Science

Novel forensic technique identifies people by their hair

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Prof. Diane Beauchemin analyzes hair in her lab (Photo: Anne Craig)
Prof. Diane Beauchemin analyzes hair in her lab (Photo: Anne Craig)
Lily Huang grinds hair samples for analysis (Photo: Anne Craig)

If you watch any cop shows, then you know that a person's race and gender can be determined by doing a DNA analysis of one of their hairs. Now, however, Canadian scientists at Queen's University have developed a method of obtaining that same information from hair samples, that's quicker than DNA testing and is 100 percent accurate.

The system was created by chemist Prof. Diane Beauchemin and student Lily Huang.

It involves washing and drying a hair sample, grinding it into a powder, burning that powder, then using "solid sampling electrothermal vaporisation inductively coupled plasma optical emission spectrometry with multivariate analysis" (phew) to analyze the vapor. Doing so allows investigators to identify sweat secretion-derived elements in the hair, that vary according to factors such as diet, ethnicity, gender, environment and working conditions.

Lily Huang grinds hair samples for analysis (Photo: Anne Craig)

The whole process takes just 85 seconds. That's considerably shorter than DNA analysis, which involves the use of reagents and solvents. In lab tests, it accurately identified 13 hair samples as coming from people of East Asian, Caucasian or South Asian backgrounds, along with their gender.

Although forensic scientists also commonly get such information from blood samples left at crime scenes, blood can quickly deteriorate or become contaminated, whereas hair is much more stable.

Beauchemin now plans on refining the technique to identify a wider range of ethnicities, along with the subject's specific age. A paper on the research was recently published in the journal Chemistry World.

Source: Queen's University

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11 comments
Wombat56
So does it just detect ethnicity or can it come closer to defining individuals?
I'd have thought the myriad of different metabolites of varying diets and pharmaceuticals might be enough to create an individual finger print, if the right detection methods were used.
Slowburn
Hair is so easy to plant.
piperTom
So, the results vary with "diet, ... environment, and working conditions" but still 100 percent accurate. ??! Count me skeptical.
vicman
Ok, so the test accurately identified 13 hair samples, but 13 is too small a samle to say that it "100 percent accurate".
Alonzo Riley
100% accuracy from a sample size of thirteen. The variables include environment and working conditions, so all you have to do is to simply keep the database updated for occupation, and the secret gps chip must not malfunction! Oh, heavenly science.
Mel Tisdale
I assume that this method is best used to assist the police at the start of their investigations while they wait for the much more precise DNA analysis.
Let's face it, any process that has the description: 'solid sampling electrothermal vaporisation inductively coupled plasma optical emission spectrometry with multivariate analysis' has got to have some merit.
pmshah
I think this is great. If within 85 seconds they can narrow down the range of people they are looking for it would be a great start at not giving the possible culprit head start in escaping ! I am pretty sure once they feed more results into their data base it will be able to cover wider range of ethnic differences.
Stephen N Russell
Must for every PD nationwide to acess, & FBI, DEA & Military Police, miscl Police forces & detectives. Sherlock Holmes would use such a device for sure.
JoejustJoe
Diet and environmental factors actually Narrow identification and once they have a sample from the suspect in custody it will confirm that. Now what does it actually prove? One that someone was at a crime might be you or they had access to your dirty laundry (pubic hair from underwear) barber and or hair brush you might even have been Ruffied, passed out drunk or honey trapped and samples taken . As there is no way to determine the point at which the hairs were dropped due to their stability such samples to frame a person for a crime can be months or longer old. Then you have the problem of smart truly vicious criminals covering their tracks by arson as hair is readily burned and it covers destroys many other forensic indicators. Nice tool but it's not the Damning Finger of Justice that they are portraying.
John Banister
This is why criminals raid the trash at barber shops.