E-cigarette vapour destroys protective cells which keep the lungs clear of harmful particles, according to a new study published by the British Medical Journal (BMJ).
According to the small, laboratory-based study, vapour from e-cigarettes impairs the activity of human lung cells called macrophages which are responsible for removing dust, bacteria and allergens.
Some of the damage mirrors that seen in regular smokers and people with chronic lung disease, according to the study which appeared in the BMJ specialist journal Thorax.
Using e-cigarettes, a practice commonly known as vaping, has become increasingly popular in Ireland in recent years both among tobacco smokers trying to kick the habit and young people who have never smoked cigarettes.
Ireland is the third-biggest spender on e-cigarette products per capita (€14.40 in 2017) according to a Euromonitor International report. Only British and Japanese people spend more.
Although it is generally accepted that e-cigarettes are less harmful than tobacco, there have been several recent studies that call into the question the view they are completely safe.
The latest BMJ study is significant as it focuses on the effects of e-cigarette vapour on the lungs rather than on the composition of the e-cigarette fluid.
It found the damage to lung cells caused by vapour was significantly more harmful than that caused by the fluid. Furthermore these effects worsened as the dose increased.
Cell death
The vapour increased cell death by a factor of 50 and significantly increased the production of inflammatory chemicals. The effect was even worse when the vapour contained nicotine, as most e-cigarette do.
The researchers concluded that the vaping process itself increases the damage caused by the e-cigarette fluid.
“Importantly, exposure of macrophages to [e-cigarette vapour] induced many of the same cellular and functional changes in [alveolar macrophage] function seen in cigarette smokers and patients with COPD [chronic obstructive pulmonary disease],” the paper states.
The study's lead author Prof David Thickett said e-cigarettes are safer than normal cigarettes but that research into the area is "in its infancy" and it may be the case that they are harmful in the long term.
“In terms of cancer causing molecules in cigarette smoke, as opposed to cigarette vapour, there are certainly reduced numbers of carcinogens. They are safer in terms of cancer risk, but if you vape for 20 or 30 years and this can cause COPD, then that’s something we need to know about,” he states.
“I don’t believe e-cigarettes are more harmful than ordinary cigarettes,” Prof Thickett said. “But we should have a cautious scepticism that they are as safe as we are being led to believe.”
He added that many e-cigarette companies have been bought by large tobacco firms “and there’s certainly an agenda to portray e-cigarettes as safe”.
