Is benzyl alcohol a significant contact sensitizer?

Background Benzyl alcohol is a widely used preservative, solvent and fragrance material. According to published data, it is a rare sensitizer in humans. Objectives To identify characteristics and sensitization patterns of patients with positive patch test reactions to benzyl alcohol and to check the reliability of the patch test preparation benzyl alcohol 1% pet. Patients and Methods Retrospective analysis of data from the Information Network of Departments of Dermatology (IVDK), 2010-2019. Results Of 70 867 patients patch tested with benzyl alcohol 1% pet., 146 (0.21%) showed a positive reaction, most of them (89%) only weakly positive. The number of doubtful and irritant reactions significantly exceeded the number of positive reactions. Reproducibility of positive test reactions was low. Among benzyl alcohol-positive patients, compared to benzyl alcohol-negative patients, there were significantly more patients with leg dermatitis (17.8% vs. 8.6%), more patients aged 40 years or more (81.5% vs. 70.5%) and more patients who were tested because of a suspected intolerance reaction to topical medications (34.9% vs. 16.6%). Concomitant positive reactions were mainly seen to fragrances, preservatives and ointment bases. Conclusions Sensitization to benzyl alcohol occurs very rarely, mainly in patients with stasis dermatitis. In view of our results, benzyl alcohol cannot be regarded as a significant contact allergen, and therefore marking it as skin sensitizer 1B and labelling it with H 317 is not helpful.