Comparing the cancer potencies of emissions from vapourised nicotine products including e-cigarettes with those of tobacco smoke
Abstract
Background Quantifying relative harm caused by inhaling the aerosol emissions of vapourised nicotine products compared with smoking combustible tobacco is an important issue for public health. Methods The cancer potencies of various nicotine-delivering aerosols are modelled using published chemical analyses of emissions and their associated inhalation unit risks. Potencies are compared using a conversion procedure for expressing smoke and e-cigarette vapours in common units. Lifetime cancer risks are calculated from potencies using daily consumption estimates. Results The aerosols form a spectrum of cancer potencies spanning five orders of magnitude from uncontaminated air to tobacco smoke. E-cigarette emissions span most of this range with the preponderance of products having potencies<1% of tobacco smoke and falling within two orders of magnitude of a medicinal nicotine inhaler; however, a small minority have much higher potencies. These high-risk results tend to be associated with high levels of carbonyls generated when excessive power is delivered to the atomiser coil. Samples of a prototype heat-not-burn device have lower cancer potencies than tobacco smoke by at least one order of magnitude, but higher potencies than most e-cigarettes. Mean lifetime risks decline in the sequence: combustible cigarettes >> heat-not-burn >> e-cigarettes (normal power)≥nicotine inhaler. Conclusions Optimal combinations of device settings, liquid formulation and vaping behaviour normally result in e-cigarette emissions with much less carcinogenic potency than tobacco smoke, notwithstanding there are circumstances in which the cancer risks of e-cigarette emissions can escalate, sometimes substantially. These circumstances are usually avoidable when the causes are known.
Citation
Stephens , W E 2017 , ' Comparing the cancer potencies of emissions from vapourised nicotine products including e-cigarettes with those of tobacco smoke ' , Tobacco Control , vol. 21 , no. 1 , pp. 10-17 . https://doi.org/10.1136/tobaccocontrol-2017-053808
Publication
Tobacco Control
Status
Peer reviewed
ISSN
0964-4563Type
Journal article
Rights
© Article author(s) 2017. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1136/tobaccocontrol-2017-053808
Description
© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.Collections
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