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What Is a Second Hand High?

what is a second hand high

What Is a Second Hand High?

We have all seen movies where someone is at a party, and everyone around them is hitting a bong or sparking a pre-roll. But they don’t want to smoke themselves. They’re just hanging out for the free food.

It happens in real life too. Some people prefer to “say no to drugs” for a variety of legit reasons. For example, medical professionals cannot use cannabis even if they have a medical card in most cases. People who are in transportation (truckers, pilots, etc.) or machine operators and manufacturing are also prohibited for safety reasons.

So if you are one of those people who fall into the category of “I’ll pass!” then you have probably wondered about testing positive. Even when you haven’t deliberately consumed cannabis. And if you haven’t had that thought, we may have given you something to worry about.

Is THC Active After Cannabis Smoke is Exhaled?

If the term “secondhand high” exists, then surely there must be some merit or at least a prevailing assumption that you can, in fact, get high from secondhand marijuana smoke. If you guessed the answer is “yes!” then you are right.

If you are in an enclosed area with little to no ventilation? Chances are you will start feeling the effects. How long it will take before you get a perma-grin? That depends on a lot of different factors like:

  • The density of cannabis smoke in the room.
  • The concentration or potency of the cannabis being consumed.
  • Your body weight.
  • Whether you are a regular cannabis consumer or not.

If you are someone who never smokes cannabis, your body will not have built up a tolerance to it. Over time, regular use takes more THC to achieve the same psychoactive effects. So long-term marijuana users would be less susceptible to secondhand cannabis smoke. But the person who has never (or rarely) taken cannabis? Buckle up.

Can a Mask Help Reduce Marijuana Smoke Effects?

group wearing masks

On average, it takes less than ten minutes before non smoker exposure to secondhand marijuana provides noticeable effects. Cloth masks won’t protect you from the THC molecules in the air. The cloth fibers allow some fine particulates through.

During the Covid-19 pandemic, the N95 mask became popularized and readily available. This type of mask could reduce the amount of secondhand smoke you inhale. That is because the filters on an N95 mask are designed to catch the smallest particulates (viruses). And it will also work to minimize the absorption of secondhand marijuana smoke.

Secondhand Marijuana Smoke: Side Effects and Risks

It’s well known that secondhand tobacco smoke is almost as bad for you as smoking a cigarette yourself. Cigarette smoke has over 5,000 chemicals and carcinogens (cancer-causing substances). That is why smoking is banned in public spaces, restaurants, schools, and cars where children may be passengers.

But what about secondhand marijuana smoke? You probably think it can’t be as bad for you as breathing in clouds of tobacco. Secondhand marijuana smoke has particulate levels that are even higher than tobacco smoke.

In one study, the Particulate Matter (PM2.5) levels of cannabis were 3.5 times the average emission rate of a Marlboro cigarette. The emissions were measured after smoking pre-rolled marijuana blunts.

Health Risks of Second Hand Smoke

For both tobacco smoke and marijuana smoke, there are health risks. People who smoke (or are frequently in rooms with incinerated tobacco or marijuana) have a higher risk of developing asthma and respiratory irritation. Secondhand marijuana smoke is worse than tobacco smoke, but both present health risks.

An alternative or safer method of smoking marijuana in a group setting is to smoke outside. Traditionally, that’s been a problem since the smell of marijuana is pervasive. But with state legalization of medical marijuana, it is less likely to be a problem. At the very least, cracking a few windows to provide ventilation is necessary.

Types of Marijuana Contact Highs

When you experience (or think you are experiencing) the effects of a drug when you haven’t taken the drug yourself? That’s called a “contact high.” And you can get a contact high from secondhand cannabis smoke.

There are three types of contact highs, according to science:

  • Psychoactive substances (ketamine, psilocybin, peyote, ayahuasca, etc.)
  • Marijuana.
  • Placebos (you can feel impaired even without being exposed to a psychoactive substance).

Is it possible to get a marijuana contact high from an edible? It’s improbable. For example, if you stored cookies in a container that used to hold edibles, not enough cannabinoids would surface transfer from the container.

Getting a contact high from a placebo (with no psychoactive content) is strange. It often happens in pharmaceutical studies, so a placebo test can sometimes provide abnormal results. We think, therefore, we are… high? Placebos take first place as the least harmful type of contact high. Blame the human brain.

What If You Don’t Inhale?

woman considering outcomes

President Clinton will forever be remembered as the man who claimed he didn’t inhale. On March 29, 1992, Bill Clinton was the Governor of Arkansas, and he admitted to trying pot when he was a Rhode Scholar at the University of Oxford.

The statement may have saved his political career but it wasn’t entirely accurate. How capable was Clinton of not breathing for the entire time he was in a college room filled with cannabis smoke? Unless he was wearing a gas mask and an oxygen ventilator, not inhaling secondhand marijuana smoke would have been improbable. It was an entertaining notion.

It doesn’t matter if you do not directly inhale cannabis. By virtue of simply breathing oxygen in the same room, you are ingesting cannabis smoke with every breath you take. This brings us to the next question: can you inhale enough secondhand marijuana smoke to get a positive drug test result?

Will You Fail a Drug Test After Being Exposed to Secondhand Marijuana Smoke?

Ready for some good news? The answer is “probably not.” A new study from Johns Hopkins University was published in the Journal of Analytical Toxicology. And it found that marijuana secondhand smoke exposure is unlikely to cause someone to test positive for THC.

Non-marijuana smokers can breathe a sigh of relief! The study did say that it is not impossible but highly unlikely. In clinical testing, six nonsmokers were seated next to cannabis smokers.

In two instances, there was no ventilation in the room. Imagine getting paid by a University to hot box! And the researchers varied the concentration or potency and density of the cannabis smoke in the room.

Thirteen (13) urine tests determined the nonsmoker exposure over a period of thirty-four (34) hours. Only only person tested positive for THC at levels that would register as a positive result after 6 hours. The other participants were screened at minuscule levels of THC up to 24 hours. After twenty-four hours, however, the nonsmoking (but enthusiastically inhaling) participants had no trace of THC.

Screening Clean After Twenty-Four Hours

urine test

Could you fail a drug test, even if you consumed no cannabis, but your friends did? Possibly if you had a urine screening within the first twenty-four hours. After a day, however, the probability drops to almost zero. You would screen clean. No artificial urine from the head shop required!

But that is on a urine analysis. What happens to other testing methods, such as blood or hair follicle tests? Cannabis can be detected in blood samples for up to thirty days after consumption (or exposure to secondhand marijuana smoke).

Hair follicle tests are very easy to administer and a popular method of testing for THC. A small hair sample can confirm consumption (or exposure to secondhand marijuana) up to ninety (90) days later. And despite product claims, a shampoo from the smokeshop is unlikely to help.

The good news is that secondhand marijuana smoke is unlikely to be absorbed in significant quantities by hair follicles. But if you work in a cannabis cafe or you live with people who use medical cannabis daily, it is possible to absorb THC from secondhand marijuana smoke in your hair follicles.

How to Get Your Ohio Medical Marijuana Card

If you have decided to apply for an Ohio medical marijuana card, we can help. Schedule a telemed appointment from Cleveland, Akron, Dayton, Toledo, Columbus, Cincinnati, or any location across Ohio.

DocMJ is one of the only cannabis healthcare providers to provide a 100% money-back guarantee. If you do not qualify for medical cannabis after consulting with one of our expert practitioners, your visit fee is refunded immediately.

Find out if doctor-supervised medical marijuana in Ohio is right for you. And check our home page for other states we serve.





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