Vaping cannabis could harm your lungs
Two recent studies from The Institute suggest that cannabis vapour may have adverse effects on lung cells
Is vaping cannabis less harmful to your health than smoking it? Many people seem to think so. However, two studies conducted at the Research Institute of the McGill University Health Centre (The Institute) suggest that vaping cannabis may (also) pose risks to lung health.
“Cannabis vaping has emerged as a growing trend, largely driven by the perception that it is safer than smoking. However, its health effects remain poorly understood,” says Prof Carolyn Baglole, PhD, Scientist in The Institute’s Translational Research in Respiratory Diseases Program and senior author of the two studies, which used different methodologies to examine how cannabis vapour affects lung cells. “Our findings show that cannabis vapour, like cannabis and tobacco smoke, contain toxic substances that may increase the risk of health problems in regular users. They challenge the common belief that cannabis vaping is safer for health and highlight the urgent need for further research into its effects on respiratory health.”
Smoking or vaping: similar effects on health
The first study, published in the journal American Journal of Physiology- Lung Cellular and Molecular Physiology, compared the chemical composition of cannabis smoke and cannabis vapour (i.e. the aerosol produced by vaping cannabis), as well as their in vitro effects on human lung epithelial cells, cells that line the airways and are directly exposed to inhaled substances.
The results show that cannabis vapour contains carcinogens, toxic agents for the respiratory tract and teratogens, i.e., agents that can cause congenital abnormalities. The researchers also observed that both cannabis smoke and vapour can generate cellular stress that may trigger changes that could affect respiratory health and increase the risk of cancer.
“Our research shows that the substances found in aerosols from cannabis vaping, when they come into contact with human epithelial cells, induce transcriptional responses (related to gene expression) similar to those caused by cannabis smoke. These reactions are known to pose risks to pulmonary health,” explains Maddison T. Arlen, PhD student at The Institute and first author of the study.
The second study, published in the journal Cell Biology and Toxicology, also suggests that inhaling cannabis vapour alters gene function in lung cells in ways that are associated with cancer, stress and certain immune responses. In this study, researchers used three different models to test the effects of cannabis vapour on human epithelial cell cultures in a lab setting.
The researchers point out that the methods used in these studies have certain limitations, as they do not fully replicate the actual physiological conditions in the lungs. As a result, some toxic elements that could have biological effects may not be captured in these results.
Informing public health policies and raising consumer awareness
Cannabis is the third most commonly used psychoactive substance after alcohol and tobacco. In recent years, several countries have legalized it, which has promoted its social acceptance. However, its illegality throughout much of history has limited research into its health effects. This research is now more necessary than ever.
“These studies are the first to demonstrate that the aerosol produced by cannabis vaping may have a significant impact on lung cell biology, affecting the regulation of genes that play essential roles in inflammatory, cellular and metabolic processes,” says Emily T. Wilson, PhD student at The Institute, first author of the study published in Cell Biology and Toxicology, and co-author of the other study.
“Our research highlights some potential harmful effects of cannabis vaping on health. While there is much more to discover, these findings can help public health authorities better inform the public, reduce risks and guide health policy decisions,” adds Prof. Baglole, also Associate Professor of medicine at McGill University and Director of the McGill Research Centre for Cannabis, a partnership between six McGill faculties and The Institute.
About the studies
The study Transcriptomic changes in oxidative stress, immunity, and cancer pathways caused by cannabis vapor on alveolar epithelial cells was conducted by Emily T. Wilson, Percival Graham, David H. Eidelman and Carolyn J. Baglole.
DOI: 10.1007/s10565-025-09997-3
The study Cannabis vaping elicits transcriptomic and metabolomic changes involved in inflammatory, oxidative stress, and cancer pathways in human bronchial epithelial cells was conducted by Maddison T. Arlen, Stephanie J. Patterson, Michelle K. Page, Rui Liu, Vincenza Caruana, Emily T. Wilson, Stéphane A. Laporte, Maciej L. Goniewicz, Cory S. Harris, David H. Eidelman and Carolyn J. Baglole.
DOI: 10.1152/ajplung.00131.2024
Media contact
Fabienne Landry
Communications coordinator, Research, MUHC
[email protected]