About 20% of the female population in Europe have been sensitised to nickel, mainly from wearing cheap jewellery. Sensitisation causes the skin to become itchy and sore when it comes into contact with items containing nickel. Due to the scale of the sensitisation problem, the European Union introduced a directive restricting the use of nickel in items intended to come into contact with the skin. Items that release sufficient nickel to cause sensitisation are banned from sale.
To identify items that contain nickel, a simple spot test has been developed. Items that give a positive result with the spot test are submitted for further testing to measure accurately the amount of nickel released. 'Testing for nickel on the spot' describes the test and the background to the nickel sensitisation issue.