Scientists Isolate Body Odor's Specific Smells One Volatile Compound at a Time

Since the proliferation of washing machines, we’ve masked body odor by blasting smelly clothes with hot water and detergents. But, as water becomes a more valuable resource, people are being forced to admit that washing clothes was a stopgap solution. In order to stop ourselves from smelling over the long term, we’re going to have to figure out why and how we smell in the first place. The technology that replaces the washing machine will be built off this knowledge.

On Wednesday the Journal of Chromatography A published a paper by researchers who have begun to the crack the case of our musk. Northumbria University scientists identified six volatile compounds in dirty clothes pre and post-wash — chemical compounds that are particularly, unpleasantly pungent. These six VOCs are: butyric acid, dimethyl disulfide, dimethyl trisulfide, 2-heptanone, 2-nonanone, and 2-octanone. Together, you get a rancid banana-butter-floral-onion mess.

“The need to conserve the environment by reducing the wash temperature and the use of biodegradable washing products have grown in importance in the millennium, making this type of research more high profile,” co-author Professor John Dean told Phys.org.

To identify these chemicals, which Dean believes could be used to test the effectiveness of washing at lower temperatures, the team conducted two experiments. In the first, six women and two men were asked to wash their feet with tap water, put on a pair of new socks, then wear them around in shoes for 10 hours. The second experiment involved nine men who wore a t-shirt for two to three hours while playing soccer. In each case, the subject’s clothing items were taken, bagged separately, and stored overnight.

The team then used a process of analysis on the clothes known as SHS-MCC-GC-IMS before they were washed, when they were wet after washing, and once dried. This mouthful of an acronym is short for a series of experiments: Static headspace, multicapillary column, gas chromatography, ion mobility spectrometry. The sensory evaluation, which is known for being speedy and specifically helpful in identifying sulfur-based compounds, allowed the researchers to identify the specific six volatile compounds that emerge through the process of malodor formation.

By isolating these specific odors, scientists have give us the ability to better articulate the specific ways in which other people are disgusting to us (“Frank smells like rotting fruit because of his butyric acid problem”), but no clear way to solve the problem. The issue remains that odors are intensely complicated. They arise from the compounds, sure, but also from the way compounds and bacteria react to heat and sweat and the presence of substances secreted by human glands. Body odor is a cocktail and the ability to name some of the ingredients does not a recipe, much less a chaser, make.

While human pheromones have yet to be identified, we do know that our odors communicate information about genetic quality — meaning that the right smell can help you hook up. So take comfort in the fact that while scientists try to figure out how to help us not stink, we can take advantage of funky pits to find a mate.