Five Fast Facts: Marijuana

Effects of secondhand marijuana smoke last three times longer than cigarette smoke, study says

It’s no secret cigarette smoke can be detrimental to your lungs and heart. However, scientists have recently discovered that marijuana inhalation could be even worse, according to a new study.

» RELATED: This common household chore is as damaging as smoking 20 cigarettes a day

Researchers from the University of California, San Francisco School of Medicine conducted a study, published in the Journal of the American Heart Association, to determine the effects of secondhand marijuana smoke. 

To do so, they examined rats and exposed them to a lit cigarette or marijuana joint for one minute. The animals, which were anesthetized, inhaled the substances while contained in a plexiglass box. 

After analyzing the results, they found the rodents’ arteries had difficulty expanding but returned to normal after 25 minutes. When they were exposed to smoke from the cannabis, the arteries began functioning normally after 90 minutes. 

“People think cannabis is fine because it's ‘natural,’” lead researcher Matthew Springer told NPR. “I hear this a lot. I don't know what it means.”

» RELATED: Just one cigarette can lead to daily smoking, study says

While the scientists noted that regulated cannabis doesn’t have the chemical additives that cigarettes have, any form of smoke is harmful to your lungs, blood vessels and heart. 

“People should think of this not as an anti-THC conclusion but an anti-smoke conclusion," Springer said. THC, or tetrahydrocannabinol, is the active ingredient in marijuana that causes the euphoric high.

Now, researchers hope to continue their investigations and collaborate with the public health experts to warn others about the dangers. 

“We in the public health community have been telling them for decades to avoid inhaling secondhand smoke from tobacco,” Springer said. “We have not been telling them to avoid inhaling secondhand smoke from marijuana, and that's not because it's not bad for you — it's because we just haven't known. The experiments haven't been done.”

» RELATED: Apples, tomatoes could help ex-smokers repair their lungs

Support real journalism. Support local journalism. Subscribe to The Atlanta Journal-Constitution today. See offers.

Your subscription to the Atlanta Journal-Constitution funds in-depth reporting and investigations that keep you informed. Thank you for supporting real journalism.

Related Stories