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40 percent of circulating coins release nickel

by Björn Schöpe

July 16, 2013 – We dedicated our first MintWorld Compendium to the aspect of health and coins. Virtually everybody handles more or less often coins (and banknotes) every day. However, as we noticed, health is not really something we consider much when we are speaking about coins. And it seems that, unfortunately, this still goes for mints.

Some recent studies revealed interesting things regarding how much nickel coins release. This is, indeed, of a certain importance to public health since 10 to 30 percent of women and 1 to 3 percent of men are affected by nickel allergy.
Between November 2011 and June 2012 the authors of a study collected 850 coins of 361 different denominations or issues coming from 52 countries covering countries in which live three quarters of the world population. They applied various nickel tests in order to analyze the amount of nickel release.
100 denominations were of a copper-nickel alloy, the most frequent alloy followed by aluminium bronze. Nearly one third (28 percent) of the denominations released nickel. Of course not all denominations are equally distributed, generally lower denominations are struck in larger quantities than coins of high face value.
However, there are only three countries whose coins are absolutely nickel-free: Bolivia, Brazil and Costa Rica. Less than 1 out of three coins or denominations from China, the Euro area, Indonesia and India release nickel. The authors estimate that about 40 percent of the circulating coin denominations do not release nickel. That sounds quite good, on the one hand.

On the other hand economically powerful countries do not ban nickel releasing coins for various motives but above all for economical ones.
Another study was dedicated to the new nickel-plated steel coins which are replacing the 5p and 10p coins. The Royal Mint stated that there was no increased risk of nickel release with these new issues after test complying with EU norms. The recent study confirms the values in general but questions seriously the suitability of this test. As the Royal Mint said after immersion of the new nickel-plated steel coins in artificial sweat for one week about half or less of the nickel was released compared to the amount of nickel released by the older cupro-nickel coins 42-190 microg/cm2.
However, as another test showed, for daily use it is much more relevant how much nickel is released during short time contact. Indeed, though increasing, the amount of nickel released is particularly high at the beginning (in the first two minutes). Six volunteers handled coins for one hour per day. While the dose of nickel conferred through skin contact ranged from 0.32 to 3.6 microg Ni/cm2 with the new cupro-nickel coins (even slightly less with older ones), the amount was significantly higher with the new nickel-plated steel coins 1.7 to 21 microg Ni/cm2.
The authors warn therefore of the increased eczema and allergy risk by using the new coins in the UK comparing their introduction with Sweden’s plans to mint completely nickel-free coins from 2015 on.

If we consider costs and security of new issues, the consumers’ health should certainly be in the focus, too. And what countries could be the first to allow economical concessions to higher production costs if not the rich industrialized countries?

You can find the article (abstract is free) on global currencies here

… and on the new UK coins here.

We reported on another study in this field last autumn in the MintWorld.

And of course you should not miss to read our first MintWorld Compendium still (for free) available as pdf file online.

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