Selected oxidized fragrance terpenes are common contact allergens

Abstract

Terpenes are widely used fragrance compounds in fine fragrances, but also in domestic and occupational products. Terpenes oxidize easily due to autoxidation on air exposure. Previous studies have shown that limonene, linalool and caryophyllene are not allergenic themselves but readily form allergenic products on air-exposure. This study aimed to determine the frequency and characteristics of allergic reactions to selected oxidized fragrance terpenes other than limonene. In total 1511 consecutive dermatitis patients in 6 European dermatology centres were patch tested with oxidized fragrance terpenes and some oxidation fractions and compounds. Oxidized linalool and its hydroperoxide fraction were found to be common contact allergens. Of the patients tested, 1.3% showed a positive reaction to oxidized linalool and 1.1% to the hydroperoxide fraction. About 0.5% of the patients reacted to oxidized caryophyllene whereas 1 patient reacted to oxidized myrcene. Of the patients reacting to the oxidized terpenes, 58% had fragrance-related contact allergy and/or a positive history for adverse reaction to fragrances. Autoxidation of fragrance terpenes contributes greatly to fragrance allergy, which emphasizes the need of testing with compounds that patients are actually exposed to and not only with the ingredients originally applied in commercial formulations.

Biosynthesis and Therapeutic Properties ofLavandulaEssential Oil Constituents

“…While linalool itself may have limited allergenic properties, it can auto-oxidize upon air exposure into a hyperoxide species [21] which can lead to contact allergy responses in mice [22]. In a study of 1511 dermatitis patients, auto-oxidized linalool was shown to induce allergenic responses in 1.3 % of those tested, with 1.1 % of patients sensitive to the linalool hyperoxide fraction, using patch tests [23]. A follow-up study, again involving 1511 dermatitis patients, showed that exposure to oxidized linalool at concentrations of > 6.0 % resulted in allergenic irritation in 5-7% of test subjects [24].…”

Aqueous Solubility of Liquid Monoterpenes at 293 K and Relationship with Calculated Log P Value

“…9,10) In experimental dermopharmacy terpenes are widely used as penetration enhancers. 11) The structure of investigated terpenes is presented in Table 1.…”

Chromatographic Evaluation of Terpenoids of some medicinally important barks

“…[23] Kwon-Ghung and Bennette, [24] studied the pathogenic aspects of Aspergillus, responsible for most human systemic infections. Matura et al [25] investigated the role of some terpens play as causative agents of contact dermatitis and fragrance allergies. Our results indicate that, there is decrease in terpenoid pool with ageing of the bark.…”