The Sino-American belt study: nickel and cobalt exposure, epidemiology, and clinical considerations.

Background: Nickel and cobalt are common causes of metal allergy.

Objective: The objective of this study was to investigate nickel and cobalt exposure in belt buckles by testing 701 belts purchased in China and the United States and to consider the prevalence of nickel allergy and its relevance among Chinese patients.

Methods: Seven hundred one belt buckles purchased in China and the United States were tested for nickel and cobalt release.