Electronic cigarettes and vaping: toxicological awareness is increasing.

Introduction:
This text is a summary of an editorial published in the Archives of Toxicology that discusses the increasing awareness of the toxicological problems associated with electronic cigarettes and vaping. The editorial highlights six contributions in the issue that approach the topic from various angles, including analytical chemistry, experimental toxicology, epidemiology, and clinical aspects. As an expert in regulatory matters, this summary will provide key points about the study designs and major findings of these contributions.

Key Points:

* Mallock et al. performed a chemical characterization of liquids and aerosols of American JUUL pod e-cigarettes. They found that the initial European version of JUUL pods did not compensate for the lower nicotine content in the liquid, but the modified European version did, resulting in similar nicotine delivery per puff as the American original.
* Ho et al. conducted subchronic inhalation toxicity studies of aerosols from flavored e-liquids and found that the inhalation of an e-liquid containing the neat mixture of "flavor group representatives" caused minimal local and systemic toxic effects. The biological effects were mainly nicotine-mediated.
* Chen et al. studied the effects of e-cigarette vapor extract on human monocyte-derived dendritic cells in vitro and found that the overall expression of 29 signaling molecules and other cytoplasmic proteins was significantly upregulated.
* Reumann et al. studied the effects of e-vapor aerosols and cigarette smoke on bone morphology, structure, and strength in a 6-month inhalation study and found that e-vapor products could potentially constitute less harmful alternatives to cigarettes in situations where bone health is of importance.
* Feldman et al. applied the Bradford-Hill causation criteria to vitamin E acetate and the EVALI outbreak and highlighted the need for systematized approaches to identify the cause of mass poisoning events of unknown etiology.
* Javelle suggested that recent clinical evidence of pulmonary toxicity caused by vaping could interfere with disease symptoms of the respiratory system caused by the recent COVID-19 epidemic.

Main Message:
This editorial and its six contributions highlight the complex questions associated with the assessment and management of risks of e-cigarettes and vaping products. The key points emphasize the importance of multidisciplinary approaches to understand the toxicological and biological effects of e-cigarettes fully. The findings suggest that while e-cigarettes may be less harmful than traditional cigarettes, they still pose potential health risks. Therefore, it is crucial to continue research and regulation efforts to ensure the safety and public health.

Bolt HM. Electronic cigarettes and vaping: toxicological awareness is increasing. Archives of toxicology. 2020;94(6):1783-1785. doi:10.1007/s00204-020-02786-3