Almost one-third of high school seniors report using some kind of vaping device in the past year, according to the latest Monitoring the Future survey. Some teens use the devices for nicotine or marijuana, while others use them for flavoring.

“We are especially concerned because the survey shows that some of the teens using these devices are first-time nicotine users,” Nora D. Volkow, MD, Director of the National Institute on Drug Abuse, said in a news release. “Recent research suggests that some of them could move on to regular cigarette smoking, so it is critical that we intervene with evidence-based efforts to prevent youth from using these products.”

Use of hookahs and regular cigarettes declined among high school seniors, the annual survey found. Marijuana use among high school seniors increased from 35.6 percent in 2016 to 37.1 percent in 2017, according to U.S. News & World Report. The survey also found a decrease in high school seniors’ perceptions of the risk of using marijuana.