Australian researchers have found that vaping is likely to cause lung and oral cancer, based on a comprehensive review of evidence published in the journal Carcinogenesis. The review, led by the University of New South Wales, analysed animal studies, human case reports, and laboratory research from 2017 to 2025, identifying early warning signs such as DNA damage and inflammation that are strongly linked to cancer risk.
Adjunct Professor Bernard Stewart, a co-author, stated: 'There is no doubt that the cells and tissues of the oral cavity, the mouth and the lungs are altered by inhalation from e-cigarettes.' The review included case reports of oral cancer in individuals who had only vaped and never smoked, as well as animal studies showing increased lung tumours in mice exposed to e-cigarette vapour.
Because modern e-cigarettes were only invented in the early 2000s, there is insufficient long-term data to determine definitive risk. However, the researchers assessed biological changes known to lead to cancer, concluding that e-cigarettes are likely to cause lung and oral cancer, though the extent of the burden remains unknown.
Lead author Associate Professor Freddy Sitas noted that it took decades to recognise smoking as a cause of lung cancer, and warned against repeating that delay with vaping. 'We've always assumed that vapes are safer than cigarettes, but what we're showing is that they might not be safe after all,' he said, urging regulators to act to protect people, especially children.
Professor Stephen Duffy from Queen Mary University London cautioned against overinterpreting the findings, noting that vaping does not involve the combustion products in smoking that have massive carcinogenic effects. However, Stewart emphasised the need to assess vapes in their own right, not just in comparison to smoking.
