I was cleaning up a concentrated formic acid spill and when I was close enough to the hood to get a whiff it smelled exactly like the smell sensation from hitting my head.

We know that olfactory memory is very keen. While many people identify a vaguely metallic odor when hit in the head, I doubt many non-chemists have had occasion to smell pure formic acid. Do chemists familiar with the chemical generally agree that formic acid matches the olfactory sensation of head concussion?

If so: Is there a physiological effect of head concussion that would mimic the effects of formic acid vapor on the olfactory system? (Or maybe even produce formic acid that could be picked up by olfactory nerves?)

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    $\begingroup$ I'm voting to close this question as off-topic because it is more about the biological process, hence should be on biology. $\endgroup$
    – Jan
    Aug 20, 2016 at 15:20
  • $\begingroup$ I edited to make it clear that this is a general question, not a personal question. And note that most of the smell questions implicate the "biology" of olfaction. But, when they're answered, such Q&As can be both very popular and highly rated. $\endgroup$
    – feetwet
    Aug 21, 2016 at 13:46
  • $\begingroup$ I've both (a) smelled pure formic acid and (b) experienced head trauma. I've never noted a link between (a) and (b). The only inkling I have ever heard that the two might be related is your question. My (off-topic) guess is that your association of the two is purely idiosyncratic. $\endgroup$
    – Curt F.
    Aug 22, 2016 at 6:52
  • $\begingroup$ @CurtF. - That's a useful data point. I don't suppose, in the interest of science, we could get a bunch of chemists to hit their heads against a hard object? Or, perhaps more practically, get a bunch of chemists to visit soccer practice fields with a vial of formic acid and ask players if the smell reminds them of anything? (Note that this depends not only on the severity of the blow – e.g., it can't be so severe as to render the observer incapable of noting the immediate smell sensation – but may also depend on the direction of the blow – see, e.g., nasal impingement of the cribiform plate.) $\endgroup$
    – feetwet
    Aug 22, 2016 at 14:03
  • $\begingroup$ I've noticed that smell with isopropyl alcohol, but not every the time. It could be some additive or impurity used when it's sold as a cleaning product for electronics, or a reaction with what it's cleaning, or it could be the strength of exposure. Maybe it's just the synaesthesic smell of brain damage? $\endgroup$
    – sh1
    Oct 29, 2016 at 21:40


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