Determination of allergy-causing metals from coins

Abstract  The majority of everyday items contain metals and their alloys, although many of them may be harmful to human health. Nickel, originating from different sources such as coins, jewelry, or buttons, represents the most common cause of contact allergy dermatitis. Therefore, the aim of this research work was to estimate the possible risk of allergy resulting from skin exposure to coins. In order to obtain information on the amounts of metals released by their daily use, extraction experiments of coins were performed applying an artificial acidic sweat solution during varying extraction periods. After extraction, the mass of the metals released (copper, iron, nickel, and zinc) were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). The mass rate of Ni extracted per area considerably exceeded the permissible values according to the European norm: 50 times for 50-lipa coins, 80 times for 20-lipa coins, and 110 times for 1-kuna coins. This indicates that nickel-containing coins may represent a serious health hazard, especially to sensitive people. Graphical abstract