Επικίνδυνα υγρά 100mg που στην πραγματικότητα ήταν 272 mg
Just to bring people back up to speed with this issue, several people here suspected that their Box Elder unflavored nic was too high compared to the labeled concentration. Someone claimed to have tested that theirs was 240 mg/mL. Others stated that theirs was also strangely strong. I, on the other hand, suspected mine was just different somehow, since it had no TH and very little odor in the 100 mg VG I bought. I offered to run full titration pH-curve analysis on any nic that was sent to me, since I was interested in nic level as well as freebase/nic-salt ratio. Several sent me samples of theirs, and I am presenting the results here, after spending much of the day doing these as accurately as possible.
At some point during the discussions, BE decided to send an email out to all its customers stating that it was impossible for anyone to receive >200 mg nic, and people should be assured that whatever the nic level was that was ordered, that was the nic level received.
Titration curves are not difficult to obtain, but to do them accurately requires specialized glassware and electronics. In my 30 year career I have done 1000s of such titrations.
What I did: I used a PASCO pH probe calibrated to within 0.001 pH points at buffer pHs of 4, 7, and 10. I also used a calibrated PASCO drop counter, allowing accuracy to within about 1/30th of a mL during the titration. I used volumetric pipets and volumetric flasks to make dilutions for the nic liquids to be titrated, and I titrated with standardized 0.0730M HCl. pH at 0 mL titrant was measured to estimate freebase/salt ratio, and pH curve was created to past the first equivalence point (2nd inflection point). Each nic sample sent to me was titrated 3 times at least, and most samples sent were enough to do another set of 3 titrations. The nic concentration was then calculated from the titrant volume at the first equivalence point, back calculating to the original sample concentration.
All samples, including my own sample, were virtually all freebase form, base on initial pH and final nic content found.
I will give the results in two columns. The first is the nic content as given on the label. Second column will be the nic conc as determined by the above method.
Nic labeled.....Nic determined
100 mg....48 mg (This one was mine. Thanks BE.)
100 mg....121 mg
100 mg....272 mg
48 mg....78 mg
36 mg....51 mg
48 mg....59 mg
100 mg....98 mg (this was my MFS 100 mg VG)
I would say the intrinsic error is less than 2% for all of these. These results are as accurate as is obtainable, IMHO. I knew the one that gave the result of 272 mg was way high when I opened it, as it was so strong in nic odor that I had to work with it in a fume hood for the dilutions. It was also honey-amber, whereas the others were either colorless or slight yellow.
272 mg nic was likely the base they diluted to 100 mg from, or else they were mistakenly sent a lot of 100 mg nic that was actually 272 mg.
I don't give a rat's a$$ what their excuse is, someone could well have died from this! I am a seasoned chemist, and this liquid was seriously scary to work with. Clearly there is more concern with CYA than actually testing their nic. Had they been responsible and expressed concern and actually tested their nic, this might have been avoided, but they instead chose to lie and even condescend as to how ridiculous the idea of levels being sold wrong was, and how oh so professional they are.
For this community, this is about as bad as it can get. I strongly recommend Box Elder be banned from ECF, and the word should be spread to other ecig forums. The FDA would have a field day with this. If others want their nic analyzed, PM me.
Vendors, you are now on notice. Either self-regulate and KNOW what you are selling, quantitatively, or else you are putting people, as well as the industry itself, in grave danger. I have no problem buying small quantities of unflavored nic solely for testing purposes. You have been warned.
I am seriously outraged by this.
http://www.e-cigarette-forum.com/forum/diy-e-liquid/239728-houston-we-have-problem-nic-titration-results.html
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