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Vaping and Heated Tobacco Devices Are Toxic to Lung Cells

A new study that directly compares new heated tobacco devices with vaping and traditional cigarettes shows that all three are toxic to human lung cells.

The study, published in ERJ Open Research (, suggests that the new device, which heats solid tobacco instead of an e-liquid, adds to evidence that these newer electronic nicotine delivery devices may not be a safer substitute for cigarette smoking.

The study tested the effects of all three nicotine sources on epithelial cells and smooth muscle cells taken from the human airways. In healthy lungs, epithelial cells act as the first line of defence to any foreign particles entering the airway while smooth muscle cells maintain the structure of the airway. However, smoking can lead to difficulty in breathing by hampering the normal functions of these cells.

The researchers exposed the cells to different concentrations of cigarette smoke, e-cigarette vapour and vapour from a heated tobacco device, and measured whether this was damaging to cells and whether it affected the cells’ normal functions. They found that cigarette smoke and heated tobacco vapour were highly toxic to the cells both at lower and higher concentrations, while e-cigarette vapour demonstrated toxicity mainly at higher concentrations. The concentrations tested represent the levels of nicotine found in chronic smokers.

Lead author of the study, Dr Sukhwinder Sohal of the University of Tasmania, said: “We observed different levels of cellular toxicity with all forms of exposures in human lung cells. What came out clearly was that the newer products were in no way less toxic to cells than conventional cigarettes or e-cigarette vaping.”

Research leader Dr Pawan Sharma of the University of Technology Sydney and the Woolcock Institute of Medical Research added: “Our results suggest that all three are toxic to the cells of our lungs, and that these new heated tobacco devices are as harmful as smoking traditional cigarettes.

“It took us nearly five decades to understand the damaging effects of cigarette smoke, and we don’t yet know the long-term impact of using e-cigarettes. These devices that heat solid tobacco are relatively new, and it will be decades before we will fully understand their effects on human health.

“What we do know is that damage to these two types of lung cells can destroy lung tissue, leading to fatal diseases such as chronic obstructive pulmonary disease, lung cancer and pneumonia, and can increase the risk of developing asthma, so we should not assume that these devices are a safer option.”

Prof Charlotta Pisinger, Chair of the European Respiratory Society’s Tobacco Control Committee, was not involved in the research but commented: “These new heated tobacco devices are marketed as producing 95% lower levels of toxic compounds because the tobacco is heated, not burned. However, the first independent studies have shown that combustion is taking place and toxic and carcinogenic compounds are released, some in lower levels than in conventional cigarette smoke, others in higher levels. A review of the tobacco industry’s own data on these devices has shown that, in rats, there is evidence of lung inflammation, and there is no evidence of improvement in lung inflammation and function in smokers who switch to heated tobacco.

“The introduction and vigorous marketing of new devices is very tempting to smokers who want to stop smoking and mistakenly believe they can switch to another harmless tobacco product. It is also opening another avenue for attracting young people to use and become addicted to nicotine.

“This study adds to evidence that these new devices are not the safe substitute to cigarette smoking they are promoted to be.”