The notion of secondary contact high has been around for ages, but is it something that really happens? If you are not familiar with the term, a secondary contact high describes the idea that you can get high just by being exposed, secondhand, to marijuana smoke.
In situations like this, someone who is not smoking can be concerned that the people who are smoking around them can affect them, inhibiting their perception and motor skills. Many people wonder if you can actually get high from being in the presence of marijuana smoke or if it is directly blown in your face.
Is Getting a Contact High a Real Thing?
Research has shown us that there is a very low likelihood that you can actually get a contact high from being in the presence of marijuana smoke. The only studies that suggested getting a contact high may be possible were ones in extreme circumstances in which an excessive amount of smoke was blown directly into the face of the subject. In extreme cases like these, someone may get high, and they could possibly fail a urine test.
What these studies have shown is that only trace amounts of THC are pushed back into the air when a smoker exhales. These studies showed that even if you were sitting in a small enclosed room with multiple people in your direct vicinity smoking marijuana, you still would not get high.
Can You Fail a Drug Test from Getting a Contact High?
The likelihood of failing a drug test from a contact high is possible, but again, there is a very low likelihood that this could happen. You would need to be exposed to a high volume of marijuana smoke, from multiple smokers, in an enclosed area for hours to get a noticeable amount of THC in your system.
While secondhand marijuana smoke can result in the absorption of small amounts of THC, the levels of THC that would accumulate in your system from passive exposure are generally too low to trigger a positive drug test. However, there are certain conditions under which passive exposure could potentially lead to a failed test, depending on various factors such as the type of drug test, the intensity of exposure, and the time frame involved.
Understanding Drug Tests and THC Detection
Drug tests typically detect THC or its metabolites in urine, blood, or hair. The most common type of drug test is a urine test, which looks for the presence of THC-COOH, a metabolite that is created when THC is broken down in the body. The threshold for a positive test result is generally set at 50 ng/mL of THC-COOH for urine tests, though this can vary depending on the testing protocol.
Since THC is fat-soluble, it can stay in your system for an extended period after use, especially if you consume marijuana frequently. However, passive exposure to secondhand marijuana smoke usually results in much lower concentrations of THC in your system, which would likely be below the detectable threshold for a drug test.
Factors That Could Influence the Likelihood of Failing a Drug Test
Level of Exposure: The amount of THC that you would absorb from secondhand marijuana smoke depends on how concentrated the smoke is in the environment and how long you are exposed to it. In a poorly ventilated area with heavy marijuana use, the likelihood of absorbing more THC is higher. However, even in such conditions, it’s still rare for someone to inhale enough THC to exceed the testing threshold.
Type of Drug Test: Different drug tests have different sensitivities to THC. Urine tests, which are most commonly used, can detect THC metabolites even after significant consumption, but they would generally not pick up trace amounts from passive exposure. Blood tests, however, can detect recent consumption more directly, and the presence of THC in blood can decline quickly. Hair tests can detect long-term use but are less sensitive to short-term exposure.
Duration and Proximity of Exposure: If you are exposed to marijuana smoke for an extended period or are in close proximity to someone smoking, you might absorb slightly more THC than if you were only exposed briefly. However, unless you are in a very small, poorly ventilated area where marijuana is smoked heavily for an extended period, the amount of THC you would inhale is unlikely to be enough to cause a failed drug test.
Personal Factors: Your body composition, metabolism, and how often you consume marijuana can also influence the way THC is processed in your system. Some people metabolize THC more quickly, while others may retain it for longer periods, especially if they have a higher body fat percentage.
Are There Negative Health Side Effects of Secondhand Marijuana Smoke?
This is a question that studies are still trying to answer. As of now, we do not have any definitive evidence that shows that secondhand marijuana smoke can cause damage similar to that of secondhand smoke from cigarettes. The answer to this is something that is still being explored.
Other Options to Minimize Secondhand Marijuana Smoke
Thankfully, there are other options for consuming marijuana that totally eliminate secondhand smoke.
Use of Cannabis-Infused Products
Marijuana edibles and topicals are other options you can consume around non-smokers that do not produce secondhand smoke.
Edibles and Drinks: Cannabis-infused edibles and drinks are consumed orally; no smoking required. While there is still a risk of overdose or adverse effects from consuming too much, edibles offer a smoke-free experience that doesn’t affect others.
Topicals: Cannabis-infused creams, balms, and oils applied directly to the skin provide therapeutic benefits without smoking. These products don’t produce secondhand exposure, which is perfect for those looking for a non-invasive way to use them.
Designated Smoking Areas
One of the best ways to minimize secondhand marijuana smoke is to create designated smoking areas. By having a specific, well-ventilated outdoor space where marijuana is allowed, people can enjoy cannabis without affecting others.
Outdoors vs. Indoors: Smoking marijuana outdoors reduces the chances of smoke entering indoor spaces where it can linger and affect others. If smoking indoors is necessary, having a well-ventilated area with air purifiers or exhaust systems can help minimize the spread of smoke.
Ventilation and Air Filtration
Proper ventilation is key to reducing secondhand marijuana smoke in the air. In spaces where marijuana is smoked indoors, increasing airflow can help disperse the smoke and minimize its effects.
Exhaust Fans: Installing exhaust fans in rooms where marijuana is smoked can remove smoke from the air. These fans should be directed outside so smoke doesn’t linger inside.
High-Quality Air Purifiers: Air purifiers with HEPA filters can trap small particles in the air, such as smoke and other pollutants. While they may not remove all harmful chemicals, they can reduce overall airborne toxins, making the environment safer for non-smokers.
Open Windows and Doors: If possible, opening windows and doors to allow cross-ventilation can help disperse smoke more quickly, reducing the time it stays in the air.
In Summary
While the idea of a secondary contact high is intriguing, scientific research shows that the chances of getting high from passive exposure to marijuana smoke are very minimal. Most studies show that it’s only minimally possible under extreme circumstances, like being enclosed in a small space with a large amount of smoke blowing directly at you.
For the average person in everyday life, the risks of impaired perception or motor skills from secondhand marijuana smoke are low. But it’s still important to be aware of your surroundings, especially in situations where heavy marijuana use is happening. Knowing the dynamics of exposure can help ease worries, but caution and awareness are always key to a safe and healthy environment.

Aaron Bloom serves as the CEO, overseeing the mission and growth of DocMJ and Medwell Health and Wellness Centers. Aaron’s passion for improving patients’ lives comes from his background in health care. For more than 20 years, Aaron owned, operated, and represented traditional healthcare organizations. This experience created a passion for finding improved ways to relieve suffering. His goal as CEO is to work daily to relieve all patients who seek better health and wellness through the medicinal benefits of medical cannabis and evidence-based alternative medicines.