Titled, “In Vitro And In Vivo Cardiac Toxicity Of Flavored Electronic Nicotine Delivery Systems,” the current aimed to determine the impact of flavouring chemicals on heart health, by exposing heart cells from mice to flavour additives in a lab environment.
“The flavored electronic nicotine delivery systems widely popular among teens and young adults are not harm-free,” said lead study author Dr. Sami Noujaim in a university release. “Altogether, our findings in the cells and mice indicate that vaping does interfere with the normal functioning of the heart and can potentially lead to cardiac rhythm disturbances.”
More specifically, reported the study, vanillin aldehyde flavoured e-liquids reduced the hERG current in transfected human embryonic kidney cells, while in mice, the inhalation of this flavour additive increased sympathetic predominance in heart rate variability measurements.
“Mice are not little people. No drug can get into the approval cycle at the US Food and Drug Administration if it only studied them or cells in dishes,” he added. Moreover, explained Campbell, the HL-1 cells from mice and later the lab produced human cells, were inundated with levels of vaping chemicals that a human body could not get exposed to in 40,000 years.
Meanwhile, another recent US study published in eNeuro, reported that a commonly used green apple e-liquid flavour, enhances the nicotine reward pathway in the brain. Conducted by researchers at Marshall University in West Virginia, the study found that the flavourant farnesene in green apple flavoured vaping products, triggers reward-related behavior by promoting high-sensitivity nAChRs in the ventral tegmental area of the brain. In simple terms, this means that this compound makes this flavour addictive.
“With or without nicotine, flavoured vapes pose potential risks for the brain and addiction,” said lead study author Skylar Cooper. Cooper, who is a research technician Austin Akers and her research team, split study subjects (mice) in 3 groups. One group was given nicotine, another the green apple flavourant farnesene or both, and the third a saline solution.