Occupational allergic contact dermatitis due to a black rubber pencil grip

Para-phenylenediamine (PPD) is a well known vulcanizing agent of black rubber. Objects containing black rubber are often the cause of occupational allergic contact dermatitis. Repeated daily contact with articles containing PPD at low concentration can be equivalent to a single higher-dose exposure to PPD and may cause allergic contact dermatitis in sensitized patients. A case of a 26-year-old office worker in a furniture store, affected by allergic contact dermatitis which was caused by a black rubber pencil grip is reported. The patient was sensitized to PPD. Chemical analyses demonstrated that small quantities of PPD degradation products were present in the patient's rubber pencil grip.