Optimization of aqueous aerosol extract (aqE) generation from e-cigarettes and tobacco heating products for in vitro cytotoxicity testing.

Introduction:
This text provides an in-depth analysis of the cytotoxic response of human umbilical vein endothelial cells (hUVECs) to aqueous aerosol extracts (aqEs) from conventional cigarettes, tobacco heating products (ThPs), and electronic cigarettes (e-cigarettes). The study compares the cytotoxicity potential of these products and highlights the importance of a standardized aqE generation method and chemical characterization for toxicological assessment.

Key Points:

* The study used a standardized aqE generation method for all products, including 8 puffs for cigarettes, 40 puffs for ThPs, and 200 puffs for e-cigarettes.
* aqEs were chemically characterized for nicotine, propylene glycol (PG), and vegetable glycerol (VG) content.
* Osmolality measurements were performed to ensure physiological relevance and prevent osmotic stress.
* The cigarette aqE caused a maximum 100 ± 0.00 % reduction in cell viability, while ThP and e-cigarette aqEs showed varying levels of cytotoxicity.
* The aqE of the remaining e-cigarettes either resulted in an incomplete dose-response or did not elicit any response.
* The methods utilized were sensitive enough to differentiate between cigarette, ThP, and e-cigarette aerosols and distinguish between products within each product category.
* The study emphasizes the need for a standardized aqE generation method and chemical characterization to ensure reproducibility and accurate toxicological assessment.

Main Message:
The text underscores the importance of a standardized aqE generation method and chemical characterization for toxicological assessment of tobacco and nicotine products. By employing a consistent approach, researchers can better compare cytotoxicity potential across different products and ensure the accurate interpretation of results. This information can aid in the development of safer alternatives to conventional cigarettes and contribute to tobacco harm reduction efforts.

Bozhilova S, Baxter a, Bishop E, et al. Optimization of aqueous aerosol extract (aqE) generation from e-cigarettes and tobacco heating products for in vitro cytotoxicity testing. Toxicol Lett. 2020;335:51-63. doi:10.1016/j.toxlet.2020.10.005