By Jan Hoffman

New York Times News Service

A steep rise in nicotine vaping over the past year, accompanied by widespread minimizing of its potential harm, dominated the findings of a closely watched annual survey of American teenagers, released Monday.

The vaping increase was so precipitous, researchers said, it was the largest annual jump in the use of any substance, including marijuana, they had seen in the project’s 44-year history.

In all, the researchers found, the rise amounted to 1.3 million more high school vapers in 2018 than in 2017.

“Vaping is reversing hard-fought declines in the number of adolescents who use nicotine,” Richard Miech, the study’s lead author and a sociologist at the University of Michigan, said in a statement. “These results suggest that vaping is leading youth into nicotine use and nicotine addiction, not away from it,”

The study, called Monitoring the Future, which is sponsored by the National Institute on Drug Abuse and administered by University of Michigan researchers, asks nearly 45,000 students in eighth, 10th and 12th grades about their behavior and attitudes around alcohol and a variety of drugs. More than 1 in 10 eighth-graders said they vaped nicotine in the past year, while 37.3 percent of 12th-graders said they had done so, up from 27.8 percent in 2017.

The percentage of seniors who said they had vaped within the past 30 days — an indication of more frequent use — just about doubled, rising to 21 percent in 2018 from 11 percent in 2017.

Aside from vaping, the study had encouraging news about teenage use of most other drugs.

Tobacco cigarettes continued to remain at historic lows, with only 3.6 percent of high school seniors reporting that they smoke daily, compared with 22 percent two decades ago.

Marijuana levels remained stable, with 5.8 percent of seniors reporting daily use, a level that has stayed pretty much the same over the past 20 years. The study showed teenagers were beginning to move away from opioids and alcohol.

But vaping, predominantly with nicotine but also marijuana, appeared throughout the report as a surging problem. Most e-cigarettes contain nicotine, and the most popular brand among teenagers, Juul, has particularly high levels of it. Nicotine is a highly addictive substance that can interrupt adolescent brain development. And researchers have begun to express concern about the possible long-term effect on the airways of the particles and chemicals in a vape’s aerosol.

But 25.7 percent of seniors who vaped insisted they were inhaling “just flavoring,” suggesting they may not know that many brands use flavored nicotine liquids and salts.