Dogs Can Detect One-Billionth of a Teaspoon of Gasoline
According to a recent study from the University of Alberta, trained dogs can detect gasoline in trace amounts as small as one-billionth of a teaspoon (or 5 pico-liters). “During an arson investigation, a dog may be used to identify debris that contains traces of ignitable liquids — which could support a hypothesis that a fire was the result of arson,” explained Robin J. Abel, graduate student in the Department of Chemistry and lead author of the study. “Of course, a dog cannot give testimony in court, so debris from where the dog indicated must be taken back to the laboratory and analyzed.”
But there is a glitch. The trace amounts of gasoline detected by the dogs cannot be confirmed with laboratory analysis. “In this field, it is well-known that dogs are more sensitive than conventional laboratory tests,” said James Harynuk, an associate professor of chemistry and Abel’s supervisor. “There have been many cases where a dog will flag debris that then tests negative in the lab.”
To solve the problem, scientists first needed to know the limits of canine sensitivity. According to a paper titled “A novel protocol for producing low-abundance targets to characterize the sensitivity limits of ignitable liquid detection canines” — published by Abel, Harynuk, and Jeffrey L. Lunder in Forensic Chemistry — the dogs provided no indication at levels of 3 pico-liters or below. Based on the findings of the study, scientists are now attempting to develop a test that will detect gasoline in quantities as minute as that detected by the dogs.