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Can You Fail a Drug Test From Second Hand Marijuana Smoke?


Secondhand Cannabis Smoke = Failing a Drug Test Without Using Drugs?

If you are a veteran marijuana consumer, you have heard of the term ‘contact high’, also known as secondhand cannabis smoke, I’m sure. Maybe you had a friend that was hanging out with you while you were smoking, and they were certain that they had a ‘contact high’ from being around you while you were puffing. Or maybe you knewsecondhand cannabis smoke known as a contact high someone that failed a drug test, and swore that they had never smoked marijuana themselves, but were around people that were. That was the case with NFL player Josh Gordon, who was suspended from the NFL for barely failing a chemical test for marijuana.

For a long time marijuana consumers, and non-marijuana consumers for that matter, were left to wonder if those scenarios were even possible. I know I have hung out with people before that didn’t smoke marijuana, and although they felt like there were getting a contact high, I was pretty sure they were just lame and trying to over embellish. I have heard of many people that have failed drug tests and swore that they didn’t smoke, and I have always wanted to see the science behind what it would take to fail a drug test due to being around second hand marijuana smoke.


Being around enough second hand marijuana smoke to ‘get high’ is a different question than how much marijuana smoke someone would need to be around to fail a drug test. Being ‘high’ is subjective, while the amount of THC in ones system is quantifiable with a chemical test. Just because I have above a threshold for THC in my system doesn’t mean that I’m high at the time of the test because marijuana can stay in someone’s system for a long time, which is something that is common knowledge to anyone who knows anything about marijuana.

Can someone fail a drug test for marijuana when they are around secondhand marijuana smoke, but don’t actually take puffs themselves? According to the results of a study that were published last month, the answer is yes. Below is the abstract from the study:


  • Exposure to secondhand cannabis smoke results in absorption of cannabinoids.
  • Secondhand exposure can produce mild subjective and behavioral/cognitive effects.
  • Room ventilation ameliorates the effects of secondhand cannabis smoke exposure.



Cannabis is the most widely used illicit drug. Many individuals are incidentally exposed to secondhand cannabis smoke, but little is known about the effects of this exposure. This report examines the physiological, subjective, and behavioral/cognitive effects of secondhand cannabis exposure, and the influence of room ventilation on these effects.


Non-cannabis-using individuals were exposed to secondhand cannabis smoke from six individuals smoking cannabis (11.3% THC) ad libitum in a specially constructed chamber for 1 h. Chamber ventilation was experimentally manipulated so that participants were exposed under unventilated conditions or with ventilation at a rate of 11 air exchanges/h. Physiological, subjective and behavioral/cognitive measures of cannabis exposure assessed after exposure sessions were compared to baseline measures.


Exposure to secondhand cannabis smoke under unventilated conditions produced detectable cannabinoid levels in blood and urine, minor increases in heart rate, mild to moderate self-reported sedative drug effects, and impaired performance on the digit symbol substitution task (DSST). One urine specimen tested positive at using a 50 ng/ml cut-off and several specimens were positive at 20 ng/ml. Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results.


Room ventilation has a pronounced effect on exposure to secondhand cannabis smoke. Under extreme, unventilated conditions, secondhand cannabis smoke exposure can produce detectable levels of THC in blood and urine, minor physiological and subjective drug effects, and minor impairment on a task requiring psychomotor ability and working memory.

So according to researchers, yes you can fail a drug test for being around secondhand marijuana smoke. With the case of NFL player Josh Gordon, he tested positive for 16 ng/ml of THC, which was above the 15 ng/ml threshold that the NFL considers to be a failed test. In his appeal he stated that he was just around other people that were smoking marijuana, and based off of this study, I would be inclined to believe him.

So can people get high from being around secondhand marijuana smoke? It’s a subjective question, but yes, I suppose someone could, especially if they had a very low tolerance. If someone is sitting across the room while someone else is on the other side of the room blowing pipe hits out the window in a well ventilated area, then I would probably say no. But if people are sitting in a cramped space, hotboxing like crazy, then I think it’s definitely possible. Especially if the hotbox session includes joints and blunts, where the smoke billows out of the joint/blunt and isn’t the exhale of the hotbox participants. You have to assume that the smoke can accumulate, and even though a person may be in the session area but isn’t puffing, they are going to inhale that ‘non-lung filtered’ smoke.

Moral of the story is, if you are in a position to where you know you are going to have to submit to a drug test in the near future, it’s best to stay upwind of any marijuana smoke. Also, if you don’t want to get high from secondhand marijuana smoke, you probably shouldn’t volunteer to sit in a confined space with poor ventilation while others are puffing away. Do you have any secondhand marijuana smoke stories? They could be personal, or just a story that you heard. If so, make sure to post them in the comments.


About Author

Johnny Green


  1. I live in Cali and we are about to legalize weed in November. Since we are a crazy lawsuit state, If I failed a drug test for work or was driving( I have a DUI) and they wanted a blood test can I sue the state or a company that allows smoking in public places or a outdoor patio area( some outdoor bars allow cigarette smoking)?

    Say if I sit down for a coffee at an outdoor cafe inside the restaurant and someone smokes weed on the other side of the fence in a public area.

    My work has a smoking are just outside of the door I work from, over a day I get high (if I metabolize slowly) and sue my work?

  2. Its quite obvious that everybody’s body metabolizes differently.
    Its the same for prescription drugs. What works for someone might not work on someone else.
    Bottom line is, If you can lose your job for testing positive and you “cant afford to lose your job” Make the smart choice and stay away from it. Or get a different job. The choice is up to you.

  3. I have drug test in few days, friend smoked in the house, central air, ceiling fan off, didn’t blow the smoke my way, but can still smell it. I did not inhale at all, smoke was blown away from me. Will I fail a pee test

  4. I have had it up to my head.I want to do a drug test on .your 5year old son. He’s daddy smoked weed and he really behaves funny and coughs always when he comes back to me. He also applied for custody for our son. I need this test so badly.Trying to find out where I can do it in Berlin.

  5. I’d like to know if there was burning marijuana in the room when being tested (breathing in the smoke first hand) or were they subjected to the exhaled smoke only (second hand smoke)

  6. Never smoked in my life but was with some friends that’s smoked last night(Saturday). I forgot I had a drug test in the morning (not the following tomorrow (Monday). I’ve heard weight, diet, and exercise affect it also-so I’m a 120 lb 5’6 lean runner who drinks plenty of water and clearly exercises regularly. I’ll update this post once I get the results back.

  7. I failed mine guys, ive been smoking fir years, had a number of negative tests for weed results back to back, after one smoke session, which i took no part of, the second hand smoke made me dirty. The oral tests go as low as 12ngl. Be careful guys, the uas only go to about thirty, so if you havent smoke your ngl can be about 15 to 20, youcan see this is an issue. Took an additional tests just in case after the oral test and was negative. Thank god

  8. I sat in living room with people smoking pot I do not smoke anything or drink ,they did not have central air just window unit was there about 3 hours watched a movie they smoked 3 joints during that time ,1 month later I failed drug test my doctor said you can’t get from second hand smoke ,now thanks I smoke ,It was a family member I only get to see 1 time a month as I live 320 miles away so now I can’t go see them at there house anymore.So for people that say you can’t fail test from second hand smoke if don’t have central air or windows open ,you can and will fail

  9. Breann Nelson on

    I had a saliva test done to me for a job. I smoked the entire day before and all I did was brushed my teeth in the morning and rinsed with Listerine and my test came out negative and I got the job.

  10. I am not a smoker but my husband is, hr smokes in the house daily. I just failed a saliva test and haven’t actually used in YEARS.

  11. I have a saliva drug test tommorrow I did a little hit of weed out of a bong on wenesday night around 11 or so 5 days passed already and I have a drug test tommorrow I been eating ice peeing a lot and using golden seal and water and brushing my teeth and using lesterine I wanna know if there’s any chance of me passing this saliva drug test I can’t afford to lose my job Any ones opinion is helpful at this point

  12. I honestly Bro you are hard on this guy a little he doesn’t know that’s why he is asking , and I’m sure things get very difficult when you have family trying to support at this hard times we are all brothers just try to look after eachother I really didn’t know too That too I Thank you for clearing this up I know who to ask next time though.. LOL.

  13. Yeah if your in the world of jobbers maybe. Professionals with college degrees generally don’t. I’m 29 and have never had the humiliation of submitting my urine for testing. But good luck steering clear of random pot clouds getting you high!
    And I’m stupid???

  14. Philip VanDoren on

    Youre both dumb as shit. If I was 15 how could I have quit decades ago. Also I guess you’ve never seen smoke blow down along the ground. Gravity doesn’t make things rise it effects objects based on mass. Smoke rises because it is hotter than the air around it. Get off the dope, get an education. All jobs in my state require a UA unless you’re making minimum wage and BTW dipshit most places these days will just swab your mouth and get an instant result.

  15. Your an idiot and that child is right. And if smoke rises how would it make it 30 yards to you thick enough to get you high. The study says this is only true in extreme conditions… Being outside and smelling it and getting the placebo is totally different… It’s cool bud we were all 15 at one point. Good luck with your job. Better yet go to college and get some real skills and a job that doesn’t require a Ua.

  16. Philip VanDoren on

    “Smoke rises due to the laws of gravity” and you have the nerve to call me stupid. Sit the fuck down child.

  17. this is the dumbest thing i ever heard. drug test yourself before you say some ignorant ass shit like this. like seriously dude. ever heard of the placebo effect? thats what it sounds like. like did smoke enter and exit from your mouth or nose? did you physically see smoke exit from your mouth? if not and it was just smell, then you sir are soooooooo far from properly educated on how marijuana works. smoke travels 10 yards as a whole until it begins to disperse. soooooo…. and also smoke rises. due to the laws of gravity

  18. Philip VanDoren on

    I quit smoking decades ago Because I need to work and keep my job. Last week some thug life kids were smoking dank blunts 30 yards from me in the parking lot at work and I caught a direct wiff and I was high. I could feel it and I was outside yards away. It’s not legal in my state and they are very very strict about this sort of thing. I’ve been told constantly that it’s impossible to fail a drug test from this. But I know what high is and I was high. I’m sure my level is undetectable but this was not even a social interaction..this was from 30 yards away. My boss was an SBI agent and you can’t fool him or even try to tell him something that he doesn’t want to hear. So I’m keeping a low profile at the moment. I really don’t need to be unemployed and homeless at my age over his failure to understand the significance of this study.

  19. My roommate has no tolerance to marijuana but told me 30 minutes ago that she thought she got a “contact high”, so I (having just lit up my second joint for the night) decided to Google it. I found this article (being the second article I’ve read) and I’ve decided that for the most part he’s right. Hotboxing would be the only way to get the sometimes coveted “contact high”. That being said, did you pass your drug test?

  20. Venus Yousif on

    This article is definitely true, I’ve been clean for 2 months and the thc is still showing up in my system. I work at a bar where people occasionally smoke, the ventilation is poor and even though it’s a large space, my piss is still dirty.

  21. Heaven Lee Wilkinson on

    Omg i am the exact same way! My friends and family call me a hypochondriac but im terified of medicine and drugs , i dont even take things for a headache , anyway my bf smokes alll the tome and i do my best not to breath it , i never feel high but i need to pass a drug test tomorrow and am wondering if i will pass

  22. I have a drug test in 4 days and the last time I smoked weed was 3 months ago but last month I was in the car with my mom’s friend and she was smoking weed but her windows where down but I smelled the weed not the smoke so will I pass my drug test??

  23. Siting a study published in a current academic journal is not an opinion. But your response IS an opinion. You should take your own advice and base what you write on facts instead of an angry assault on Johnny Green. Having a BA may not make him a rocket scientist, but he seems to be able to put 2 and 2 together basing his conclusions on published evidence. Nonetheless, thank you for sharing your story.

  24. Sandra Brunell Moberg on

    I have never smoked pot and never plan to. I have anxiety and panic disorder so I worry about everything. So when people smoke pot by me or in the same room I’m in I worry it will affect me. I usually leave because I think it does. I feel weird or buzzed more so than from alcohol. Try avoid it but so many people are doing it. Drugs scare me!! Even to put me on prescription drugs for anxiety I had to be hospitalized so they could reassure me they will help me not hurt me. So I had to Google to see if it affects people being around it or if I just over react.

  25. I was in a room with ppl smoking and i tested positive 25thc twice in one week at my court mandated drug program! Almost went to jail so believe it!… Ps i dont smoke at all….im mandated for alchol.

  26. It’s NOT proven. You can get cancer from second-hand cigarette smoke. You can get high from second-hand weed smoke. Smokers tell others that lie so they can 1.) feel better about the things they are doing & 2.) get as many to share their fate. Misery loves company. The only safe way is to avoid ALL contact… period. I hope you get your job back. Stay strong.

  27. Did calling me a name make you feel better? I don’t smoke or drink. It’s a personal choice. Now, you DID speak on second-hand weed smoke. Get your facts straight BEFORE making comments on topics you aren’t an expert on. A troll? You say the sweetest things…. grow up & get a personality… Fast. Troll? What is this? Kindergarten?

  28. Shaun Nickerson on

    I never said anything about cancer or other effects of secondhand smoke. My comment was about getting high off second hand smoke.

    And yes, it is IMPOSSIBLE to get “high” off smoke someone has inhaled, held and then exhaled. Your body absorbs the THC when it’s inside you. That’s the whole point.

    Fresh smoke that wasn’t inhaled (like the tiny bits the float up from a lit joint) do have THC in them, but that’s not second hand.

    So I am not sure why you feel the need to “point and laugh”. Frankly, I think you’re just a troll who is high and fucked it up.

  29. So, let me get this right. You can get CANCER from second-hand cigarette smoke, but there are NO effects from second-hand weed smoke? I’m just gonna sit here & point & laugh…@ u…..

  30. Andrew Stanford on

    Jeez, what a fucking idiot you are! Second-hand marijuana smoke? Uh, walk the other way.. besides, I don’t see many advocating PUBLIC pot smoking… wow.. what a serious waste of brain activity …

  31. It’s best to never smoke pot period. You don’t need it. You don’t. There are many other ways to improve your life so that you will never have to need to “escape” life through drugs and/or alcohol.

  32. You are severely uneducated on the subject of second-hand marijuana smoke and so it’s best that you not comment on it. In addition, you were a frequent user of street marijuana and, therefore, not a credible source for opinions and data on the negative health effects of second-hand marijuana smoke.

  33. I don’t buy this crap. I joined the US Navy in 2005, i smoked a blunt 2 days before I left for boot camp with a friend and passed every drug test ROTC through at me. In case your wondering its about one a day for the first 5 days in the Navy. You can get contact high sure, but there is not enough nano-grams in your body to make you pop on a test. This is a terrible article written by incompetent people with incompetent knowledge. If your going to provide an article for the masses keep it to the facts and keep your opinions out of it. Your not educating anyone, your letting them know what YOU think.

  34. I totally agree bc I myself have gotten second hand high plenty of times there was actually a few times when I completely quit weed bcof a girlfriend I was with and I loved getting high but she hated it and she knew I’d never lie to her about it bc I’m a paranoid person and can’t lie , but anyways one time I was really stressed out and wanted to get high but I couldn’t I picked up four friends in my car and we sat at the beach for 3 hours while they hot boxed the shit out of my car to points where even they had to get out to be able to breath I did in fact get very very high and I know what a weedinduced high feels like i use to smoke 4 grams daily until pot started to effect my back and stomach, every time I am even exposed to marijuana now I get very paranoid and my belly has a weird pressure feeling in the lower left side near my abdomen people tried telling me there is something wrong with my stomach and the pot is trying to cure it but what I actually think is wrong is pot is the cause of my panic and anxiety disorders bc every time I even seepot now I start to panic people say its in my head witch is very possible bc I had a very bad expiernces on pot that I got from someone that was apparently laced with pcp and I actually got rushed to the er and they found high traces of marijuana and pcp in my system that was the cause of my panic attack , iquit weednowand refuse to smoke it bcof how paranoid it makes me I never want to feel that paranoid I mean I love the head high it gives me but I can’t stand what it does to my body , and today I was with a few friends at there house while they were vaping some weed and I had to get up and leave bc I was starting to feel high after four hours of being in the house with them

  35. Shaun Nickerson on

    You can’t get high off of “Secondhand” smoke. Your body absorbs the THC while that smoke is in you. That’s the point. However, smoke that comes off a blunt or joint that isn’t smoked still has THC in it. And if you aren’t used to smoking weed, you might start getting a buzz if you’re hanging out with friends who are passing around a joint or blunt.

    But you would need to be round them for quite awhile. You would definitely know what they are doing.

  36. What’s the proper bibliographical citation for your “study” described here. One of the most important tests for the scientific nature of a result is whether it can be repeated. Without that, one result such as this awaits confirmation by an independent study.

  37. Dawg kennel kush on

    Find better friends, don’t smoke pot until your 18, and tell your mom she needs to chill and smoke a joint!!!!!!!!

  38. I am a 15 yr old who’s mom had threatened to send me away multiple times for smoking marijuana, two days ago I was with some friends who hotboxed their car with blunts. Sadly I had to sit there and watch but I knew it was worth it cause I wouldn’t fail a test. That was not the outcome I was looking for. I came home today to my mom telling me she already paid $500 for a rehab center for me if I didn’t pass the test. I took the test and it showed up slightly in my system which I was shocked by since I hadn’t smoked in months, my point here is if it’s that serious don’t go close enough to smell or see it. It’s Not Worth It.

  39. Justin Henderson on

    My company was recently bought out by another and all employees were required to pass a drug screening to keep their jobs.i quit smoking for 6 weeks and still failed due to second hand exposure. They told me tht science had proven it could not fail due to second hand smoke and I would have to retest or loose me job. Sumone should inform ameripipe off this study so i can keep my dang job

  40. There is of course Clambaking (getting high in a small enclosed space)
    But Myself the only time I ever got high, from secondhand smoke was in a Cannabis Cup Judges room,
    Just sat down for awhile, got high as hell

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