An Update on Fragrance Contact Dermatitis

Abstract

Fragrances are a group of substances present in many cosmetic products, which are one of the most common sources of allergic contact dermatitis (ACD) in Europe. Their widespread distribution, the presence of these substances as combinations, their ability to transform into more reactive substances, and the relatively recent regulations regarding these products are the main reasons for this high prevalence. In the last few years, advances on knowledge about haptens in fragrances have made possible to discover new allergens, to state that current fragrance markers are not enough to detect most of fragrance ACD cases and to know the products that should be patched and their concentrations. In this review, we revise the mechanisms of sensitization to allergens that are not represented in baseline series and the concentrations at which they should be used, which should be included in specific series and the usefulness of baseline and fragrance specific series. To revise the most recent advances in knowledge about fragrance contact dermatitis, especially about sensitization mechanisms and effectivity of fragrance markers in baseline series and fragrances in essential oils. Fragrance allergic contact dermatitis (ACD) is one of the most common sources of ACD only preceded by nickel sulfate. Many studies have shown that fragrance mix (FM)I, FMII, and colophonium, fragrance markers in baseline series, are not enough to screen for cases of ACD to fragrances. Some fragrances use limonene and linalool hydroperoxides, which have shown a high prevalence of sensitization and have been proposed as new allergens to include in the European Baseline Series, while other fragrances like Evernia furfuracea, which have also shown a high prevalence of sensitization, will not be included. Essential oils are obtained by distillation process and are widely used. In some cases, their allergenic components are not known. Co-sensitization to other fragrance components is frequent and they should be patch tested if allergic contact dermatitis to fragrances or cosmetics is suspected. A more extensive group of fragrance markers should be included in the European Baseline Series, with at least limonene and linalool hydroperoxides and Evernia furfuracea. The use of products containing fragrances is very common and people sensitized to one of these substances should be suspected of multiple co-sensitizations.