Tobacco-Specific Nitrosamines in Electronic Cigarettes: Comparison between Liquid and aerosol Levels

Introduction:
This text is a summary of a scientific study that compares the levels of tobacco-specific nitrosamines (TSNas) in electronic cigarette (EC) liquids and the respective aerosol. The study aims to determine whether TSNas levels in the EC aerosol exceed the levels present in the liquids.

Key Points:

* The study analyzed three commercially-available EC liquids of tobacco flavor and one spiked sample, prepared by adding a known amount of TSNas standard solutions to one of the commercial liquids.
* The liquids were analyzed for N-nitros onornicotine (NNN), N-nitros oanatabine (NaT), N-nitrosoanabasine (NaB), and 4-(methylnitrosamino)1-(3-pyridyl)-1-butanone (NNK) using ultra-performance liquid chromatography and tandem mass spectrometry.
* Three sets of 100 puffs were collected from each EC liquid, and the aerosol from each set was trapped and analyzed similarly to the method used for liquid analysis.
* The spiked sample contained measurable amounts of all four TSNas, while minimal levels of nitrosamines were found in the liquid samples.
* The 100-puff sets of commercial liquids resulted in an average liquid consumption ranging from 336 to 515 mg for each of the liquid. however, due to the very low levels of TSNas in the commercial liquids, the respective aerosol samples contained no TSNas above the LOD.
* The analysis of the aerosol generated from the spiked sample showed that all TSNas were detected in the aerosol, at levels that were not statistically different from the expected amounts.
* a strong correlation between expected and measured amounts of TSNas was observed (r = 0.83, p < 0.001).

Main Message:
The main message of the study is that the levels of TSNas in the EC aerosol are similar to those present in the liquid. Therefore, the analysis of TSNas levels in the liquid would be enough to estimate the exposure of consumers to these substances, without the need to perform more complex and expensive analyses in the aerosol. The study also confirms that the use of pharmaceutical grade nicotine will probably ensure minimal exposure of consumers to TSNas from EC use.

Farsalinos, Konstantinos, Gene Gillman, Konstantinos Poulas, and Vassilis Voudris. “Tobacco-Specific Nitrosamines in Electronic Cigarettes: Comparison between Liquid and aerosol Levels.” International Journal of Environmental Research and Public health 12, no. 8 (July 31, 2015): 9046–53. https://doi.org/10.3390/ijerph120809046.