August 13, 2018

expert reaction to lab study on the effects of e-cigarette vapour on lung cells

A paper published in Thorax looked at the effects of e-cigarette vapour on lung cells in the lab.

Prof Jonathan Grigg, Professor of Paediatric Respiratory and Environmental Medicine at Queen Mary University of London, said:

“This is a well conducted study focused on a major immune cell at the interface of air and tissue in the lung – the alveolar macrophage. The authors show that alveolar macrophages release potential tissue damaging compounds when exposed to sub-lethal concentrations of e-cigarette vapour condensate.

“This study provides further evidence that challenges the view that vaping presents only minimal risks. The argument that, since vaping is better than smoking cigarettes any effects of vape on lung cells are not important – is increasingly becoming a specious one. First, because airway cells lining the lower airway are exposed to much lower concentrations of nicotine if it absorbed at sites other than the lower airway such as the gut and skin. Second, this study, and other studies using human airway cells and animal models, have shown that non-nicotine constituents of EC vapor also have adverse effects on lower lung cells. By contrast, other methods of smoking cessation will not expose lower airway cells to this complex mix of putative toxins.

“A limitation of this study, acknowledged by the authors, is that it remains difficult to replicate in laboratory studies, the duration and dose of EC vapour that alveolar macrophages are exposed under real-life conditions. However, this study convincingly shows that EC vapour has the capacity to induce adverse effects in these cells.”

Prof John Britton, Director of the UK Centre for Tobacco & Alcohol Studies at the University of Nottingham, said:

“This study demonstrates evidence that lung cells exposed to electronic cigarette vapour become inflamed, as would be expected given that electronic cigarette vapour contains oxidant and other pro-inflammatory constituents. This indicates that long-term use of electronic cigarettes is likely to have adverse effects, as is widely recognised by leading health authorities in the UK including the Royal College of Physicians and Public Health England.

“However, since electronic cigarettes are used almost exclusively in the UK by current or former smokers, the key question is how this adverse effect compares with that of exposure to cigarette smoke. The current study does not address that question, but given the much lower levels and range of toxins in electronic cigarette vapour relative to cigarette smoke, the answer is likely to be substantially less.

“The harsh truth is that smoking kills, and smokers who switch completely to electronic cigarettes are likely substantially to reduce the likelihood of premature death and disability.”

* ‘Pro-inflammatory effects of e-cigarette vapour condensate on human alveolar macrophages’ by Aaron Scott et al. was published in Thorax on Monday 13 August 2018. 

Declared interests

None received.