We’ve all seen it before. The second a joint starts getting passed around the room, there is that one hanger-on in the crowd, the one who’s never smoked weed a day in his life, who starts complaining that he’s getting high just from being in the room. This is something referred to as a “contact high,” and there is some controversy over whether it is real or not. If you ask the non-chiefers, catching a buzz simply from sitting around in a room full of pot smoke is legit. Some of the most paranoid of the breed, those who get very uncomfortable in this environment because “I’ve got a good job, bro, that I can’t afford to lose,” will sometimes create a scene. They believe, without a shadow of a doubt, that inhaling somebody else’s good time ganja will cause them to fail a whiz quiz. There are even those who take this social conniption up a notch, and even though they don’t give two squirts about catching a contact buzz or failing a drug test, they do not want to end up with lung cancer or some bizarre brain disease later down the road because of secondhand pot smoke.
So, we here at Cannabis Now dug into the research surrounding this subject to answer the question: Will secondhand marijuana smoke ruin my life?
Will Breathing in Second-Hand Marijuana Smoke Get Me High?
Some of the earliest studies we have on second-hand marijuana smoke suggest that it’s kinda-sorta possible to catch a buzz from this exposure, but not really.
In 1985, researchers stuck five non-marijuana users in a car with five other volunteers who did smoke weed. In order to get the bottom of all of this “contact buzz” business, they essentially “hotboxed” the vehicle – a process in which marijuana smoke fills up a vehicle that is entirely sealed shut – for 30 minutes and then tested to non-smokers to see whether they had any traces of pot coursing through their veins.
Researchers found only small amounts of THC, the high-producing compound of the cannabis plant, in their system. But there wasn’t enough THC in their system to get them high, the study concluded.
Thirty years later, another study, this one conducted by Johns Hopkins University, uncovered slightly different results. This time the subjects – six pot users and six non-users — were put in an unventilated room where the users smoked “10 high potency joints” for a solid hour and then let the scientists do their thing. Following the examination, non-smokers reported effects of marijuana consumption (happy, tired) and “continued to test positive [for THC] for two to 22 hours.”
But, as researchers concluded, this doesn’t necessarily mean that people who breathe in secondhand marijuana smoke are getting high. The study found that only under extreme unventilated conditions would a non-smoker indeed be at risk of a slight contact buzz. Yet, maybe not.
Separate studies have shown that most of the THC consumed by pot smokers is absorbed into their bloodstream before exhaling, so there really isn’t much of the stoner compound floating around the room to contribute to secondhand highs. John Hopkins researchers said that it was possible that any secondhand effects felt by the non-smokers could have been the result of a “placebo effect.”
In other words, just being around the average smoke circle is not going to produce a contact buzz.
But Will Secondhand Pot Smoke Cause Me to Fail a Drug Test?
Researchers with the John Hopkins study concluded that it’s not likely that a person would fail a drug test from exposure to secondhand marijuana smoke. “Cannabis potency and room ventilation” were the two deciding factors. But even if both of these factors came into play, the study found that the amount of THC that could be uncovered in accordance to SAMHSA’s Mandatory Guidelines for Federal Workplace Drug Testing Programs would not show enough to produce a failed test.
This means even if a person was riding around in a car for hours, breathing in Cheech & Chong levels of secondhand pot smoke, they’re probably not going to have any problems passing a drug test.
Need more proof?
A recent report from Dr. Keith Roach, who provides health advice via his column To Your Good Health, finds that secondhand marijuana smoke is not a problem for people worried about failing a drug test.
“Several studies have shown that a person sitting in a car or a closed room where cannabis is being smoked can result in low, but detectable, levels in a person’s urine, even if they were not using the cannabis themselves,” he wrote. “However, most laboratories choose a threshold for calling a sample positive that is higher than was shown to be possible in the passive smoke experiments.”
Okay, But Is Secondhand Marijuana Smoke Harmful to My Health?
Since marijuana remains an outlaw substance in the eyes of the federal government, studies over the ill effects of secondhand marijuana smoke are limited. But there is some evidence that this kind of exposure may increase the risk of blood vessel damage. This conclusion was made after a small study back in 2016 showed that secondhand pot smoke seems to have this effect on rats. But the results appear to have less to do with marijuana and more with the harmful effects of burning plant matter.
Matthew Springer, a biologist and professor in the division of cardiology at the University of California, San Francisco, who oversaw the study, told media outlets last year that toxic chemicals, including carbon monoxide and formaldehyde, are produced when all plant materials are burned. If a person encounters this smoke, regardless of whether it is pot, tobacco or leaves from a tree, there is a good chance they will be exposed to those chemicals. Therefore, “people should think of this not as an anti-THC conclusion, “but an anti-smoke conclusion,” Springer told the folks at National Public Radio.
A report from the Centers for Disease Control and Prevention supports this claim. But it admits that more research is needed before science has an accurate understanding of the effects of secondhand pot smoke on humans.
“Smoked marijuana has many of the same cancer-causing substances as smoked tobacco,” the agency said, “but there are still a lot of unanswered questions around secondhand marijuana smoke exposure and its impact on chronic diseases such as heart disease, cancer, and lung diseases.”
It’s like classic rocker Meatloaf once said, “Two out of three ain’t bad.” We concur. Although secondhand marijuana smoke is not likely to get someone high or jam them up because of a failed drug test, it could present some health hazards. So if you coexist with a non-smoker, limiting their exposure might be the classy thing to do. We feel like cannabis edibles are the great equalizer in this situation. No smoke, everyone is high. This is the purest definition of a win, win.
TELL US, have you ever hotboxed a vehicle?