title: Provocative use test of nickel coins in nickel-sensitized subjects and controls.
abstract: BACKGROUND
  Consensus exists on levels of nickel release that are well tolerated in exposure to nickel-containing items in direct and continuous contact with skin (e.g. watches). The clinical relevance of nickel-containing coins eliciting nickel dermatitis associated with extensive occupational exposure (e.g. coins handled by cashiers) has not been determined.
  
  
  OBJECTIVE
  To examine whether nickel-containing coins might be an elicitor of allergic contact dermatitis (ACD) in occupational settings with extensive exposure to coins (i.e. cashiers).
  
  
  METHODS
  Eighteen subjects (10 nickel sensitized and eight non-nickel sensitized) completed this study after screening of history, physical examination and diagnostic patch testing (5% nickel sulphate). Each volunteer handled 10 coins (nickel-containing coins or non-nickel-containing coins) in a cross-over design at 5-min intervals (5 min handling followed by 5 min rest) for 8 h per day, for a total of 12 days excluding the weekend. One hand was gloved while the other was not during coin handling. Visual scoring and bioengineering measurements were recorded at each of four predetermined sites at baseline (day 1), end of day 5 and day 12 (last day of exposure).
  
  
  RESULTS
  There were no statistical differences for either visual or bioengineering data comparing: (i) nickel-sensitized vs. non-nickel-sensitized subjects handling nickel-containing coins at day 1, day 5 and day 12; (ii) day 12 vs. day 1 (baseline) for nickel-sensitized subjects handling nickel-containing coins; (iii) handling of nickel-containing coins vs. non-nickel-containing coins by nickel-sensitized subjects at day 5 and day 12; (iv) gloved hand vs. ungloved hand of nickel-sensitized subjects handling nickel-containing coins at day 12. Limitations of the method and clinical extrapolation are detailed.
  
  
  CONCLUSIONS
  Individuals handling these nickel-containing coins daily did not develop ACD, as judged by visual signs or bioengineering parameters.
authors.affiliation: Department of Dermatology, University of California, School of Medicine, Surge 110, Box 0989, San Francisco, CA 94143-0989, USA.
authors.forename: H
authors.initials: H
authors.lastname: Zhai
authors.forename: A-L
authors.initials: AL
authors.lastname: Chew
authors.forename: S J
authors.initials: SJ
authors.lastname: Bashir
authors.forename: K E
authors.initials: KE
authors.lastname: Reagan
authors.forename: J J
authors.initials: JJ
authors.lastname: Hostynek
authors.forename: H I
authors.initials: HI
authors.lastname: Maibach
mesh_terms: D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D017449:Dermatitis, Allergic Contact / Q000209:etiology*; D009783:Dermatitis, Occupational / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009532:Nickel / Q000009:adverse effects*; D009717:Numismatics; D016273:Occupational Exposure; D010328:Patch Tests; D014870:Water Loss, Insensible / Q000187:drug effects
chemical_list: D009532:Nickel