Teenagers are increasingly turning to vaping to get high — but certain teenagers are more likely to do so than others, according to a new study from the Yale School of Medicine.

The study, which looked at nearly 4,000 teenagers in Connecticut, found that e-cigarette users are particularly likely to vape: Almost one in five has tried vaporizing hash oil and other forms of marijuana. The study also found that male students and younger students are more likely to vape cannabis.

“People have been vaping cannabis for years, so it’s not that this phenomenon is new. But we were just interested in getting some data on how common this practice really is,” said the study’s lead author Meghan Morean, who conducted her research for this study while at Yale, though she has since become a professor at Oberlin.

Morean pointed to the discreet nature of vaping as a potential reason for its popularity among adolescents. The smell is weaker than that of marijuana, making vaping much more concealable and minimizing the risk of students getting caught by universities or the police, she said.

But Morean warned that teenagers might unintentionally consume marijuana, as it is difficult to see what is inside a vaporizer, and they may mistake it for another substance.

Marijuana derivatives such as hash oil are commonly used in conjunction with e-cigarettes. They are perceived as riskier because the concentrations of tetrahydrocannabinol, or THC, the active ingredient in cannabis, can be up to 30 times that of marijuana.

On the other hand, Adam Winstock, a senior lecturer of psychiatry at King’s College London and an addiction consultant, argued that vaporizers are not all that bad.

Winstock also said that, for addicts who cannot quit, making the switch to e-cigarettes is a step in the right direction. Some studies have shown that people who switched from smoking to vaping reported lower rates of respiratory symptoms, he said.

While smoke from vaporizers may contain fewer carcinogens, a factsheet released by the Colorado Department of Public Health and Environment states that vaporizing marijuana can emit toxic levels of ammonia, which are occasionally responsible for pulmonary problems.

Even Winstock acknowledged that there are downsides to vaping.

“There’s the risk that vaporizing might attract people who never would have thought of smoking to use cannabis,” he said. “Vaporizers used with super potent forms of cannabis carry problems.”

Though there is hesitance within the scientific community, students at Yale took a less concerned approach to the idea.

Some students interviewed said they saw it as a moderate alternative to smoking marijuana.

“I would imagine it’s not as bad,” Rayan Alsemeiry ’19 said, calling it “not as severe in terms of health effects.”

James Landefeld ’17 agreed that vaporizers are probably safer.

But students on campus probably do not use vaporizers for marijuana, unlike the study’s subjects.

The study did not establish whether or not vaping has led to an increase in marijuana use. Morean believes there is room for progress in future iterations of the survey.

“We have so many more questions to ask,” she said. “We are still trying to answer so many fundamental questions about e-cigarettes alone.”

By the end of high school, 35 percent of students have used marijuana or hashish, according to a 2014 survey from the National Institute on Drug Abuse.