Novel forensic technique identifies people by their hair
By Ben Coxworth
May 30, 2014
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.
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