University of Ottawa researchers Gilles St-Jean and Michelle Chartrand have spent years collecting and analyzing hair from across the country to build a database that will help forensic investigators identify unidentified remains. They hope to have the database up and running by the end of 2012.
On television crime shows, there is already a database for everything, Chartrand says. “In reality, those databases don’t exist. That’s what we’re trying to build here.”
And the clues to building this database are in the water.
When water is consumed, it leaves a chemical fingerprint in hair. And because people tend to drink and cook with their local water, which can vary by region, the signature left on the hair will be geographically unique.
“This is a new tool to help investigators who’ve hit a wall. Sometimes they have no idea where to look,” says St-Jean. “You can get DNA from a body that you’ve found, but if that person never wound up in a DNA database, it’s a useless piece of information.”
Researchers can tell where a person has been by studying the hydrogen and oxygen in the hair. Specifically, they analyze stable isotopes — different forms of the same chemical element — in the hair.
Because hair retains isotopic information, and grows about one centimetre each month, it can provide a personal chronology of where a person has been. If a person moves across the country over the course of a year, that movement will be reflected in the last 12cms of hair growth.
The longer the hair, the longer the trail of footsteps. It’s like having a passport that’s been stamped along the way.
So if an unidentified body is found in downtown Toronto, the person’s hair may indicate they’re not from the city, but a resident of a remote community in northern Ontario — a detail that could prove useful to investigators.
“What stable isotope analysis can do is help us focus our investigation,” says Superintendent John House of the Royal Newfoundland Constabulary. “With a lot of these cases, we have no idea who they are. We don’t know if they’re transients who’ve come in or even if they’re foreigners.”
As of Dec. 1, 2011, there were 205 unsolved unidentified bodies in the OPP database and about 600 unidentified bodies in Canada.
A national database, “would be a very important tool for police,” says House.
The science behind St-Jean and Chartrand’s research has already been applied in Canadian cases. Back in 2006, House suggested stable isotope analysis be used for the first time in a Newfoundland cold case: the Minerals Road skull.
In 2001, hikers trekking through the woods of Conception Bay South, NL, stumbled upon a human skull, wrapped in a plastic bag. Investigators were stumped, despite exhausting many investigative procedures.
After learning about researchers in Europe doing stable isotopic analysis, House sent them samples of the skull and hair, which was 17cms long.
Scientists determined the male victim had lived for extended periods in southern Ontario or southern Quebec, and/or Atlantic Canada. Or, the north-eastern United States. They also noted a blip in the isotopic signature, suggesting he had visited Newfoundland for a brief period about 13 months prior to his death.
Other testing helped estimate the man’s age — he had been born between 1955 and 1961 — and decapitated between 1995 and 1997.
The tests generated new leads, but not enough to crack the case. The Minerals Road skull remains unidentified.
Although the Ottawa scientists are still finalizing their research, they’ve already worked a handful of cold cases with the RCMP and provincial police forces in Ontario and Quebec.
Among the cases is that of so-called Madame Victoria.
In 2001, a badly-decomposed body of a woman in her 50s was found in a wooded area near Montreal’s Royal Victoria Hospital. It’s believed her remains were there for two years.
In January 2010, the coroner’s office sent Chartrand samples of the woman’s hair — It was 43 cms-long, providing 43 months of information. With the hair, Chartrand discovered the woman had moved to seven different locations in the last 43 months of her life, travelling from northern Ontario or Quebec and moving south to Montreal. The longest time she had spent in one place was seven months.
The hair also revealed that in the last five months of her life, she may have been extremely ill, and had likely lost a great deal of weight — a telling detail that helped the facial reconstruction artist.
While the hair analysis didn’t crack the case, Chartrand provided investigators with some insight into Madame Victoria’s movements, diet and health.
To build a database, showing the isotopic components in hair found from coast to coast, Chartrand spent four years travelling across Canada. She collected about 600 different locks of hair, along with samples of the local tap water. In order to obtain a stable signal specific to the region, she sought participants who rarely, if ever, travelled.
This way, when an unidentified body is found the individual’s hair can be compared against the database to try and determine where he or she may have come from.
“We’re always interested in anything that can provide additional information to help investigators,” says RCMP forensic scientist Ron Fourney, who says that even though isotopic hair analysis is still in the early stages of research, “It’s very exciting.”
“It’s another tool in the forensic tool box, a very important one and one that we haven’t seen before,” says Fourney, director of National Services and Research, which falls under the Forensic Science and Identification Services of the RCMP. The agency is working with the scientists to build the database, a project that is being funded by the government agency Centre for Security Science.
In Canada, the hydrogen isotope signals in water vary according to latitude and altitude. As you move north, they tend to become less heavy — a signal that will be reflected in the hair of those who live there.
While this method of hair analysis is gaining popularity in forensic science cases where DNA testing and other traditional means of investigation have shed little light, it does have its own geographical limits.
Scientists can identify regions, but not cities. For instance, they can tell whether someone came from southern or northern Ontario, but can’t pinpoint Kitchener or Kapuskasing.
Also, areas in a region that get drinking water from the same source are lumped together. For instance, the hydrogen isotope signals in hair of people living in Hamilton, Toronto and Kingston will be similar because those cities all rely on Lake Ontario for water.
“When I moved from Toronto to Ottawa and started drinking the local water, my signal started to change immediately,” says Chartrand, explaining that Ottawa gets its drinking water from the Ottawa River, the source of which comes from the north.
Chartrand and St-Jean are still determining the impact hair dye has on isotope values. But, so far, research indicates there’s no change for hair that has been bleached or dyed blond. They’ll also need to analyze, what difference, if any, is there if someone drinks bottled water, or has a daily glass of say Australian wine.
Isotopic signals from other chemicals — carbon and nitrogen — reveal information about a person’s diet and health.
“Everything we consume goes into making our body tissue, including our hair,” says Chartrand. “It is very true that you are what you eat.”
Saturday, January 21, 2012
http://www.thestar.com/living/article/1118732--hair-database-will-help-forensic-investigators-identify-bodies
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