Nickel coinage in the United States: the history of a common contact allergen.

Abstract

Nickel is the most common contact allergen found in patch testing.1 The diagnosis of nickel allergy is usually straightforward: the skin becomes scaly and eczematous after contact with metal suspenders, metal buttons or clasps (figure 1), medical alert pendants (figure 2), or ear-rings. Because of the nickel content in coins, the change in a patient's pockets can cause an allergic skin reaction. In this article, we discuss the history of nickel as a 3- and 5-cent piece and as the base metal used in most of the coins currently in circulation (figure 3). Open in a separate window Figure 1 Eczematous plaque on the abdomen of a young boy caused by contact with a metal button on his pants and his belt buckle