Textile Dyes Disperse Orange 1 and Yellow 3 Contain More Than One Allergen As Shown by Patch Testing with Thin-Layer Chromatograms

Background:
It is known that some patch-test preparations containing disperse dyes contain impurities with unknown relevance for the development or elicitation of contact allergy.

Objective:
To evaluate the significance of the impurities found in the commercial dyes Disperse Orange 1 (DO1) and Disperse Yellow 3 (DY3) regarding contact allergy in patients with known sensitivity to them.

Methods:
Ten patients allergic to DY3 and/or DO1 were tested with a dilution series of commercial and purified DY3 and DO1 (with water-soluble parts prepared from the commercial dyes) and with naphthalene sulfonate. Nine patients were additionally tested with thin-layer chromatograms (TLCs) made from the commercial DO1 and DY3 and with paper chromatograms made from the water-soluble part of these dyes.

Results:
Eight of nine and three of six patients tested positively to the TLCs of DO1 and DY3, respectively. Among them, 4 of 8 and 2 of 3 patients, respectively, were positive also to another spot on the TLCs. One patient was positive to the paper chromatogram from the water-soluble part of DO1. None of the tested patients reacted to naphthalene sulfonate.

Conclusion:
The results of our study suggest that there are more relevant allergens in the fat-soluble and water-soluble fractions of the commercial disperse dyes.