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THC driving limits: Will pot critic William Breathes fail DUI blood test even when sober?

Daily Dose 2011-04-07 0 comments

By William Breathes |  Published in his blog, Mile Highs and Lows

Mr. Breathes holds his breath as his blood is drawn during a test for THC levels for Colorado's proposed DUI bill. (Photo credit: Denver Westword)

​I guess you could classify me as a pretty heavy ganja smoker. To quote Zach Galifianakis, “Sometimes I smoke so much pot that I forget to smoke pot.”

Seriously though, I medicate at least twice a day and I’m fairly sure I have more than 5 nanograms of THC per milliliters of blood in my body at any give time — and that’s the current limit in the proposed cannabis DUI bill.

Should the measure pass, and if my THC blood level is as high as I think it might be, I won’t be able to travel around town without risking an arrest for driving under the influence… even on days when I’m not medicating.

On April 11, a Senate committee is slated to discuss HB1261, which would set impairment limits for driving under the influence of marijuana. The bill would allow up to 5 nanograms of THC per milliliter of blood. Anything over that and a driver would be considered to be driving under the influence.

In theory, the notion of keeping high-as-a-kite drivers off the road is commendable. But is this proposal practical? The Cannabis Therapy Institute is concerned that the measure unfairly targets medical marijuana patients, who might have to submit to forced blood tests or give up their driver’s licenses even if they aren’t high at the time they’re pulled over — just because they have a red medical marijuana card in their pocket. If the law passes,worries attorney Rob Corry, “There’ll be a drastic increase in the amount of people criminally prosecuted.”

Then there’s that 5 nanogram figure, which even Representative Claire Levy, the lawmaker who drafted the bill, admits is arbitrary. The bill would set THC limits much as they are for driving under the influence of alcohol, which is a standard .08 percent blood-alcohol limit.

With booze, the general rule is that a person can metabolize about a drink an hour; drink more than that and your body starts to get drunk whether you have built up a tolerance to the effects of alcohol or not. Although the physical effects may vary depending on how big or small you are, and whether you’re a man or woman, a couple of drinks in an hour will generally put your blood alcohol over the limit… and that alcohol will dissipate a few hours after you drink it.

Pot doesn’t work that way. In short, when you smoke herb, you elevate your levels of active THC and that gets you high. But long after you smoke marijuana, the residual and inactive cannabanoids still linger in your system, binding to the fat cells in your body. So while you might not have smoked herb in as many as 28 days and are sober, for all intents and purposes, you could still register as having THC in your bloodstream.

Beyond that, heavy users build up a tolerance over time, as well as a large amount of residual THC in their system. That puts medical marijuana patients who use a lot of ganja for pain in a tough spot. Even without medicating, they could be guilty of a DUI if this new bill passes.

To test just how high the THC level of a regularly medicating MMJ patient might be,Westword paid $300 to have my blood tested, twice, at Any Lab Test Now in Englewood — the only place we could find that would do the test without a doctor’s recommendation. The idea was to see just how much THC was in my system when I was sober, and how much it jumped after I medicated.

​I put out my final joint last Thursday night around 9 p.m., went to bed and woke up Friday morning without medicating, as I normally would to calm morning nausea and to kick-start my appetite. Around 2 p.m., I drove to the clinic in Englewood (sober as a preacher) to have blood drawn.

I’d like to think that I’m sadly a pro at this by now, having spent a good part of the last decade in emergency rooms and hospitals, but the process of getting poked and my blood taken is never comfortable. My blood pressure was so high that it pushed the needle out of my arm before the nurse was finished, forcing her to ease it back in to get more blood.

After the nurses finished, I went off to burn some herb nearby (I take the Fifth as to where). I wanted to see how fast my THC level could jump, so I power-smoked through about a half-gram bowl of Triple Diesel (at least 18 percent THC) and two massive dabs of Skywalker OG hash oil (at least 80 percent THC) in under ten minutes. I let the meds kick in for another twenty minutes, then headed back to the clinic to see if my blood levels had gotten as high as I did.

Getting jabbed a second time wasn’t as bad, and the nurses had a good time joking with me about how much more lucid I was the second time around. But I know I would not have been as calm if the blood tests were being forced upon me in some random police station after I was unfairly accused of driving fucked up.

Unfortunately, the results aren’t instant: My THC-infused plasma had to be sent off to a lab. The nurses promised my results sometime in the first part of this week, but I’m still waiting — wondering if they will justify my fears that I could be arrested even when I’m sober, just because, as a regular MMJ user, I have a high level of THC in my blood even when I’m not medicating.

As soon as we get the results, we’ll share them with you.