Frequency, spectrum and occupational relevance of type IV allergies to rubber chemicals

3851 consecutive patients patch tested between January 1985 and March 1990 have been analysed for rubber allergies. The incidence of rubber allergy was 3.8% (n = 145). In 80/145 patients (55%), the source of rubber sensitization was occupational, 67 of whom (84%) had acquired allergy from wearing rubber gloves at work. Most of them (36%) were employed in the health services. The most commonly positive rubber-mix in this group was thiuram-mix (72%) followed by carba-mix (25%). 13/80 patients (16%) had occupational rubber allergy from industrial rubber products other than gloves. Patch tests revealed thiuram-mix (62%) as the most commonly positive rubber-mix but, in contrast to the group with glove-induced rubber allergy, black-rubber-mix came second (38%). In 47/145 patients (32%), the source of rubber sensitization was non-occupational; in 18/145 (13%) the origin remained unknown.