Toxic Chemical Additives in E-Cigarette Flavorings: New Study

We have reported on this topic in the past and now a new scientific study has confirmed that the chemical additives contained in the flavorings for e-cigarettes (vape) are toxic to the users.  What is still needed is research on ‘organic’ flavorings, including those that users make on their own, to determine whether heating and inhaling these organic substances causes similar adverse reactions.


E-cigarette flavors are toxic to white blood cells, warn scientists

A new study adds to growing evidence on the harmful health effects of e-cigarettes. The study finds that exposure to commonly used e-cigarette flavoring chemicals and liquids can cause significant inflammation to monocytes, a type of white blood cell. Moreover, many flavoring compounds are toxic, with cinnamon, vanilla and buttery flavors among the worst. It also finds that mixing e-cigarette flavors has a much worse effect than exposure to just one.

Vaping exposes the lungs to flavoring chemicals when the e-liquids are heated and inhaled. Since the flavoring chemicals are considered safe to eat, e-cigarettes are often considered — and advertised — as a healthier alternative to traditional cigarettes. However, the health effects of inhaling these chemicals are not well understood.


The study

This new study, led by researchers at the University of Rochester Medical Centre in the United States, wanted to test the assumption that vaping nicotine-free flavored e-liquids is safer than smoking conventional cigarettes. Previous studies show that flavors used in e-cigarettes cause inflammatory and oxidative stress responses in lung cells. Users of e-cigarettes also show increased levels oxidative stress markers in the blood compared to non-smokers. The new study extends this to assess the effects of commonly used flavoring chemicals, as well as e-liquids without nicotine, directly on immune cells — namely, a type of white blood cell called monocytes.


The results

Exposure to the e-cigarette flavoring chemicals and e-liquids led to higher production of two well-established biomarkers for inflammation and tissue damage mediated by oxidative stress. Furthermore, many of the flavoring chemicals caused significant cell death — with some flavors being more toxic than others.


“Cinnamon, vanilla and butter flavoring chemicals were the most toxic but our research showed that mixing flavors of e-liquids caused by far the most toxicity to white blood cells.”  -Dr. Thivanka Muthumalage, lead researcher


Journal Reference: Thivanka Muthumalage, Melanie Prinz, Kwadwo O. Ansah, Janice Gerloff, Isaac K. Sundar, Irfan Rahman. Inflammatory and Oxidative Responses Induced by Exposure to Commonly Used e-Cigarette Flavoring Chemicals and Flavored e-Liquids without Nicotine. Frontiers in Physiology, 2018; 8 DOI: 10.3389/fphys.2017.01130