Vapers, Beware: Cherry-Flavored E-Cigarettes Can Be Toxic

If you must vape, then choose your e-cigarette liquid wisely. REUTERS/Neil Hall

Many people claim e-cigarettes are a less harmful option than conventional cigarettes. But research suggests that may depend on which flavor you choose.

A new study published in Thorax suggests vapers should select their e-cigarette liquid with an abundance of caution, since some contain especially high levels of benzaldehydes. While the chemical is frequently used as flavoring in many food products, it can be toxic when inhaled and is a strong irritant to the respiratory system.

"As e-cigarette popularity increases, respiratory clinicians need to be aware of potential risks that may result from use," the researchers write in the study. "Although e-cigarettes may be a promising harm reduction tool for smokers, findings indicate that using these products could result in repeated inhalation of benzaldehyde, with long-term users risking regular exposure to the substance."

For the study, the researchers conducted safety tests on 145 different e-cigarette liquids of various flavors, including tropical, berry, tobacco, alcohol, chocolate and candy, coffee and tea, menthol and cherry. They measured levels of benzaldehydes by creating aerosol vapors with an automatic smoking simulator and tested 30 puffs of each. They then calculated the levels of benzaldehydes for 163 puffs—the estimated number taken by a vaper per day. These figures were also compared to levels of the toxic chemical in the same number of puffs taken from a regular cigarette.

The researchers detected high levels of benzaldehydes in 108 out of 145 e-cigarette vapors—74 percent of the samples. They found the highest levels of the chemical in the cherry-flavored product, as much as 45 times higher than levels found in many other e-cigarette liquids they tested. Even more, 30 puffs of cherry-flavored e-cigarette liquid contained benzaldehyde levels that were higher than regular cigarettes.

E-cigarette liquids with chocolate, candy, coffee, tea and tobacco flavoring also had high benzaldehyde levels—though not as high as the cherry-flavored liquid. Fruit flavors (other than cherry) and those formulated to taste like alcohol or other beverages had the lowest levels of the chemical.

Though the study is based on a simulation of vaping and may not reflect the actual levels of benzaldehyde with perfect accuracy, the findings do suggest that cherry-flavored e-cigarette liquid poses a particular danger. The researchers also say consumers should be made aware that many of the e-cigarette products currently on the market contain levels of benzaldehyde that can potentially be toxic.