A Belgian research led by University of Leuven chemist and forensic toxicologist Eva Cuypers found decaying human bodies emit specific chemical compounds. This unique scent enables trained canines to find dead bodies during investigations.
Experts use rotten pig flesh to train cadaver dogs because of its similarity to decaying human flesh. The new Belgian research revealed eight compounds unique to both decaying human and pig flesh. Scientists also found five other compounds that can only be found in rotting pig flesh. These five compounds can help separate pig scent from human scent.
The revelation of the "human scent of death" can be used to better train cadaver dogs.
Elien Rosier, a graduate student who assisted Cuypers in the research, placed organs and tissue samples from human autopsied corpses in a jar. Since the jars used are not airtight, the screw caps enabled the air to get inside. Rosier then routinely gathered samples of the gases that formed over time. The research team did the same for tissue and organ samples of pigs, mice, rabbits, frogs and birds.
Pig flesh remains the most similar to the autopsied human flesh. The two share the same microbes found in the gut. The hair and body fat ratio are also close enough. Until recently, the two kinds of flesh had not been studied under the microscope under the same conditions. Cuypers' team discovered 452 organic compounds toward the end of the six-month study.
An independent researcher named Arpad Vass from the University of Tennessee pointed out a flaw in Cuypers' analysis. Vass works in a body farm facility in Knoxville where his team studies decaying human bodies in real-life conditions and under various weather differences.
The subjects in a "body farm" are either submerged in water, buried underground or left in the open air to decay naturally. Vass pointed out that Cuyper's isolated tissue subjects may be a small chunk in the complex bouquet of compounds that develop in actual decaying bodies.
Analytical chemist Dr. John Sagebiel from the University of Nevada also said that the study seemed limiting.
"The next step in our research is to see whether the same compounds are found in buried, full decomposing bodies in the field," responded Cuyper. She added that her team is gearing up to see if cadaver dogs trained on the concoction would respond more specifically to decaying human flesh. This could also mean that a cadaver-sniffing robot might soon replace man's best friend in future investigations.
Still, a dog's sense of smell is hard to beat. In October 2013, cadaver dogs were able to spot the faint scent of a dead body on a buried rug. The dead woman's husband was convicted of murder even though the police were not able to find a body.
Photo: Kenny Louie | Flickr
