Vaping may increase risk of cancer and heart disease, finds study

Nicotine in e-cigarettes could convert into DNA-damaging chemicals

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Smoking e-cigarettes could damage DNA and increase the risk of cancer and heart disease, scientists warn.

Researchers from the New York University School of Medicine said that while it was clear vaping was less harmful than smoking, it was still “dangerous” and should not be promoted as safe.

In laboratory tests, the study found that mice exposed to e-cigarette smoke had higher levels of DNA damage in the heart, lungs and bladder than those breathing normal filtered air.

Likewise, DNA repair systems, which protect against cancer, were also impaired in the animals' cells.

“We propose that ECS (e-cigarette smoke) is carcinogenic and that e-cig smokers have a higher risk than non-smokers to develop lung and bladder cancer and heart diseases,” said team leader Dr Moon-shong Tang.

When testing exposure of nicotine and nicotine derivatives on cultured human lung and bladder cells, there were also similar results with the cells more likely to mutate or undergo tumour-triggering changes than non-exposed cells.

Often regarded as harmless, e-cigarette vapour consists only of nicotine and some relatively harmless organic solvents.

However, despite recent studies showing that e-cigarette smokers have 97 per cent less of NNAL - a lung carcinogen - in their bodies than tobacco smokers, the levels are still significantly higher in those who vape than those who don’t, the study says.

Researchers also reveal that while most inhaled nicotine is broken down into a non-toxic chemical called cotinine, which is eventually excreted in urine, a small proportion, less than 10 per cent, is believed to be metabolised into nitrosamines and their derivatives, which include NNAL.

And, it these chemicals which are capable of inducing tumours in different organs, the scientists pointed out.