By Tom Avril The Philadelphia Inquirer
PHILADELPHIA — And now, from the department of vital information that it never occurred to you to think about, we bring you earwax odor.
Scientists at the Monell Chemical Senses Center report that compared to whites, the earwax of east Asian people contains significantly lower amounts of odor-causing substances called volatile organic compounds.
Setting aside for a moment the tale of how this odd topic became the focus of study, it turns out that the fragrance of one’s auditory canal could have medical implications.
George Preti, an organic chemist at the research institute in West Philadelphia, said earwax odor already can be used as a quick diagnostic tool for certain rare metabolic diseases. And he is optimistic that the earwax of a cancer patient might also contain some telltale fragrance, which could be detected by trained dogs.
Scientists have known for decades that the earwax of east Asians is dry and whitish, whereas that of others is moist and yellowish-brown.
More recently, researchers have traced this difference to a genetic mutation, and they have found that the very same mutation causes east Asians to have much less underarm odor. Go figure.
So Preti wondered: If the appearance of earwax was linked to underarm odor, what about the odor of the earwax itself?
He enlisted Monell postdoctoral fellow Katharine Prokop-Prigge to help him tackle the question, and the results were published online in the Journal of Chromatography B.
The researchers sampled earwax, also called cerumen, from 16 study participants, eight of them east Asian and eight Caucasian. Chemical analysis revealed higher amounts of seven volatile organics in the Caucasian earwax.
Just one compound turned up in higher amounts in the Asians — a chemical that is contained in chili peppers, leading Preti to surmise that there might be a connection between earwax and diet.
Preti and two other judges also put earwax to the sniff test, finding the odors from the two ethnic groups to be fairly similar.
Preti acknowledges that lay people may find earwax to be a weird target for study. He even gets amused reactions when he enlists physicians to collect the substance from their patients.
“I get a lot of yuks, and they say, ‘Suuure,’” Preti said. “I have to stay on them.”
Weird or no, the substance plays an important role, helping to lubricate the ear canal and filter out debris.
Preti also thinks earwax could be a tool beyond the medical realm. He cited a study last year in which Baylor University scientists identified environmental contaminants in the earwax of a blue whale, providing a record of the waters in which it had swum.
He proposed that similar methods might help police tell if a person has been in a given city by whether his earwax contains its telltale pollutants.
“From a forensic standpoint, it could be very interesting, telling people where you’ve been and how long ago you’ve been there,” Preti said.