Contact allergic dermatitis to dicyclohexylcarbodiimide used in protein synthesis

Dicyclohexylcarbodiimide is a commonly used coupling agent found in protein synthesis. It is a potent allergic sensitizer found especially in the emerging industries involved in recombinant DNA synthesis. Chemists who work in research and development of this industry are especially at risk of development of contact dermatitis, unless they are careful and avoid skin contact. This report describes two chemists with allergic contact dermatitis from repeated contact with this compound in their work as research and development chemists. An appropriate concentration for patch testing is suggested.