US News 20 March 2018
Family First Comment: “We in the public health community have been telling them for decades to avoid inhaling secondhand smoke from tobacco. 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.”
Now we do!
Exposure to marijuana smoke is three times more harmful than exposure to tobacco smoke, new research suggests.
Matthew Springer, a professor at University of California, San Francisco
School of Medicine, studied the effects of smoke on rats and found exposure to secondhand marijuana smoke makes it harder for arteries to expand and allow a healthy flow of blood.
Springer’s research involved putting a lit cigarette or marijuana joint in a plexiglass box with anesthetized rats. When exposed to tobacco smoke, the rats’ arteries had difficulty expanding for about 30 minutes. However, when exposed to marijuana smoke, the arteries took about 90 minutes to return to their normal function.
“People think cannabis is fine because it’s ‘natural,'” Springer told NPR
. “I hear this a lot. I don’t know what it means.”
“We found that both kinds of smoke had the same effect on blood vessels and that marijuana smoke’s effects lasted at least three times as long as tobacco smoke’s effects,” Springer explained to U.S. News in an email.