A recent study suggests that flavouring added to the liquid nicotine burned in the devices may influence how much the fumes lead to health problems.
Researchers has tested vapour released by a variety of devices filled with some popular e-cigarette flavours (tobacco, pina colada, menthol, coffee and strawberry) to compare levels of chemicals known to case inflammation and cell damage. They also looked at how much these chemicals appeared in tobacco smoke and in smoke free air.
As we suggest it, the research shows that cigarette smoke was more toxic than fumes from e-cigarettes, said senior study author Maciej Goniewicz of Roswell Park Cancer Institute in Buffalo, New York.
E-cigarettes, however, had more toxic chemicals than smoke-free air, especially when the devices had higher power or voltage and when used with flavoured liquid nicotine.
“We found that strawberry-flavoured product was the most toxic among all liquids we tested,” Goniewicz added.
How the research was conducted?
The researchers exposed human lung cells in a dish to smoke, e-cigarette vapours and air. The cells reacted most strongly to smoke, by reducing their metabolic activity and increasing output of inflammation-related chemicals. Similar, but not as strong, reactions were seen with e-cigarette vapour, compared to no change with plain air.
Past research has found that higher-voltage e-cigarettes produce a bigger nicotine jolt, but may also increase levels of dangerous chemicals like formaldehyde.
“Our findings raise some concerns about the safety of additives used in e-cigarettes,” Goniewicz said.
“If an e-cigarette user experiences any side effects, for example cough or chest pain, he or she should consider changing the flavourings in the product and operating their device in lower-power settings.”
The current study doesn’t offer a complete picture of e-cigarette safety or address the potential for health problems to emerge after long-term use, the authors note.
But it does suggest flavours may have a big impact on safety.
Separate Study on E-Liquid
A separate study in the journal looked at cinnamaldehyde, a chemical added to liquid nicotine to create cinnamon flavours.
In lab tests of fluids from 39 refill cartridges of liquid nicotine, 20 contained enough cinnamaldehyde to damage cells, the study found. This included products labelled as cinnamon flavoured as well as a variety of sweet and fruity mixtures.
Here, too, the level of toxicity appeared greater with higher voltage devices.
“We previously showed that cinnamaldehyde was highly toxic when tested in vitro with various types of cells,” said senior study author Prue Talbot of the University of California, Riverside.
“In the new study, we further showed that cinnamaldehyde is much more widely distributed in e-cigarette products than originally thought and it appears in many sweet and fruity flavours, which are among the most popular,” Talbot added.