2014-16 why we can smell coins？ steal?

That smell is your own body odor. According to a recent study, that metallic odor comes from a breakdown of oils in your skin after your touch coins and not from the coins themselves.

In the experiment for the study, researchers took gas samples from the subjects’ skins when people reported smelling the metallic odor after touching iron. The smell was then traced to 1-octen-2-one which is an organic molecule formed when certain oils in skin decompose. The researchers believe that when a person touches an object made of iron, the perspiration from their skin causes the iron atoms to gain two electrons. These iron atoms then react with oil in skin forming 1-octen-2-one.

研究人员对从测试物体的表面收集的气体样本进行测试，发现了一些具有“金属气味”特征的不同的有机化合物。这种气味的主要成分被称作1-octen-2-one，即使在高度稀释的情况下，它也能发出与霉味一样的金属味道。这种气味分子的前体是脂肪过氧化物，当皮肤上的油脂被某些酶或通过其他方法(例如，在紫外线照射下)氧化时，就会产生脂肪过氧化物。随后这些脂肪过氧化物又被双重金属负离子分解，从而产生三重金属负离子。当接触铁质物体时，皮肤排的汗液腐蚀金属，从而形成必要的双重金属负离子。