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

[mikepetro]

Wow. Awesome info you've gathered and shared.

What did you mean by this, besides the obvious:

The coil temp is being controlled and the wick is being heated by the coil and has no way to exceed the coil temp, so indirectly, the wick is temp controlled, no?

You're right, wick temp is controlled indirectly. I guess what I meant is that wick temp is not repeatable. While it doesnt exceed coil temp, it can be high or low depending on whether you are chain vaping or not etc.

Honestly, I dont know that wick temp makes any difference to us. It was just one of the question that came up in this thread and since I could measure it, I did.

 

[mikepetro]

So a 400-450F range should be within a "window of safety" based on the data presented with the above reactor temperature study. Now to see if the reactor and a modern generation tank behave the same.

Mike, you've gone above and beyond with this. And no, I'm not suggesting you do the chemical analysis too, unless you have access for that testing as well. And if you do, I'd love to know where you work because it sounds like someplace I'd love to submit my resume.

First, no, I cant do the chemical analysis, my job isnt quite that cool.

Actually the temp controller you see is one I built to do stuff around the house like Sous-Vide cooking, BBQ smoking, coffee roasting, etc. For example, plug a crockpot into the front receptacle, and a temp probe in the pot, and it will control it very precisely. Plug in a draft fan, stick the probe in the smoke chamber, and it will maintain a precise temp in a smoker. I used it for testing nic degradation due to heat in the pic below.

Anyway:
To me it all comes down to heat. What the reactor showed us is simply what heat does to vg/pg. At X temp you get Y nasties. That was the thing that lit the light bulb in my head, it was device independent. Heat VG up to 410 and you get nasties. Heat is heat is heat. I dont think it matters whether that heat is coming from a reactor or an atty coil.

I think the real question is what temp your device is heating the juice to. If you have a TC device then you have a pretty good idea. If you dont, then it would take testing akin to what I have done here to really know.

 

[Eskie]

First, no, I cant do the chemical analysis, my job isnt quite that cool.

Actually the temp controller you see is one I built to do stuff around the house like Sous-Vide cooking, BBQ smoking, coffee roasting, etc. For example, plug a crockpot into the front receptacle, and a temp probe in the pot, and it will control it very precisely. Plug in a draft fan, stick the probe in the smoke chamber, and it will maintain a precise temp in a smoker. I used it for testing nic degradation due to heat in the pic below.

Anyway:
To me it all comes down to heat. What the reactor showed us is simply what heat does to vg/pg. At X temp you get Y nasties. That was the thing that lit the light bulb in my head, it was device independent. Heat VG up to 410 and you get nasties. Heat is heat is heat. I dont think it matters whether that heat is coming from a reactor or an atty coil.

I think the real question is what temp your device is heating the juice to. If you have a TC device then you have a pretty good idea. If you dont, then it would take testing akin to what I have done here to really know.

A very handy thing to have around the kitchen. Next time I'm in Bed, Bath, and Beyond I'll look for it in the small appliances section.

I agree heat is heat. Your thermocouple independently established that TC as we know it is fairly accurate in direct coil monitoring. As you also noted, temps are different in the wick, although obviously not exceeding the maximum temperature of the coil. In the reactor testing, they did report the vapor produced and captured was never more than ~120F (? so as not to have a negative effect on the chemical capture pods things they used). Which sounds very much like what we as vapers experience, we don't suck 400F vapor into our lungs or we'd all be in an ICU with respiratory burns. The next hopefully step of reproducing in an atty and measuring the produced products as was done with the reactor might show even lower thermal organic breakdown products or the same. Which is still valuable information as the safety factor might be a bit better "padded" than the reactor numbers alone.

Either way, it does show TC as useful not only in the type of vape we get, but perhaps/hopefully protection from breakdown crud. It also seems from your observations of vaping on it at the time of being able to sense the flavor getting a bit funky above 500F, which may be helpful to power/wattage users. But it does look like a tight, low airflow mtl setup can lead to higher than expected temperatures (at least by me) without "pushing" really high power settings.

 

[mikepetro]

In the reactor testing, they did report the vapor produced and captured was never more than ~120F (? so as not to have a negative effect on the chemical capture pods things they used). Which sounds very much like what we as vapers experience, we don't suck 400F vapor into our lungs or we'd all be in an ICU with respiratory burns.

Well, for what its worth, the sensor placed in the airflow of the driptip measured 107-112 degrees at the same 400 degree TC setting. Curiously, tight or loose airflow settings made little difference.

 

[Eskie]

Well, for what its worth, the sensor placed in the airflow of the driptip measured 107-112 degrees at the same 400 degree TC setting. Curiously, tight or loose airflow settings made little difference.

Huh. Airflow didn't change the temp at the drip tip. I would have expected the opposite with changing the airflow.

 

[mikepetro]

Huh. Airflow didn't change the temp at the drip tip. I would have expected the opposite with changing the airflow.

Yep, surprised me too. Repeated the experiment several times to be sure.

 

[Eskie]

Yep, surprised me too. Repeated the experiment several times to be sure.

And this is why science works. Data is good, assumptions less so.

 

[zoiDman]

Well, for what its worth, the sensor placed in the airflow of the driptip measured 107-112 degrees at the same 400 degree TC setting. Curiously, tight or loose airflow settings made little difference.

How sensitive do you think the Sensor is to Convection vs. Conduction?

 

[mikepetro]

How sensitive do you think the Sensor is to Convection vs. Conduction?

More accurate with conduction IMHO.

A good read on the topic:
https://ams.confex.com/ams/pdfpapers/67056.pdf

 

[mikepetro]

Wasn't questioning your mixing skills, was going to suggest trying different pg/vg ratios to see if it has an effect on that temp leveling that you saw. Higher pg might bring the temp down from 400, higher vg might raise it.

Mixed some vg with 10% distilled water to more closely match the viscosity of pg. Ran both mixtures through several times. I did not see any repeatable differences in the temperature of the wick or coil that I could attribute to either juice.

 

[zoiDman]

More accurate with conduction IMHO.

A good read on the topic:
https://ams.confex.com/ams/pdfpapers/67056.pdf

Yeah... That is what I Suspected.

Not say'n that the Temperature Range you saw is Unreasonable. Because if you get Much "Hotter" at the Relative Humidity of a Hit, it is going to start to feel Uncomfortable.

And there just Isn't a lot of Thermal Density at the Coil as compared to the Amount of Ambient Temperature Air that enters an Atomizer.

Anyway. Great Job on what you are Doing. And like I said earlier, Real World Data is Very Interesting to see with all of this.

 

[SK1LL]

I dug out my deringer thingy and have been fighting with my titanium after delving into one of the other threads. I've since been bundling up and throwing out ....feeeeeet of wire
So I decided to try twisting, why note waste more right? ended up with this..
View attachment 651101
Since I didn't wanna snip it, I just tucked it in and called it a sleeper build
View attachment 651097
good thing titanium is resilient. That's 26g
View attachment 651099 this means I'm not doing mtl anymoreat least I've got a good stock of juice left

Still searching for an answer to my temperature problem.
Were the VTC minis inaccurate?
I've shelved my mech mods after reading here but..
Is this the wrong thread for me?
Should I even be worried about this?

 

[Ryedan]

Thermocouple Elements, Fine Gage, Usheathed Thermocouple, Bare Thermocouple

Edit: Above link is for uninsulated, this is what I used
Insulated Thermocouples

Thank you

 

[David Wolf]

More accurate with conduction IMHO.

A good read on the topic:
https://ams.confex.com/ams/pdfpapers/67056.pdf

Excellent testing Mike, pretty much confirms testing I've seen on YouTube that DNA boards and some other mods do are pretty accurate at temp control (though others do not). Now what I would like to see is testing for aldehydes off a setup like yours, since you can't conclude the juice is really getting to the same temp as the coil because it vaporizes at a lower temperature. Coil temperature does not necessarily equal juice temperature. I suspect juice in direct contact under the coil approaches coil temperature while most of the juice vaporizing does not and that aldehyde formation isn't anywhere near as high as in the OP "tube test". Only testing of atomizers for aldehydes off of a real world setup like yours will provide anything conclusive in that regard, and the one realistic test I read didn't produce anything near the levels of aldehydes as in the OP, however it didn't measure coil temperature. Without conclusive realistic testing temperature control is a conservative measure that makes sense, but I'm not going to get all worked up over the OP, though that test is excellent regarding the effects of temperature of PG and VG (but not atomizer coil temperature effects on PG and VG).

 

[Eskie]

Excellent testing Mike, pretty much confirms testing I've seen on YouTube that DNA boards and some other mods do are pretty accurate at temp control (though others do not). Now what I would like to see is testing for aldehydes off a setup like yours, since you can't conclude the juice is really getting to the same temp as the coil because it vaporizes at a lower temperature. Coil temperature does not necessarily equal juice temperature. I suspect juice in direct contact under the coil approaches coil temperature while most of the juice vaporizing does not and that aldehyde formation isn't anywhere near as high as in the OP "tube test". Only testing of atomizers for aldehydes off of a real world setup like yours will provide anything conclusive in that regard, and the one realistic test I read didn't produce anything near the levels of aldehydes as in the OP, however it didn't measure coil temperature. Without conclusive realistic testing temperature control is a conservative measure that makes sense, but I'm not going to get all worked up over the OP, though that test is excellent regarding the effects of temperature of PG and VG (but not atomizer coil temperature effects on PG and VG).

This is speculation that requires testing as you point out, but I would look at the results from the reactor testing as the upper limit on temperature and breakdown products as it does not totally recreate the conditions of a typical tank, coil, and wick setup. It is quite possible that with "real world" tanks, the aldehyde levels will be lower at a given temperature compared to the reactor model. But like anything, assumptions are one thing, data far better. It is the natural next step, and given how far it's already been taken, it's tough to imagine a study like that will not be sponsored and conducted in the near future, if not already going on.

 

[mikepetro]

Still searching for an answer to my temperature problem.
Were the VTC minis inaccurate?
I've shelved my mech mods after reading here but..
Is this the wrong thread for me?
Should I even be worried about this?

Worried, IMHO, No....

Vaping is inherently safer than smoking, PERIOD.

This is a safety nuance like adding airbags in addition to safety belts. I am pulling numbers out of my azz here for example sake, but lets lets say vaping has 95% less nasties than smoking, then avoiding high temp vaping bumps it up to 97% less nasties.

As for the VTC minis, I dont have one, so I didnt test it.

 

[GeorgeS]

Still searching for an answer to my temperature problem.
Were the VTC minis inaccurate?
I've shelved my mech mods after reading here but..
Is this the wrong thread for me?
Should I even be worried about this?

The VTC mini's (I own two) are accurate enough in TC. However not all atomizers are good choices for use in TC.

• good mechanical screw termination is preferred over simple physical contact termination
• some atomizers have to high or unstable parasitic resistance

then again, issues with TC in general it makes more sense to start a dedicated thread in the TC subforum looking for help rather than steer this thread off topic.

On topic: I can see how the difference in temperature between the middle of the coil and the ends can help validate why many of us can get a decent vape at XXF and even more vapor production at XXF+20F.

My theory is that the higher temperature setting allows more of the coil to reach vapor temperature hence the higher vapor output.

 

[Eskie]

Worried, IMHO, No....

Vaping is inherently safer than smoking, PERIOD.

This is a safety nuance like adding airbags in addition to safety belts. I am pulling numbers out of my azz here for example sake, but lets lets say vaping has 95% less nasties than smoking, then avoiding high temp vaping bumps it up to 97% less nasties.

As for the VTC minis, I dont have one, so I didnt test it.

I'd even put it as side air bags in addition to front air bags. Current setups do appear to be way safer than the older clearos, especially when taking into account those early studies were basically burning the crap out of those things. As I've posted before, as nice as all this info is, it hasn't changed my vaping pattern which whether with TC or even wattage, I always go for only a warmish vape.

 

[mikepetro]

since you can't conclude the juice is really getting to the same temp as the coil because it vaporizes at a lower temperature.

That depends on the temp you are running at and the boiling point of your juice.

Coil temperature does not necessarily equal juice temperature. I suspect juice in direct contact under the coil approaches coil temperature while most of the juice vaporizing does not

I measured the temp underneath the coil. We can clearly hit the temperatures our TC mods are telling us, and temps that the reactor was sampling at. In wattage mode I measured temps hotter than one would assume, and easily past the nastie points quoted by the study.

Juice reaches a "boiling point" and then vaporizes. You can indeed heat the juice beyond that boiling point, where the juice on the surface of the coil is boiling, but the juice trapped in the wick UNDER the coil gets heating beyond boiling until it reaches the surface, if the coil is hot enough.

I "tasted" something bad starting at around 500 degrees, and it wasnt a dry hit. I made sure it wasnt a dry hit by taking a visibly saturated wick and throwing 540 degrees at it, the wick was saturated but it tasted bad. This was unflavored juice, so it had to be pg/vg itself that tasted different. If it all flashed off at the boiling point then why would it taste any different?

Its all about the boiling point! Until the liquid is boiling, no vapor is coming off!
I have read tons of research on this, until the liquid is boiling, no vapor is coming off. When I talk with ecig engineers, they all talk about bringing juice to boiling point in order to create vapor. I proved that to myself, I lowered the coil temp down to 330 degrees, and I got nothing! Now, the pg/vg ratio of your juice has a lot to do with what that boiling point is. The more VG in your juice, the higher the boiling point.

• Boiling point of PG 370.8 °F
• PG starts giving off nasties at ~480 °F
  
• Boiling point of VG 554 °F
• VG starts giving off nasties at ~420 °F

So in order to get vapor you need to reach the boiling point. Pure VG is already giving off nasties when it hits its boiling point.

In reality, we all dilute our VG which lowers its boiling point. Nic itself, flavors, PG, water, alcohol, etc all lower the boiling point. The boiling point (vapor point) of your specific juice will be entirely dependent on the recipe.

The fly in the ointment is that the temperature range between boiling(vapor) and nasties is fairly narrow. Getting an ejuice with a boiling point below 420 is a good start, then ensuring your mod doesnt exceed 420 is a good next step.

We all essentially design our own vape. We choose what atty/coil/mod/setting/juice etc to use. The OP study put it well:

prevention of high temperature and overheating during vaping to minimize the formation of toxic chemicals is a design feature that must be considered

In other words "Temperature Matters"!

 

[kross8]

thanks Mike for all of your tests and work on the subject........lurking often.