The annual Monitoring the Future survey has found U.S. teens are vaping more marijuana and nicotine than a year ago. The survey found 14% of 12th graders said they had vaped marijuana in the last month—almost double the percentage reported last year.

The annual Monitoring the Future survey has found U.S. teens are vaping more marijuana and nicotine than a year ago. The survey found 14% of 12th graders said they had vaped marijuana in the last month—almost double the percentage reported last year.

Teens’ use of drugs other than marijuana continues to decline, the survey found. Their use of alcohol and tobacco cigarettes is also waning, The New York Times reports.

“We are heartened to see the continuing decline in the use of many drugs, particularly non-medical use of prescription opioids; however, teens are clearly attracted to vaping products, which are often concentrated amounts of drugs disguised as electronic gadgets,” Dr. Nora Volkow, Director of the National Institute on Drug Abuse, said in a news release. “Their growing popularity threatens to undo years of progress protecting the health of adolescents in the U.S.”