Background: In the last 20 years, the hairdressing profession has undergone important modifications, mainly because of a change in the substances and techniques used and improved occupational education.
Objective: To evaluate the modifications in the hairdressing profession and its actual risk of occupational allergic contact dermatitis (OACD).
Methods: We studied all 300 hairdressers seen in our department from 1994 to 2003 and compared the results with those of a previous study of 379 hairdressers who attended our department from 1980 to 1993. All were patch-tested with the European Standard series and specific hairdressing products. As previously, most of the workers were women (93%), with a mean age (23.7 years) slightly higher than that of the workers in our previous study.
Results: We found a significant increase in the frequency of positive patch-test responses (78.3% vs 58.8%) and OACD (58% vs 48.8%) with respect to our previous study. We also observed a significant increase in sensitization to most allergens, including p-phenylenediamine base (54% vs 45.9%), 4-aminobenzene (40.7% vs 31.9%), ammonium thioglycolate (2.7% to 12.3%), ammonium persulfate (7.9% to 14.3%), p-toluenediamine sulfate (6.8% to 15.3%), p-aminodiphenylamine (2.9% to 7.7%), o-nitro-4-phenylenediamine (2.1% to 7.3%), and aminophenols (0% to 9%), whereas a decrease was found in sensitization to Disperse Orange (17% vs 32.7%) and thioglycolic acid (15.3% to 3%).
Conclusion: The high frequency and increase of sensitizations among hairdressers require urgent measures to improve protective measures and their application.