E-Cigarettes and Popcorn Lung Disease
WHAT IS THE NEWS STORY
The latest trend in smoking has been electronic cigarettes, or as commonly known e-cigarettes. They have been promoted as a much safer alternative to smoking regular cigarettes, but of course, there’s the old saying that goes, “if it’s too good to be true...then it probably is”. It turns out the Harvard School of Public Health decided to do a study on e-cigarettes and the results are startling. It looks as if they may not pose the traditional cigarette threat, but they pose a different one altogether.
WHY THE STORY HAS MISINFORMATION
The disease popularly known as 'popcorn lung' is medically known as bronchiolitis obliterans (BO). According to the American Thoracic Society, BO is a disease characterized by the presence of shortness of breath, decreased exercise or activity tolerance and endurance, fatigue, and a cough that may be coincidental or not with increased mucus production. BO is mostly related to patients that underwent a lung transplant; it is related to acute rejection, though it is implied that there are other risk factors and causes related to this disease, like gastroesophageal reflux disease (GERD) and infections by pathogens like Pseudomonas aeruginosa, Cytomegalovirus (CMV), Aspergillus, respiratory syncytial virus (RSV), parainfluenza, and influenza to name a few. Another previously unknown and highly controversial factor, for 30-years until the 2000's, was the occupational exposure to diacetyl, with delays in its recognition attributable to several causes.
According to a 2016 study, there are more than 7,000 e-cigarette flavors currently on the market. Although knowledge about the presence of flavoring chemicals in e-cigarettes is limited, some voices raised their concern about the presence of the flavored chemical diacetyl because of its supposed association with this disease. This study found out that diacetyl was detected above the laboratory limit of detection in 39 of the 51 flavors tested, ranging from below the limit of quantification to 239 μg/e-cigarette. Taking these levels into account, other researchers have measured the concentrations of diacetyl and 2,3-pentanedione in mainstream cigarette smoke at levels hundreds of thousands of times higher, yet traditional cigarette smoking is not associated in any way or form with “popcorn lung”.
Other studies point out that coffee shop workers and customers are continuously exposed to diacetyl during the preparation and consumption of unflavored coffee. This is an important affirmation since no relationship between coffee shop workers and serious respiratory disorders has been observed, questioning its relationship with bronchiolitis obliterans.
Regardless of the presence of diacetyl in certain flavors of e-cigarettes, present studies only offer evidence that points out that the flavoring chemicals present in e-liquid/e-cig aerosols may lead to pulmonary inflammatory responses as a result of long-term exposure. Future studies, using novel in vitro and in vivo models, are needed in order to determine both the short- and long-term consequences of inhaled flavoring additives on lung and oral health since they are not well documented. In fact, FDA deems diacetyl as safe for human consumption, and current EU regulations regarding exposure to diacetyl consider it legal for use as a flavouring substance. However, researchers believe that determining the consumption patterns of users of e-cigarettes should be an interesting topic of investigation, since there is no real way of assessing the exposure to the chemical without objective data about this parameter.
Some concerned voices call for coherence before making any affirmation about the role of e-cigarettes in the pathogenesis of bronchiolitis obliterans, since its relationship with this disease is still open to debate. Ironically, suggesting that e-cigarettes are potentially dangerous could actually lead to higher exposures to already proven dangerous chemicals in the smoking population if smokers decide not to switch to e-cigarettes due to as yet unfounded health concerns.