attached themselves to the skin during long periods outdoors. Differentiation between patterns of airborne contact dermatitis and persistent light reaction is possible by several distinct observations, i.e., in patients with airborne contact dermatitis: a) Patch tests with Compositae plant extracts and constituents will be positive. b) There will be no skin lesions in winter. c) Skin regions that are usually not impaired during light exposure will also be involved: the upper eyelids, the retroauricular region, the shady area beneath the chin.