title: Cobalt release from inexpensive jewellery: has the use of cobalt replaced nickel following regulatory intervention?
abstract: BACKGROUND
  Before the introduction of the EU Nickel Directive, concern was raised that manufacturers of jewellery might turn from the use of nickel to cobalt following the regulatory intervention on nickel exposure.
  
  
  OBJECTIVE
  The aim was to study 354 consumer items using the cobalt spot test. Cobalt release was assessed to obtain a risk estimate of cobalt allergy and dermatitis in consumers who would wear the jewellery.
  
  
  METHODS
  The cobalt spot test was used to assess cobalt release from all items. Microstructural characterization was made using scanning electron microscope (SEM) and energy-dispersive spectroscopy (EDS).
  
  
  RESULTS
  Cobalt release was found in 4 (1.1%) of 354 items. All these had a dark appearance. SEM/EDS was performed on the four dark appearing items which showed tin-cobalt plating on these.
  
  
  CONCLUSIONS
  This study showed that only a minority of inexpensive jewellery purchased in Denmark released cobalt when analysed with the cobalt spot test. As fashion trends fluctuate and we found cobalt release from dark appearing jewellery, cobalt release from consumer items should be monitored in the future. Industries may not be fully aware of the potential cobalt allergy problem.
authors.affiliation: National Allergy Research Centre, Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, University of Copenhagen, DK-2900 Hellerup, Denmark. jacpth01@geh.regionh.dk
authors.forename: Jacob Pontoppidan
authors.initials: JP
authors.lastname: Thyssen
authors.forename: Morten S
authors.initials: MS
authors.lastname: Jellesen
authors.forename: Torkil
authors.initials: T
authors.lastname: Menné
authors.forename: Carola
authors.initials: C
authors.lastname: Lidén
authors.forename: Anneli
authors.initials: A
authors.lastname: Julander
authors.forename: Per
authors.initials: P
authors.lastname: Møller
authors.forename: Jeanne Duus
authors.initials: JD
authors.lastname: Johansen
mesh_terms: D003035:Cobalt / Q000032:analysis* / Q000633:toxicity; D003718:Denmark; D017449:Dermatitis, Allergic Contact / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D055498:Jewelry / Q000009:adverse effects* / Q000032:analysis*; D009532:Nickel / Q000032:analysis / Q000633:toxicity
chemical_list: D003035:Cobalt; D009532:Nickel