Pilot Study of the Prevalence of Contact Sensitization to Preservatives as Cosmetic Ingredients in Occupational and Educational Exposures

Abstract Aim: To evaluate the prevalence of contact sensitization to selected preservatives as cosmetic ingredients among cosmeticians and cosmetology students and to identify the most common allergens in occupational and non-occupational exposures. Materials and methods: Skin patch testing with formaldehyde, quaternium-15, DMDM hydantoin, imidazolidinyl urea, methylisothiazolinone + methylchloro-isothiazolinone, iodopropynyl butylcarbamate, methyldibromoglutaronitrile, polyaminopropyl biguanide and paraben mix was performed among 109 participants – 37 cosmetology students, 26 cosmeticians, and 46 individuals – controls, occupationally unexposed to cosmetics. Fisher Exact Test and multiple binary logistic regression analysis were used. Results: Formaldehyde was the main contact sensitizer, with significantly higher prevalence of sensitization among the occupationally exposed cosmeticians and cosmetology students if compared to the controls (p = 0.005) [OR = 0.290 (95% CI: 0.092-0.916]). The positivity prevalence to DMDM hydantoin was 11%, with equal rates of sensitization to quaternium-15, methylisothiazolinone + methylchloroisothiazolinone and methyldibromo-glutaronitrile (9.2%). A significantly higher prevalence of co-sensitization to DMDM hydantoin and imidazolidinyl urea was revealed. The positivity rate to quaternium-15 was highest among cosmetology students – 13.5%. The frequency of positive reactions to imidazolidinyl urea was 2.7% for students and 11.5% for cosmeticians. Cosmetology students and cosmeticians were at risk of sensitization to DMDM hydantoin, and the cosmeticians – to methylisothiazolinone/methylchloro-isothiazolinone and methyldibromo glutaronitrile and parabens. Conclusions: This study established comparative high prevalence and risk of contact sensitization to the selected preservatives. Proper occupational risk information, developing and disseminating of practical tools for workplace risk assessment and management, with complex programs for prevention of occupational skin diseases should be provided.