Contact allergy to Disperse Blue 106 and Blue 124 in black "velvet" clothes

9 cases of allergic contact dermatitis due to black "velvet" fabrics, mostly leggings, are reported. In all cases, the 2 disperse dyes Blue 106 and 124 were shown to be the responsible contact sensitizers. Preparation of a chloroform extract and separation of the different disperse dyes by analytical and preparative thin-layer chromatography showed that 8 of the 9 black "velvet" clothes contained the same composition, namely Disperse Blue 1, 106, and 124, Disperse Red 1 and Disperse Yellow 3. In experimental studies performed previously. Disperse Blue 124 has been demonstrated to be a moderate sensitizer while Disperse Blue 106 proved to be the strongest found so far among the azo disperse dyes.