Incidence rates of occupational allergic contact dermatitis caused by metals

Data on the incidence rates (IR) of occupational dermatoses are scarce.

We calculated the IR of occupational allergic contact dermatitis (ACD) caused by chromium, nickel and cobalt by occupation, during a 7-year period (1991-1997) from the data of the Finnish Register of Occupational Diseases and from the statistics on the working population in different occupations.

A total of 2543 cases of occupational ACD were reported during 1991-1997. Cr caused 143 (5.6%) cases of ACD, Ni 176 cases (6.9%) and Co 41 cases (1.6%) of ACD. Women had greater number of occupational ACD from nickel, whereas occupational ACD from chromate and cobalt was more frequent in men. The ranking list of the IR of occupational ACD caused by Cr per 10,000 working years was (incidence rate in parenthesis) (1) tanners, fellmongers, and pelt dressers (12.20); (2) cast concrete product workers (6.94); (3) leather goods workers (4.71), (4) metal plating and coating workers (3.66); (5) bricklayers (3.44); (6) reinforcement concreters (2.79); and (7) building workers (1.32). The corresponding ranking list for Ni was (1) footwear workers (2.55); (2) machine and metal product assemblers (2.40); (3) electrical and teletechnical equipment assemblers (2.03); (4) precision instrument mechanics (1.73); (5) postal officials (1.48); (6) hairdressers, beauticians, and bath attendants (1.24); (7) industrial tailors and seamstresses (1.08); and (8) waiters in cafes and snack bars (1.04). The corresponding ranking list for Co was (1) printers (0.80); (2) turners, machinists, and toolmakers (0.36); and (3) machine and engine mechanics (0.17).

The Finnish Register of Occupational Diseases forms a good basis for calculating IR. As IR illustrates the risk to become sensitized, preventive measures should be directed at occupations with the highest IR.