Could Secondhand Smoke Cause Someone to Fail A Drug Test?
Drug tests play a big role at work, in legal cases, and in maintaining accountability during treatment.
If you’ve ever had a screening, planned or random, after being around people who were smoking, you are likely wondering:
Can you fail a drug test from secondhand smoke?
In short, it is possible. There are circumstances where you’d be exposed to enough secondhand marijuana smoke to fail a drug test. But it is also unlikely except in certain situations.
This resource from Purpose Healing will answer your questions about secondhand smoke exposure and drug screenings, and guide you on what to do if you test positive after passive exposure.
How Drug Tests Work and Secondhand Smoke Exposure
Standard drug tests detect the presence of drugs or their metabolites, meaning the byproducts created when your body breaks down drugs. All types of screenings work this way, from blood and urine tests to hair and saliva tests.
They are also all very accurate at identifying active smoking, rather than picking up the minuscule amount of substances from exposure to secondhand marijuana smoke.
When you breathe in another person’s smoke, it is possible for your body to absorb trace amounts of the drug. In most cases, it won’t reach the threshold to test positive on a drug test. But this is only in most cases.
Things like being in a confined space, how often and how long you’re exposed, and the type of substance all affect the results of your test. Cannabis potency may also play a role.
People around cannabis smokers, for example, are more likely to have a positive test than someone who’s been around crack or heroin smoke.
Can You Fail a Drug Test from Secondhand Exposure to Cannabis Cigarettes?
Most people who are worried about secondhand smoke leading to a failed drug test are concerned about marijuana. THC, the compound responsible for making you feel “high”, lingers in the area.
When cannabis cigarettes, bowls, and bongs are smoked in an open, ventilated area, it’s rare that you’ll fail a drug test from someone else’s weed smoke. It only happens from heavy exposure.
Small rooms, cars, and other poorly ventilated areas are examples of extreme conditions that might cause higher THC levels. You’re exposed to THC by inhaling smoke from the cannabis plant when it’s burned and from smoke exhaled by other people.
Can You Fail a Drug Test from Exposure to Secondhand Crack Smoke?
Crack cocaine is very potent, so most people smoke it in small amounts. People nearby are likely to notice the odor, or even inhale particles, but it’s very unlikely that you’ll have a positive drug test from secondhand crack smoke.
Cocaine also metabolizes quickly in the body, and drug tests are calibrated to detect active use.
Can You Fail a Drug Test from Secondhand Black Tar Heroin Smoke?
Black tar heroin may be heated and smoked, producing a vapor that can be smelled (and inhaled) by people in the area. The odds of failing a drug screening from secondhand exposure, however, are very low.
Can You Fail a Drug Screening from Secondhand Meth Exposure?
You’re unlikely to have a positive test result after being around someone who is smoking meth. Meth is metabolized quickly by your body. Saliva, blood, hair, and urine drug tests are designed to avoid false positives from environmental contact.
False positives only happen in cases of extreme exposure over an extended period of time. For example, people who live in a home where methamphetamine is manufactured can have high exposure levels even without being around the smoke.
Active Smoking vs Secondhand Exposure to Smoke from Drugs
To understand why secondhand marijuana smoke isn’t likely to make you fail your drug screening, it’s important to distinguish between active smoking and secondhand exposure.
When you are actively smoking, you’re inhaling a concentrated amount of a substance into the lungs. It creates detectable levels of the substance in your bloodstream.
Secondhand smoke results in much lower concentrations. Standardized drug tests and even labs have cutoffs high enough to rule out incidental contact. This means if you’re only exposed to secondhand cannabis smoke, your levels will be significantly lower than they would be if you were smoking it.
How Common Are False Positives on Drug Screenings?
It’s not common for a person to have detectable levels of THC without prolonged exposure and being in a confined space with cannabis users. But some drug screenings are sensitive enough to detect secondhand marijuana smoke.
Once a test does detect THC, it’s sent for a confirmatory screening (like gas chromatography-mass spectrometry or GC-MS). More often, it’s unrelated medications or substances, and not exposure to marijuana smoke, that causes a false positive.
Brief exposure just doesn’t produce enough THC metabolites to be detected by the average urine screening.
What Happens if I Have Failed Drug Test Results?
Passive exposure or not, many people who have a positive drug test result wonder what is going to happen next. The consequences for a failed drug test depend on the reason for the drug test.
If you fail a screening following an accident at work, a positive result might mean being fired. For people on probation, there’s a risk of going back to jail. In legal cases, like with child custody matters, it could impact court decisions or treatment plans.
What Can I Do About a False Positive?
If you honestly believe that you had a false positive test, you can request a confirmatory analysis or second screening. Be honest. If you were exposed to secondhand smoke, especially in an enclosed space, it can help explain borderline results.
It takes a long time for THC metabolites to disappear, but they will decrease with time.
When Secondhand Cannabis Smoke Exposure Becomes a Bigger Concern
Secondhand cannabis smoke generally isn’t enough to give you a positive drug test, but there are situations where it can happen. If you spend hours sitting in a car, basement, or unventilated room where weed is being smoked, you may get detectable THC levels in your body. You may even notice mild psychoactive effects, including drowsiness or impaired concentration. This is called a contact high.
Regular exposure over time can also increase risks to lung health and overall well-being. It is similar to non-smoker exposure to secondhand tobacco smoke.
Find Support if You’re Struggling with Cannabis Use or Other Substances at Purpose
If you’re worried about failing a drug test from secondhand smoke, it’s usually a sign of being in close contact where using substances is common. It’s unlikely passive exposure will cause a false positive, but it can point to a deeper issue. It can be a sign to look at your own marijuana use, or time spent around friends or family who are struggling.
At Purpose Healing, we understand that it’s hard to quit any substance you’ve gotten into the habit of using, even marijuana. It may not have the physical hold of something like opioids, but mentally, it can be just as gripping. We can help. No matter what you are struggling with, our team can help you address substance use and the challenges that come with it.
You don’t have to let drug tests or exposure to secondhand marijuana smoke dictate your future. Support is available, and recovery is possible. Please reach out for support confidentially now.
480-579-3319