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:
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.
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.
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.