One assessment of the published data on emissions from cigarettes and EC calculated the lifetime cancer risks. It concluded that the cancer potencies of EC were largely under 0.5% of the risk of smoking.
Comparative risks of cardiovascular disease and lung disease have not been quantified but are likely to be also substantially below the risks of smoking. Among EC users, two studies of biomarker data for acrolein, a potent respiratory irritant, found levels consistent with non-smoking levels.
Biomarkers of exposure assessed to date are consistent with significant reductions in harmful constituents and for a few biomarkers assessed in this chapter, similar levels to smokers abstaining from smoking or non-smokers were observed.
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