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can being around weed smoke fail drug test

Marijuana Research Report
What are the effects of secondhand exposure to marijuana smoke?

People often ask about the possible psychoactive effect of exposure to secondhand marijuana smoke and whether a person who has inhaled secondhand marijuana smoke could fail a drug test. Researchers measured the amount of THC in the blood of people who do not smoke marijuana and had spent 3 hours in a well-ventilated space with people casually smoking marijuana; THC was present in the blood of the nonsmoking participants, but the amount was well below the level needed to fail a drug test. Another study that varied the levels of ventilation and the potency of the marijuana found that some nonsmoking participants exposed for an hour to high-THC marijuana (11.3% THC concentration) in an unventilated room showed positive urine assays in the hours directly following exposure 80 ; a follow-up study showed that nonsmoking people in a confined space with people smoking high-THC marijuana reported mild subjective effects of the drug—a “contact high”—and displayed mild impairments on performance in motor tasks. 81

Toxins and tar levels known to be present in marijuana smoke (see What are marijuana's effects on lung health?) raise concerns about exposure among vulnerable populations, such as children and people with asthma.

Can being around weed smoke fail drug test

A new study finds it is unlikely that a person exposed to secondhand marijuana smoke will test positive for marijuana themselves. While it is possible that extreme marijuana smoke exposure could produce a positive urine test, this occurrence is likely to be rare and limited to the hours immediately after exposure, according to researchers from Johns Hopkins University.

Six experienced marijuana users smoked marijuana with different concentrations of THC, the drug’s psychoactive ingredient, in a sealed chamber. Six non-smokers were seated next to the smokers. In two sessions, the participants were in a room with no ventilation, while in the third session they were in a ventilated room. The non-smokers’ urine was tested 13 times over the next 34 hours. Urine levels of THC surpassed typically detectable levels in only one participant, four to six hours after exposure. When the researchers used a more sensitive test, which is usually not used in workplace drug testing, they could detect lower THC levels, but only for 24 hours.

Non-smokers in the ventilated room did not come close to meeting the threshold for a positive drug test, Newsweek reports.

The findings are published in the Journal of Analytical Toxicology.

A new study finds it is unlikely that a person exposed to secondhand marijuana smoke will test positive for marijuana themselves. While it is possible that extreme marijuana smoke exposure could produce a positive urine test, this occurrence is likely to be rare and limited to the hours immediately after exposure, according to researchers from Johns Hopkins University.