Teens who vape marijuana have a higher risk of symptoms strongly related to lung injury compared with their peers who smoke or vape nicotine, a new study finds.

The symptoms include wheezing and a dry cough, HealthDay reports. The researchers also found teens who vaped marijuana were more likely to have their sleep, speech or exercise impeded by wheezing.

“I thought that e-cigarettes (vaping nicotine) would be the nicotine product most strongly associated with worrisome respiratory symptoms,” lead researcher Carol Boyd, co-director of the University of Michigan’s Center for the Study of Drugs, Alcohol, Smoking and Health, said in a news release. “Our data challenges the assumption that smoking cigarettes or vaping nicotine is the most harmful to the lungs. If we control for vaping cannabis in our analyses, we find there is a weaker relationship between e-cigarette or cigarette use and respiratory symptoms when compared to vaping cannabis.”