Electronic cigarette aerosol induces significantly less cytotoxicity than tobacco smoke

Introduction:
This article reports a study comparing the cytotoxicity of tobacco smoke and electronic cigarette (e-cigarette) aerosol using an adapted Borgwaldt RM20S exposure system and a quartz crystal microbalance (QCM) dosimetry analysis method. The study also investigates the cytotoxic response of an in vitro human bronchial epithelial model to aerosols generated from a higher delivery Vype ePen e-cigarette and 3R4F cigarette.

Key Points:

* The study used the Borgwaldt RM20S smoking machine adapted to generate and deliver e-cigarette aerosols from two different commercially available products (Vype eStick and ePen) to an in vitro exposure chamber.
* A dosimetric analysis method using QCMs was employed to detect and compare the aerosol dilutions entering the exposure chamber, and to measure the deposited mass between the two e-cigarettes and a reference Kentucky 3R4F cigarette.
* The study found that the Vype ePen aerosol was significantly less cytotoxic than 3R4F cigarette smoke, both in terms of aerosol dilution (97% less cytotoxic) and deposited mass (94% less cytotoxic).
* The test doses where cigarette smoke and e-cigarette aerosol cytotoxicity were observed are comparable with calculated daily doses in consumers.
* The QCM dosimetry analysis method was used to measure deposited mass and nicotine, enabling the comparison of these dosimetric parameters for both aerosols and providing context for the cytotoxicity assay results.
* The study highlights the potential of e-cigarettes as a safer alternative to cigarette smoking, with significantly less cytotoxicity observed in e-cigarette aerosol compared to tobacco smoke.

Main Message:
The study demonstrates the feasibility of using an adapted Borgwaldt RM20S exposure system and QCM dosimetry analysis method to compare the cytotoxicity of tobacco smoke and e-cigarette aerosol. The results show that e-cigarette aerosol is significantly less cytotoxic than tobacco smoke, providing further evidence for the relative safety of e-cigarettes compared to conventional cigarettes. This study could form the basis of a larger package of work including chemical analyses, in vitro toxicology tests, and clinical studies to help assess the safety of current and next generation nicotine and tobacco products.

Azzopardi, David, Kharishma Patel, Tomasz Jaunky, Simone Santopietro, Oscar M. Camacho, John McAughey, and Marianna Gaça. “Electronic Cigarette Aerosol Induces Significantly Less Cytotoxicity than Tobacco Smoke.” Toxicology Mechanisms and Methods 26, no. 6 (July 23, 2016): 477–91. https://doi.org/10.1080/15376516.2016.1217112.