Harvard Study Finds E-Cigarettes Contain Dangerous ‘Popcorn Lung’ Chemicals


Researchers at Harvard T.H. Chan School of Public Health, have found that flavoring chemicals used in electronic cigarettes and their refill cartridges can cause bronchiolitis obliterans, also known as “Popcorn Lung”, a rare irreversible respiratory disease eight workers in a Missouri microwave popcorn plant reportedly developed in 2002.

The US Occupational Safety & Health Administration describes bronchiolitis obliterans as a condition which develops when small airways become inflamed and scarred, resulting in the thickening and narrowing of the airways, leaving users with a cough and shortness of breath.

In their study, published in the journal Environmental Health Perspectives, the researchers tested 51 types of flavored e-cigarettes and liquids sold by leading brands for the presence of diacetyl, acetoin, and 2,3-pentanedione, two related flavoring compounds that the Flavor and Extract Manufacturers Association lists as “high priority”, i.e., they may pose a respiratory hazard in the workplace.

At least one of the three chemicals was detected in 47 of the 51 flavors tested. Diacetyl was detected above the laboratory limit of detection in 39 of the flavors tested. Acetoin and 2,3-pentanedione were detected in 46 and 23 of the 51 flavors tested. The Harvard researchers found that the heating, vaporization and inhalation of flavoring chemicals in e-cigarettes makes smokers’ exposure similar to that of workers in the microwave popcorn industry.

“Recognition of the hazards associated with inhaling flavoring chemicals started with ‘popcorn lung’ over a decade ago. However, diacetyl and other related flavoring chemicals are used in many other flavors beyond butter-flavored popcorn, including fruit flavors, alcohol flavors, and, we learned in our study, candy-flavored e-cigarettes,” said lead author Joseph Allen, assistant professor of exposure assessment sciences.

The study—which was funded by the US National Institute of Health and not by any tobacco lobby—focused on the chemicals used to flavor e-cigarette liquid and not on the harmful effects of nicotine. As a result, even if users vape with nicotine-free liquid, they could still end up with popcorn lung. In other words, e-cigarette users, who believe the products help them transition away from smoking regular cigarettes, may also end up causing significant damage to their lungs.

“Since most of the health concerns about e-cigarettes have focused on nicotine, there is still much we do not know about e-cigarettes. In addition to containing varying levels of the addictive substance nicotine, they also contain other cancer-causing chemicals, such as formaldehyde, and as our study shows, flavoring chemicals that can cause lung damage,” noted study co-author David Christiani, Elkan Blout Professor of Environmental Genetics.

The study evaluated 7,000 varieties of flavored e-cigarettes from three large cigarette companies, one large e-cigarette company and three e-cigarette distributors. The researchers concluded:

“Due to the associations between diacetyl, bronchiolitis obliterans and other severe respiratory diseases among workers inhaling heated vapors containing diacetyl, urgent action is recommended to further evaluate the extent of this new exposure to diacetyl and related flavoring compounds in e-cigarettes.”

Are e-cigarettes a gateway for new or underage smokers? Do flavored e-cigarettes attract younger smokers? Can e-cigarettes reduce the incidence of cigarette use? Are e-cigarettes less damaging to health than smoking tobacco?

A study that was published in the August edition of the Journal of the American Medical Association, found that ninth-graders who used electronic cigarettes were more likely to smoke cigarettes, cigars or hookahs than peers who never tried the battery-powered devices. However, during the same month, Public Health England concluded that, on “the best estimate so far”, e-cigarettes are about 95% less harmful than tobacco cigarettes. In addition, Public Health England also declared that vaping is safer than smoking and could lead to the demise of the traditional cigarette.

We acknowledge that diacetyl shouldn’t be used in e-cigarettes, but equally diacetyl is found in cigarettes at very significant levels, so obviously there is a harm-reduction aspect to switching to e-cigarettes,” said Tom Pruen, chief scientific officer for the UK-based Electronic Cigarette Industry Trade Association.

In 2014, the Centers for Disease Control and Prevention report found that 2.5 million middle and high school students used e-cigarettes, and that teenage use of electronic cigarettes had tripled in the last year. Youth use of e-cigarettes also surpassed youth cigarette smoking. In June, a poll of 5,679 Americans, conducted by Reuters, found that 75% of people who use electronic cigarettes or other vaporizing devices continue to also smoke traditional tobacco products.

Diacetyl is found naturally in butter, beer and other foods, and it is added to baked goods, candy and snack foods to give a buttery or creamy taste. Although it is considered safe to eat, inhaling it has been linked to a number of severe respiratory diseases. What are your thoughts? Please share in the comments section below…

This Article (Harvard Study Finds E-Cigarettes Contain Dangerous ‘Popcorn Lung’ Chemicals) is free and open source. You have permission to republish this article under a Creative Commons license with attribution to the author and AnonHQ.com.

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  1. This has already been debunked and taken care of as irresponsible journalism. Please look up Dr. Farsalinos and his work regarding e-cig studies.

    If they are so dangerous, why are so many other health organizations (who don’t have the ties to big pharma and tobacco payout settlements like the USA) in such support of them? Please, do all the research before just re-publishing yet another bad press story.

  2. The traced amounts of the chemical that leads to popcorn lung is .5 percent in most eliquids. But that is less than the 98 percent in a regular cigarette. In this country alone cigarette company’s dominate stock markets and have a major role in this country’s budget. Tobacco is a huge money maker since day one. Think about it people…

  3. What about all the crap they are dumping in the air people are stupid the air you breathe is killing you but oh well if these things are so dangerous why are the company’s not shut down just like with cigarettes the government collect the tax money they should be held liable stupid sheeple

  4. Unsubbing.
    This page is one i nwver would have thought would jump on the ‘vaping is death’ bandwagon without first doing research.
    Shame anon shame.
    Just part of MsM now i guess. Glad to know you cannot be trusted to report facts.

  5. I love how people like @jonnamiller67 read an article and plaster it all over twitter. She is your typical uneducated moron who believes everything she reads. Her tweets are all pointless banterings where her negative attitude shines. People like her make me sick, but also make me realize that’s why we need to educate people. We need them to stop spreading lies…

  6. I have used an e-cigarette since Dec 16/14. I have not had a real cig since. As of midnight Jan 1/16 I have diverted $4370 from tobacco while spending $500 on its replacement. Follow the money. The only way to quit after smoking a pack a day for 48 years. I am not an ex smoker because of Nicotine I am a non practicing smoker that has spending money again.

  7. I have warm hands and feet again. No tar or the other 40 plus cancer causing chemicals that I inhaled daily. If there is a possibility that there might be chemical reactions when vaping I am positive the smoke from a cigarette is much worse. From the pictures I have seen living in Beijing is also worse, sorry China, than vaping. I am keeping my vaping habit and my new found spending money.

  8. Where is the rest of the story? Like the fact that cigarettes have 110 percent more of the chemical? Despicable irresponsible reporting should be punishable by law. Can we believe anything from this news outlet?

  9. The industry is self regulating. When we discovered these chemicals were present, we stopped buying e-liquid that contained it, lowered the levels, and changed recipes to no longer use the flavorings that contained them.

  10. Two word rebuttal… Harm reduction.

    100% healthy? No.
    Less harmful? Yes.

    Need for regulations? Yes, just not ones that only allow big tobacco to crush it’s main competition.

    Manu gainfully employed in the industry, and many small businesses because of vaping.

    • and a perfect answer- Doug– the key–(((*(*Need for regulations? Yes, just not ones that only allow big tobacco to crush it’s main competition)))

  11. Harvard didn’t mention that cigarettes contain between 100 and 750 percent more diacetyl than the highest ecg ‘cartridge’ in their test. Cigarettes weren’t mentioned at all. Cigarettes have never been determined to cause popcorn lung.

    I really wish that so-called journalists would actually research instead if being spoon-fed headlines. Where did critical thinking go?

    Forbes just published an article about e-cigarettes that you should read.


    Stop all the misinformation please. Ecgarettes can become the biggest health intervention in our history.

  12. You can not compare the amount of chemicals that a person working at a popcorn plant inhales compared to the amount a person who vapes inhales. There are only trace amounts of the chemical in e cigarettes compared to that of a popcorn plant. Eliquid manufacturers are starting to make there own flavorings specifically made for vaping . What really posses me off is all these years that cigarettes have been killing people and no one seems to want to ban cigarettes but they want to ban the only thing that has proven to help smokers quit smoking tobacco for good. I am one of those people I smoked for over 14 years and tried everything there is in the market and nothing worked. The same day that I tried vaping I quit smoking and never looked back .The media wants to make the Vape industry look like a bunch of irresponsible money hungry liars. Everyday Vape companies are working on new ideas to combat what is going on we are very aware and are very responsible people that care for the health of the public unlike big tobacco companies

    • I’m so with you. I can’t stand all the lies. Ive been smoking 25 years. After the 1st day my lungs felt way better and cough stopped. They are a bunch of criminals! Trying to kill us.

  13. Thus is Bullshit, a more recent study shows that cigarettes actually expose smokers to popcorn lung at higher rates than ecigs and that levels in non smokers was higher in people who smoked ecigs…….go figure!

  14. Wow..so I guess you really don’t care about your rep for being a journalist I suppose…you do know that my 15 year old daughter can write a better story (yes…a story) because that’s what this is…try doing proper research and stop scaremongering. My god. I mean there are how many vapers in the world now? Over 3 million? And there hasn’t been a single health issue? Oh…didn’t you do the research on that? It seem all you’ve done is copy and pasted a crap ton of links and you’re acting like a parrot…you know…the bird that just repeats what it hears…kind of a brainless creature actually.

  15. I am so disappointed in Anonymous! You were heros to me: champions for truth – based knowledge & informed decision making. U stood up for WikiLeaks. But now you are collaborating with a multinational conglomerate of corporations suppressing tobacco harm reduction to ensure the massive profits from tobacco addiction. Your misinformadion is ensuring the slavery to tobacco addiction as well as the inevitable smoking related diseases resulting in human suffering. Shame on you! Shame!

  16. I have been vaping over a year now,I’ve not had any viruses, no chest infections, I could hardly breathe at times, I had a smokers cough for years, all gone since vaping, so thank you I’m keeping vaping, and I’m reducing vaping liquid strength. ALL GOOD!!

  17. I am a former smoker of 15 years that quit by using an ecig. I know what my body is telling me and that is the ecig is better than cigarettes. Is it harmful for me?… Sure it is, and anyone that says otherwise is stupid. Nobody can say these things are perfectly safe. But when compared to actual cigarettes…. I’d have to say the ecig is the lesser of 2 evils. It’s like the difference between a bottle of vodka and a bottle of Pepsi. Yes both bad but we know which one is less bad.

  18. AZAP that article is 100% stupid. Yes cigs are worse but that doesn’t mean vaping is good.

    “Do some damn research, already unfollowed your page on Facebook because of your careless propaganda on this subject…”

    What by quoting one really crappy article? What propaganda? You sound like a 12 year old politics student

    “You should be ashamed, expect repercussions.”

    Hahaha what repercussions? What are you going to do? You mean like unfollowing on Facebook? Wow. I bet they are terrified. Try giving a shit about something that actually matters in the world.

    Yes Ryan but “lesser of two evils” means that both things are evil. Just bc one is a lesser evil, it doesn’t change it to being a good thing, so you should have neither. You shouldn’t think “well this is less evil so I’ll have loads of it”

    • There’s no evidence whatsoever that Diacety/Acetoin even causes popcorn lung in vapers, some people have been using it for almost 10 years now and have no symptoms of it whatsover, not that I’m defending smoking but the average cigarette has 110 times more diacetyl than ENDS liquid and guess what? No popcorn lung…

      The people in the factory were exposed to a powder form of it at concentrations up to thousands times higher than what was found in this study…

      If people are going to be addicted to nicotine… I’d much rather see them vaping than be on a path that leads to cancer, ENDS are a harm reduction tool, not comparing them to what they are reducing the harm from is junk science..

      To date, diacetyl is the only controversial thing found that could potentially harm people who use ENDS (Electronic Nicotine Deliver Systems), It could be completely removed from the industry with some minor legislation…

      As for repurcusions, I share a lot of Anon stuff from here, my direct audience is about 5000 people, how far it reaches is about 10-12 thousand… Anon is losing a lot of views because of this…

  19. I can guarantee that everyone commenting on what a rubbish article this is in terms of it’s evidence base is an e cigarette user. We used to think that smoking cigarettes wasn’t bad for us and that wasn’t too long ago either. Vaporising chemicals and inhaling its produce is never going to be a good thing. I’m unsure as to why no one else can grasp that. It does not matter how much worse smoking cigarettes is for you. If you want healthier lungs, don’t smoke a thing.

    • That simply is not an option for some people… Have you even seen a person with throat cancer smoking through their tracheotomy hole????

      I’d much rather see people switch to vaping, lowering the risks associated with nicotine addiction then work on that addiction than them continuing to smoke until they die from it….

      what are these chemicals you speak of anyways? Diacetyl? if that’s the only problem with vaping it could be regulated out of the industry…

  20. I too am shocked and dismayed by this article. I am involved in the industry on a level that requires me to be informed of the facts and statistics as well as laws and regulations. Here is an article that helps shed light on the truth. http://www.ncbi.nlm.nih.gov/pubmed/24635357
    There were many pertinent factors not considered during the investigation in the “popcorn lung” incidents; it further goes on to report that the diacetyl concentration levels were much higher because they were in a powder form /20662421 (read article). Although I agree that there should be some regulations, the whole premise of the article that was initially published, was to scare people. They also failed to mention all the e-liquid companies manufacturing with lab tes results showing they are FREE of harmful substances.

  21. This is dumb because I had “uncontrollable” coughing from smoking those
    cheap ass cigs from the indian reservation or any other cigarettes for that matter. I quit them and went to smoking e-cigarettes, (the e-liquid I actually mix and blend myself) and my cough is completely gone and I am breathing better.
    The flavors only contain “diacetyl” if you buy the already made flavors that people
    added that stuff to it. The mixtures I make don’t contain that stuff. It
    is strictly flavor concentrate(that can be added to food), PG, VG, and a
    nicotine concentrate. None of which containt diacetyl or any other
    added chemicals. The “only” bad thing that is in my mixture that could
    affect me is “nicotine” which is already proven that it’s bad for you.
    I’ll take my risk with only nicotine instead of inhaling everything else
    that comes out of a regular cigarette.

  22. Funny how every one condoning this Harvard research. .no its not ‘feeds garage’ research is defending their esmoke. The study does not mention cigarettes because that’s not what the study was about. .have any of you ever read an actual research paper? I have been vaping butter rum flavor for over 3 years now. .yes ..my teeth are whiter. .my cough and phlegm are gone. ..but you know what? I was just tested for COPD- emphysema due to my new found shortness of breath. ..this article scares the hell out of me and motivates me even harder to try sticking to gum only when I wake up tomorrow

  23. I used to smoke and after 25 years of tar and all the other crap I was breathing in I just stopped smoking , I did not need these E-things and I just don’t see why anyone would, if you want to stop smoking just stop smoking !! these E things are a waste of money just like normal cigarettes and for the record I believe a research paper from Harvard over any of the bedroom scientists that have left stupid comments here !

  24. BULLSHIT. This is not anonymous, who control this article
    This is the government and medical company’s . Because we shall only buy their products and just that. And nothing else should be aloud for any one.


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