Holding on to your cash might be good for your finances but not for your skin–at least in Europe.
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A new study concludes that 1-euro and 2-euro coins release up to 320 times as much nickel as European standards permit for prolonged contact with the metal, a common skin allergen.
The culprit is the coins’ two-toned structure, the researchers report. Unlike other euro coins, the 1-euro and 2-euro pieces contain a ring of one nickel-containing alloy surrounding a center made from a different nickel alloy. Euro coins began circulating in 12 European countries in January.