Occupational contact dermatitis due to nickel allergy.

Contact allergy to nickel is a large dermatological problem affecting 10-15% of women and 1% of men in the general population. The aim of this study was to illustrate the significance of occupational nickel exposure in men. Patch testing was carried out to identify patients with nickel allergy and the dimethylglyoxime test was used to identify sources of nickel exposure. 8% of the men and 30% of the women were patch-test positive to nickel. Most of the patients had hand eczema, and a few had facial eczema. Tools and equipment used in different jobs by workers such as carpenters, electricians, painters, and plumbers were often found to cause nickel release. Black-nickel plating is used for optical equipment while cold-sealing of aluminium with nickel is a method of treating anodized aluminium. Both black-nickel and cold-sealed aluminium were found to be unexpected causes of dermatitis due to nickel release. Sources of occupational nickel exposure are often missed by dermatologists, due to lack of knowledge. Occupational nickel exposure is however important to identify, and the dimethylglyoxime test is a helpful tool.