Allergy to the azo disperse textile dyes Disperse Blue 106, Disperse Blue 124, Disperse Brown 1 and Disperse Yellow 3 was thought (following positive 48-hour covered patch tests) to be the cause of the severe dermatitis affecting the trunk, back, legs and arms of a 30-year-old French woman. She also reacted to p-aminophenol. The symptoms disappeared within 2 weeks of her avoiding wearing clothes containing synthetic fibres (usually coloured with this group of dyes). The investigators warned that the increasing use of dyed synthetic fibres could result in more frequent textile sensitization.