Nickel allergy following European Union regulation in Denmark, Germany, Italy and the U.K.

BackgroundNickel allergy is common worldwide. It is associated with hand dermatitis, and sensitization is often induced by nickel-releasing jewellery. The European Union (EU) introduced legislation to control nickel content and release from jewellery and other consumer items through the EU Nickel Directive 1994, which came into force in 2001 and is now part of the REACH regulation. ObjectivesTo examine the effects of the EU nickel regulations on the prevalence of nickel allergy in four European countries. MethodsNickel patch-test data from 180390 patients were collected from national databases in Denmark, Germany, Italy and the U.K. from between 1985 and 2002 to 2010. Patients with suspected allergic contact dermatitis who had been patch tested with nickel sulfate 5% in petrolatum were included in the analysis. The main outcomes studied were the percentage of positive results to nickel patch tests, and changes in trends with time in an age- and sex-stratified analysis. ResultsA statistically significant decrease in nickel allergy was observed in Danish, German and Italian women aged below 30years. In female patients in the U.K. this was observed between 2004 and 2010. In young men, a statistically significant decrease in nickel allergy was observed in Germany and the U.K., whereas a nonsignificant increase was observed in Italy. ConclusionsThere has been a reduction in the prevalence of nickel allergy in young women, contemporaneous with the introduction of the nickel regulation. A reduction is also suggested in men in Germany and the U.K. A causative effect of the regulatory intervention is the most likely explanation.