New forensic tool detects ethnicity and gender in single hair

Date: May-30-2014A cutting-edge technique to identify human hair could one day be helping to catch

criminals according to a new study from researchers in Canada.

The tool produces results faster

than current DNA analysis techniques used in law enforcement, and in early tests showed a 100%

success rate at identifying gender and ethnicity.

The new tool is the work of Diane Beauchemin, a professor in the department of chemistry at

Queen's University in Kingston, Ontario, and MSc student Lily Huang. They describe their proof of

concept study in the Journal of Analytical Atomic Spectrometry.

Prof. Beauchemin says her first "foray into forensic chemistry was developing a method of

identifying paint that could help solve hit and run cases." Applying a similar approach to hair

analysis was Ms. Huang's idea, she adds, so they started working on it last year.

Blood samples recovered at a crime scene are often used to identify gender and ethnicity, but

blood deteriorates quickly and is prone to contamination.

However, hair is very stable. The reason it is a promising avenue for forensics is because of the

unique mix of elements it contains, which varies according to diet, ethnicity, gender the

environment and working conditions. They get into the hair from sweat secretions.

The team found they could identify gender from the elements magnesium, sulfur, strontium and

zinc. And to discriminate ethnicity they used lithium, molybdenum, sulfur, strontium, chromium,

potassium, nickel, zinc and lead.

The process takes just 85 seconds to complete. First they grind up the hair sample, burn it

(using a method called electrothermal vaporization), and then analyze the vapor it produces

(using inductively coupled plasma optical emission spectrometry).

Current forensic methods used to analyze hair are time-consuming and use corrosive solvents and

reagents, Prof. Beauchemin told Chemistry World.

Method is robust and can be used universally

Ms. Huang says the method is "very robust and can be used universally. One of our samples even

included dyed hair and the test was 100% accurate. The test was able to distinguish East

Asians, Caucasians and South Asians."

Current forensic methods used to analyze hair are time-consuming and use corrosive solvents and reagents.

The team is already talking to law enforcement agencies about the next step in using the new

method.

And the researchers are also planning to develop the method so it can pinpoint exactly

where in the world a hair sample is from, as well as add more ethnicities and age to the

repertoire.

To extend the repertoire of variables the method can identify means measuring more elements,

but Prof. Beauchemin says this would not take more time, because their detection is

simultaneous.

In 2010, Medical News Today learned how researchers are working on a method

of forensic identification using

hand bacteria. The method uses the fact that when we handle objects we leave behind bacterial

communities that are uniquely identifiable.

Written by Catharine Paddock PhD

View all articles written by Catharine, or follow Catharine on:

Courtesy: Medical News Today Note: Any medical information available in this news section is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional.