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Positive patch tests to Euro coins in nickel-sensitized patients
E Nucera1, D Schiavino, A Calandrelli
1Department of Allergology, Università Cattolica del Sacro Cuore, Policlinico A.Gemelli, Largo A.Gemelli 8, 00168 Rome, Italy.
Background:
Many efforts have been made to prevent nickel allergy, the most frequent contact allergy in industrialized countries, by identifying acceptable limits of exposure. Even though coins are not covered by the EU Nickel Directive, some authors suggest that nickel release from coins during handling may elicit contact dermatitis in nickel-allergic people.
Objectives:
To evaluate sensitivity to nickel released from coins in nickel-allergic patients and to verify whether nickel release from the new Euro coins may elicit stronger cutaneous reactivity than from old Italian lire coins.
Methods:
Twenty-five nickel-allergic patients were patch tested with 1- and 2-Euro coins, 1-, 2- and 50-Euro cent coins, and 100 and 500 Italian lire coins. Ten healthy nonnickel-allergic control individuals were also tested.
Results:
Nineteen patients had positive patch tests to 1- and 2-Euro coins. One was also positive to 1- and 2-Euro cent coins, four to 50-Euro cent coins, and 13 to the 500-lire coin. None had a positive patch test to the 100-lire coin. The number and degree of positive patch tests to coins were related to nickel content.
Conclusions:
Euro coins may be potentially more dangerous than old Italian coins. Coins containing little or no nickel should be chosen for coinage to prevent sensitization and to avoid exacerbation of contact dermatitis in nickel-allergic patients.
