Colophony (rosin) in newspapers may contribute to hand eczema.

Two groups of patients were studied, one with known contact allergy to colophony and hand eczema, 'colophony patients', and the other consisted of patients who suspected that their eczema was caused by contact with paper, 'paper patients'. The 'colophony patients' were patch tested with samples of newsprint paper, while the 'paper patients' were tested with samples of their own paper. Extracts of the paper and paper were applied. Testing with paper caused no reactions. All 'colophony patients' showed strong reactions to the tested extracts of newsprint paper. None of the 'paper patients' reacted to the extracts of their own paper, except those patch-test positive to colophony or maleopimaric acid, the main component of one type of modified colophony in paper size and shown experimentally to be a potent sensitizer. Colophony in paper may contribute to hand eczema in sensitized patients and the use of cotton gloves when in contact with paper might alleviate the dermatitis.