Research finds sex can be confirmed by hand odor

FIU researchers determined a person’s biological sex can be confirmed by their hand odor with extreme accuracy.

The novel approach can assist in forensic investigations when other biometric indicators, such as DNA and fingerprints, are limited or non-existent. The study was published in PLOS ONE, an open access science journal.

“Our research at FIU is always focused on moving the forensic sciences forward,” said Kenneth G. Furton, executive director of the Global Forensic and Justice Center (GFJC) and the project’s administrator. GFJC has one of America’s oldest forensic science education programs and has grown into one of the world’s largest forensic science centers, as well as among the most diverse in terms of areas of study, degree areas and geographical reach. “A focus of GFJCis to work on research that can be used right now in laboratories to help science serve justice effectively and efficiently.”

According to FBI figures, about 72% of crimes are committed by men and about 28% by women. The research also could lead to non-forensic applications in the future.

The current study relies on a foundational principle in forensic science – every contact leaves a trace. When a suspect touches something, they leave something behind, including their odor.

The research team collected samples from 60 volunteers, evenly divided among men and women, using sterile gauze pads to capture their hand odor. Using instruments commonly found in forensic toxicology and chemistry laboratories, such as gas chromatrography/mass spectrometry, combined with an innovative sampling method and a data analysis program developed by FIU chemistry Ph.D. graduate Vidia Gokool, the team analyzed the volatile organic compounds (VOCs) responsible for an individual’s odor. The person’s sex could be determined accurately more than 96% of the time using a human-supervised machine learning model.

While canines can identify human scent, living or deceased, this is one of the first times a person’s odor has been analyzed in the laboratory to accurately determine sex.

“This technique could be used in conjunction with detection canines,” said Chantrell Frazier, lead researcher. “It can be one more tool for investigators to use to bring justice to victims of crime.”