By Mark Gold, MD
The Centers for Disease Control (CDC) recently issued a warning about vaping following a multistate outbreak of severe lung problems linked to the use of electronic cigarettes.1 According to the CDC, there are, as of September 6, 450 reported cases of possible vaping-linked lung problems across 33 states and 1 territory, resulting in 6 deaths.2 Officials have not identified a specific e-cigarette product as a cause of the illnesses, meaning that various devices on the market could be contributing to this alarming pattern. Patients admitted for lung problems report difficulty breathing, fatigue, fever, nausea, and vomiting. Somehow, to proponents and purveyors of e-cigarettes, the very idea that vaping could be dangerous seems to have come as a surprise.3
The CDC updated its warning to suggest that e-cigarette and vaping device users refrain from using the products at all during the course of its investigation. It has also warned against buying counterfeit or street vaping products, including those with THC or other cannabinoids, and against modifying e-cigarette products. Moreover, the CDC urges youth, pregnant women, and adults who do not currently use tobacco products to refrain from using e-cigarette products, and encourages individuals who smoke and want to quit to use FDA-approved medications instead of e-cigarettes. Some health officials and experts believe that street vaping products with illicit or tainted substances may be behind the outbreak of lung problems, but no one can be certain at this point. Some patients have reported using vaping cartridges with THC or cannabinoids, but others have reported using different vaping cartridges without such substances. Most contain ingredients not generally tested for chronic inhalation in humans, and, to make matters worse, they can become contaminated in ways detrimental to respiratory and heart health.4 It is unlikely that any substance you inhale has been tested for safety for weeks, months, or over the long haul. But inhalation from vaping has effects on the lungs that are dramatic, can be easily seen on imaging5, and do not seem easy to reverse. Tobacco smoking in the English colonies of North America started early and peaked in the U.S. in the 1960s and 1970s, credible evidence proving its causal links to cancer, emphysema, and bronchitis emerging only over a century after its explosive growth and wild popularity.6 Why would boosters and defenders of today’s e-cigarettes, looking back at this history, believe that research would come to indicate the product’s benefits for the lungs, or for the respiratory health of those they may expose to vaping?
While experts and officials will continue to study this outbreak and may identify particular illicit substances as the culprit, the headlines have naturally raised questions for individuals who vape about long term consequences. What we know about cigarette smoking is bad enough, but there are few surprises. Here, we’re in uncharted territory. Yes, the FDA and other agencies will look at the broader health and safety of e-cigarette products and devices, but in the meantime, users will need to be evaluated and hope that their own lungs are not compromised in ways that only become clearly understood after they stop, or years down the line. While receiving considerably less media coverage, journalists recently found that the FDA began investigating vaping-associated seizures after some users of JUUL, the top-selling vaping product in the U.S., submitted claims of seizures to the administration’s safety portal.7
It is important to note that Research You Can Use previously observed that there is not yet enough evidence to conclude whether e-cigarettes are suitable for smoking cessation. Some researchers now suggest that vaping nicotine may not be safer than smoking tobacco cigarettes.8 More recently, the FDA has agreed that JUUL’s claims of comparative safety are unproven.9 Other new studies have looked at the relative health of ingredients in some e-cigarette products, and the effects of vaping on the vascular system. The truth is that it’s risky and scientifically invalid to start from the premise that drugs are safe until proven dangerous. It reminds me of cocaine being touted as safe, or non-addicting, or even as “the champagne of drugs” until the aftermath of widespread use in the 1970s and 80s demonstrated that it was highly addictive and led to heart problems, brain damage, and other diseases.10
What did these studies find?
One study, led by Yale’s Julie Zimmerman, found that chemical interactions in some of JUUL’s inhaled liquid nicotine mixtures yield unanticipated new chemicals that can cause breathing problems. In this study, researchers created a machine to trap JUUL aerosol and investigate its chemical composition. They found that the alcohols hosting flavors and nicotine in JUUL’s e-liquid react with vanillin, a flavor prohibited in tobacco cigarettes, to produce acetals. The effects of inhaling acetal chemicals are unknown, but the study notes that they can cause inflammation and lung irritation. The study found acetals in JUUL’s ‘Crème Brulée’ flavor. One researcher told Yale in an interview that the team was surprised to find such high vanillin chemical levels, pointing out that the detected levels reached those established for health limits on vanillin in bakeries and flavoring businesses.11
This study also found menthol in 4 of the 8 JUUL flavors it tested. Menthol, the researchers note, can expand nicotine intake. This could be concerning in part because JUUL pods already have high nicotine content relative to other nicotine products—individuals absorb from one JUUL pod as much nicotine as an entire pack of cigarettes. The researchers also observe that the findings are notable because users of the product often believe that the ingredients and chemical makeup of e-liquids are stable, without realizing that the included chemicals can combine, alter each other, or produce potentially harmful new compounds. The study calls for vaping regulations that tackle the creation of new and possibly toxic chemical elements in e-liquids, exposure to flavorings, and menthol levels.
Another new study, this time from the University of Pennsylvania, examined the effects of vaping on the vascular system and found that e-cigarette use, even without nicotine, can damage blood flow. Researchers studied 31 nonsmokers between the ages of 18 and 35, with no prior history of cardiovascular problems, hypertension, asthma, respiratory tract infections, or cancer. Participants in the study inhaled from e-cigarette devices 16 times each, at three seconds per inhalation. The researchers then used MRIs to measure the participants’ blood vessel health, having evaluated it before and after the vaping exercises. In the participants’ post-vaping leg veins, oxygen levels fell 20 percent, and their peak blood flow velocity fell 17 percent. Their femoral arteries also dilated 34 percent less. The researchers call for additional research on the topic to corroborate their findings in larger groups, and their results focus only on the ECO e-cigarette device, but they nonetheless point to serious concerns about chronic use of vaping products, which may not give time for users’ blood vessel health to normalize or reset.12
Why is this important?
Individuals who use vaping products can assume, on the basis consumer-focused “evidence,” that because e-cigarette makers claim that their products are a healthier alternative to tobacco products, they must be “healthy” overall. Some evidence does support the idea that vaping is preferable to smoking tobacco, which is why the United Kingdom’s government asserts that vaping is 95 percent less harmful than e-cigarette use and encourages e-cigarette users to switch to vaping.13 The dispute over this assertion may come down to the exact meaning of “less harmful,” but those with vaping-related lung disease would certainly argue that vaping is not safer than smoking tobacco. It’s also true that news reports on vaping can often overstate claims in the other direction, alleging or implying that e-cigarettes alone are responsible for severe lung distress. On this point, it may be useful to consider a similar research problem: attempting to determine whether smoking cannabis causes lung cancer when most cannabis smokers also smoke other drugs, and when many also smoke tobacco. By the time health officials and experts reach a definitive conclusion, it may be too late for those vaping. While exaggerations or misleading reports exist, they should not be used to support denial of mounting evidence, or instill confidence in vapers when new research shows obvious reasons to worry—and to worry about health more seriously than the “long-term effects are unknown” talking point.
The CDC’s overall position on vaping in recent years, subject to change, is that e-cigarettes “have the potential” to help adult smokers quit if they are not pregnant and can entirely substitute vaping for smoking tobacco products.14 Again, the CDC is now suggesting that individuals avoid vaping while investigations into the associated outbreak continue. It also says that scientists still have much to learn about e-cigarettes and warns that they are not safe for youth. The CDC, FDA, NIDA, and other authorities have recognized youth vaping as a growing epidemic, and have begun taking measures to confront it. Federal officials are now reportedly creating a plan to ban flavored e-cigarette products, which have a particular appeal to youth.15 Given the recent outbreak of severe lung problems and continued youth interest in e-cigarettes, additional action on this front will likely be required. Another recent study, for example, found 25 distinct “vape tricks” in 59 sample videos on YouTube with a median count of over 32,000 views.16 “Vape tricks” are stylized and playfully affected techniques for vaping, such as exhaling clouds in unique shapes, that attract the young. 48 percent of the videos were linked to industry posting accounts. This study recommended restrictions on e-cigarette social media marketing to help curb youth vaping, which sounds like a promising avenue for public health. Officials may also find it beneficial to take account of new studies about vaping’s effects on lung and blood vessel health as they deal with the increasingly apparent reality that e-cigarette use is not merely problematic in associated outbreaks, but in legal use, too.
Richtel, M., Grady, D. (September 6, 2019) Cases of Vaping-Related Lung Illness Surge, Health Officials Say. New York Times
Centers for Disease Control and Prevention. (2019) Outbreak of Lung Illnesses Associated with Using E-cigarette Products. Smoking & Tobacco Use, CDC.gov
Wrobleski, T. (September 8, 2019) Wait, you mean vaping isn’t safe after all? Silive.com
Christiani, D.C. (September 6, 2019) Vaping-Induced Lung Injury. The New England Journal of Medicine
Henry T.S.,, Kanne J.P., Kligerman S.J. (September 6, 2019) Imaging of Vaping-Associated Lung Disease. The New England Journal of Medicine, Epub ahead of print
Wipfli, H., Samet, J.M. (2016) One Hundred Years in the Making: The Global Tobacco Epidemic. Annual Review of Public Health
Edney, A., Turton, W. (August 29, 2019) Juul Devices Cited in Seizure Reports That Started FDA Probe. Bloomberg
Ghosh, A., Coakley, R.D., Ghio, A.J., Muhlebach, M.S., Esther, C.R. Jr., Alexis, N.E., Tarran, R. (August 7, 2019) Chronic E-Cigarette Use Increases Neutrophil Elastase and Matrix Metalloprotease Levels in the Lung. American Journal of Respiratory and Critical Care Medicine
Center for Tobacco Products. (2019) Warning Letter: JUUl Labs, Inc. fda.gov
Dackis, C.A., Gold, M.S. (1985) New concepts in cocaine addiction: The dopamine depletion hypothesis. Neuroscience & Biobehavioral Reviews
Weir, W. (July 30, 2019) Juul users inhaling chemicals not listed. Yale News
Avril, T. (August 22, 2019) Vaping without nicotine still harms blood vessels, Penn study finds. The Philadelphia Inquirer
Public Health England. (February 6, 2018) PHE publishes independent expert e-cigarettes evidence review. Gov.uk
CDC. (2018) About Electronic Cigarettes. CDC.gov
Kaplan, S. (September 11, 2019) Trump Administration Plans to Ban Flavored E-Cigarettes. New York Times
Kong, G., LaVallee, H., Rams, A., Ramamurthi, D., Krishnan-Sarin, S. Promotion of Vape Tricks on YouTube: Content Analysis. Journal of Medical Internet Research
1. Erythropel, H.C., Davis, L.M., de Winter, T.M., Jordt, S.E., Anastas, P.T., O’Malley, S.S., Krishnan-Sarin, S., Zimmerman, J.B. Flavorant-Solvent Reaction Products and Menthol in Juul E-Cigarettes and Aerosol. American Journal of Preventive Medicine
2. Caporale, A., Langham, M.C., Wensheng, G., Johncola, A., Chatterjee, S., Wehrli, F. Acute Effects of Electronic Cigarette Aerosol Inhalation on Vascular Function Detected at Quantitative MRI. Radiology
Dr. Mark S. Gold is a teacher of the year, translational researcher, author, mentor and inventor best known for his work on the brain systems underlying the effects of opiate drugs, cocaine and food. Read more by Dr. Gold here.