A new study has found that there is "little difference" between the harmful effects of cigarette smoke and e-cigarette vapour.
Researchers from Queen’s University Belfast carried out the study over three years to assess the impact of vaping on peoples' lungs.
They found that vaping causes an increase in lung inflammation and that bacteria often found in the lungs became more harmful.
Dr Deirdre Gilpin, researcher and lecturer from the School of Pharmacy at Queen’s University and lead author of the research said: “There is currently a knowledge gap about whether vaping is harmful, or less harmful than smoking tobacco.
“Bacteria have long been associated with the development of lung diseases such as bronchitis and pneumonia where smoking plays a role.
"Our study is the first of its kind which aimed to compare the effect of cigarette smoke and e-cigarette vapour on key lung bacteria.
While vaping has often been suggested as a safer alternative to smoking but there is limited evidence to support this.
In recent months, concerns have been raised about the safety of e-cigarettes, particularly in the US where more than 2,000 cases of 'confirmed and probable' lung injury cases were associated with their use.
Additionally, there has been an increase in young people taking up vaping who have never smoked before.
The study "compared the effect of exposure to cigarette smoke extract and e-cigarette vapour on levels of inflammation and the virulence of bacteria commonly associated with lung disease".
Researchers found that exposure to both caused an increase in the potential of bacteria to cause harm in the lungs which could lead to diseases such as COPD and asthma.
This increase in bacteria was similar in cigarette and vaping emissions, and in some instances, the harmful effects of vaping actually exceeded those of smoking.
Dr Gilpin added: “This study shows us that vaping may carry the same risk as cigarette smoke in increasing the susceptibility to bacterial infection.”
Reacting to the findings, the Tobacco Free Research Institute has called for a partial ban on vaping.