The Link between Cannabis and Traffic Collisions
According to a Canadian study, the results of which were published in theBritish Medical Journalin February 2012, acute cannabis users are twice as likely to cause a car crash as those who have not taken any alcohol or drugs. For the purposes of the study, acute use is defined as using cannabis up to three hours before driving. The researchers, from Dalhousie University in Halifax, Canada, are hoping that their findings can be used for educational purposes, because many cannabis users are unaware of the serious impact that their use can have on their driving ability.
TheDalhouse Universityresearchers selected nine studies that looked at cannabis use and drivers, either by toxicological blood analysis or self-report. This involved 50,000 people across the world who had been involved in serious or fatal accidents in a variety of vehicles, including cars, vans, lorries, motorcycles and buses. After taking the risk of bias into consideration, the findings were that accidents caused by people who had taken cannabis less than three hours before driving were more likely to cause a serious accident. However, the effect on less serious accidents was inconclusive and is in need of further research.
As the Canadian study points out, “results from the 2009 Canadian Alcohol and Drug Use Survey have indicated that 11.4% of Canadians overall and 33% of those aged 15-24 years used cannabis at least once in the previous year.” These findings are reflected across the world and, although alcohol still remains the substance most to blame for car collisions, cannabis is more culpable than many people thought, even though previous research has made similar recommendations.
A BBC articlecites a spokesperson from the British Royal Society for the Prevention of Accidents (RoSPA), who claims that a previous study in controlled lab conditions had come up with the same results, but that this substantiating study will add extra power to the argument. A spokesperson for the UK road safety charity Brake corroborates this, claiming that “In the UK, 18% of people killed in road crashes have traces of illegal drugs in their blood, with cannabis the most common.”
There are, however, those who claim that the link between cannabis use and traffic accidents is too vague and more work needs to be done to prove that there is indeed a real link. On the USNational Organization for the Reform of Marijuana Laws(NORML) website, Paul Armentano, Deputy Director, wrote in September 2011 that “While it is well established that alcohol consumption increases accident risk, evidence of marijuana's culpability in on-road driving accidents and injury is far less clear. Although acute cannabis intoxication following inhalation has been shown to mildly impair psychomotor skills, this impairment is seldom severe or long lasting.”
He goes on to suggest that before any form of public policy for the regulation of cannabis use is put into place, technology that enables police officers to test for cannabis use must be widely available.
Other organisations, however, are completely in agreement that there is a need to educate the general public. The Medical Marijuana Industry Group, which is a US organisation that supports medical marijuana dispensaries, has said that it is wholly behind the drive to stop cannabis use and driving and has partnered with theColorado Department of Transportto encourage pharmacists to share information with patients on how their over-the-counter drugs could impair their ability to drive.
