Outpourings of Hot Air

I’m pretty sure we’ve been down this road before. The whole formaldehyde scare – leading to the “10 times more cancer causing chemicals” headlines. That particular study (which started life in the NEJM as a letter to the editor) has been roundly debunked – not least of which because to inhale burning e-liquid, is frankly a rather dumb idea. Any researcher that believes us vapers do that on a regular basis, most definitely need to get out more.

But it seems that these budding researchers have nothing better to do than to come up with new ways to thoroughly burn e-liquid so they can tell the media that “e-cigs are bad mmmkaay?”. In this case, more research (funded by the University of California Tobacco Related Disease Research Program) at Lawrence Berkeley National Laboratory have added more wibble.

From the abstract:

Yes, by burning the liquid. Don’t these folk get it? Well, no of course they don’t. They are just looking for any outlandish excuse to bolster their ever weakening defense against what is proving to be, a safer alternative to smoking – they can’t have that now, otherwise all their funding goes away!

Let’s skip over the usual introductory stuff – the whole “vaping has grown exponentially in the United States” thing, that’s typical soundbite stuff that those in ‘public health’ like to use when informing coercing legislators. So we’ll skip straight to the heart of the matter.

Oh wait, that’s still part of the “introduction” – nice to see these researchers are well versed in how to phrase things for policy makers to go “well this study says this, so let’s ban it”. The rest of the introduction doesn’t get better either. Although I did enjoy this snippet:

General question to my readers – in your device (whatever that is right now) could you approximate how many “puffs” you get from a fully charged cell? I’m genuinely curious!

Erm, what? Geometry? Unless they are specifically talking about how the air-flow is directed over and around the coil, I can’t see geometry having much of an actual effect on the temperature at which liquid is vapourised.

Unlike previous “studies” into burning e-liquid, these researchers splashed out a bit and got themselves a CE4 and an Aerotank, they also made their own “vaping machine” instead of using the more traditional smoking machines. You know, just to be..er.. different.

I’d be willing to bet you can guess which flavours they chose right?

Yep, bubblicious – or more to the point, bubblegum. Seriously, what is it with these researchers and their fascination with bubblegum? Oh, it’s also worth pointing out that they didn’t know the PG/VG ratio from the other flavours. Bubblicious is available in two ratios – a “drip” variety 30/70 (PG/VG) and a “standard” variety 60/40 (PG/VG). Also, the Mojito Mix is from the same maker, but for some reason, that and the Apollo e-liquid were at 18mg/ml of nicotine, while Bubblicious was at 24. Nothing at all like consistency there.

Oh my. Enter stage left, flaw number one. While there are still plenty of Vision Spinner mods out there with the variable voltage (I had one just under two years ago) it is not the most common on the market right now. In fact, I’m relatively sure that the Vision Spinner II isn’t as widespread as it once was.

Enter stage right, flaw number two. This one is by far the biggest flaw out of the whole study (and that’s saying something). For instance, on my Mini VTC with a Nautilus X at 15W, my average “puff” is around 2.5-3.4 seconds in length. Just for kicks, I’ve just taken a 5 second long puff. Never again. On a tank that is designed for mouth to lung (to mimic the act of smoking), it is actually rather painful (for me at least) to draw for five seconds. To then repeat that every 25 seconds is as far from real world as you can get.

Just for my own curiosity, I asked my followers on Twitter what the average (MTL) puff was, the majority of those that responded were like me – between 2 to 4 seconds. Had the occasional outlier with a 4-5 second puff. I guess the follow-up question to that would be – how often they puffed?

Of course, the researchers needed to know what was in the liquid they were testing – you know, for baseline readings and so forth. So they decided to “incubate” the liquids at different temperatures between 80 and 280 degrees centigrade. This is what they found from the 200 degree incubation:

From the liquid incubation, the researchers deduced that because the flavouring compounds were present in the liquid, and because at 200 degrees the incubation temperature were comparable to those reported near the heated coil (but not the coil itself), the compounds were likely to be in the generated aerosol, and in greater quantities. Let’s not forget that the CT liquid is a standard tobacco flavour.

Unless I’m completely useless, if you take 10ml of liquid and vapourise it, the component parts of that liquid (if it ever returns to liquid form) will remain in the same quantity or less. So with that in mind, how can a portion of the liquid actually create more of itself in aerosol?

This is where it gets interesting. Not only did the researchers incubate the liquid at 200 degrees (apparently close to the temperature measured somewhere near the coil), they also measured the temperature of the vapour itself.

Notice anything “unusual” here? The vapour generated from the CE4 was warmer than that from the AeroTank Mini. Well go figure Einstein. The AeroTank was so named because of the airflow. More air flowing over a coil at a set level (and we’re talking early hardware here) will result in a cooler vape. Less airflow means the vapour is warmer. That’s not exactly rocket science now is it?

Well, there’s a no shit sherlock moment. But are you ready for a facepalm moment?

Unlike in their simulation, vapers don’t inhale all the vapour. Some of it actually escapes, especially in mouth to lung when some is expelled (at least in my case) prior to the actual inhalation. So to say that the nanograms emitted per millilitre of e-liquid consumed is being inhaled, as is being implied here, is ridiculous. It is of course completely different for those that like a direct to lung hit, but even then a lot of the vapour still escapes – usually through the airflow.

But it gets better.

Now this reminds of another piece of research by, none other than Dr Konstantinos Farsalinos. Dr Farsalinos also presented at the Global Forum on Nicotine and referred to this exact issue. Amazingly, the researchers of this study did cite Dr Farsalinos’ work, but only in relation to the puff cycle and not to the simple fact that if you burn e-liquid you will get aldehydes. Not to mention that in those circumstances, actually inhaling the vapour is incredibly disgusting and painful.

Remember that CT liquid being a standard tobacco flavour? Well, even though there weren’t any additional flavourings, it still produced some nasties at 3.8V and above:

But here’s the thing, the data displayed in Figure 2 (above) is presented as a result of mass of compound emitted per unit mass of e-liquid and not as a mass of compound per puff. Completely different scaling. As we know the AeroTank was a “better” tank than the CE4, not least of which due to the coil design – bottom feed rather than top-feed on the CE4, but the results shown in the study don’t reflect that. It is only reflected in the supplementary information:

A rather significant difference. (h/t Shawn Avery at Daily Drip for highlighting that)

That’s exactly what happens when you get a dry puff – which we already knew. But according to the researchers own words, they had more accurate results at 3.8V. In other words, readings generated from use at 3.3V were ND – not detectable, or not detectable at any significant quantity:

This demonstrates the “detected levels” at the steady state (temperature wise) of a CE4 using the tobacco flavour. Steady state refers to the higher temperature levels (shown in Figure 1 above).

Well there’s another no shit sherlock moment. The more energy applied, the greater the vapour generation. It’s not as if we didn’t already know that. But there’s more.

Well of course your going to find more acrolein at higher voltages than at lower ones – it’s known as the dry puff, you should know you referenced Dr Farsalinos’ work!

So use a CE4 for 5 seconds at a time, every 25 seconds for 25 minutes, then repeat that nine times and not clean the coil to mimic “conditions that may be commonly used by many vapers”. No. Never in a gazillion fucking years would I, or any other vaper do that. To properly research a subject you must have a basic understanding of the subject matter – in this case, us. Something that is quite clearly lacking here.

In case you didn’t know, these researchers have no idea that the industry and technology involved with vapour products has already evolved to that point. But it gets even more interesting.

So after seriously abusing a single coil with 5 second puffs at 25 second intervals for 25 minutes nine times the researchers then decided to “vape” pure PG and pure VG – at 3.8V – where they’ve been “finding” the most nasties and this is what they found:

Remember, thats nanograms per milligram. Toxicology 101 folks, the dose does not equal poison.

But why worry about understanding the subject matter at hand, after all it’s not as though this particular research hasn’t been done before is it?

(Image credit Diego Cervo/Shutterstock.com)