Scientists today hailed a breakthrough after discovering exactly how e-cigarettes can damage the lungs.
Britons are taking up vaping in unprecedented numbers, with roughly one in ten adults now estimated to be hooked on the habit.
Yet, while vapes are generally considered safer than cigarettes and a useful tool for quitting smoking, until now experts were unsure what makes users more susceptible to serious respiratory illness.
Researchers from Australia now believe that multiple chemicals found in both cigarette and e-cigarette smoke can alter the function of key immune cells in the lungs.
Known medically as MAIT cells, they help fight off bacterial and viral infections and repair damaged tissue.
But smoke from e-cigarettes can stop the cells from working properly, putting users at higher risk of debilitating lung diseases such as chronic obstructive pulmonary disease — also known as COPD.
It comes just a day after the death of former Hollyoaks star Paul Danan, who last year revealed he was rushed to hospital and brought back to life after his ‘obsessive’ disposable vape usage caused respiratory failure.
He took up the habit in the last couple of years after smoking and even admitted he would ‘go to sleep’ with his vape for comfort.
Britons are taking up vaping in unprecedented numbers, with roughly one in ten adults now estimated to be hooked on the habit
It comes just a day after the death of former Hollyoaks star Paul Danan , who last year revealed he was rushed to hospital and brought back to life after his ‘obsessive’ disposable vape usage caused respiratory failure
Professor David Fairlie, an expert in molecular bioscience at the University of Queensland and study co-author, said: ‘While we know that smoke from cigarettes, bushfires, cooking, vehicle exhausts and burning waste pose significant health risks, we still surprisingly know relatively little about how the specific components of smoke affect our immune system and how they impact multiple parts of the human body.
‘We suspected that some of the more than 20,000 chemicals present in smoke that smokers inhale might influence the activity of MAIT cells in the lungs.’
Professor Jamie Rossjohn, an expert in molecular biology and immunity at Monash University and study author, added: ‘We found that long-term exposure impaired MAIT cell protection in mice, weakening their ability to fight influenza and increasing susceptibility to COPD.
‘This shows how, by altering the behaviour of these immune cells, chronic exposure to cigarette smoke can reduce their capacity to combat respiratory infections and increases the risk of chronic inflammation and lung disease.’
E-cigs allow people to inhale nicotine in a vapour — which is produced by heating a liquid, which typically contains propylene glycol, glycerine, flavourings, and other chemicals.
Unlike traditional cigarettes, they do not contain tobacco, nor do they produce tar or carbon — two of the most dangerous elements.
Nicotine’s effect on the brain is well known — within 20 seconds of inhalation, it triggers the release of chemical messengers such as dopamine, associated with reward and pleasure.
But it also increases heart rate and blood pressure and makes blood vessels constrict. This is because nicotine triggers the release of the hormone adrenaline.
Doctors have also expressed fears there could be a wave of lung disease, dental issues and even cancer in the coming decades in people who took up the habit at a young age.
In the study, researchers analysed the effects of cigarette smoke on MAIT cells from human blood and mice.
They found that chemicals, including benzaldehyde derivatives which are used as e-cigarette flavorings, mimic the signals MAIT cells would normally respond to during an infection.
Writing in the Journal of Experimental Medicine, the researchers said the chemicals interact with MAIT cells, suppressing how they work and undermining their protective role.
Long-term exposure to vapes and cigarettes made the mice less able to fight off respiratory infections and more prone to developing COPD, they added.
Professor Alexandra Corbett, an expert in microbiology and immunology at the University of Melbourne and study co-author also said: ‘Our findings offer a new perspective on how cigarette smoke disrupts immune function.
‘With over one billion smokers worldwide, these findings offer a critical step toward understanding and combating smoking-related diseases.’
Around 1.4million people in the UK have COPD. The condition occurs when the lungs and airways become damaged and inflamed.
Campaigners have long blamed predatory manufacturers for the ever-growing crisis, claiming they are intentionally luring kids in with colourful packaging, compared to highlighter pens, and child-friendly flavours such as bubblegum and cotton candy
It’s usually associated with smoking or long-term exposure to certain types of harmful industrial chemicals or dust. However, in some cases, patients can get COPD for no clear reason.
The first symptoms are a persistent cough, excessive mucus production and shortness of breath, which can disrupt sleep.
Over time, COPD increases the risk of life-threatening chest infections.
There is no cure and patients will see their symptoms get progressively worse. Around half of COPD patients will not survive more than five years after their diagnosis.
In the UK, 30,000 people die as a result of COPD every year.
Last year, MailOnline also discovered the number of adverse side effects linked to vaping reported to UK regulators has now eclipsed 1,000, with five of them fatal.
The extensive list includes everything from headaches to strokes. Members of the public and medics can submit them.
In July, in world-first guidance setting out possible interventions to help people stop using tobacco products, the World Health Organization labelled the evidence around e-cigarettes as ‘complex’.
Vapes cannot be recommended as way to stop smoking as too little is known about the harms and benefits, the UN agency said.