The metal composition of euro coins was decided by a Council regulation in 1998. Nickel was already widely used in national coins in Europe, including Irish coins. It is also used in coins in many other countries throughout the world including for example the five cent coin in the United States.
There is now far less nickel in coins in circulation than was the case before the euro was introduced. Nickel is used in only two of the euro coins – the €1 and €2 coins. By contrast, nickel was used in the 5p, 10p, 20p, 50p and £1 coins of Irish currency. This pattern is replicated throughout the euro area. As a result 85% of euro coins, in terms of the number of coins in circulation, are nickel-free as opposed to 25% of the national coins that they replaced.
I am also informed by the Central Bank that since the introduction of euro coins into circulation, they have received no reports of nickel allergy problems arising from the coins.