Popcorn’s distinctive, delicious and pervasive buttery smell instantly floods me with memories of movies, movie theaters and great big glass containers crammed with aromatic goodness. I was concerned to learn of something called popcorn lung a few years ago, and the new association of the smell of fresh popcorn with a debilitating disease has somehow tainted my golden memories.
In 2015 and 2016, some sensational articles in publications like Mother Jones and the Huffington Post publicized a Harvard School of Public Health report which stated that the majority of 51 vaping e-juice in their laboratory test contained the chemical diacetyl. The study pointed out that diacetyl had been linked to cases of a severe, irreversible respiratory disease called Obliterative Bronchiolitis (OB).
While the study pointed out factual findings, some of the media managed to miss the point of the study completely. Their articles failed to point out that ‘normal’ cigarettes also contain diacetyl, in quantities far greater than that found in the e-juice Harvard tested. Cigarettes contain over 100 times more diacetyl than the levels found in even the best e cig products, but previous tobacco studies concluded that the level of diacetyl in cigarettes was not enough to cause popcorn lung in smokers.
Headline-chasing and irresponsible reporting has created the impression that vaping is more dangerous than smoking and inevitably leads to popcorn lung. Michael Siegel, a Boston University professor, summed up the controversy by saying that the media often create “a scare by omitting a key piece of information” and that such media tactics can lead to “perverse public health outcomes.” Sensational headlines sell more papers, but we should never forget two important facts:
However, we need to find a way to get our intake of nicotine without exchanging one danger for another, and that is why the Harvard report is an important piece of the puzzle, though it does not contain all of truth. Britain’s National Health Service (NHI) has published a more balanced report on the matter, which is sure to be updated as more research results become available.
Diacetyl is a chemical used extensively in the food industry to mimic a rich buttery flavor in candy, microwave popcorn, and many other foods. The FDA approved it as safe for consumption as a flavor ingredient, but inhalation of high levels of airborne diacetyl can be harmful. The Occupational Safety and Health Administration (OSHA) recommends air sampling, closed systems and air purifying respirators in manufacturing plants, and in 2011 recommended a short-term air exposure limit of 25 parts per billion (ppb). Diacetyl has been found in vapor created by a number of electronic cigarette flavors as we reported in our “Truth about Diacetyl” article back in August last year. Acetoin and 2,3 pentanedione are other potentially harmful substances also found in e-cig vapor.
The disease has been informally termed “Popcorn Lung” because its first notable appearance was in a microwave popcorn factory in Jasper, Missouri, where workers regularly inhaled the artificial butter flavor diacetyl. After eight former workers at the Gilster-Mary Lee popcorn plant had developed Bronchiolitis Obliterans, the National Institute for Occupational Safety and Health (NIOSH) recommended respiratory protection for workers in microwave popcorn plants and the flavoring manufacturing industry.
There are several causes for this rare disease: Collagen Vascular disease, viral infection e.g. HIV, transplant rejection in some organ transplant patients, emergency oral administrations of activated charcoal, drug reactions and more. However, this usually rare disease gained notoriety due to proven links with exposure to toxic fumes like ammonia, mustard gas, ozone, certain industrial dyes, diacetyl, nitrogen, sulfur dioxide, chlorine, phosgene and several other chemicals.
Bronchiolitis Obliterans is a disease that causes inflammation of the tiny bronchioles (airways) of the lungs. The inflammation results in scar tissue formation in, and obstruction of the bronchioles, with severe shortness of breath, a dry cough, wheezing and tiredness. The prognosis is poor. Treatment may include immunosuppressive medications and corticosteroids to slow the inflammation, and a lung transplant. It is a severe, usually fatal disease, but it is fortunately rare.
Initial descriptions appeared as far back as 1956, but the first explicit description only appeared in 1981. It is not new, but increased incidents implicate modern industrial life due to the definitive links between Popcorn Lung and exposure to certain toxic fumes.
Industry bodies have warned that nylon flock workers who use polyamide-amine dyes are at risk, as are battery workers who inhale thionyl chloride fumes, workers at flavoring manufacturing plants and employees who are exposed to flavors such as diacetyl in food processing plants.
A minute quantity of Diacetyl is used to obtain a buttery-tasting vapor in some candy and creamy-tasting vapors. Minty, citrus, and spicy flavors do not usually contain diacetyl, whereas most vanilla, chocolate, and creamy flavors may contain it. Acetoin and 2,3 pentanedione (two other potentially harmful substances) sometimes replace or complement diacetyl. These are all legal, if potentially dangerous, additives and may be listed simply as ‘Natural and Artificial flavoring’.
If you are concerned about it, ask your manufacturer for a list of ingredients. It may be better to avoid diacetyl, but keep in mind two (in)convenient truths:
Whatever flavors you choose, always purchase only from reputable distribution and manufacturing companies. If possible, choose a brand that can offer independent testing results that verify their claims. It is critical that manufacturers follow good manufacturing principles and quality control.
Smokers who turn to vaping to quit smoking would be inhaling diacetyl at levels far, far lower than the amount in cigarettes. That makes the danger less, not more. However, though vaping has been described as ‘up to 95% safer’ than smoking, it is possible that future research will prove that figure to be slightly optimistic. Users have a personal responsibility to keep up with research on the safety of vaping.