Electronic Cigarettes Part V: Vapor Analysis – Yes… we found formaldehyde too!

It has been over 3 months since the last electronic cigarette blog. I will spare you the excuses. However, I can proudly say that we will be releasing a full application note on electronic cigarettes in the very near future (i.e., 1 to 2 months hopefully). In the meantime I feel obliged to respond to all the various inquiries I have received from colleagues about the presence of formaldehyde in electronic cigarettes. Lately I hear things like “oh I just heard on NPR about formaldehyde in electronic cigarettes… is this true… did you know that?”  Well… obviously you already know my answer to this hot topic question. So allow me to indulge…

In parts I II III and IV of this blog series we covered analyzing the e-juice for nicotine and impurities. In the last e-cig blog we saw that electronic cigarette solutions contained numerous impurities. At that point in time we did not go into a lengthy discussion on what compounds were found and their potential implications for human health. Why you ask? Well because theoretically no one is drinking the e-juice… nor is anyone bathing in the e-liquid… and lastly I doubt anyone is injecting the e-solution. The main route of exposure to e-cigs and any compounds of interest is the direct result of the vaporization process, whereby with the use of a heated filament, the liquid is turned into a vapor which the end user inhales. Despite the aforementioned, the majority of e-cig research has focused on analyzing the e-juice. However, now that the knowledge of formaldehyde in the vapor has hit the mainstream media, perhaps that paradigm will change. FYI – Anyone interested in further reading or references should just reach out. Now… after much delay and teasing here is what we have seen in the e-cig vapor:

E-Cig Vapor A

I know… boring. So how about we zoom in:
E-Cig Vapor B

Based on the above chromatogram our e-cig vapor has a lot more constituents than the manufacturer’s juice listing of propylene glycol, glycerin, and nicotine. No surprise here, we already saw this trend when analyzing the raw solutions. NOTE: these vapor results are for the exact same e-juice results presented in our last e-cig blog. So what are all of these peaks? Well… the following table will hopefully help break down all the unknown compounds into several more digestible sections. Note: We only included tentative compounds with a mass spectral quality of 80% or greater according to the NIST 2005 database. Compounds with 100% quality have been confirmed with standards.

E-Cig Vapor Table A

We found 82 unidentified and identified (some only tentatively) compounds in the e-cigarette vapor for this manufacturer. Of particular interest was the presence of formaldehyde, acetaldehyde, acrolein, as well as several siloxanes. All of which we did not find in the raw e-juice. *In order to confirm the components we were seeing were not simply from the background air, we also collected and analyzed 40 mL samples of the background air just like the e-cig vapor. These samples are represented in the “blank” column in the above table.

So… what does this all mean? Oh… and how did we measure the vapor? This time I promise to come back sooner than three months to answer these questions.

4 Responses to “Electronic Cigarettes Part V: Vapor Analysis – Yes… we found formaldehyde too!”

  1. Shaun Marsh says:

    I just went through your blog and i found it quite useful. Recently it has been observed that electronic cigarettes have become quite popular among the youth and i guess it’s time to stop these unhealthy practises.

  2. AP says:

    Yes Shaun Marsh, and while you are at it, please stop breathing altogether since air contains impurities that can harm you!!!

    I would be interested to see your comparison of the air quality from which these tests were performed. The constituents you claim are from the vaporization of the e-juice may well be present in the air in the first place. Just because you found X constituent does not correlate to a harmful concentration unless compared to the indoor air quality in different situations and known concentrations of X deemed unsafe.

    I look forward to this extremely long and drawn out blog on the chemical make-up of electronic cigarette vapor and I sincerely hope you will not blow things out of proportion by making wild claims that because it contains ‘blahblah’ it is immediately harmful.

  3. Please excuse my oversight. The column labeled “blank” in the table of components we found represents exactly what you are interested in. I have fixed the blog accordingly. We already realized that the air drawn through an electronic cigarette is the background air and more often than not contains toxic VOCs. So we collected and analyzed 40 mL samples of the background air too. Formaldehyde, acetaldehyde, and acrolein (as well as most of the other VOCs) were not present in the background air.

    In regards to your comment on concentrations and health, please stay tuned.

  4. Yes e-cigarettes are also toxic as it contain nicotine in liquid form. You have shared very informative information in your blogs. The e-cigarettes are also harmful when smoker use in long term.

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