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Fully expect to be downvoted for this - but I found this study on synthetic cooling agents in e-cigarettes, and wanted to share..
submitted almost 4 years ago by noidontwantto

The general sentiment in other subreddits about vaping when encountering studies that shine an unfavorable light on it seems to be to castigate the study and person, but this is a relatively new study, and I thought it was worth sharing.

https://www.biorxiv.org/content/10.1101/2021.06.09.446946v1.full.pdf

> This work was supported by the National Institute on Drug Abuse (NIDA) of the National Institutes of Health (NIH) and the Center for Tobacco Products of the US Food and Drug Administration (FDA) (P50DA036151 and U54DA036151; Yale Tobacco Center of Regulatory Science, TCORS); and National Institute of Environmental Health Sciences (NIEHS)

I'm not going to opine in this post about the study, other than it's well written.

Interested to hear the community's thoughts.

Comments
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33 points
 
by WyomingCountryBoyalmost 4 years ago

I am not trusting a damn thing coming from US studies considering they are almost all funded by big tobacco and anti groups. I prefer NHS out of England who isn't funded by them.

7 points
 
by travioso304almost 4 years ago

Same. They've got the war on vapes (big tobacco) and the war on kratom (big pharma). they (the US) are even trying to drag WHO into the kratom bit.. FDA got so shitty with kratom they are using phrases like associated with kratom for death counts. Meaning someone could be struck by lightning and if they had kratom in their system that's a death in their book.

Edit: Nothing to do with this study.. Just in general..

3 points
 
by Sally-Seashellsalmost 4 years ago

Same shit different day with this across the board. Kratom will get approval when some pharma company can make money from it, like marijuana and psilocybin but while it cuts into opiate sales it's dangerous.

21 points
 
by katzeye007almost 4 years ago

They claim menthol or ice is potentially clastiogenic (sp) / cancerous yet it's not listed anywhere as a know carcinogen

11 points
 
by 25c-nbalmost 4 years ago

To be listed as a known carcinogen, they would have to prove it is with studies. To do that, they need studies like this which highlight potential candidates, bringing the attention of other researchers who can perform further research.

1 points
 
by noidontwanttoalmost 4 years ago

I think the big thing to me was the bits about liver lesions

17 points
 
by iowajoshalmost 4 years ago

>Orally dosed in rats.

2 points
 
by Segontia18almost 4 years ago

Exactly. There's a huge difference between inhalation and administering a substance orally. Not even mentioning the fact that normally, researchers over-dose the substance they want to study in order to provoke a reaction (on average, vapers use 0.5%; 1% is acceptable, but 3% is "un-vape-able" for most vapers) and humans are not rats, breeded to develop diseases.

As far as I know, inhalation is not connected to liver damage. Smoking can cause kidney cancer, because smokers swallow some of the toxins in smoke, but I've never heard of (menthol) smokers developing diseases connected to the liver.

However, I'm not a scientist And until we know more about this a little caution won't hurt!

4 points
 
by katzeye007almost 4 years ago

I didn't read the whole thing, how did they control for that? What was the sample population?

-1 points
 
by noidontwanttoalmost 4 years ago

> JECFA established a No-Observed-Adverse-EffectLevel (NOAEL) of 8 mg/kg-bw for WS-3 (21,22). For WS-23, a NOAEL of 5 mg/kg-bw was determined for oral administration, with higher doses causing kidney and liver lesions (21,23)

And just a bit further down.. > A WS-23 inhalation exposure study by an E-liquid manufacturer determined a NOAEL of 29 mg/kg-bw (342 mg/m3) (24)

13 points
 
by TheSuperSkrullalmost 4 years ago

This was a very thorough paper but the thing that really struck me was that they used 60kg as assumed body weight for their MOE calculations. The scientific convention almost everywhere (including the CDC and ATSDR) is to use 70kg as assumed body weight. They give no explanation as to why they have gone against scientific convention and chosen 60kg. Body weight is the key denominator when calculating estimated exposure dose and given how many fields in table 3 are close to <100 MOE I would expect that they would be over 100 had they used 70kg as the assumed weight.

The other thing is that when testing the flavour concentrate they diluted it down to 1-3%. A good proportion of DIY'ers won't be able to tolerate Ws-23 at those % (although a not insignificant proportion probably can).

I read a lot of scientific papers as part of my work and unless a paper has an incredibly robust level of evidence; conclusions are often stated in the most conservative manner, with many balanced calls to study limitations and avenues of further research. This paper does feel a bit unusual in how it read with regards to that (but that could just be reader centred bias, perhaps)

Safety data for the vast majority of flavourings we use are almost always based on oral intake, Ws-3 and WS-23 seem no different it seems, we just don't know how it translates to inhaled intake. The interest in coolants specifically, I take it is down to increased use in juices following various regulations and laws in the USA?

Bottom line, most people get into vaping due to wanting to minimise harm from smoking, and if you would rather be cautious and limit your coolant use until further research comes out, there is absolutely nothing wrong with that; you should enjoy your vape and not have feelings of guilt attached to that. If more confirmatory research does come out, much like DAAP, you can make a personal choice around the risks when the picture becomes clearer and that is okay as well. If you prefer to continue to vape WS-23 until hell freezes over, that is cool too!

7 points
 
by WyomingCountryBoyalmost 4 years ago

The average male over 20 in the US weighs 89kg, in Europe 70kg. That, and as you said, the percentage. I mean we have already caught them out literally burning the coils to produce vapor no vape user would even be able to handle and here using unrealistic body weights and concentrations. They also do not even bother to compare it to what is in cigarette smoke.

5 points
 
by August2_8x2almost 4 years ago

I diy and i prefer a chilly vape, but 0.5% in a mix is almost painful. Normally im somewhere between 0.2 amd 0.3% depending on sensation thatll go best with the flavor profile and the season. If its winter, im not after super cold lol.

I cant even imagine trying 3% let alone 1%. Wtf were they tryin to test, what sucking Frosty's dick is like?

2 points
 
by KingAthelasalmost 4 years ago

It's so weird how different we all can be. Unless I'm using mints with coolants added already, I regularly use WS-23 at 2.5-5%. Even went up to 6 with one mix but it was almost too much for me lol. Still vaped all 30 ml though eventually.

Edit: to clarify, I only use WS-23 every 4-5 mixes nowadays.

1 points
 
by Diggerinthedarkalmost 4 years agoWTF is a "Terpene?"

Hi, it seems like you know what you're talking about here so I'll ask you, what are regular menthol crystals like in relation to these synthetic ws ones? Are they even similar? I only use traditional menthol crystals, the kind that you would put in hot water to inhale and reduce congestion. Hope you have a great day.

3 points
 
by TheSuperSkrullalmost 4 years ago

Wow, you use pure menthol crystals? That is hardcore DIY! Menthol crystal inhalation has been around for many years before vaping so I am guessing there has been many studies on it, but surprisingly I couldn't find much data on human safety studies. Menthol on its own is regarded as "safe" by the FDA and FEMA and the recent ban on menthol in cigarettes is solely based on the evidence that mentholated cigarettes make it easier to take up and stick to smoking tobacco, and even more so in community groups that are already disadvantaged in their health economy.

Menthol crystals in themselves can cause contact dermatitis and I found a few case reports of serious adverse effects, one for a guy in Cleveland who had eaten 2 bags of cough drops every day for 20 years presented with severe neurological and gut symptoms that got better with abstinence, and another case report of a guy in India who was cleaning out a vat in a peppermint candy factory without PPE and went into a coma and died from the menthol exposure.

I think the biggest caution with using your own raw menthol crystals for DIY is making sure you are accurate in measuring, I can't honestly give any recommendations as I wouldn't know where to start with that! I have used menthol crystals in my own home made muscle rub and I had to prepare that outside with gloves, mask and goggles and I still felt dizzy from the vapours!

12 points
 
by SolarAUalmost 4 years ago

Damn I'm a heavy coolant user so this is a bit concerning to me. If the figures are right my use of WS-23 at 2% in ~8mL eLiquid per day exceeds the safe margin of exposure. Might have to rethink things

17 points
 
by and_dont_blinkalmost 4 years ago

I'd keep an eye on it, and less flavorings is always good, but also wait for this to get replicated and really reviewed. There are a whole bunch of studies like this churned out in the sciences that end up being heavily flawed. For example, the one that came out saying rats fed genetically modified corn developed tumors complete with press releases and images: https://www.21stcentech.com/headlines-french-italian-gmo-study-showing-tumors-rats-retracted/

It turned out that lab rats in general were prone to them, and the genetic line they chose to use was extremely prone to them to where it was guaranteed. After pressure the study was retracted, but it was already in people's heads.

2 points
 
by SolarAUalmost 4 years ago

Yeah of course it doesn't have to mean anything as it's one piece of research, but completely disregarding studies like this because I don't agree or wish it wasn't so is a bit willfully ignorant although interesting meta point but I suppose willful ignorance explains the widespread consumption of highly processed foods, alcohol, tobacco etc. despite huge amounts of research showing their direct connection with some of societies most common long term chronic illnesses.

9 points
 
by and_dont_blinkalmost 4 years ago

lol I'd ask you to reread what I wrote, as something went very wrong there. Best of luck!

-4 points
 
by noidontwanttoalmost 4 years ago

That was the impression I got too :(

7 points
 
by Foxer604almost 4 years ago

They literally fuxed up the first line:

.Menthol, through its cooling sensory effects, facilitates smoking and tobacco product initiation, which is reflected by the high popularity of mint/menthol-flavored E-cigarettes.

Menthol does not 'facilitate' smoking and tobacco product inhallation. And outside of enclosed systems like juuls where its only one of 4 possible flavours it's not all that popular. Walk into any vape shop and there's a hell of a lot more fruits and bakeries than menthol options.

When you start with a flawed premise minute one you pretty much have to question everything else.

9 points
 
by Lord-Graysonalmost 4 years ago

This comment is flawed

Facilitate means to make easier or less difficult. The context it is used is correct. Suggesting that the cooling effect of menthol as it relates to inhaling a tobacco product- makes it easier- for some people.

1 points
 
by Foxer604almost 4 years ago

Well unless it's a clear majority of people then you couldn't say that's why it was added. I've never heard anyone say that's why they have menthol in their juice. i'd need to see some evidence that it's a primary reason. They're not 'suggesting' it, they're stating it as fact.

1 points
 
by iowajoshalmost 4 years ago

>That can only be true if the flavors are "masking the harsh tobacco flavor" which we have seen in print before. And we know is bullcrap.

7 points
 
by WyomingCountryBoyalmost 4 years ago

No kidding. I smoked menthols almost 36 years and a LOT of people trying to bum a smoke would say "never mind" when they found out it was menthol.

3 points
 
by noidontwanttoalmost 4 years ago

It does facilitate those things though - it reduces the irritation caused. Plus it feels nice!

3 points
 
by Foxer604almost 4 years ago

I've never eperienced that - i like the taste in some recipes but i've never had it 'reduce irritation'. I don't even get irritation.

2 points
 
by BruceOfWaynesalmost 4 years ago

They're referencing actual tobacco products, not vapes. Those that are actually combusted cause far more irritation going down as they're burning far hotter than any vape ever could. That smoke is actually burning your soft tissue on its way down. Menthol not only soothes that irritation after it's occurred, but distracts from it while it's occurring making the consumption of said tobacco easier, or facilitating it.

This is also why Vaporub works so well when we're sick. It's soothing and/or numbing the irritation caused by the illness.

1 points
 
by 5Wi5Halmost 4 years ago

I agree with you that this is a flawed premise based on the wording they’re using, but most commercial vape juices I’ve seen also have an ‘on ice’ version. The ‘on ice’ versions seems to be the same thing with WS-23 added. So it is a popular option.

4 points
 
by ocolin381almost 4 years ago

I’d like to see this study done in another country not supported by big tobacco tbh.

3 points
 
by scottch_redditalmost 4 years ago

Yeah, I guess I'll give you that the article is well-written, after all, the author(s) are college educated, but that's it, I neither believe nor disbelieve it & none of us should, because it hasn't even been peer-reviewed yet, maybe the numbers are off, maybe it's intentionally or unintentionally biased. So in the form that it is in, it's nothing more than an opinion piece.

3 points
 
by FatBaldingWhiteManalmost 4 years ago

You got my upvote.

Just do a search on r/electronic_cigarette or r/Vaping and see how many times people have asked about "long term effects" (usually followed by "We don't know"). This study is by no means a smoking gun, but certainly good enough to say "we really need to look at this a little more".

You might get downvoted to hell on some other vaping subs, but considering how mixers have already grabbed the bull by the horns and published the flavor safety compendium, I like to think we're ahead of the curve.

1 points
 
by noidontwanttoalmost 4 years ago

Thanks, yeah, I didn't even post it in those other subs..

2 points
 
by Electronic_Cherriesalmost 4 years ago

Thanks for sharing

1 points
 
by Acyliabandalmost 4 years ago

No wonder the puff bars always felt like menthol. That shit was gross and not worth the money.

2 points
 
by noidontwanttoalmost 4 years ago

I've never tried one myself! It seems like the safe amounts of ws-23 according to this study are pretty low, I don't really understand the math that well though..

I will probably err on the side of caution and tune the coolant down though hah

I have had some pre-made juices that were like vaping an ice cube, where I got a brain freeze, I like my juice cold and had been mixing it that way.. kind of a bummer.

11 points
 
by kiswaalmost 4 years agoProud Sidebar Reader!

I'm not exactly amazing at maths either, but if you go with the lowest value of 5mg/kg bw, then if you weigh 150lbs (about 68 kg), then you'd have to ingest 340mg of WS-23 to hit the limit.

Let's say you use a 30% concentrate as 1% of a 30ml recipe. That's .3ml of the concentrate, which is a 30% solution, so .09ml of WS-23.

Assuming 1ml is equivalent to 1mg, which feels right but is probably wrong, then you'd hit the limit if you ingested 3,477.7777 batches of 30ml each, or about 113 liters of e-liquid.

So, yeah, you're probably fine.

If anyone wants to check my work and tell me if I'm full of shit, please feel free.

4 points
 
by TeslaDelMaralmost 4 years agoATF Developer

You're spot-on from my perspective. 1ml is not 1mg, you're right, it depends on the density of the solution in question. The "rough estimate" of WS-23s density is 0.9419mg/mL, so the "more accurate" number is 0.0846mg per 30mL of liquid at 1%.

1 points
 
by NuttyNana1almost 4 years ago

So by your calculations 1% should be fine?

1 points
 
by noidontwanttoalmost 4 years ago

The way I understood it was that it was much much lower than that. I honestly don't know hah

https://www.chemsafetypro.com/Topics/CRA/What_Is_Acceptable_Daily_Intake_(ADI)_and_How_to_Calculate_It.html

2 points
 
by Acyliabandalmost 4 years ago

I prefer a really nice hot vape. Cold is just off putting to me at this point. I never got into menthol due to that and it’s a cotton killer. If you put one drop on a RDA you’re tasting nothing but menthol lol

1 points
 
by flydelta9almost 4 years ago

Been using Kind Juice organic menthol, and while the cooling effect doesn't last as long, it's been non irritating unlike w-* (for whatever that's worth). In small doses it's a really good flavor carrier.

1 points
 
by Segontia18almost 4 years ago

Why would someone downvote you just because you link to a study? Vapers who reject or deny studies that discover potential health risks from vaping are just as biased and narrow-minded as the anti-THR extremists. We should be interested in the findings of such studies. After all, it's about our health. However, we have to look very closely at studies with negative results because of the amount of junk-studies that are published every day. Were the scientists objective, are the credible, who funded the study, was it a study with cell cultures or rodents, how many humans participated, what exactly was examined and by what means, etc..

To date, I know of 3 ingredients in liquids that can have negative effects if you inhale high doses of it. Coffee, cinnamon and vanilla (Dr. Polosa talked about it in a lecture). It wouldn't surprise me if menthol and cooling agents would belong to that group. But as with all other things it's the dose that makes the "poison".

1 points
 
by uncleKippalmost 4 years ago

Ah man, vanilla, really? That sucks. I love my custard & desert liquids.

1 points
 
by gorman42almost 4 years ago

Thanks for sharing the study. I'm not particularly into WS-23 and even for juices for which it makes sense to use... I usually stay at 0.50% maximum.

1 points
 
by Segontia18almost 4 years ago

One thing must not be forgotten: animals used in studies are extremely susceptible to countless diseases. These aren't healthy animals from the wild, but a highly specialized breed to which the development of various diseases has already been "programmed" into the genetic code. In addition, not every finding is transmissible from rodents to humans. To nicotine, for example, people react totally differently than mice or rats. That's why results of nicotine studies with mice can't be transferred to humans.

However, I would be careful when it comes to cooling agents. There might be something to it. The liver damage doesn't sound very plausible, but our lung tissue, the palate or trachea, etc. could react with inflammation to menthol or ingredients derived from menthol. I have to ask Prof. Bernd Mayer, a toxicologist (and vaper), what he thinks of this study. Nevertheless, I am sure of one thing: it depends on the dose. As with everything we consume.

-3 points
 
by sa250039almost 4 years ago

I dont know how anybody uses that stuff anyway, it tastes like ass

-2 points
 
by ANDYP300almost 4 years ago

I hate the mint/menthol/cool stuff. At most a single drop of mint concentrate in 50ml mix is all i can tolerate. I think i must be super sensitive to that taste.

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