WEDNESDAY, Dec. 18, 2019 (HealthDay News) -- As electronic-cigarette use has soared among America's teens, so too has the number vaping marijuana, two new reports indicate.
A team from the University of Nebraska found youth use of pot in e-cigarettes rose from 11% in 2017 to 15% one year later. And University of Michigan researchers found that in 2019, 14% of 12th graders reported marijuana vaping in the prior month, an increase from about 7% in 2018.
These rising rates are concerning for multiple reasons.
"Marijuana use in adolescence could lead to adverse effects on brain development, mental health and academic performance," said Hongying Dai, an associate professor of biostatistics at the College of Public Health at University of Nebraska Medical Center, in Omaha.
"E-cigarette use has also been related to the recent spate of severe lung diseases," added Dai, who led the Nebraska study. The majority of those illnesses are linked to vaping devices containing THC, the main psychoactive ingredient in pot, according to the U.S. Centers for Disease Control and Prevention.
The outbreak has sickened more than 2,400 people and led to 52 deaths. As a result, the CDC has recommended against use of e-cigarettes, or vaping, by all age groups.
"Substance control strategies to prevent vaping marijuana among adolescents and young adults are warranted," said Dai.
For her study, Dai and colleagues gathered data on 38,000 students in grades six through 12 who took part in the National Youth Tobacco Survey.
Dale Gieringer, California director of the marijuana advocacy group NORML, thinks that teens are just responding to new technology.
"Of course, adolescents are vaping more. It's more discreet and convenient than smoking," he said. "It's also healthier, provided of course they're not smoking tainted extracts."
Smoking should be regarded as an obsolescent technology, Gieringer said. "This doesn't mean that adolescents are using more cannabis. In fact, surveys suggest the opposite. It just means they're using more up-to-date technology," he said.
In the other study, researchers were led by Richard Miech, a research professor at the University of Michigan Institute of Social Research. The team used data from the 2018 and 2019 Monitoring the Future surveys of eighth, 10th and 12th graders.
In addition to the increase in vaping among 12th graders, the investigators found that 4% of eighth graders said they vaped marijuana in 2019 -- a jump from less than 3% the previous year. Among 10th graders, nearly 13% said they had vaped marijuana in 2019, up from 7% in 2018.
For 10th and 12th graders, these increases were larger than those seen between 2017 and 2018, the researchers noted.
Also, in 2019, kids who vaped marijuana were twice as likely to be daily vapers, compared with those who hadn't vaped marijuana, the findings showed.
However, "overall teen use of marijuana by any method did not increase in 2019," Miech said.
The bump in marijuana vaping could indicate one of two scenarios. In the first, marijuana vaping is substituting for marijuana smoking, he said. "It could be the case that teens who in the past would have smoked marijuana are now vaping it instead," Miech said.
In the second, marijuana vaping is supplementing marijuana smoking. It could be that teens who use marijuana are continuing to smoke it as before, but they are also vaping it in locations where they can't smoke it, Miech said.
"For example, smoking a joint on school grounds would carry a high risk of getting caught, but vaping less so, because kids can discreetly take a hit on a vaping device and then return it to their pocket," he said.
It appears that the proliferation and access to e-cigarette and vaping products have made it easier for kids to vape marijuana, said Patricia Folan, director of the Center for Tobacco Control at Northwell Health in Great Neck, N.Y.
"With pod-like products, inventions like vaping hoodies, and innovative ways to hide the smell of marijuana, youth may find it easier than ever to use marijuana," she said.
Also, with many states legalizing marijuana, teens, as well as adults, may think this drug is safe and underestimate the lung damage that the ingredients in these products can cause, Folan said.
The reports were published online Dec. 17 in the Journal of the American Medical Association.
Read more on what every parent should know about teens and vaping.