Electronic Cigarettes Part VII: Vapor Analysis – How we sampled for VOCs like formaldehyde

If you have been following this blog series, then you already know that we found numerous (upwards of 64) compounds in electronic cigarette solutions. You also know that we found even more (approximately 82) compounds in e-cigarette vapor. More importantly, you know not to waste your time testing the e-juice, because the vaporization process found in e-cigs results in a vapor with a different chemical profile than the liquid; and results in the production of toxic/carcinogenic VOCs like formaldehyde. What you do not know is how we have been testing our e-cigarette vapor. So without further ado I introduce to you our simple sampling device for collecting electronic cigarette vapor:

So what do we have here? We have an electronic cigarette connected to a thermal desorption (TD) tube and the other end of the TD tube connected to a 50 mL gas tight syringe. To collect a vapor sample from the e-cigarette we simply pull on the gas tight syringe, thereby drawing the e-cig vapor across the TD tube for collection. Subsequent to sampling we place the TD tube in our Markes UNITY for thermal extraction. So there it is in short form.

Now for those of you who like details continue reading on. The TD tube we chose for our work consists of the following 3 sorbents: Tenax TA, Carbograph 1TD, and Carboxen 1003. We chose this tube for its ability to look at C2 to C32 compounds, thus giving us our best chance of seeing as many VOCs and SVOCs. We chose the 50 mL gas tight syringe, because we already knew from the peer reviewed literature that a standard e-cig puff was anywhere from 35 to 70 mL (we chose 40 mL for the record). Lastly, it is important to note that the peer reviewed literature suggested that e-cig vaping topography was usually a puff over a ~4 second period. So obviously we drew our puffs over ~4 seconds. One last important point… the LED lit on the e-cigs when we drew on the syringe, indicating that vaporization was taking place. This is a very important point, because… well… you already know now.

Next time we can cover more on our vapor sampling methodology, compounds of interest, concentrations, and implications.