Contact dermatitis due to printer's ink in a milk industry employee: case report and review of the allergen paraphenylenediamine.

Paraphenylenediamine is a common cause of occupational dermatoses in hairdressers, metallurgy workers, and others. Hand dermatitis developed in an employee of a milk packaging facility. The employee's hands were exposed to milk cartons embossed with wet printer's ink on a daily basis for 2 years. The worker was evaluated through a history, physical examination, and patch testing with 50 standard allergens. Patch testing revealed a positive reaction to paraphenylenediamine. The hand dermatitis resolved once the patient instituted protective measures. The worker's reaction might represent a delayed-type hypersensitivity reaction to printer's ink that contained this agent. More likely, the inciting agent was some other ingredient of the printer's ink that cross-reacts with paraphenylenediamine.