Some flavours of e-cigarette liquid affect male sperm count, UK study finds

E-cig users are now faced with sperm count fears after researchers at University College London claimed that some flavours of vaping fluid, namely cinnamon and bubblegum, may damage sperm if inhaled.

A woman exhales vapour from an e-cigarette. A UK study has shown that certain flavoured liquids used in vaping contain chemicals which could damage fertility. Phil Noble / Reuters

DUBAI // Users of e-cigarettes hoping to start a family are advised to avoid some flavoured liquids after a UK study showed the chemicals used could damage fertility.

Tobacco smoking has long since been linked to restricting sperm production and many smokers are turning to e-cigs as a less dangerous option to achieve a nicotine hit.

However, users are now faced with sperm count fears after researchers at University College London claimed that some flavours of vaping fluid, namely cinnamon and bubblegum, may damage sperm if inhaled.

Further studies completed by the University of Salford, in England, have also shown inhaling some flavours can be more damaging to human lung tissue than unflavoured liquid.

Dr Pankaj Shrivastav, a fertility expert of the Emirates Medical Association, warned his patients daily about the damage done to sperm because of vaping.

“E-cigarettes contain nicotine, so whereas it may not expose the lungs to the same carcinogens and tar as conventional cigarettes, it will still have a damaging affect on the rest of the body,” he said.

“The lining of the testes that produce sperm is different in everyone. Some people can overcome the toxic effects of e-cigarettes but it can have a major effect on men’s sperm production.”

Research in London involved testing 30 samples, with a third of the sperm grown in a dish with propylene glycol, the main chemical used to keep e-cigarette liquid moist.

Two of the best-selling flavours, cinnamon and bubblegum, were added to the other samples and had a significantly negative effect on the number, motility and maturity of the sperm than the normal liquid.

Although harmless to eat, cinnamon can be acutely poisonous when in direct contact with some human cells.

A similar study on nine flavours conducted by University of Salford scientists associated lung damage with menthol and butterscotch vaping fluids.

It was the first study to test inhaled e-liquids on normal lung tissue, and they were found to be to be substantially toxic, with prolonged exposure killing bronchial cells completely.

Although the findings have triggered further warnings, other specialists in the field have dismissed the research.

Medical researcher Dr Konstantinos Farsalinos discussed his study of 20,000 e-cigarette users at the last World Conference on Tobacco or Health in Abu Dhabi.

“The major problem of this study on airway bronchial cells and similar studies is the use of non-standardised protocols, non-standardised doses and the lack of any comparison with tobacco cigarette smoke,” he said.

“In cell studies, anyone can easily generate a toxic response by increasing the exposure dose.

“The sperm study findings are really bizarre. Flavours like cinnamon are widely available in food products, and sperm will be equally exposed to cinnamon derived from food products, since cinnamon is absorbed when ingested.

“The study is basically suggesting that chewing bubblegum and apple-cinnamon pies can cause sperm damage. I find this highly unlikely.”

It remains in the UAE that e-cigarettes are not allowed to be imported or sold but many products are widely used.

Other peer-reviewed research published last year showed e-cigarettes reduce exposure to harmful chemicals in regular cigarettes.

In the blood of both former smokers who now use e-cigarettes and smokers who just quit, levels of carbon monoxide were reduced by 75 per cent.

Dr Shiva Harikrishnan, head of obstetrics and gynaecology at Medeor 24x7 Hospital, Dubai, has reported an increase in e-cigarette use among her patients and advises them to quit smoking and vaping altogether as good family planning advice.

“There is little data on e-cigarettes and pregnancy but we know there is a link between nicotine and also vegetable glycerin used in vaping products,” she said.

“Many patients feel e-cigarettes are safer than regular smoking. We know there are less side-effects and cancer risk but there are other problems that are being discovered as new research is completed.

“I advise my patients trying for a baby to not smoke or vape, to improve their chances.”