Vaping, or electronic cigarette use, is becoming increasingly popular, particularly among young adults. While vaping is often portrayed as a less harmful alternative to smoking cigarettes, the act of inhaling aerosolized e-liquids exposes users to dangerous chemicals that can lead to adverse health effects. 

 

 

A popular bad habit

 

According to a joint study from the US FDA and the CDC, 2.55 million middle and high school students reported current e-cigarette use in 2022.

Cooper M, Park-Lee E, Ren C, et al. Notes from the Field: E-cigarette use among middle and high school students — United States, 2022. MMWR Morb Mortal Wkly Rep. 2022;71(40):1283–1285.

 

Among those who vaped, approximately 85% used flavored e-cigarettes. The most popular flavors were various fruits (69.1%), candy, desserts, or other sweets (38.3%), mint (29.4%), and menthol (26.6%). 

“This study shows that our nation’s youth continue to be enticed and hooked by an expanding variety of e-cigarette brands delivering flavored nicotine,” said Deirdre Lawrence Kittner, PhD, MPH, director of CDC’s Office on Smoking and Health, in the CDC’s press release about the study.

CDC. More than 2.5 million youth reported e-cigarette use in 2022 [press release]. October 6, 2022.

 

The most recent data from the National Health Interview Survey found that 4.5% of adults aged 18 years and older were current e-cigarette users, with vaping being highest among adults aged 18 to 24 (11.0%).

Kramarow EA, Elgaddal N. Current electronic cigarette use among adults aged 18 and over: United States, 2021. NCHS Data Brief, no. 475. July 2023.

 

 

Unique chemicals in flavored vapes

 

A 2024 study published in Scientific Reports utilized a machine learning approach to predict the degradation products formed when 180 known e-cigarette flavors undergo heating in a vaping device prior to inhalation.

Kishimoto A, Wu D, O’Shea DF. Forecasting vaping health risks through neural network model prediction of flavour pyrolysis reactions. Sci Rep. 2024;14(1):9591.

 

The authors note that there is an erroneous assumption that the flavor ingredients utilized in e-cigarettes are designated as “generally recognized as safe” (GRAS) according to health organizations. However, this status only applies to human consumption of these ingredients through ingestion and not through inhalation following heating. The health impacts of consuming these compounds via inhalation remains largely unknown. 

In an interview about the study, Donal O’Shea, MD, the study’s lead author, said, “We wanted to understand, before it’s too late, the likely impact flavored vapes are having on the health of the growing number of vapers. Our findings indicate a significantly different profile of chemical hazards compared to what we are familiar with from traditional tobacco smoking.”

RCSI. Researchers warn of toxic chemicals in popular vape flavors. SciTechDaily. May 24, 2024.

 

It is plausible that we are on the cusp of a new wave of chronic diseases that will emerge 15 to 20 years from now due to these exposures.

“We hope this research will help people make more informed choices and contribute to the conversation on the potential long-term health risks and the regulation of vaping, which this research suggests should be comprehensive,” Dr. O’Shea concluded.

RCSI. Researchers warn of toxic chemicals in popular vape flavors. SciTechDaily. May 24, 2024.

 

 

Impact on oral flora 

 

Cigarette smoking has long been shown to seriously impact the oral microbiota of smokers, disrupting the balance between microbes present in the oral cavity. However, studies investigating the impact of e-cigarettes on the oral microbiota have been limited.

Authors publishing in Frontiers in Physiology compared the effects of flavorless vs flavored e-cigarette-generated aerosols on the growth of four common bacterial strains found in the oral cavity (Streptococcus gordonii, Streptococcus intermedius, Streptococcus mitis, and Streptococcus oralis).

Fischman JS, Sista S, Lee DK, et al. Flavorless vs. flavored electronic cigarette-generated aerosol and e-liquid on the growth of common oral commensal streptococci. Front Physiol. 2020;11:585416.

 

 

 

Discussions with patients

 

In a recent cross-sectional survey of 2,058 physicians, 70% of physicians reported that they were asked about e-cigarettes by their patients; 1 out of 3 physicians had been asked in the past 30 days.

Delnevo CD, Jeong M, Teotia A, et al. Communication between US physicians and patients regarding electronic cigarette use. JAMA Netw Open. 2022;5(4):e226692.

Pulmonologists and primary care physicians were more likely to be approached by patients about vaping, whereas oncologists were least likely. 

 

According to the study, 22% of physicians who completed the survey reported that they recommended e-cigarettes in the past. Physicians were more likely to recommend e-cigarettes for older, heavy smokers with previous unsuccessful attempts to quit smoking than for younger, lighter smokers with no previous attempts at smoking cessation.