New studies find carcinogens in vg and pg at high temps, even in tootle puffers

[zoiDman]

Its not being circulated, it's also a very thin layer of liquid at the coil in most cases. It's not as if the coil is submerged in a tank of liquid.

Yeah... If one wants to use the Car analogy, a Better one would be a Car that has a Broken Water Pump Belt.

Where the water is just kinda sitting there. And the Water that is Vaporized is replace by the Adjacent Water. And possible Film Boiling is Occurring.

Because Film Boiling doesn't occur under all Circumstances when a Liquid is in Contact with a Heat Source.

 

[mikepetro]

I think my brain is boiled at this point.

 

[CMD-Ky]

Leidenfrost effect

New studies find carcinogens in vg and pg at high temps, even in tootle puffers

How true.

 

[Eskie]

I had trouble copying and pasting from the link below. It may be that the coil turns the liquid into vapor by boiling the water content. The boiling points of pg and vg may be irrelevent. may be adding a bit of water to aid the boiling is good for safety? Does the water in eliquid help prevent over heating when firing? Do we understand how e liquid is turned into vapor. Do those rocket scientists in Cali know?

"The heat evaporates the water first which steam atomizes the glycerol or propylene glycol (mpg) molecules. The vapour temperature will not be far above water boiling point, otherwise it would burn the user's tongue. ">2 mL2 mL e-liquid is incomparably less than formaldehyde consumed from fish..."
How does propylene glycol/glycerin form formaldehyde/acetaldehyde when vaporized with a vaporizer?

That link leads to the opinion of some random guy with no offered credentials giving an internet answer to an internet question. That is not peer reviewed published data. And yes, that does matter, otherwise all we're doing is cherry picking snippets of statements made by folks of unknown qualification and holding them out as proven science.

Bashing the "rocket scientists" and "so called scientists" of CA and their funding from the State of California will not change the fact that within the limitations of the test method as set out, they got higher amounts of aldehyde production with higher temperatures. And if you somehow believe that because CA collects taxes on tobacco they would go bankrupt if everyone stopped smoking (they wouldn't) and monies from government, BT, and BP all fatally taint any research performed, just who do you expect will pay for it? Evolv, the makers of TC boards who implied that made them safer with no experimental evidence to support it? If no one can be trusted, where will that leave anything?

That's really interesting. Unfortunately there's a PayWall on the paper. I'm going to see if I can get it via the University network...

If you're talking about that link to the 2014 study regarding aldehyde production from e-cigs with increasing voltage, don't knock yourself out. That's been batted around already and not applicable to either the model tested here, or to contemporary vape gear.

 

[zoiDman]

I think my brain is boiled at this point.

You need a TC Brain upgrade.

Check Out the Avatar to the Left of this Post for any Example of one.

LOL

 

[Katya]

I'm beginning to understand now........that I don't know jack snark about physics.

I think my brain is boiled at this point.

Ditto.

Carry on, my friends.

 

[Domejunky]

That link leads to the opinion of some random guy with no offered credentials giving an internet answer to an internet question. That is not peer reviewed published data. And yes, that does matter, otherwise all we're doing is cherry picking snippets of statements made by folks of unknown qualification and holding them out as proven science.

Bashing the "rocket scientists" and "so called scientists" of CA and their funding from the State of California will not change the fact that within the limitations of the test method as set out, they got higher amounts of aldehyde production with higher temperatures. And if you somehow believe that because CA collects taxes on tobacco they would go bankrupt if everyone stopped smoking (they wouldn't) and monies from government, BT, and BP all fatally taint any research performed, just who do you expect will pay for it? Evolv, the makers of TC boards who implied that made them safer with no experimental evidence to support it? If no one can be trusted, where will that leave anything?



If you're talking about that link to the 2014 study regarding aldehyde production from e-cigs with increasing voltage, don't knock yourself out. That's been batted around already and not applicable to either the model tested here, or to contemporary vape gear.

This one?

An investigation of the degradation of aqueous ethylene glycol and propylene glycol solutions using ion chromatography - ScienceDirect

 

[sofarsogood]

That link leads to the opinion of some random guy with no offered credentials giving an internet answer to an internet question. That is not peer reviewed published data. And yes, that does matter, otherwise all we're doing is cherry picking snippets of statements made by folks of unknown qualification and holding them out as proven science.

Bashing the "rocket scientists" and "so called scientists" of CA and their funding from the State of California will not change the fact that within the limitations of the test method as set out, they got higher amounts of aldehyde production with higher temperatures. And if you somehow believe that because CA collects taxes on tobacco they would go bankrupt if everyone stopped smoking (they wouldn't) and monies from government, BT, and BP all fatally taint any research performed, just who do you expect will pay for it? Evolv, the makers of TC boards who implied that made them safer with no experimental evidence to support it? If no one can be trusted, where will that leave anything?



If you're talking about that link to the 2014 study regarding aldehyde production from e-cigs with increasing voltage, don't knock yourself out. That's been batted around already and not applicable to either the model tested here, or to contemporary vape gear.

What I drew from the comments is a likely answer to the question i was googling which happened to be "how does vegitable glycerin get vaporized' or words to that effect. I suspect boiling of the water content is the answer. It sort of makes sense.

 

[Eskie]

This one?

An investigation of the degradation of aqueous ethylene glycol and propylene glycol solutions using ion chromatography - ScienceDirect

No, it was the first one, Carbonyl Compounds in Electronic Cigarette Vapors: Effects of Nicotine Solvent and Battery Output Voltage | Nicotine & Tobacco Research | Oxford Academic

that dealt with aldehyde production in e cigs. The Rossiter article you link to is a theoretical study of glycerol breakdown products in different settings (non-vape related) and in the presence of different metals (in particular, Copper). I don't know enough (well, just about anything) about solar panel construction to understand the relevance of glycerol oxidation and solar panels.

 

[Domejunky]

No, it was the first one, Carbonyl Compounds in Electronic Cigarette Vapors: Effects of Nicotine Solvent and Battery Output Voltage | Nicotine & Tobacco Research | Oxford Academic

that dealt with aldehyde production in e cigs. The Rossiter article you link to is a theoretical study of glycerol breakdown products in different settings (non-vape related) and in the presence of different metals (in particular, Copper). I don't know enough (well, just about anything) about solar panel construction to understand the relevance of glycerol oxidation and solar panels.

I read the first one. It cited, but didn't mention, the water vapour mechanism...

 

[Eskie]

What I drew from the comments is a likely answer to the question i was googling which happened to be "how does vegitable glycerin get vaporized' or words to the effect. I suspect boiling of the water content is the answer.

But there was no water in the liquids tested. It was just VG, PG, a 50/50 PG/VG, and some e-liquids they picked up at the local 7 11.

 

[sofarsogood]

But there was no water in the liquids tested. It was just VG, PG, a 50/50 PG/VG, and some e-liquids they picked up at the local 7 11.

I find this, "vegetable glycerin is 99.7% pure, with the remaining 0.3% being water." Not a lot of water. I looked for evidence about consituents of PG, nothing about water although both attract water. Water is often added to e liquid but i don't do that but may be I'll try some.

It appears the boiling point of PG is 370 F and for VG 554 F and yet I'm sitting here vaping and the AF firmware reports that my last puff (1.2 seconds) was 235 F max temp (firing at 30 max watts) and vapor production was right where i like it with a saturated coil, nice texture and warm (and not a hint of formaldehyde). If the boiling points are so far above my coil temperature, which is hot enough to boil water, what's producing all the nice vapor I'm getting? And I just reduced max temp to 210 F and the fiirmware reports it used 10 watts to hit that temperature and vapor production was not so bad but may be a bit cooler than my preference.
The coil I'm using at the moment is 10 wraps of 28 guage stainless at 3mm, resistance is locked at 1.38 ohm.

 

[cigatron]

Well, that didn't take long. I learned a little more about Leidenfrost effect but as it relates to real world vaping I can't tell. In in order to grasp it entirely one would have to be formally schooled in physics. I don't have those skeeals, so I'm out.

 

[GeorgeS]

The boiling point of Glycerol (VG) is 290 °C (554 °F; 563 K)
The boiling point of Propylene glycol is 188.2 °C (370.8 °F; 461.3 K)

So how can we say a high VG mix cant get to 470°F ?

What am I missing here? The report mentioned nasty stuff being generated off of 100% VG at as little at 210C. I'm not sure where your getting the "470F" from. Both are way below the boiling point of VG as well.

I usually vape nearly 100% VG and get plenty of vapor at 380F. Add as much as 33-66% H2O and that temperature lowers to closer to 300F.

 

[DPLongo22]

 

[Katdarling]

 

[zoiDman]

 

[DaveP]

single or dual coil? It's been said here ss316l can be finicky in single coil (I wouldn't know only dc here) ss430 has been recommended which I want to try but haven't found trustworthy source for 26 awg

Single, 3mm, 28ga.

 

[DaveP]

Once again, dry type hits don't seem to be necessary for higher temperatures and higher aldehyde production. It's only a "seem" but erring on the side of safety is never a bad thing, IMHO, and "higher" may be very relative. Relying on taste, alone, may not be the best indicator.

I think we do need more technical information. Is a TC mod reading resistance, reactance, or impedance? I've heard it explained as resistance change in the wire as the temp changes. How do various wires relate to the algorithm in the firmware? And most of all how accurate are the readings? How can we sense the danger point on a non-TC vape? Does it burn our tongue? Do we just sense something more than warmth? Can we even tell when bad chemicals are in the vape?

 

[DaveP]

Ok I'm not even close to finishing this thread but I'm giving up on it. You TC fanboys are worse than what some here claimed provape fans are.

There's one simple fact about kanthal all of you are missing. The fact that it has a stable resistance and heat flux means the temp is a direct function of power applied. So this myth that you can't dial in a coil temp with kanthal needs to stop. It's done EVERY day in many appliances from toasters to vape mods.

You can dial in a coil temp with Kanthal, but how do you detect 200F +/-? All the temp documents say that Kanthal doesn't produce a linear response in temp or resistance with a linear voltage change. On a toaster you just dial up the voltage to the number that's always worked for your favorite shade of burnt bread. If it's electronically controlled, that's commonly achieved using a thermistor feeding a voltage controller for feedback.

OTOH, I agree that once you learn to sense the danger point in a vape you can control Kanthal by your own sense of what's safe. For me, it's anything more than a very slight warmth at the drip tip.