hifistud:
By the rules that you suggest, no "unflawed" study is possible. Once the cartridge contents are analyzed for nicotine content, they cannot be inhaled. Once the vapor is analyzed for nicotine content, it cannot be inhaled.
If I analyzed 20 cartridges labeled "16 mg" and found 16 mg nicotine in each, and then repeated my study with a 21st cartridge and found no nicotine in participants' blood, you could as easily say there was no nicotine in that 21st cartridge.
With respect, this demonstrates your lack of understanding of the system.
Consider the following methodology:
1 take a 50ml sample of, say, 24mg labelled e-
juice and a selection of, say, 20 atomisers and 20 batteries.
2. Assay a sample of 1ml of the 50ml of e-juice for nicotine content to confirm its concentration.
3 measure each atomiser for resistance - discard any which are more than 0.1ohms from the average value.
4 Fully charge each battery, and measure its output under load from ONE selected atomiser. Discard all which are more than 0.1 volts away from the average.
5 for each participant, fill each cartridge with a known measured amount of
e-liquid (its "designed capacity") from the 50ml assayed sample and perform ten, measured, mechanical draws taking, say, 5 seconds per draw, each to fill a 60ml syringe before the subject uses the cart.
6 Assay the mist collected in each numbered syringe for nicotine content, and note any increase/decrease with sequential draws (puffs).
and then continue as before...
Would other methods lead to different results? Perhaps they would, perhaps they would not. That is why we conduct studies. Until we conduct studies, we can only act on faith/belief.
Again, with respect, it would have helped had you understood the variability of the equipment with which you sought to work, and how an electronic cigarette atomiser is packaged and delivered. Had you known that there is enough non-nicotine bearing primer fluid already extant in each atomiser to provide over 20 short "puffs", you may have approached your methodology differently. A regular and experienced user, however, could have advised you that each atomiser needs "breaking in" and the primer fluid exhausted before the atomiser will work as designed.
Similarly, e-cigarette usage requires a different "puffing" technique - longer, slower and more measured than a tobacco cigarette. Were your subjects instructed accordingly?
I am well acquainted with the symptoms of an over-indulgence of nicotine, and can tell you that the e-cigarettes I use most definitely deliver nicotine, admittedly in smaller acute quantities than cigarettes, but on a par with both gums and lozenges over time.
I have no objection to your choice to use an e-cigarette because you have faith/believe that it does something.
My interest is in verifying what it does.
As is mine, and I am here to advise you that your method, unfortunately, does not in any way produce reliable results. Before you can measure the nicotine absorbed into the body, you must first confirm that there is nicotine in every stage of the system. This, I'm afraid, you have failed to do - the cartridges could have been filled with distilled water, for all you know. The atomisers may have failed mid-puff - there are no data on exhaled vapour, nor even mention of it. In short, the data you have produced tell us nothing, and are unreliable.
I do want to tell you, though, that none of the above is meant as a personal attack on you, in any way. I believe that you have undertaken the study in good faith, but, I am afraid, from a standpoint of unwitting ignorance of the system under test.
