Have you ever wondered why coins have a musty, metallic odor after they have been in your hands awhile? You may have assumed that it was the coins being dirty, but in reality it isn’t the coins at all – it’s you. That’s right. 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.

Hat tip: LiveScience.com