The aim of this study was to assess the strength of any association between sensitization to 'new' fragrance compounds and sensitization to Compositae, fragrance mix, Myroxylon pereirae resin and
colophonium, respectively. Consecutive
eczema patients were tested with a series of
essential oils and selected fragrance compounds and another series of oxidized
terpenes in connection with European multicentre fragrance projects. Contact
allergy to either series was frequently detected, in 5% of 318 and 4.6% of 262 persons tested, and both had a statistically significant association with Compositae,
colophonium and fragrance mix sensitization. The individual results indicated that simultaneously occurring positive reactions to
essential oils,
colophonium and Compositae were based on cross-reactivity rather than concomitant sensitization. Thus, all patients with positive reaction to the rare fragrance sensitizer
beta-caryophyllene had positive
colophonium reactions, and cross-reactivity between
essential oils and Compositae was related to the Compositae
plant extracts of the Compositae mix and not the pure
sesquiterpene lactones of the standard series. The implication is that Compositae mix and
colophonium may be markers of fragrance
allergy, which is important to know when assessing the relevance of positive reactions to Compositae
plant extracts and
colophonium.