Cancer potencies and margin of exposure used for comparative risk assessment of heated tobacco products and electronic cigarettes aerosols with cigarette smoke.

Introduction:
This text provides an analysis of the health risks associated with the use of heated tobacco products (hTPs) and electronic cigarettes (ECs) compared to traditional cigarettes. The study combines margin of exposure (MOE) and cancer potency values to quantify cancer and non-cancer risks for hTPs and ECs based on available compound-specific toxicological threshold references from regulatory agencies.

Key Points:

* The study analyzed hPhC yields from 273 cigarette brands, 8 hTP brands, and 2 ECs.
* Cancer potency was determined for selected compounds and translated to mean lifetime cancer risk.
* MOE values were calculated for each compound and combined into MOET values for cigarettes, hTPs, and ECs.
* Statistical analysis showed a significant difference in mean lifetime cancer risk and MOET values between cigarettes and hTPs or ECs.
* The study found that hTPs and ECs have a large decrease in estimated cancer and non-cancer risks compared to cigarettes.
* Limitations include the selection of specific hPhCs, availability of IURs or IELs, and criteria developed for their selection.
* The chemical characterization of hTP and EC aerosols is an ongoing activity, and compounds with potential toxicological concern may have been missed due to current analytical technology limitations.

Main Message:
The study suggests that hTPs and ECs may be a justifiable alternative for legal-age smokers unable or unwilling to quit smoking, as they lead to an appreciable risk reduction in comparison to cigarettes for both cancer and non-cancer diseases. however, further research is needed to estimate health risks associated with chronic nicotine exposure and determine an IEL level related to potential chronic health effects other than addictiveness.

Rodrigo G, Jaccard G, Tafin Djoko D, Korneliou a, Esposito M, Belushkin M. Cancer potencies and margin of exposure used for comparative risk assessment of heated tobacco products and electronic cigarettes aerosols with cigarette smoke. archives of toxicology. 2021;95(1):283-298. doi:10.1007/s00204-020-02924-x