Mint flavor in vaping liquids associated with worsening lung function in e-cigarette users

According to researchers from the University of Pittsburgh in Respiratory research Today.

Using a specially designed robotic system that mimics the mechanics of human breathing and vaping behavior, researchers have shown that commercially available e-cigarette liquids containing menthol generate greater numbers of toxic microparticles than juice without menthol. A companion analysis of patient records from a cohort of e-cigarette smokers found that menthol vapers took shallower breaths and had lower lung function than non-menthol smokers, regardless of age, sex, race, number of years of smoking and nicotine use. or vaping products containing cannabis.

Many people, especially young people, mistakenly assume that vaping is safe, but even vaping mixes without nicotine contain many compounds that can damage the lungs. Just because something is safe to eat as food doesn’t mean it’s safe to inhale.”

Kambaz H. Benam, D.Phil., main author, Associate Professor in the Division of Pulmonary, Allergy, and Critical Care Medicine at the University of Pittsburgh School of Medicine

To steer young people away from vaping and reduce preventable deaths, the U.S. Food and Drug Administration continues to pressure cigarette manufacturers to remove menthol from combustible tobacco products, such as regular cigarettes and cigarettes. cigars. But the market for vaping products around the world continues to grow, and mint and menthol flavors remain hugely popular among the 2.5 million young people who reported smoking e-cigarettes in 2022.

Because traditional toxicity tests, which involve animals or live cells grown on a flat surface, can take weeks or months to produce high-quality, clinically relevant data, regulators are struggling to keep up. and timely product safety testing.

Traditional approaches also have other limitations. Mice and rats, animals primarily used to test the safety and biological impact of aerosol products, have a very different anatomy of their nasal passages compared to humans, which prevents them from actively breathing through their mouths, which which resembles a puff of a cigarette. And the cell systems used for toxicity testing are either directly exposed to e-liquid on contact or blasted with continuous aerosols that disregard human breathing patterns.

To improve preclinical testing of the impact of mixing vaping liquids and adding flavors on vapor composition and its health effects, researchers developed a biologically inspired “vaping robot” . By accurately mimicking temperature, humidity, puff volume and duration, this machine can simulate the pattern of healthy and diseased breathing and reliably predict e-cigarette-related lung toxicity.

The system can measure the size and number of aerosolized particles generated and how these parameters vary with liquid composition. Aerosol effects can then be tested on engineered “lung-on-a-chip” devices and quickly provide high-quality data that can be used to infer potential toxicity.

In their previous research, Benam and his team found that vitamin E acetate, a common additive in e-cigarette liquids containing cannabinoids, generates more small toxic particles that can travel deep inside the lungs and stuck in the narrowest airways and mucosa. walls of the trachea and bronchi.

Although future large-scale clinical studies are needed, the new study suggests that menthol additives may be just as dangerous as vitamin E acetate, which was strongly linked to lung damage in e-cigarette and vape users. .

“The main message we want to get across is for people, especially young adults, who have never smoked,” Benam said. “Switching to e-cigarettes may be a better and safer alternative for someone trying to quit smoking regular tobacco products. But it is important to have a full knowledge of the risks and benefits of e-cigarettes before to try them.”

The study’s other authors are Divay Chandra, Ph.D., and Rachel Bogdanoff, Ph.D., both pitt; and Russell Bowler, Ph.D., of National Jewish Health, Denver.