Twenty Years of Contact Allergy in Danish Cleaners: A Matched Cross-Sectional Study

Background: Cleaners are affected by occupational contact dermatitis, with both allergic and irritant causes. More knowledge on contact allergy in cleaners is needed for better preventive measures.Objectives: To investigate which contact allergens from the European baseline series (EBS) are associated with the cleaning profession.Method: A matched cross-sectional study using data from the Allergen database at Gentofte Hospital, Copenhagen, Denmark, in the period 2003-2023 was conducted. Patch tested cleaners were matched with patch tested noncleaners (controls) at a 1:4 ratio based on age (±4 years), sex, and the year of patch test.Results: In total, 459 cleaners and 1836 matched controls were included in the study. Being a cleaner was significantly positively associated with hand dermatitis and occupational dermatitis and significantly negatively associated with facial dermatitis and atopic dermatitis. Among the allergens from the EBS, thiuram mix and nickel were significantly positively associated with being a cleaner.Conclusion: Future prevention programs for cleaners should have a focus on contact allergy, including information on rubber accelerators and correct use of gloves.