Drivers in Spain unwittingly taking part in drug test trial

Saliva Sampler. Image courtesy of SINC

Scientists in Spain have developed a method for detecting 23 different drugs and medicines in saliva. Working with law enforcement at the Directorate General of Traffic (DGT), the researchers have been analysing random samples from drivers since last fall.

Scientists from the Institute of Legal Medicine at the University of Santiago de Compostela have developed a technique for detecting the presence of 23 illegal drugs and medicines in saliva samples. According to Spain’s Scientific Information and News Service (SINC), the “trial” to determine how many drivers use both alcohol and drugs while driving is underway on randomly selected drivers.

The technique, published in the journal Analytical and Bioanalytical Chemistry, is already being used by highway police in Spain.

The saliva sampling began in September 2008 at 32 points throughout Spain and will conclude in September 2009 when researchers expect to have randomly sampled between 3,000 and 3,500 drivers. The DRUID (Driving under the Influence of Drugs, Alcohol and Medicines) project involves 37 international research centers.

Researchers say the method allows law enforcement to differentiate  up to 23 different substances in saliva at the same time, including cocaine, cannabis and amphetamines, and prescription drugs like morphine, methadone, codeine and diazepam. They also tout its non-intrusiveness, and the ability to observe suspects while they are giving samples.

"The saliva samples are collected by putting some cotton on the end of a special device placed under the tongue as if it were a lollipop, with an indicator that turns blue when there is a sufficient sample (0.5 millilitres)," Manuel López Rivadulla, a researcher and co-inventor of the technique, told SINC.

Each driver must submit two samples. One is analyzed on the spot using rapid antigen-antibody immunological techniques, and the other is placed in a tube, labeled and then transported in a refrigerated container to a lab for processing and analysis.

The saliva is analyzed using liquid chromatography, which separates the target molecules, and tandem mass spectrometry, which enables the "unmistakable" identification of different chemical compounds.

The fact that it’s a research trial doesn’t exempt any of the “volunteers” from criminal prosecution if they test positive for any of the controlled substances. The road safety medical advisor said the sampling has already identified some users who face disciplinary penalties and punishments.

A medical advisor to the DGT suggests that the test could be available to all traffic police officers later this year. Law enforcement officials say drug users are an even larger hazard on the road than drunk drivers. Psychoactive substances were detected in 10% of drivers who died on the road, according to the DGT.

Driving under the influence of drugs is being tackled in Australia, too

Down under they call them “drug drivers.”

Australia began giving random saliva drug tests for cannabis, Methylamphetamine and MDMA (ecstasy) along with alcohol level tests in December 2004.

If a driver tests positive for any of the three, they’re required to submit further samples – fluid or blood – which are sent off to a lab for analysis.

Since the program launched, law enforcement officials have found about 300, or 1-in-60, suspect drivers test positive annually. Twenty percent of drivers who are killed on South Australia's roads have illicit drugs in their systems, according to the Herald Sun.

Marta Concheiro, Ana Castro, Óscar Quintela, Angelines Cruz, Manuel López-Rivadulla (2008). Determination of illicit and medicinal drugs and their metabolites in oral fluid and preserved oral fluid by liquid chromatography–tandem mass spectrometry Analytical and Bioanalytical Chemistry, 391 (6), 2329-2338 DOI: 10.1007/s00216-008-2135-4