I’m going to say this just to get it out of the way. It’s illegal and unsafe to drive while high or drunk. Drive sober and remember that cars are made of steel and powered by explosives. Be responsible. Your parents were 100% right about this one thing.
Now that the PSA is out of the way, let’s talk about breathalyzers. They’ve been around since the 1950s and generally use a chemical reaction to indicate the presence of alcohol in someone’s breath. If this reaction shows you’re over the legal limit for blood alcohol content (BAC), you get chauffeured to a free room for the evening, and a valet from the city parks your car in a very secure location.
An elevated BAC is enough to get you detained because if it hits a certain level, your judgment and reactions are impaired and it’s not safe for you to drive. You might say you feel just fine, but there’s a stack of peer-reviewed evidence that says otherwise. And science is real.
But guess what? We don’t have the same science for cannabis.
In part, this is because THC doesn’t act the same as ethanol (alcohol) when it’s in your body. Ethanol depresses the nervous system, and the more of it you have, the drunker you get. Period. THC isn’t like that. According to Scientific American, THC “mimics the endogenous neurotransmitter anandamide” and changes nerve signaling. The bodies of experienced cannabis users compensate for this and lessen the reaction. So one person could be impaired by x picograms of THC, and another person would not be.
Why does this matter? Because according to Shelly Baldwin at the Washington Traffic Safety Commission, “There’s only one code for impaired driving, and there’s not always an easy way to determine what’s causing the impairment.” An alcohol breathalyzer can quickly show if your BAC is over the limit, but determining if another substance is involved isn’t as easy. Baldwin says that a blood test is a good way to see if something other than alcohol is involved, but while blood tests are accurate, they require warrants. Warrants can take hours to acquire, giving intoxicants like THC a lot of time to leave the system.
Hound Labs and Cannabix are working on THC breathalyzers that address this time element. Their devices will determine if someone has used cannabis “recently.” Cannabix calls this time two hours, and Hound Labs describes it as “a few hours.” This often corresponds with the time someone could be impaired. However, this, again, doesn’t necessarily correspond to someone being impaired. Trials are underway, and Hound Labs says they’re going to start providing data to scientists for impairment studies that could lead to a per se standard for THC similar to the BAC.
These devices can increase safety by helping determine who is impaired by THC and getting them off the roads legally and quickly before their steel and explosives can do some damage. Something your parents and I approve of.