In the UK, as in many other countries, it is illegal for an individual to drive a vehicle whilst impaired by drugs. In March 2015 a change in the drug driving law was brought in to make it easier for police to stop and prosecute drug drivers.
However, testing for drug driving is not as simple and straightforward as it is for drink driving. For many years now, police have relied upon a breath test to find out if a driver is over the limit. These devices are portable and very accurate and mean that policing the roads for drink drivers is relatively straightforward.
However, when it comes to drugs, a simple breath test is not readily available to police. This means that they must rely on other methods to test for drug usage, normally a saliva or blood test. This makes on the spot testing for drug driving very difficult to implement.
UK Drug Driving Laws
The new UK drug driving law is designed to offer a zero tolerance policy against a total of 16 drugs. 8 of these drugs are commonly used illegal drugs of abuse such as cannabis, cocaine and ecstasy. The remaining 8 drugs are prescription medications that are also used by some for recreational purposes.
Roadside drug tests can detect cannabis or cocaine in a driver’s saliva. However for other banned substances, a laboratory test is required.
In May 2015, just two months after the introduction of the new laws, the Daily Mail reported that six out of ten motorists were failing the new roadside tests. The most commonly detected drug was cannabis, closely followed by cocaine.
A Breath Test for Drugs
A device that can test for drugs using breath is still a long way away from being a reality. In an ideal world, police would be able to test for all 16 banned drugs with a simple drug breath test device that would give instant results, immediately indicating whether a driver was under the influence of drugs. However, the technology for such a device is not currently available.
What about a Cannabis Breath Test?
Even testing for the most commonly abused drug, cannabis is not yet a widely usable reality. Many have tried to develop a cannabis drug breath test but none of the competing systems have yet to take off in any big way.
Difficulties in Testing for Cannabis
All cannabis drug screens are designed to detect THC, the active component in the drug. Even though cannabis use can show up in saliva for up to 24 hours after use, it can be picked up in blood and urine samples for anywhere up to a month.
Existing methods like blood and urine samples therefore make it hard to prove if a driver is actually impaired at the time that they jump into the driver’s seat of a car. Only saliva can do this.
A breath test for cannabis would be a more step forward in preventing drug driving and a few companies are working on finding a way of doing this.
Breath Tests for Cannabis
Here are some of the forerunners in the hunt for a cannabis breath test:
1. Cannabix
Canadian company Cannabix is developing portable drug breathalyzers designed to test exclusively for recent use of Cannabis. This could prove to be of great value to law enforcement officers charged with keeping impaired drivers off of our roads.
The Cannabix system is not on the market yet but when it is, its manufacturers say that it will be able to detect THC use within a two-hour period and offer instant positive or negative results.
2. The Cannibuster
Not strictly a cannabis breath test, but an interesting development nonetheless, the Cannibuster is a smartphone device designed to test levels of THC in minutes using saliva.
3. SensAbues
Designed by a Swedish company, this system detects metabolites in a breath sample using a polymetric filter. It then screens for THC in the laboratory using mass spectrometry.
In tests carried out by the National Institute on Drug Abuse (NIDA), the SensAbues device was used to test the breath of 24 cannabis users (13 frequent smokers and 11 occasional cannabis users) after they have smoked just one cannabis cigarette.
All but one of the occasional smokers recorded a positive result when test using the Swedish device. Over time, the positive results declined. After 1.4 hours 77% were positive. After 2.4 hours, 54% and finally zero after three hours.
It tested the breath of 13 frequent users and 11 occasional users who had each smoked a single marijuana cigarette. The system returned positive results in all but one of the occasional users, with overall positive tests declining with the passing of time: 77 percent of breath samples taken at 1.4 hours tested positive, 54 percent at 2.4 hours and zero at three hours.
4.ElectraTect fuel cell
Researchers at UCLA and ElectraTect are testing a “cannabinoid fuel cell” that can detect THC and measure its concentration in a solution. This technology could be used to develop a marijuana breath analyser similar to alcohol breath tests and provide a more accurate gauge of how much THC is present in a person’s system.
The cannabinoid fuel cell works by using a special enzyme that selectively reacts with THC and generates an electric current. The intensity of this current is directly proportional to the concentration of THC in the solution, allowing researchers to measure the psychoactive component with a high degree of accuracy. In the future, this technology could be miniaturised and incorporated into a handheld device that would allow law enforcement officers to quickly and accurately test for THC on a person’s breath.
Saliva Drug Test for Cannabis – Still the Best Option
Until such time as a commercially available breath test for cannabis is an option, police will need to rely on existing technologies to try and catch drug drivers. A saliva drug test for cannabis is still the most reliable and least invasive way for authorities to check if a driver is under the influence of illegal drugs.
If you would like more information on drug testing, for personal or business monitoring, please contact Zoom Testing and we will try and offer as much reliable advice as possible.
Photo by Anthony Cunningham for Zoom Testing
Zoom Testing is a leading UK drug testing company and a supplier of Drug Test Kits.
This post was originally published in January 2015 and has been updated since.
