A bloody solution for forensics scientists
Classroom uses synthetic blood and gets a peek at a potential career
CAMBRIDGE — Students were spilling blood at Southwood Secondary School on Friday, but there was no need to call the police.
Instead, the “crime scene” was inside a science lab where students were conducting experiments on blood splatter patterns, under the direction of a locally raised forensic research scientist.
Theresa Stotesbury, a Southwood grad who’s now a postdoctoral researcher at Trent University, was leading the class as they used her patented synthetic blood that she hopes could one day replace real blood to help train forensic investigators.
It gave the teenagers a taste of the kind of work real forensic
experts do when they’re trying to solve crimes.
“We wanted them to start thinking outside the box in terms of classic lab experiments,” Stotesbury said. “It’s kind of fun to get them engaged in a different kind of science, because you don’t always think about forensics. I remember sitting in their shoes, thinking, ‘What am I going to do with my life?’”
As part of the experiment, the students had to guess how far a blood drop fell by trying to replicate the same pattern using a wooden ruler and dropper.
“This is pretty cool,” said Grade 12 student Sarah Holleran, as she used a smaller ruler to measure the width of her bloodstains, and count the tiny ‘scallops’ that spread out from them.
Stotesbury hopes her fake blood can be used for more experiments like this in the future. The bloodstain kits she helped develop are already commercially available through Trent University.
The problem with real blood, she said, is that it has a short shelf life, it’s hard to source, and there are biohazards and safety risks attached to it. There can also be a lot of time-consuming paperwork involved in getting approval to use it.
“This is for people who may have trouble bringing blood into their lab or into their classroom,” said Stotesbury, who grew up in Ayr and got her master’s degree in forensic science from the University of Auckland.
“We’re not trying to say it’s better than blood, or it’s the new gold standard. We’re just making materials that are similar to blood, and is easier to bring into the lab.”
While the recipe for the synthetic blood is a “trade secret,” it’s essentially a polymer solution that has been refined to behave exactly like blood does, she said. Down the road, Stotesbury hopes it will be able to carry DNA, for training purposes.
“It drips the way blood does, and also spatters the same way blood does, in a crime scene context,” she said.
Jacqueline Deacon, head of the science department at Southwood, said she hoped bringing Stotesbury in would get the students thinking about careers in forensics and other research fields that don’t get as much attention.
“I think the kids need to see scientists who work in areas other than what they’re used to,” Deacon said. “They have a hard time finding out what’s outside their world. So this broadens their horizons.”
Stotesbury bought about 200 millilitres of the fake blood on Friday, enough to last four classes worth of experiments.
“It doesn’t take a lot of blood to make a big mess,” she said. “But luckily, I haven’t had anyone get queasy yet.”