Cocoa beans naturally contain small amounts of cadmium. The typical cocoa bean contains between 0.11 and 3.32 mg of cadmium per kilogram of dry cocoa beans. This means that a 70 g serving of dark chocolate, made with 100% cocoa solids and no added sugar, would contain between 7.7 and 232.4 μg of cadmium. However, it's important to note that the amount of cadmium in cocoa beans and chocolate can vary depending on various factors, such as the soil in which the cocoa trees are grown and the processing methods used.