B.C. Hospitals to Test Injured Drivers’ Blood Without Their Consent

Injured drivers taken to B.C. hospitals over the next five years will help answer the question: Do those who are high on marijuana cause more crashes than sober drivers?

In the marijuana-impairment study – the first of its kind in Canada – blood will be collected from injured drivers without their permission. Since the data is collected anonymously and not used to pursue legal charges, researchers don’t have to seek approval from drivers to analyze their blood under the ethics-approved terms of the study.

Blood is drawn for treatment of any injuries and the excess amount is then analyzed. The sample is assigned a code that is not shared with police, and the resulting data is then linked to police accident reports to eventually show researchers if cannabis contributed to the accident.

A recent random sampling of B.C. drivers showed that 10 per cent were impaired by alcohol and 7.2 per cent by drugs, usually marijuana or cocaine. After alcohol, cannabis is the most widely used intoxicating substance in the world. In the random sampling, it accounted for about two-thirds of the drugs detected at the police roadside stops, followed by cocaine.

Concentrations of THC, the active ingredient in cannabis, will be measured in the new marijuana study.

It will be led by Dr. Jeffrey Brubacher, an emergency doctor at Vancouver General Hospital.

Many marijuana users think it’s less hazardous because cannabis tends to make people drive more slowly and less aggressively than, say, drivers who are drunk, according to studies.

At the same time, drivers high on marijuana have a harder time staying within lanes and their reflexes are slower, which means they are more likely to crash into obstacles that suddenly appear. On the other hand, “cannabis users tend to overestimate their impairment whereas people who used alcohol underestimate theirs,” Brubacher stated in an explanation of his study in the B.C. Medical Journal.

Brubacher said data on the first 100 injured drivers have already been collected for the study, which aims to include information on 3,000 crashinvolved drivers at five B.C. hospitals. THC levels in blood – which are measurable no matter how the cannabis is consumed (smoked, sprayed, drunk or eaten) – yield a blood THC concentration considered more accurate than THC metabolites in urine. Brubacher said urine metabolites remain active for days after cannabis exposure, even though impairment typically lasts less than four hours.

“Our primary objective is to determine whether injured drivers who used cannabis before a motor vehicle accident are more likely to have caused the crash than those who did not,” said Brubacher, adding that the number of crashes caused by impaired drivers will be compared to a control group of drivers who were found to be not culpable.

The ultimate goal of the $1-million study, funded by the federal Canadian Institutes of Health Research, is to help traffic-safety experts develop safer driving policies. It is possible, for example, that the study might show whether there should be a legal cutoff level for THC blood concentration, just as there is for alcohol. The study results should also help inform the debate around whether marijuana possession should be decriminalized.

When it comes to drug-impaired drivers, current practice is for police to do a roadside sobriety test if they have suspicions. If the driver fails the initial observational tests (walking a straight line, etc.) then the driver must accompany the officer to a police station for further examination by a specially trained drug recognition expert. Drivers may be ordered to submit blood, saliva or urine samples, or face a fine for refusing to comply.

While there have been some surveys showing that drivers impaired by cannabis were nearly twice as likely to crash, Brubacher and his co-investigators are using a similar “culpability” study design as was used in studies in Australia and France, linking data from injured drivers to police reports to show who caused the accident and their level of impairment.

Those studies had a few drawbacks, however, including a cumbersome process in which the drawing of blood was delayed about three hours from the time of the crash.

“We anticipate that our data will provide a more accurate reflection of true THC levels at the time of crash,” Brubacher said, noting that in a pilot project, the average time from crash to blood draw was 53 minutes.

RCMP Supt. Norm Gaumont said he’s pleased the study is being conducted because there is little research on the effects of drug-impaired driving compared to the evidence about the dangers of drunk driving. Gaumont, who heads traffic services in B.C., said there is urgency to get the type of data in the study because of a steady increase in the number of deaths caused by drug-impaired drivers. At last count, B.C. coroners showed there were 62 deaths (out of 374 in 2008) attributable to drugimpaired drivers.

“Drug impairment is becoming a bigger and bigger problem. We’ve done a good job educating people about drunk driving, but [offered]very little on drugs. So certainly this study will be a benefit,” Gaumont said. He added that B.C. lawenforcement authorities are monitoring studies in Europe and Australia, where police are experimenting with roadside saliva tests that can yield instant information about what drugs drivers have used, and their level of impairment.

– Article from The Vancouver Sun.

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  1. undrgrndgirl on

    it is not testing those “under the influence” of cannabis that drive safely (even more safely than other drivers according to the recent australin study) and are never in accidents…the study also has no way to correct for drivers under the influence of cannabis AND one or more other drugs (like alcohol, caffeine, ecstasy, robitussin, prozac, etc., etc.) and there is no way to attribute some portion of “impairment” to one substance and another portion of the same “impairment” to another substance…

    we all know that if driver x is in an accident and s/he tests positive for cannabis and alcohol, the cannabis will be blamed, even if a driver tests for a trace of thc and a bac is 0.16…and tired drivers are even more dangerous than drunk ones…

    just because cannabis is detected does NOT mean it is causing any impairment…

    after reading tons of cannabis studies, i don’t really see how this one would be valuable at all…except to give the (in)justice system some more flawed propaganda to spew…

  2. eyemale on

    It getting to the point everything is a study. what is the big mystery here? you drink or you smoke or do both , you may not be safe to drive or could be a hazard on the road . you could be a hazard on road simply because you never should of been issued a license in the 1st place.

    when you smoke pot it is different than drinking you know how you feel and don’t lose the ability to make decisions . if you think ” hey I feel kind of buzzed” don’t drive . or is that too simple? need data to decide for you? it called a brain ,use it

  3. Anonymous on

    agreed, poeple drinking and geting high will crash as much or more.. but so will drink drivers alone. stoned drivers will be amongst them in the same or a tiny bit more or less numbers than as per the ussual driving population. it all boild down to how the trial is done. they say they will screen a batch of drivers that have not had accidents. if they are testing for some level of thc that means the person could have got stoned the day ( for example, heavy users might have an as high reading as those young drivers that are first timers or irregular users.
    like chronics could drive well and not be impaired yet a young person might be more likley to crash.. so what we might see is a connection between young drivers crashing and then obviously, we also have a connection with younger people using more cannabis.
    so it probably wont show a good result or be worthwhile because it will just show that young cannabis drivers, some of them atleast tend to take risks or be of a risk taker category, and also be experienced and also tend to use drugs more than older people. we know that pot use slows as people get older so right there in the young crash drivers will be the downfall of the study IF they do not recognise that link should be there.

    young people that use pot, will also tend to use alcohol rather than not use anything. older people will be more capable on the roads, experienced and less likley to be high or drunk on any particular day.

    it could be run up against the admited user rates for cannabis across driver licensed in canada. so the tests for non crashing drivers would need to be widespread and also in the same areas that they test the drunk/stoned crashed drivers so that demographics ( different rates of stoners by location) does not come into play.
    and its no good to compare/test only people that have never had an infringment or speeding ticket etc.
    you have to test from all walks of life that dont crash. how they are going to acheive that when they apparently get around this by drawing blood from accident people i am not sure?

    say 10 percent of people smoke pot and drive then you would expect that amount to be in people that dont crash too and 10 percent of those that crash as well..but hey then you have young people that crash more, and also drink more and also get high more. but how do you put it down to the pot use when it could be inexperience on roads and 30 percent of young people smoke pot.
    thats one of the reasons it needs to be in conjunction with a hard core study of young people that do all various things and see what is the real winner. it will be alcohol. then pot will be in their system too in larger amounts than the non drinking young people.

    i think the results of this might be kept on the hush, ussually it shows little connection to crashes and it embarasses them so they dont go braggin about it. but then again. they might not even bother adjusting the results to suit the commmonly known phenomena that young people crash and drink and happen to smoke as well..

  4. Beatnuk on

    Former BC Solicitor General Rich Coleman did suggest that you could consume two or three drinks without being impaired. I disagree with this premise — impairment is measurable at .02 BAC. However, I was curious if this premise also applied to marijuana: that there was a “safe” level of consumption for driving.

    What I expect the research to show is that cannabis and alcohol in combination cause a lot of car accidents, while cannabis alone causes few.

  5. Anonymous on

    I would argue it is unethical taking their blood for one reason, and using it for another, that is likely to eventually be used against them, randomized or not.

    Probably the same draconian fools that came up with penile testing of young sex offenders.

  6. Classyathome on

    Run the exact same blind test on every cop that brings that accident victim in.

    Wanna bet we get some very interesting numbers there???

  7. john b on

    and how long does thc stay in the system you could not of even smoked and still get in a accident and test positive…whats a joke

  8. Anonymous on

    If pot really effects your reaction time enough to matter you’d think you wouldn’t be able to win gold at the winter olympics for snowboarding on it.

    None the less your daily driving shouldn’t depend on your reaction time. I’m a man in my thirties and I’ve been driving since I was 17. Car to test my most stonned reaction time against your average driver with no sense of the car or road beneath them? Your average senior?

    How about that of your average cop? My female cousin is one and she wrote off three vehicles, before becomming a cop. How many since is anyone’s guess. You would think three vehicular write offs would be cause for refusal on the grounds of poor reaction time or decision making?

    It pains me so, to have my fate decided by lesser beings of no sound mind….. I need a damn joint.

  9. Anonymous on

    This is going to be more pseudo science to fuel their previous propaganda that weed is dangerous. They’ve already done a number of such studies. In this case they’ll test for the presence of marijuana, which could very well have been in the system from weeks or months beforehand.

    That their sample size is hardly random but the trauma ward of a hospital where patients have been in car accidents seems to suggest a biased sample. It won’t, and can not, be correlated or quantified with the number of drivers that actually smoke while driving and never have had an accident or infraction.

    You may as well also test if they have white skin and blond hair and draw the same hasty generalization. “Caucasions cause car wrecks”.

    These people do not divulge their data or methods but merely their conclusions, and it is very easy to fit the data to a pre determined conclusion.

    “At the same time, drivers high on marijuana have a harder time staying within lanes and their reflexes are slower, which means they are more likely to crash into obstacles that suddenly appear.

    Get real. Who are talking about here? Someone that’s smoked for the very first time? Or someone that knowns to meter their dose, take a few puffs to take the edge off, calm their frazzled nerves, and concentrate on the road?

    Having someone with no tolerance, or dosing someone beyond their limite where they would typically still feel comfortable driving is just another way to skew the results with bias.

    Also if things “leap out in front of you”, said things typically get run over. Driving does not, and should never, depend on your reaction time. If it does, you’re doing it very wrong and shouldn’t be on the road.

    But let’s ask how things like Tim Hortons affects reaction time? Or the vanity mirror on your sun visor? Cell phone? Car radio?? It’s a non argument.

  10. Anonymous on

    The article fucks up big time early on: it says ‘it measure alcohol, and also drugs’. Alcohol is one of the most dangerous drugs on Earth… I’m guessing it’s the prevalence, social acceptance & promotion of alcohol which allows that falsehood about alcohol to be promoted.

    Alcohol is a drug; it’s more toxic than cocaine & it should be treated like oxycodone or opium… with caution & not used for fun.

    So, stimulating sativa cannabis treats ADD, ADD influences bad driving… I feel very alone somehow, but pot does not make me more dangerous. I’m usually the only one on the road doing the speed limit, I drive defensively, I don’t go with the flow, I don’t follow other cars, I use my blinkers, I don’t forget where I am, I don’t act like Cheech or Chong or Marc Emery, I take it more seriously than others apparently… it’s taboo to promote being on pot all the time, but it’s like being on caffeine all the time. Experienced users are not affected negatively &, quite on the contrary, we are affected positively: we know how to use, we are familiar with the effects & we are as dangerous as caffeine users (if not less dangerous).

    I’m interested in the results; how many crashed drivers are on caffeine? How many are on aspirin? How many are on the legally prescribed amount of speed or downers? How many are on dextromethorphan?