The prevalence of contact
allergy to the fragrance mix in individuals with
eczema is up to 10%. Within the mix,
isoeugenol (CAS 97-54-1) is an important individual
allergen. Until May 1998, the IFRA (International Fragrance Association) guidelines suggested that
isoeugenol could safely be used at a level of 0.2% in consumer products. In May 1998, IFRA recommended that
isoeugenol should not be used at a level that exceeds 0.02% in consumer products, but did not provide guidance on
allergen substitution. An alternative to
isoeugenol, based on aroma and absence of guidelines on use, is
isoeugenyl acetate (CAS 93-29-8). 155 consecutive subjects were patch tested to
isoeugenyl acetate (1.2%, 0.4%, 0.13% eth.) and
isoeugenol 1% pet. 6 (3.9%) had an
allergic reaction to 1.2%
isoeugenyl acetate at D4. The reactions to the other 2 dilutions tended to be graded. 8 individuals had at least a palpable
erythema by D4 to
isoeugenol 1% pet. The majority of individuals allergic to
isoeugenol were also intolerant of
isoeugenyl acetate. Effective labelling of fragrance substances on consumer products will facilitate monitoring of exposure.