The suspicious wife sniffing her husband for the scent of another woman’s perfume on his shirt: it’s an old Hollywood cliché, but it’s got forensic science behind it.
That’s according to a group of scientists in London, who have discovered that a fragrance’s chemical components can easily transfer from one person’s clothing to another – and linger there for days.
But rather than using their discovery to sniff out adultery, the team say that this research could help detectives solve violent crimes, including sexual assaults.
The results of the study suggest that perfumes have the potential to be used as “trace evidence”: the tiny pieces of forensic evidence, such as hair, soil or flecks of blood, which are often left behind at the scene of a physical crime.
“We thought there was a lot of potential with perfume because a lot of people use it,” says lead researcher Simona Gherghel, from University College London. “We know about 90% of women and 60% of men use perfume on a regular basis.”
She adds that while lots of forensic research has been done on other kinds of “transfers – for example, the transfer of fibres or the transfer of gun-shot residue” – this is the first piece of research into the transfer of perfumes.
A crucial part of the study involved the scientists pinpointing when fragrances were transferred from one piece of fabric to another, meaning that detectives may later be able to link criminals to the time of the crime as well as the scene.
“We’ve shown that first, perfume does transfer, and second, we can identify when that transfer has happened,” says Dr Ruth Morgan, director of the UCL Centre for the Forensic Sciences.
“In the future there could well be situations where contact between two individuals is made and this is a way of discerning what kind of contact is made and when it was made.”
However, the team stressed that more research needs to be done before fragrance will be used in forensic investigations – adding that perfume is unlikely to make or break a criminal investigation.
“It is not going to be a one-stop indicator,” says Dr Morgan. “In most investigations we would be hopeful that there would be multiple lines of investigation. We wouldn’t want it to just be DNA or just a fingerprint or just perfume.
“But in combination, with other forms of evidence, that’s the way it builds up into a very compelling picture.”