Karolinska: New technique enables drugs tests via exhaled breath

Research lead

A study from Karolinska Institutet presents a new technique that makes drug testing possible through exhaled air for the first time.

Working with people who had received emergency care for an amphetamine overdose, the researchers found that in all cases there were traces of amphetamine and metamphetamine in the exhaled breath.

“Traditionally, drugs tests have been carried out using urine and blood samples,” says Olof Beck, who led the study. “In recent years we’ve been trying to find simpler alternatives using saliva, which, unfortunately, has proved difficult. Our results open the way for a new kind of drugs test, which is simple and safe to conduct and that requires no integrity-violating monitoring or medical staff.”

Drugs testing is carried out by healthcare and social services, law enforcement agencies, and in workplaces and schools. While blood alcohol levels can easily be checked in a breathalyser, it is not possible currently to check for other drug compounds in exhaled breath.

Now Beck’s group has developed a new method for collecting narcotic substances from exhaled breath as described in the latest issue of The Journal of Analytical Toxicology. This they did by asking subjects to breathe into a specially designed mask for ten minutes. The exhaled air was collected and passed through a filter, which trapped the narcotic substances. The filters were then analysed using a combination of liquid chromatography and tandem mass-spectrometry.

The researchers took samples from 12 patients who had been admitted into emergency care with toxic symptoms after having taken amphetamines. The samples were taken after the effects of the drug had worn off and with the permission of the regional ethical review board in Stockholm. Ingestion of the drug was confirmed through urine and blood samples.

In all cases, the researchers were able to ascertain the presence of amphetamine and metamphetamine in exhaled breath. The measured excretion rate was between 0.2 and 139 pg/min, which is very low compared to that in blood and urine. No amphetamine or metamphetamine were detected in samples from controls.

The results are convincing and very promising, says Beck. “The study is the first to report the possibility of measuring drugs in exhaled breath, and represents a unique, unexpected finding.”

Beck will now move on to see if other drugs of interest can be detected with this type of breath test, and to develop the sampling and analysis methods.

The study was conducted by researchers at the clinical pharmacology division of the Department of Medicine, Solna and at the Psychiatry Unit at the Department of Clinical Science, Karolinska Institutet, and was financed by Vinnova, the Swedish Governmental Agency for Innovation Systems, the Stockholm County Council and the Swedish Research Council.