Yesterday, I discussed octenol, a lipid degradation product that's all over your skin. Ever wonder why a cut on your hand smells "like metal," or your hands smell "like metal" after handling some?
Metal ions are great at shuttling electrons around, and that's just what they're doing here. The iron ions in blood (or metal oxides on the metal surface) catalyze the oxidation of the same lipids that degrade to octenol to something a little more oxidized (that is, octenone) - the oxidizing equivalents just come from the air. Octenone is where that metal smell comes from!
Of course, you need skin lipids to get the octenone smell. If you've ever bled a lot (and you have a rigorous scientific disposition, giving you sufficient presence of mind to note the odor), you might have noticed that there was not much smell. A paper cut or nosebleed (or the scabs on your knees you used to pick off as a kid), however, has gobs of octenone aroma. This is because the blood needs to hang out on the surface of the skin to do the catalysis.
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There's a novel - Rancid Aluminium - which evokes this curious notion of smelly metal. Anyone who plays guitar and hasn't changed their strings for a while will also know about smelly metal. I wrote about metallic BO and the scent of blood for SpectroscopynNOW a while back, which all ties in with your post.
Neat. rb
Today the basement smells like metal. (reminds of the smell you get from a stainless steel pot if you scrub it)
this is a new smell since today. previously it just smelled musty. the house is old and the basement is only partially under the ground. the smell starts as you come down the stairs. What could this be? It's very obvious that the air has changed... but why?
what might cause the air to smell like metal?