CONTACT ALLERGY TO AN OPTICAL WHITENER, “CPY”, IN WASHING POWDERS

Abstract

SUMMARY.— In 16 months contact dermatitis from an optical whitener, Tinopal CH 3566, was diagnosed in 167 patients at the Finsen Institute. The dermatitis presented as a textile dermatitis. Since “Tinopal” covers a wide range of chemically unrelated optical whiteners, the designation “CPY” is introduced for the particular pyrazoline derivative implicated in this dermatitis. This product sensitized 16 of 20 animals in the guinea‐pig maximization test: this rates this optical whitener as a strong sensitizer. The result of patch testing in some of the patients with a number of pyrazoline derivatives points to the 4‐position in the pyrazoline ring and the para‐position in the l‐benzyl‐ring as key positions. Benzylsalicylate evoked a positive reaction in 16 of 88 patients. Seven of 13 patients showed a positive patch test to “Nylon” washed in a detergent containing the brightener.