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5:03 am
Thu March 20, 2014

Digging For Gold: Study Says Your Race Determines Your Earwax Scent

Originally published on Thu March 20, 2014 6:40 am

I'm not sure what type of situation would lead you to compare your earwax with anybody else's earwax. (Because, gross.) But researchers at the Monell Chemical Senses Center have found that the smell of ear gold varies by race. The volatile organic compounds in earwax — call it cerumen, if you're in a scientific mood — can contain key information about your body and your environment.

So Why Did The Researchers Start Digging?

The head researcher, George Preti, has been looking into animal and human body odors for more than 40 years. He tells me he's had a "long-standing interest" in underarm odor. Preti came across an article from Japanese researchers that examined the scents of East Asians and people of European backgrounds, and he says it linked earwax to underarm odor.

"I was curious about what odors are being produced in the ear and how similar or different they are to underarm odor. We already had a pretty good inkling that underarm odor is different in most East Asians than [people of] European or African descent," Preti says.

Finding Gold

Preti says that regardless of race, we all produce the same odors — just in different amounts. For instance: White men have more volatile organic compounds in their earwax than Asian men.

The researchers compared samples from East Asian and Caucasian men. (They're planning on sampling women — whose scents change during menstrual cycles — in the future, and don't think the results will change.)

If you're East Asian, for example, the scents of your earwax and underarms are most likely different from those of non-Asians. The earwax from the study's East Asian donors was "consistently drier and colorless." The samples of the white donors were "yellow and sticky in nature."

Also mentioned in the study: "Africans" have "wet, yellowish-brown wax," and Native Americans — similar to East Asian folks — typically have "dry, white wax."

"The difference between [the earwax] is caused by a single gene in the genome. And a change in that single gene gives you different earwax and different underarm odor," Preti explains.

What Does It All Mean?

In another study, a set of different researchers ran a chemical analysis on the earwax plug of a blue whale that had been struck by a boat. Since whales don't have hands or Q-tips to clean their ears out with, Preti says, the wax accumulated.

"[The wax] gave a life history of the whale, much like tree rings tell you things about the life of a tree — when it grew or didn't grow," Preti explains. The scientists were able to figure out the whale's life history — where it had been, what was in the water with it, when it went through hormonal changes during puberty, when it was sexually mature — through the different molecules that got stuck in the earwax.

So what, besides one's ethnicity, can earwax tell us about people? Preti says this is their next big question.

Earwax can be a pretty valuable source of information, according to these researchers. Molecules get trapped in the sticky, waxy goo, holding clues about a person's life. But since people tend to clean their ears (because, again, gross), it's not clear how long information can be retained in the wax — a couple of hours, a couple of months.

"We like to think it's going to be an exciting, novel area for environmental information as well as disease metabolites which may accumulate in the earwax — we're going to see what we can find," Preti says.

One of the burning questions I had for Preti after learning about the research was: Does earwax really have a scent that's strong enough for me, a mere human, to notice sans equipment?

"If you take a Q-tip and roll it around in your ear and stick it around in your nose," Preti tells me, "I think you'd be able to smell it. Give it a try."


Quiz answers: A) "acidic/pungent"; B) "fecal"; and F) "sweaty feet."

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