April 26, 2013
Scientists Develop Breathalyzer That Can ‘Smell’ Drugs
Brett Smith for redOrbit.com — Your Universe Online
For years, roadside breathalyzer tests have been an accurate and effective way to determine the blood alcohol level of a motorist and new research from the Karolinska Institutet in Stockholm, Sweden shows a similar device could be used to detect blood levels of cocaine, amphetamines, and cannabis.
According to the Swedish team´s study in Journal of Breath Research, the device returned an 87 percent accuracy rate on individuals at a drug clinic who said they had used drugs recently — the same rate as blood and urine tests performed on the same samples.
"Considering the samples were taken 24 hours after the intake of drugs, we were surprised to find that there was still high detectability for most drugs," said lead author Olof Beck, a toxicologist at the Institute.
In the study, the research team tested the breath of 46 individuals who were checked into a drug addiction emergency clinic and agreed to participate in the study. Each participant was instructed to exhale about 20 times over the course of two to three minutes into the experimental breathalyzer.
The device was able to trap tiny solid and liquid microparticles suspended in the breath for analysis. The small particles replicate the composition of a person´s bloodstream, because molecules from the blood diffuse into the fluid that lines our lungs and is eventually exhaled.
The trapped particles were then tested using liquid chromatography and mass spectrometry analyses that return either a positive or negative result. While most of the detected drugs matched with self-reports and blood tests, 23 percent of the breath tests also indicated the presence of a drug that hadn´t been reported.
The researchers said this degree of accuracy was higher than previous studies, but acknowledged they are slowly refining their system to reduce false positives and improve the detection rate.
In its current state, the new breathalyzer system, called SensAbues, requires a collected sample be sent elsewhere for analysis.
"In cases of suspected driving under the influence of drugs, blood samples could be taken in parallel with breath when back at a police station,” Beck said. “Future studies should therefore test the correlation between blood concentration of drugs of abuse and the concentrations in exhaled breath."
The research team also said advances to reduce cost and increase portability of chemical analysis systems could eventually result in the same type of roadside breath testing for drugs that is currently used for alcohol.
"There is a possibility that exhaled breath will develop into a new matrix for routine drug testing and present an alternative to already used matrices like urine, blood, oral fluid, sweat and hair," the study said. "Since exhaled breath may be as easy to collect as in alcohol breath testing it may present a new more accessible matrix than blood at the roadside."