Chrysanthemum allergy. Pt. II: Experimental studies on the causative agents.

Experimental studies on allergic contact dermatitis due to Chrysanthemum indicum 1. (Chrysanthemum x-morifolium) (chrysanthemum of the florists) have indicated the following results: 1. In 5 patients with allergic contact dermatitis from chrysanthemum oil of turpentine and its sensitizing compounds gave no patch test responses. No relationship between contact allergy due to chrysanthemus and to turpentine oil could be determined. 2. The pyrethrins, constituents with insecticidal activity, derived from certain Chrysanthemum species and often suspected as the causative agents, play no role in chrysanthemum allergy. 3. Tests on sensitized guinea pigs (pirl bright white strain) with flowers of chrysanthemum as well as with the two sesquiterpene lactones parthenolide and alantolactone, derived from different Composite species, gave positive patch test reactions. The results showed that parthenolide produced stronger reactions than alantolactone. 4. By thin layer chromatography neither parthenolide, nor alantolactone or pyrethrosin could be detected in extracts of chrysanthemum flowers of the florists. But the investigations indicated that several other terpenic compounds are present, which gave positive color reactions to certain lactone reagents. Five of them showed strong positive patch test reactions in our patients as well as in sensitized guinea pigs. Further studies are required to identify these compounds.