Nickel release from coins

Nickel allergy is the most frequent contact allergy and is also one of the major background factors for hand eczema. The clinical significance of nick el release from coins was discussed when the composition of euro coins was decided. Current European coinage is dominated by cupro-nickel coins (Cu 75 ; Ni 25); other nickel-containing and non-nickel alloys are also used. Nick el release from used coinage from the UK, Sweden and France was determined. It was shown that nickel ions are readily available on the surface of used coins. After 2 min in artificial sweat, approximately 2 mug of nickel per coin was extracted from cupro-nickel coins. Less nickel was extracted from non-nickel coins. Nickel on the surface was mainly present as chloride. Aft er 1 week in artificial sweat approximately 30 mug/cm(2) was released from cupro-nickel coins: less nickel was released from coins made of other nicke l alloys. Theoretically, several mug of nickel salts may be transferred dai ly onto hands by intense handling of high-nickel-releasing coins.