Allergic contact dermatitis to crystal violet in carbonless copy paper.

The article presents a case in which the patient, an office clerk got an irritant vesicular rash on the palms which spread to the back and sides of her fingers. Her work entailed day-long handling of significant quantities of Carbonless copy paper and carbon paper and operating a visual display unit. Initial patch tests to a standard battery and to carbonless copy paper gave positive allergic reactions to nickel sulphate 5%, cobalt chloride 1% and fragrance mix 8%, but no reaction to the paper handled. Further tests indicated an allergic reaction to crystal violet lactone present in the carbonless copy paper.