Contact dermatitis in hairdressers' clients.

The aim of our study was to report the frequency of sensitization to hairdressing allergens in a group of patients with contact dermatitis, in whom previous treatments with hair dyes or permanent wave solutions were suspected to be the cause. 49 of 261 hairdressers' clients (18.7%), who were patch tested with the hairdressers' screening series in the years 1985-1990, showed one (27) or more (22) positive reactions to hairdressing chemicals. This study confirms hair dyeing to be the procedure associated with the highest risk of sensitization among hairdressers' clients. Among hair dye allergens, PPD is the most frequent sensitizer (7.3%). A low rate of sensitization to the PPD derivatives PAP, ONPPD and PTD was detected in these clients, there being no differences in the frequency of sensitization to the 3 substances (4.2%, 4.6% and 4.6%, respectively). Only 0.4% of clients were positive to resorcinol, while pyrogallol showed a 2.3% rate of sensitization. Sensitization to GMTG was found in 3.3% of patients. ATG was an infrequent sensitizer (1.1%). Allergic contact dermatitis due to APS is quite rare (2.7%), in view of the widespread use of this compound. A positive open patch test in 1 hairdressers' client, who complained of generalized urticaria after hair bleaching, confirmed the diagnosis of immediate contact reaction due to APS. Sensitization to hairdressing allergens among consumers (18.7%) is possibly more frequent than sensitization to other cosmetic ingredients. We previously detected a 14.3% rate of sensitization to cosmetic ingredients in patients with suspected allergic contact dermatitis caused by cosmetics. On the other hand, reactions to cosmetic ingredients were also common in our patients. This may indicate that hairdressers' clients make greater use of cosmetics than average.