Linalool and d-limonene are common fragrance ingredients that readily oxidize on exposure to air. The resulting hydroperoxides of linalool and d-limonene have been shown to have high frequencies of positive patch test reactions in several European and international studies.
The aim of the study was to investigate the prevalence of contact allergy to the hydroperoxides of linalool and d-limonene in a US population.
In this retrospective study, 103 patients with suspected fragrance allergy were patch tested to linalool 10% petrolatum (pet), hydroperoxides of linalool 1% pet, d-limonene 10% pet, and/or the hydroperoxides of d-limonene 0.3% pet between July 9, 2014, and October 25, 2016.
In this study, the frequency of positive patch test reactions to the hydroperoxides of linalool is 20% (19/96), and the frequency of positive reactions to the hydroperoxides of d-limonene is 8% (7/90). These high frequencies suggest that patch testing to the hydroperoxides of linalool and limonene should be performed in all patients with suspected fragrance allergy.