Scientists warn this is the worst, most toxic e-cigarette flavour for you

Although many of the flavourings used in e-cigarette liquids have been certified as safe for eating, little is known about their effects when heated and inhaled in e-cigarettes.

Several flavourings added to electronic cigarettes significantly affect the toxicity of the devices, with strawberry flavour being the most toxic to users, a new study has warned.

Researchers from Roswell Park Cancer Institute in the US also confirmed an earlier finding that increasing the battery output voltage of these devices significantly increases toxicity.

“Although many of the flavourings used in e-cigarette liquids have been certified as safe for eating, little is known about their effects when heated and inhaled in e-cigarettes,” said Maciej Goniewicz, Assistant Professor at Roswell Park.

“This study suggests that various characteristics of e-cigarettes, including any flavourings, may induce inhalation toxicity and therefore, caution should be used with these products until more comprehensive studies are performed,” said Goniewicz.

In the study, researchers exposed bronchial cells to aerosol generated from several variable-voltage e-cigarettes. They analysed cell viability and activity as well as the release of inflammatory mediators.

They evaluated six types of e-cigarette devices filled with liquids of different flavors - tobacco, pina colada, menthol, coffee and strawberry - at several battery output voltages.

Their findings suggest that the power of the e-cigarette device, as well as the addition of any flavourings, significantly affect the toxicity of e-cigarette aerosol, with strawberry flavourings being the most toxic to users.

“Our study demonstrates that e-cigarette products differ significantly in the degree of their cellular toxicity to bronchial epithelial cells,” said Goniewicz.

“These findings have important regulatory implications, because the features of e-cigarette products - such as the power of the device and the presence of flavourings - can be regulated and standardised,” he said.

“Additionally, users may want to reduce their potential harm by choosing products with lower toxicity profile and operating their devices at lower power settings,” Goniewicz added.

The study appears in the journal Tobacco Control.