Nickel Sensitization: Impact Of The European Union Nickel Directives

Introduction: Nickel is a widely used metal and contact allergen. It can be found in our everyday objects and it is becoming more prevalent in healthcare. Simultaneously, nickel contact sensitization occurs more frequently.Objective: Analysis of data of patch tested patients by gender, age, diagnosis, localization of skin lesions, and associated metal sensitivity. Furthermore, to study the effects of the European Nickel Directives in force since 2004.Method: Retrospective analysis of data of 13 693 patients (aged 10-87) tested with a standard series of contact allergens at the Allergy Outpatient Unit and Laboratory of the Department, Venereology and Dermatooncology, Semmelweis University.Result: Nickel sensitization of all examined patients was 13.1% in 1994, 11.5% in 2004, and 19.1% in 2014. Contact dermatitis occurred mainly in females (93.0%). Skin lesions are primarily localized to the arms and face. Diagnosis of allergic contact dermatitis occurred in 65.8%, and atopic dermatitis in 9.7% of tested patients. Commonly associated metal sensitivities were cobalt and chromium. In the 10 years following the Nickel Directives, the increase of the ratio of sensitized patients was significant while the number of nickel-positives per year decreased. Both in 1994 and 2004, the largest proportion of patients belonged to the 20-24 age group (26.5% and 20.8%, respectively), but in 2014, to the 35-39 age group (15.1%).Conclusion: Nickel sensitization shifts towards the older age group, with a decrease in young patients. Because of the Nickel Directives, people are exposed to nickel at a later age and to a lesser extent. Due to the increase of the ratio of nickel-sensitive patients, it is necessary to introduce new regulations and amend the existing ones.