As e-liquids gained popularity, the world said goodbye to that quintessential secondhand smoke smell. The vaping and e-cigarette industries have introduced flavored liquids, ranging from Blue Raspberry Cotton Candy to Frozen Lime Drop. But as a recent series of studies from the UNC School of Medicine suggests, there may be some toxic ingredients masked behind these enticing names.
Robert Tarran, an associate professor in cell biology and physiology, co-authored a study published in PLOS Biology on March 27 in which human cells were exposed to e-cigarette and vaping flavors. With funding from the FDA, Tarran and his team found that the levels of toxicity amongst the 148 ingredients that they studied varied greatly.
As the research project manager in the Tarran lab, Flori Sassano co-authored the study with Tarran. She said their team narrowed down which chemicals to study based on which e-liquids were popular at the time, but it was challenging to study the liquids since they had so many added chemical ingredients.
“The conclusion or take-home message was that these e-cigarettes are very heterogeneous,” Sassano said. “So it’s hard to make conclusions out of only one or two because the chemicals in them are very different.”
Off all of the ingredients, vanillin and cinnamaldehyde were found to demonstrate the greatest effects of toxicity. In order to evaluate the toxicity of each of the chemicals, Tarran recommended that the added flavors should be compared to the base compound, propylene glycol, which is found in nicotine.