ABSTRACT
Allergic contact dermatitis (ACD) is an important occupational hazard, often leading to poor quality of life and signifi cant fi nancial loss for the workers it affects. Nickel allergy is one of the most common, and is highest among females and patients younger than 18 years, affecting 35.8% of patch-tested patients in North America. In contrast to Europe, where regulations have resulted in a decreasing prevalence of nickel allergy, the incidence of nickel ACD in North America is increasing (1). Denmark regulated the extent of nickel release in the ear-piercing process as well as nickel release from consumer products. In 1990 and 2006, 3881 18-69 year olds completed a postal questionnaire and were patch tested with nickel. The prevalence of concomitant nickel contact allergy and a history of hand eczema decreased among 18-to 35-year-old women from 9.0% in 1990 to 2.1% in 2006 (P < 0.01). Among older women, no signifi cant changes were observed in the association between nickel contact allergy and hand eczema. This concludes that regulatory control of nickel exposure may have reduced the effect of nickel on hand eczema in the young female population (2). From 659 items covered by the EU Nickel Directive assessed with the dimethylglyoxime test, nickel release was shown for 9% of the tested items, all of which were intended for direct and prolonged contact with the skin. A high proportion of items bought at haberdashery shops and street markets, 34% and 61%, respectively, showed nickel release. It was suggested that authorities should monitor the market regularly and give attention to areas where compliance with the requirements is poor, for protection of public health (3). Observation by relating clinical epidemiologic data with recent chemical analyses of nickel release from costume jewellery between 1994 and 2009 indicate nickel allergy decreased in men (18-30 years) and in women (1-17 and 18-30 years); however, after 2000, there was no signifi cant decrease in nickel allergy in the women aged 1-17 years. Exposure to nickel-containing products exceeding the (unnecessarily relaxed) permitted limit may explain why nickel contact allergy remains problem (4). According to part 2 of the EU Nickel Directive and the Danish nickel regulation, consumer items intended to be in direct and prolonged contact with the skin were not allowed to release more than 0.5 µg nickel/cm2/wk. It was considered unlikely that nickel allergy would disappear altogether as a proportion of individuals reacted below the level defi ned by the EU Nickel Directive. Despite this, the EU Nickel Directive part 2 was expected to work as an operational limit that would suffi ciently protect European consumers against nickel allergy and dermatitis.
