It could even be used in crime scenes
A new study has pointed out a possible connection between the scent compounds people produce and their gender, raising questions about how this might be used in forensic science. The research suggests that by analyzing the volatile organic compounds (VOCs) that come from the body, scientists can tell apart those who identify as men from those who identify as women. These VOCs, which make up a significant part of body odor, result from a combination of genetics, environmental factors, and the body’s secretions.
Last year, Kenneth Furton and his team at Florida International University conducted an experiment involving 60 participants from different ethnic backgrounds. Half of these participants self-identified as male, while the other half identified as female. For the experiment, each person was asked to hold a piece of cotton gauze in their hand and squeeze it for ten minutes. Afterward, the gauzes were left untouched for an hour before being treated with chemical reagents.
The next step involved the scientists analyzing the samples using gas chromatography and mass spectrometry. This process allowed them to identify the specific chemicals present. By applying a model based on a technique known as linear discriminant analysis, Furton’s team was able to identify the participants' self-reported genders with a remarkable accuracy of 97 percent, successfully distinguishing 29 people from each group.
John Goodpaster, from Indiana University-Purdue University Indianapolis, commented on the study, saying: "The most interesting aspect of this paper is that they were able to reliably discriminate between male and female donors through advanced statistical methods (aka chemometrics)."
However, Aaron Tarone from Texas A&M University pointed out that the study only focused on gender identification and not biological sex. He added, "A big issue here is gender versus sex. This research did not report sex of individuals, so it is unclear how correlated gender versus sex-biased odours are. This may or may not matter and likely ties to whether the odours are part of innate odour production versus gendered differences in chemical exposure to hands."
While the findings are promising, the idea of police using this information in criminal investigations is still a long way off—and not just because gender is a social construct. Hands play a crucial role in many crimes involving direct contact, such as robbery and assault, and identifying the gender of a suspect could be useful in cases where there are no fingerprints or other forms of DNA evidence.
However, it appears that the VOCs from hands don’t last long at crime scenes. Furthermore, factors like a person’s relationships, hobbies, and job may influence the chemical profiles of their hands. Goodpaster noted, "I think the main barrier to broader adoption of this method in forensic science is that hand VOCs have not been proven to linger at crime scenes or on materials, like discarded gloves or other clothing."
Despite these challenges, the study opens up an intriguing area of research that could one day contribute to forensic investigations. It may not be a practical tool for solving crimes just yet, but it certainly adds an interesting layer to how we understand scent and identity.