Don’t Heat Your E-Cigarette! — Chromatography Investigates

E-cigarettes are promoted as smoking’s healthy option. Currently vaping seems to be caught between being accepted and being categorized with smoking. Some places seem to allow vaping and others prohibit it — with non-users seemingly forced to breathe in whatever is in the clouds generated by users.

But it should be remembered that e-cigarettes and vaping are still relatively new, the technology has not been fully tested and regulations have not kept up with the rapidly expanding market. E-cigarettes are essentially unregulated when we consider the vapours they produce and the chemicals in the fumes we have to breathe.

Chromatography has the measure of e-cigarettes

A new study by researchers from the Lawrence Berkeley National Laboratory and published in Environmental Science & Technology — Emissions from Electronic Cigarettes: Key Parameters Affecting the Release of Harmful Chemicals — has looked at the emissions from e-cigarettes and also how factors like temperature and type of device affect the emissions from the devices.

The team simulated ‘vaping’ using two different vaporizers with different types of e-liquids and power settings. The e-cigarettes used were different models — one had one heating coil and the other had two heating coils in parallel. The team used a variable power supply to control the power going to each of the vaporizers — as some vaporizers allow users to control the voltage they use to affect the ‘hit’ they get.

Headspace gas chromatography in tandem with mass spectrometry (HS-GC/MS) and high pressure liquid chromatography (HPLC) was used by the team to analyse the constituents of the e-liquids (the liquid vaporized in the cigarette) that were used.

Analysis of the vapours generated by the vaporizers was carried out using thermal desorption gas chromatography with mass spectrometry (TD-GC/MS). The use of TD-GC is extensively discussed in the article, The Benefits of Thermal Desorption Coupled with Gas Chromatography for the Analysis of Hydrocarbon Residues in Liquefied Petroleum Gas.

Analysing the vaping factors

The team’s results show how the emissions from e-cigarettes change with the different factors and with age. Both devices showed increasing temperature profiles with use — with the devices reaching steady-state after 20 puffs or 10-20 minutes. They found that the emissions increased by a factor of 10 as the temperatures increased until steady state was reached.

One of the substances emitted — acrolein, a severe eye and respiratory irritant — was found at levels of 0.46micrograms per puff at the start, but increased to 8.7 micrograms per puff at steady state — still lower than a conventional cigarette. The double coil device had lower emissions than the single coil e-cigarette — the researchers suggest this could be due to lower temperatures in the coils.

One of the main findings by the team was the presence of propylene glycol and glycidol in the vapour of e-cigarettes — the first time that these probable carcinogens have been found in the vapour of e-cigarettes.

The findings show that we don’t know what effect e-cigarette might have on human health — both for the users and non-users.