Vaping 'likely' to cause cancer Scientists have warned that vaping may lead to lung and mouth cancer. 31 March 2026 Vaping could raise the risk of lung and mouth cancer. A woman vaping Researchers from the University of New South Wales in Sydney, Australia, have cast fresh doubt on the safety of e-cigarettes - which have often been marketed as a safer alternative to smoking. The team reviewed a series of studies, including experiments in mice that developed lung tumours after exposure to vape aerosol, alongside reports of heavy users who went on to develop aggressive mouth cancer.