Fragrances have become ubiquitous in skin and hair care products to appeal to the consumer’s senses. However, fragrances have been associated with allergic contact dermatitis in applications including: unspecified leave-on products, sun tan lotion, deodorants, scented lotion, unspecified rinse-off products, fine fragrances, shampoo, liquid soap, aftershave, lipstick, sunscreen, hair styling products, shaving foam, mascara, hair dye, eye shadow and makeup cream. While some dermatologists recommend avoiding all fragrances yielding positive patch test results, it has become increasingly difficult to avoid all fragrances and in the end, may be unnecessary for the patch test positive patient.
To identify dermatitis caused by fragrance, a patch test for common aromatic allergens was designed in which two fragrance mixes using putative common allergens served as screens. Fragrance Mix #1 (FM1) was developed from the fragrances used in an antifungal cream that had caused an allergic contact dermatitis epidemic. It comprised: Evernia prunastri (oak moss), isoeugenol, cinnamyl alcohol, eugenol, cinnamal, geraniol, α-amylcinnamal and hydroxycitronellal. Fragrance Mix #2 (FM2), a later attempt5 to identify fragrance allergens, consisted of hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC), farnesol, citral, hexyl cinnamal, citronellol and coumarin. These materials are considered EU fragrance allergens and have been used in fragrance allergy testing reported in the literature, which are reviewed here.
The diagnosis of a fragrance contact allergy always starts with a detailed medical history. Schollhammer et al. developed a questionnaire to determine if consumers had a “certain, probable or possible” allergy to fragrances based on their recollection of adverse reactions to perfumes or perfumed products. In this questionnaire, the “certain” allergy included an itching dermatitis reaction to at least one fine perfume or aftershave, and reactions to other perfumed products. The “probable” allergy involved reacting to one or more perfumed products (e.g., deodorant) but no specific perfume being identified as causing the clinical reaction. The “possible” allergy meant reacting to various cosmetic products with and without perfume, where materials other than fragrance constituted the possible cause of the reaction. Finally, those identified without a fragrance allergy had never reacted to a perfumed material.