A new study published in PLOS ONE reports that the respiratory epithelial cells of a mouse exposed to electronic cigarette vapour showed signs of inflammation and oxidation stress. Similarly, a mouse exposed to electronic aerosol experienced reduced pulmonary bacterial clearance. The study is somehow shocking, right?
There is only one problem from the study with the alarmist headline being spread by the media and the alarming conclusion: they are not supported by scientific evidence. Let’s face the facts, the study was conducted on mice, and it is in the public domain that there are serious problems with extrapolating from the findings in mice to meaningful clinical finding in humans. What the study demonstrated was something everybody knew: that electronic cigarette aerosol may cause irritation in respiratory. The question of whether that respiratory irritation could result into a serious clinical lung disease remains unknown. Secondly, there is no evidence at the moment to show that there are any clinically adverse effects on the use of electronic cigarettes.
The only existing evidence is that switching from traditional smoking to electronic can reverse a certain form of obstructive airway diseases. In fact, the study indicates that the consistent use of electronic cigarettes instead of tobacco smoking is associated with subjective and objective improvement in asthma results. Considering that the electronic cigarette use is apparently less harmful compared to traditional smoking with subsequent positive outcomes in asthma, this new study has a valid evidence that the electronic cigarette is the best option for asthmatic people who may not quit smoking using other methods.
The study of respiratory epithelial cells of a mouse is nearly identical to the one which found that mice treated with aspirin exhibit reduced bacterial clearance from their lungs. Based on the study, would researchers successfully conclude that aspirin cause pneumonia in humans, and the media to disseminate to the public that aspirin increase the risk of bacterial infection? Obviously, such quick conclusion would have been premature, thus the extrapolating danger from mice to men.