MIAMI — The scent of a person’s hand can reveal their sex, potentially aiding in criminal investigations, according to new research. Scientists in Florida have found they can predict a person’s biological sex with over 96 percent accuracy based solely on the smell of their hand.
Dogs have been used in criminal investigations for years to identify and track people based on their odor. However, while human scent evidence is well established in the field, researchers have made limited progress in analyzing human scent profiles in the laboratory.
In this recent study, researchers used a technique called mass spectrometry to analyze the scent of the palms of 60 individuals, half of whom were men and the other half women. After identifying the compounds in each sample, the team determined if they could deduce the individual’s gender based on their scent profile. The team successfully predicted a person’s sex with near-perfect accuracy rate using this method.
Scroll down to see 7 applications of mass spectrometry
Previous research has also indicated that the scent of a hand can provide information about a person’s age and racial or ethnic group. By employing these techniques, crimes such as robberies, assaults, and rape cases — which often involve the perpetrator’s hands — could be easier to solve.
“This approach to analyzing hand odor volatiles can be applied when other discriminatory evidence such as DNA is lacking and allow for differentiation or class characterization such as sex, race, and age,” says Dr. Kenneth Furton, executive director of the Global Forensic and Justice Center and chief scientific officer of Florida International University, in a media release.
Mass spectrometry is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are typically presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used in many different fields and is applied to pure samples as well as complex mixtures.
The technique works by ionizing chemical compounds to generate charged molecules or molecule fragments and measuring their mass-to-charge ratios. The ionized molecules or fragments are then separated according to their mass in the mass spectrometer. The basic components of a mass spectrometer are the ion source, the mass analyzer, and the detector. The ionizer converts a portion of the sample into ions. The mass analyzer separates the ions according to their mass-to-charge ratio, and the detector measures the value and abundance of the separated ions.
The technique has both qualitative and quantitative uses. For instance, it can be used to identify unknown compounds via their mass spectrum, to quantify known compounds, and to determine the structure and chemical properties of molecules.
Mass spectrometry has many applications in various fields such as:
- Chemistry: To determine the composition and structure of a compound.
- Pharmacokinetics: To study the fate of substances within the body.
- Space exploration: To study the composition of planets and moons.
- Proteomics: To identify proteins and analyze their structure.
- Environmental studies: To identify contaminants in water and soil.
- Forensics: To identify substances found at crime scenes.
- Geology and archeology: To date artifacts and to trace the origin of rocks.
The versatility of mass spectrometry makes it a valuable tool in scientific research and industry. However, using it requires specialized knowledge, as interpretation of the results can be complex.
The study is published in the journal PLoS ONE.
South West News Service writer Alice Clifford contributed to this report.