Key points from article :
E-cigarette users could be at risk of lung disease.
Study shows how they can lead to harmful chemical buildups.
Nicotine infused liquids become much more potent cell killers when vaporised.
Majority of research on e-cigarette safety looked at the liquid chemicals.
Still have lower risk of lung cancer than conventional tobacco products.
But manufacturers’ safety claims may be overstated.
The study was published in the Thorax journal.
