How much nicotine is destroyed during vaping ?

[exogenesis]

Thank for reposting the link in the right place TV

I think TV first mentioned the pH regulating effect of saliva,
presumably that does have a significant role to play.

What we need then is 100 people, get them to vape, smoke or snus,
then at intervals remove a section of gum or cheek tissue & analyse for nicotine.
Volunteers?

 

[DVap]

How'd I miss this latest series of posts?

I gave up on the exhalation experiments before I even started with them since I knew CO2 would be a huge problem. Thanks to Exo for plowing ahead with trying to circumvent the difficulties.

Exo, have you considered blanking the CO2 via exhaling n breaths without vapor and titrating the CO2 on it's own to get a concentration?

 

[exogenesis]

Hiya DVap, was hoping you'd come in with some chemistry help

Sort of got a bit of 100yd-stare after 5 hours solid vaping into the trap
& still getting a questionable result

Was going to let it go for a while, at least until I get a bigger vapour trap
(double exhale volume) set up.

That idea did occur to me, but I thought possibly (probable?) that
the free-base nic in solution would tend to adsorb a lot more CO2
than just the water (in breath) does.

As far as I understand it: CO2 dissolves in water, reducing the pH,
amount dissolved is totally dependent on partial CO2 pressure :
at 5% like in breath it should amount to 2.5x10-5 molar HCO3- in solution = pH 4.6
Hence why acidifying & bubbling air through should work.

With a higher pH adorbant/buffer present though, the CO2 might continue
to dissolve until pH 4.6 was reached, ie having completely titrated the
free base nicotine (it's a good theory ).
Or maybe equilibrium would be somewhere in-between these amounts of CO2 dissolved?

Either way I think I'd get the wrong result ?

Maybe precipitation would work after all...

 

[exogenesis]

Another result:

36 mg/ml PG, at 6V (5.8 at atty), current 1.61 amps
Flow 3 to 3.3 ml/hr (very 'wet' & gurgling).
9.57 ml vaped & collected over around 3 hours.
Slightly cloudy beige coloured liquid collected, smelling of toast.

Titre 351.5 mg nicotine, very clean shaped curve.

= 102% nicotine recovery.
(obviously some experimental error there, but 2% is pretty good I think).
So high voltage vaping, at least with PG & coil kept very wet has
the least nicotine destruction, surprise!

This was with a brand new atty (3.3 ohm 901).
Got quite hot, even though I had a fan blowing over it,
could just touch it with my tongue for about 2 seconds before 'ouch'.

Tried 'dry' 6V vaping, with same atty & 2/3rd of the juice flow rate,
= bright orange coil (I can see the glow through the tubing),
when juice hits sometimes got a flame shooting up (!).

Unfortunately after about 5 minutes the coil blew, damn.

Must summarise the results so far & put into original post.

 

[TWISTED VICTOR]

= 102% nicotine recovery.
(obviously some experimental error there, but 2% is pretty good I think).
So high voltage vaping, at least with PG & coil kept very wet has
the least nicotine destruction, surprise!

"Surprise" is an understatement. And all those years I spent preaching the evils of high voltage on nicotine .

 

[exogenesis]

practice what you preach & thou shalt come a cropper

I thought the same way, but there's other apects to 6v vaping I fancy,
like having to drop the mg/ml to compensate for the significantly increased
vapour intake - or these 'high voltage' atties, which seem a bit odd
to me, i.e. up the wattage, only to reduce it again with a higher resistance coil

 

[Mister]

= 102% nicotine recovery.

You've found a way to synthesize nicotine!

Seriously though the high recovery at 6V is quite a surprise. Very interesting.

 

[DVap]

::face-palm::

Boil the solution... goodbye CO2.
(and goodbye O2, and goodbye bicarbonates.. well carbonates get left).

 

[exogenesis]

OK, maybe that's worth a try.

Is nicotine chemically stable with boiling at all pH's,
think it is with mild alkali, but also in acid when ionised ?


Re-reading the 'nicotine/water azeotope at 25mg/ml' links & others:
I'm guessing in dilute solution, nicotine would be lost with boiling,
(at least) proportionally with the water.
Would PG being present increase or decrease the carry over of nicotine ?

The collected water/PG/nicotine was only approx. 3mg/ml nic & say 10% PG,
so if I lost 10% of the water during boiling, I'd lose at least 10% of the nicotine,
so I'd have to reflux I guess.

If carbonates were left, that'd still be a problem....probably.

 

[DVap]

OK, maybe that's worth a try.

Is nicotine chemically stable with boiling at all pH's,
think it is with mild alkali, but also in acid when ionised ?


Re-reading the 'nicotine/water azeotope at 25mg/ml' links & others:
I'm guessing in dilute solution, nicotine would be lost with boiling,
(at least) proportionally with the water.
Would PG being present increase or decrease the carry over of nicotine ?

The collected water/PG/nicotine was only approx. 3mg/ml nic & say 10% PG,
so if I lost 10% of the water during boiling, I'd lose at least 10% of the nicotine,
so I'd have to reflux I guess.

If carbonates were left, that'd still be a problem....probably.

For carbonates to be a problem, you'd have to have bicarbonates in the first place. I'm not sure there would have to be any exhaustive boiling...We've all seen the pre-boil oxygen being purged (all those small bubbles forming). Test with some worst case carbonated water? Bring it just to boil and see if any CO2 is left?

 

[Vaporer]

I've never understood how the atty coil lives long at 6v. Yet , you dont read much of people complaining abt a high atty loss. Unless they've come to expect it.
Well you've proved that at 3.7v not all the nic is being vaporized. It may be cool enough that its slipping by due to draw force or is allowed to condense in the atty/cart area.
I've seen condensate in my 3.7v units alot.
The higher heat as you described seems to be letting nothing past without being vaporized. I've not seen higher ohm attys for HV users, but it seems that if that were the case, you will have less heat from the higher resistance, forcing yourself back towards the 3.7v scenerio. 5v users may have the "happy medium". Still more heat and power is drawn towards bigger batteries or shorter stock battery life(usage time) and a shorter lifespan would be expected.

You seem to be on both ends of the usage/efficiency scale. Not only with attys, but with nic concentration needed and recovery available.

Very interesting data exo.

 

[DVap]

I feel like I should say thanks again to Exo for the excellent work. I left the topic of nicotine recovery from vaping in a rudimentary and obviously imperfect state (46%), but Exo has run it to ground with a robust methodology that is both efficient and reproducible.

His results are nothing short of enlightening, and his equipment provides a fine platform to pursue the nicotine exhalation question.

And back to the exhalation studies...

Exo, the more I think about it, the more I like your idea of a fairly exhaustive boil with reflux. To validate integrity, a test solution of a known concentration of nicotine in water could be refluxed for 30 minutes (probably overkill), and tested for nicotine after reflux. If the result is consistent with the test concentration, then a similar reflux with trapped exhalent should provide a good result for nicotine with CO2 pretty effectively purged.

 

[TWISTED VICTOR]

Ah, good...appears we're on the move again. Happy to see you weighing in DVap. Eyes like a hawk, I say.

 

[exogenesis]

I've think that custom HV 6v attys have a higher resistance,
(e.g. EastMall 'HV' series 901/510/801 atties are all 4.5 ohm
but marked 'not for 3.7 or 7.4 V vaping').

Definately it appears to be the case with 5/6V & normal atties of needing
to keep them 'wet', or they will blow pretty quickly.


Another test result:
36mg/ml PG, 510 atty at 4V (3.8V at atty under load , 1.71 amps),
juice flow 2.8 ml/hour with '5 sec draw / 7.5 sec cool & settle' cycle:
got 101% recovery of 'nicotine'
(calculate 6.7 watts, c.f. 9.3 watts in the 6V 901 test & 3.3 watts
for 3.7V 901 tests)


Got another test running overnight: same atty & set-up but reduced to 1/3rd flow
(0.9 ml/hour), which causes coil to glow mediumly bright orange during vaping,
coil seem to be surviving (so far), should be informative.


Not 100% sure anymore that the older 3.7V (<100%) recovery tests
with 70mg/ml juice are directly comparable anymore,
the better vapour-collector design came in for the 18mg/ml test (95% recovery).
The older results were 'corrected' by adding up losses to the bubblers,
& although it looked reasonable I can't be sure there weren't innacuracies.
Probably best to repeat them with the new setup to be sure (bubblers not needed anymore).

The 18mg/ml (95%) test is directly comparable,
so I'll do further lower mg/ml test to see if there's a trend.


You've hit upon something I've been observing there Vaporer,
condensation in the atty itself (or tubes close to it),
it's certainly not insignificant and may be causing a bit of 'reflux' in these tests.

 

[exogenesis]

Cheers DVap, certainly I wouldn't have got started without your initial info
& nic. determination method.

I think further exhale tests will be on a larger volume collector setup,
and after having squished the CO2 problem.

OK that test sounds like a good place to gain confidence of not losing
nic. to boiling.
I'll have to get a small quick-fit conical flask & condenser,
plus get a cool water circulation sorted out
(maybe I can find a use for those peltier devices I got after all )

Might try an intermediate test, which would be to bubble breath into
a known nic. solution & reflux & test, to make sure its OK before
starting another vape/exhale marathon.

 

[exogenesis]

At the risk of a bit of multi-posting:


Result of harshest workable test I think I can do:

'dry-vaping' 510 atty, a bit of a problem,
5kV shorted some time during the night, so this result is for
the amount of 'nicotine' in a known amount of the condensed vapour liquor,
(rather than total collection).

36mg/ml nic. PG, 510 atty, 4.2V (3.8V, 1.71 amps under load at atty),
0.9 ml/hr = about 1/3 of that needed to keep coil 'wet & vaping nicely'.
Coil glows orange during vaping

Deep amber colour but very clear collected liquid,
(surprisingly, up to now it's been straw colour & slightly cloudy),

8.2 ml contained 269mg 'nicotine' = 32.8 mg/ml = 91% of juice nic. concentration.


Not sure at this point if what I titrated was actually all nicotine, or
substantially oxide or something similar - no way for me to tell.
Still had a fairly typical 'nicotine titration curve' shape

But certainly whatever it is, it doesn't get (very) significantly %age-wise combusted
or solidified on the coil, even under these extreme(?) conditions.

Then again if the missing nic. was all deposited on the coil as 'carbon',
it'd be ~30mg, which would be a very visible black coating
(presumably along with the hard thin black coating known to come from PG itself).


Fixing the collector ready for a marathon 50ml of 6mg/ml nic. PG run,
after that it'd be looking at exhale testing I guess

 

[Mister]

Result of harshest workable test I think I can do ... 91% of juice nic. concentration.

Cool, you finally managed to lose some! Your tests have shown it to be remarkably durable in the vaping process.

 

[Vaporer]

Not being an HV user or a real supporter of it I have not tried to keep up with thier equipment. Oddly enough my approach has bee exactly the opposite. How low on power can you go and still get sufficient vapor? I have a 4.5ohm coil I made and use which has been running for a long time now. 5 ohms showed a significant vapor production drop off at 3.7v. Your tests would indicate that this is not the most efficient usage of the eliquid for nic delivery, even though decent vapor is still being produced. The 510's that are using the 2.3ohm coil, not the 3.2ohm, would be closer to "stock" HV usage due to the higher heat they will produce from the lower resistance.

The PV is really still in its infancy. A 4.5ohm HV atty has much less space to heat in a 510 or 901 than an 801 which is almost 2x the dia and volume.
That comes down to a lot of testing to find the most efficient configuration before you hit the point of diminishing returns.

Nice work on your effort, testing and results

 

[exogenesis]

Yes Mister, looks like finally got some to be lost, but what is it that is coming
across in the harsh test, is it actually mostly nicotine, or an oxidation product?

Wish I had a method to find out - might try ion-exchange column
chromatography with a crude setup, would need a UV detector of some sort...


Interesting point Vaporer, I haven't tried 801 penstyle attys up to now,
I understand they are a bit more robust than 901 or 510 (at least by hearsay)
do they use a thicker wire?

Realistically the %age losses shown here are relatively insignificant compared
to the amount of vapour 'wasted' e.g. by exhaling while vaping.
I think we can now say effieciency is all in the vaping style.

Still would like to prove it is actually mostly nicotine,
in the bulk collected vapour, somehow.

 

[TWISTED VICTOR]

So far your results have been pretty consistant, exo. Says a lot. Looks like the actual nic % is becoming a thorn in your side, though.