A new report from the Atlanta-based Centers for Disease Control and Prevention revealed that more than 2 million American teens have used an e-cigarette to vape marijuana
The new data, based on a representative sample of middle and high school students questioned in the 2016 National Youth Tobacco Survey, showed 8.9 percent of the 20,000 students surveyed had smoked cannabis via e-cigarettes. That means nearly 1 in 11 students answered, "Yes, I have used an e-cigarette device with marijuana, THC [tetrahydrocannabinol] or hash oil, or THC wax."
Nearly 1 in 3 high school students and about 1 in 4 middle school students reported using cannabis in the devices, amounting to about 2 million young people nationwide — figures much higher than researchers previously predicted.
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The number is worrying "because cannabis use among youth can adversely affect learning and memory and may impair later academic achievement and education," said lead CDC researcher Katrina Trivers.
Vaping is generally considered less dangerous than smoking, because burning tobacco or marijuana generates chemicals that are harmful to lungs. But there is little research on e-cigarettes' long-term effects, including whether they help smokers quit.
The rise in teenagers using e-cigarettes has alarmed health officials who worry kids will get addicted to nicotine, a stimulant, and be more likely to try cigarettes.
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"Shifts in social acceptability and access to cannabis could occur as several states consider legalized cannabis sales for adults," the researchers wrote in a letter published in JAMA Pediatrics on Monday.
The letter comes on the heels of a recent statement from Food and Drug Administration Commissioner Scott Gottlieb, who last week declared youth vaping an "epidemic." The FDA gave the five largest e-cigarette makers 60 days to produce plans to stop underage use of their products.
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"In the largest coordinated enforcement effort in the FDA's history, the agency issued more than 1,300 warning letters and civil money penalty complaints (fines) to retailers who illegally sold JUUL and other e-cigarette products to minors during a nationwide, undercover blitz of brick-and-mortar and online stores this summer," the agency news release stated.
While critics have often argued vaping is a partial solution to America's cigarette smoking crisis, Gottlieb said there are "clear signs that youth use of electronic cigarettes has reached an epidemic proportion."
“Teenagers are becoming regular users, and the proportion of regular users is increasing,” he added. “We’re going to have to take action.”
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It's unclear whether marijuana vaping is increasing among teens or holding steady. The devices have grown into a multi-billion industry, but they are relatively new.
The Associated Press contributed to this story.