Free access article discussing the cell toxicity of eliquid flavouring

Free access, lots of free access publication linked. Not terribly convinced by methodology but not a specialist.


More B.S.

The article states:
“To obtain cell-free ROS assay for “consecutive flavors, the cells were aerosolized two puffs per e-liquid flavor, one flavor at a time for 10 min.”

Funny thing when I vape, I don’t aerosolize, I vape. I also don’t do it 10 minutes at a time. Anything I inhale when I vape get distributed through my entire body not concentrated to a handful of cells.

Geez, when will they actually test with similar conditions to what we vape?? Bunch of villagers with pitchforks if you ask me.


I mentioned that the methodology did not convince me, but standard representative methodologies for toxicity are sometimes counter natural. I’ll pass on the article to a couple specialist friends in pharma/cell biology and report if they come up with something.
The conclusions at the end are interesting regarding multiple flavouring.


The conclusions at the end are interesting, but not accurate imo


Admittedly, I only skimmed this but one question I didn’t see answered.

“Conclusions: Our data suggest that the flavorings used in e-juices can trigger an inflammatory response in monocytes, mediated by ROS production, providing insights into potential pulmonary toxicity and tissue damage in e-cigarette users.”

How does this tissue damage compare to smoking cigarettes? How does it compare to the pollution in most cities?


That is my only true concern as well , I do think that most all of will agree that vaping is a harm reduction over tobacco. I honestly just want to know if it is safer than smoking , so many of the ones doing these studies have a financial gain in mind.
I have not smoked in five years and I have vaped 10-30ml of juice every day during that time.I feel better now than I did five years ago so I guess for now I will continue to vape!


They can’t argue with it being so much safer so they want to attack the flavors I guess.


I don’t think anyone argues that vaping is much less dangerous than smoking, the benefits are pretty obvious for the users even in the first days.
I don’t think we should be too defensive about toxicity analysis of what we inhale even if it is much less harmful than something else.
Say, if it turns out that the cinnamon flavour compound does represent a genuine risk, not just the relative one highlighted by the study, it makes sense for flavours to be tested for it and people can choose to expose themselves to it or not.


The pollution angle is interesting, a lot of the avoidable harmful pollution comes from residential wood burning, and a good proportion from transport. The effects thereof seem to be pretty difficult to quantify.


I agree and thank you for posting this. Information is power as they say, I realize after reading my post that I was like damn the torpedo’s full steam ahead. I wish we had more studies on all the products we use daily vaping. I just no longer tend to trust anything these days that I see published , everybody has an agenda it seems and very few actually give a tinkers damn about any ones health it seems.


No offense taken, I had a similar reaction to the lack of justification of the methodology and it’s comparison to real life exposure levels, as well as the relevance of the cell experiments on actual subject health.


Honestly the test means absolutely nothin* to me. It set up with one goal in mind show the ecigs are bad for you… doesn’t take a rocket scientist to know that ecigs are bad for you… but it also doesn’t take a rocket scientist to know they are better than cigarettes .

Until they do side by side test of ecig versus cigarettes versus non smoker in LA( I think that’s a polluted city). Theses test that say ecigs are bad are just that propaganda attacking what I consider a safer alternative to cigarettes.

Do I have any proof that ecigs are safer. Nope, only my personal observations. Smoking cigs couldn’t walk up a single flight of stairs… after switching to ecigs I can walk up stairs with no problem dig ditches all day long, and oh yea at night momma is happy.


This article has all the hall marks of a classic piece of “junk science”… The hangers-on at low quality research labs in various colleges and universities around the country shot gun out tons of this crap hoping to snag some of that big pile of Federal dollars in NIH research grants. It always helps if the subject matter is currently on the radar of federal agencies.

Tip offs to junk science papers are usually similar. Like extravagant mistakes or total misrepresentation of cause and effect. In this case we seem to have jumped from the analytical lab chemistry to statements like: "Findings in our study (…) imply that (,) . E-liquid flavoring chemicals and other constituents must be tightly regulated to minimize the risk of lung disease especially among teens.

Other typical junk science tip-offs is “round robin” cites to previous experimental results from the same group of investigatiors. As well as cites to previously discredited papers in the literature. The many cites used in this paper to things like diacetyl, 2, 3-pentanedione, is classic mumbo jumbo bate and switch.

Also real scientists ask the right question when trying to get the right answer. You are just playing games if you cherry pick 5 compounds already known to have some degree of toxicity then pretend that you can expand any result you get from that contrived experiment with those compounds to answer a greater question like “Is the flavoring agents generally used in E-Liquid in fact toxic at a significant or meaningful levels in the general population?”,

They are not fooling any real chemist that reads this, for example coumarin. which is a common industrial chemical, actually a Benzopyrone is produced in metric tons world wide for many uses. If they are so worried about its “toxicity” they would be better advised to write a paper on that hazard, rather than picking on some guy that is just trying to quit smoking.

I could go on for pages about “junk science”, but it is a subject, that sadly, has taken over Washington DC. It is one of our greatest unseen enemies, and is much more dangerous than all the E-Liquid on the planet.

for more about junk science and vaping see:


Thank you for posting @SuperFrog well done, wether or not it’s misleading or wrong we have to know potentially harmful claims!
Let’s have a look at it:
“We hypothesized” and that’s one… and we start with an assumption…

“The number of non-cigarette smoking youth who use e-cigarettes has tripled over the past years” not absolutely true, that assumption has been proven wrong, I’d worry about IQOS or similar products leading to cigarettes, not vaping.

“With the declined consumption of cigarettes, e-cigarettes are advertised as a healthier alternative” Not true or proven, third world countries are banning vaping in favour of smoking cigarettes there’s no “declined consumption of cigarettes” as such, vaping is making that decline!

“Studies have shown that e-liquid aerosols contain significant levels of toxic compounds, such as aldehydes and acrolein that are detrimental to e-cigarette users” If they keep on doing tests when the cotton is burnt,mesh gone, res exausted, it’s quite normal and we all know that at extremely high temperatures the res/cotton-mesh releases aldehydes and acrolein, but in my life I never saw a vaper vaping burnt cotton or a res with hot spots for more then, shall we say 2 seconds? (and it’s a lot!)
But I really like to see those researchers vaping with burnt cotton or an Hotspot for ten consecutive minutes :joy::joy: :joy:

We, as mixers (they are talking about mixing flavours…) all know that: acetoin, diacetyl, pentanedione, cinnamaldehyde are the chemical flavours under scrutiny and we are all well aware that at high percentages, either in a single or mixed together, for a very long time “COULD” be dangerous (clearly not comparing to cigarette smoke!)

So what have we got, a study that mostly refers for assumption to other studies not done by them and some of them have been proven to be wrong.
We’re still far far away from a real health assessment with real PV’s with real people, and compared to cigarettes.
Why don’t they show and advertise the percentage of people that have quit smoking whatever burnt tobacco product in favour of vaping… but that’s another story.


Maybe you’d prefer this one: the abstract thereof being very close to what you are saying

tl;dr; many studies use bad methodology. Overheating/dry hits seem to generate bad compounds and some studies seem to exaggerate risks to fluff themselves.

My main interest in sharing this link is the sheer amount of full text linked materials


@50YearsOfCigars I agree, and it does have many of the tell tale signs…

The e-liquid manufacturers market these liquids with alluring names, such as Cotton Candy, Oatmeal Cookie, and Tutti Frutti that are more appealing especially to young adults (Allen et al., 2016).

Vaping exposes these flavoring chemicals to the lungs when the e-liquids are heated and inhaled with a similar mechanistic pathway as the inhalation of chemicals at microwave popcorn factories and coffee roasting plants (Bailey et al., 2015).

Just TWO that stood out to me thus far. I’m SURE vaping isn’t safer than doing nothing, but when I start to see/feel/sense a slant, I start to loose faith in the integrity.

@SuperFrog Thanks for the linkage none the less, will read it in it’s entirety.


@Iv3shf the points you and @SessionDrummer bring up are all part of the “mantra” of the anti-smoking / ant-vaping zealots. They have a well developed play book of junk science that is being used, bought and paid for, by NIH grants and well funded non-profits. I fully understand that the average man on the street, the average vaper does not understand how, and is very confused what to make of these “papers” that are presented as “scientific research”

If you are not in the world of research, if you are not a working professional in the world of academic ‘research’, then it is can be very hard to wrap ones head around. all this mis-information, and to wind up totally confused and start asking “is this real science, or is it something else?” But realize that scientists are people too, with personal points of view, personal value systems, and families that must be fed, so yes, some sellout, and all science is not “good science” There is such thing as “bad science”, and in the subject of vaping, that bad science is everywhere.

For a very good series of videos on this, to help you understand how and what bad science is, how it is created, how it takes over ‘good science’, I strongly recommend that all vapers listen to the excellent work of Brent Stafford at RegWatch(dot)com. Brent is one of those people that can bridge the gap and explain complex things that most of us never get near or touch in our lives. He does it all in very easy to listen to, very well produced short videos.

Please listen to his excellent series on Science and Vaping at:
31 videos 3 Dec 19, 2017

and if I had to pick just one or two from the above excellent list, if you are short of time, but still want to understand the nuts and bolts of Junk Science and it how works: listen to:



@50YearsOfCigars ^^^^^ That nails the point home, and is what “they” count on IMO.


Funny, after that article, another one came out stating that coffee could cause cancer. I’ve vaped for 4 years now and haven’t grown horns yet. These companies or people make half assed claims filled with no real facts just probability.


Edit: everything causes cancer even water