Understanding the Risks of Vaping

E-cigarettes have been linked to lung injury and other health issues. Here’s what we know about the risks involved.

woman using an e-cigarette

Updated on August 3, 2023.

A multi-state outbreak of a vaping-related lung illness first identified in August 2019 clearly challenged the dubious claim that using e-cigarettes is safer or healthier than smoking. 

As of February 18, 2020, 2,807 cases of “e-cigarette, or vaping, product use associated lung injury,” also known as EVALI, were confirmed in all 50 states as well as the District of Columbia, Puerto Rico, and U.S. Virgin Islands, according to the Centers for Disease Control and Prevention (CDC). Of these cases, 68 were fatal.

People who were sickened experienced serious symptoms, which developed over days or weeks, including:

  • Coughing
  • Shortness of breath
  • Chest pain
  • Nausea and vomiting
  • Abdominal pain and diarrhea
  • Fever and chills
  • Weight loss

The vaping illness was not limited to a specific age group. Those who died ranged in age from 17 to 75 years old, the CDC reported.

Though the outbreak raised as many questions about vaping than it answered, all patients who had been diagnosed, had one thing in common: They had recently vaped or used an e-cigarette product.

Certain ingredients may be to blame

On November 8, 2019, after testing fluid collected from the lungs of 29 people diagnosed with EVALI from 10 different states, health officials reported finding vitamin E acetate in all of the samples. This chemical is widely available as a nutritional supplement and isn’t known to be harmful when swallowed by mouth or applied to the skin. The health effects of inhaling vitamin E acetate, however, became a cause for concern because it’s an additive used in the production of vaping products.

Most of the people who were diagnosed with EVALI also reported using e-cigarette products that contained delta-9-tetrahydrocannabinol (THC), the primary mind-altering chemical in marijuana. In many cases, the THC vaping products linked to the lung condition were obtained informally from online or street dealers, friends, or family members.

This trend is particularly worrisome since the vaping of marijuana, which has increased dramatically in recent years, still appears to be on the rise, according to the annual Monitoring the Future Survey conducted for the National Institute on Drug Abuse (NIDA).

The December 2019 study of more than 38,000 middle and high school students revealed that 20.8 percent of 12th graders, 19.4 percent of 10th graders, and 7 perent of the 8th graders polled had vaped marijuana in the previous year. The survey, which was published in JAMA, also found that vaping marijuana was reported as a daily habit by 3.5 percent of the 12th graders and 3 percent of the 10th graders polled.

Recognizing the trend

There are hundreds of different e-cigarette brands being sold to consumers. You might hear a variety of different terms—like e-cigs, vapes, vape pens, mods, and hookah pens—but they’re all e-cigarettes. 

E-cigarettes come in different shapes and sizes. They may look like regular cigarettes, cigars, or pipes, but some look like pens or USB memory sticks and can even be charged on a laptop.

These products all operate in a similar way. Typically, a cartridge or reservoir of e-liquid or “e-juice” is heated by a battery-powered device, allowing users to breathe in the resulting vapor. It may be different from the smoke produced by traditional cigarettes but it’s important to understand that this vapor isn’t harmless.

Understanding the health risks

Like regular cigarettes, most e-cigarettes contain nicotine—an ingredient that can lead to addiction. Some e-cigarettes are free of nicotine, but they contain THC, while others have a mixture of both chemicals. Vaping THC oil, however, could be more harmful than smoking the drug, according to the NIDA. When vaping THC, users are often exposed to a higher concentration of the compound, which could increase their risk not only for addiction but also for negative health effects, explained NIDA director, Nora D. Volkow, MD, in a September 2019 teleconference.

The liquid in e-cigarettes may contain other potentially harmful chemicals, according to the American Lung Association, such as:

  • Formaldehyde
  • Glycerol and propylene glycol-based solutions
  • Acrolein
  • Volatile organic compounds
  • Metals, like nickel and lead

These chemicals could increase the risk for heart disease, lung damage, cancer and other serious health issues.

A December 2019 study examining the long-term health effects of vaping provided more compelling evidence that using e-cigarettes is linked to an increased risk for chronic lung diseases. For the study, researchers at UC San Francisco tracked the e-cigarette use and smoking habits of 32,000 people for a period of three years, from 2013 to 2016. The participants did not have lung disease when the research began.

The study, published in the American Journal of Preventive Medicine, found those who vaped were 30 percent more likely to develop asthma, bronchitis, emphysema, or chronic obstructive pulmonary disease (COPD) than those who didn’t vape. The researchers noted the risk for chronic lung disease more than tripled for those who vaped and also smoked cigarettes.

Although e-cigarettes have been touted as a tool to help smokers quit, a growing pile of research suggests this approach doesn’t work for many people who end up doing both—a behavior called “dual use,” according to Rose Marie Robertson, MD, the chief science and medical officer of the American Heart Association (AHA).

Meanwhile, one small study presented at the 2019 annual meeting of the AHA also suggested that vaping may have a greater effect on blood flow to the heart than smoking. Researchers compared the blood flow of a group of adults between 24 and 32 years old who vaped or smoked traditional cigarettes before and after exercise. In an otherwise healthy nonsmoker, blood flow would typically increase during exercise because the heart is working harder. Predictably, however, the blood flow of the cigarette smokers and vapers involved in the study decreased.

The researchers noted, however, that the blood flow of the traditional smokers improved during rest—but the same was not true for those who used e-cigarettes. These findings suggest that vaping could have lingering adverse effects on endothelial cells (the main type of cells found in the lining of blood vessels).

A small but striking study published in June 2019 in the Journal of the American College of Cardiology also found that use of flavored e-cigarettes, in particular, damages endothelial cells. Scientists suspect that such damage could lead to heart disease.

After exposing these cells to six different flavors of e-liquid in a lab, the researchers found the cells didn’t function normally. Certain flavors were more detrimental than others. The study’s authors noted that menthol tobacco-flavored e-liquid had a harmful effect, even if it was nicotine-free.

Many of the flavorings used in e-liquids are generally recognized as safe by the FDA for consumption by mouth, but there isn’t enough evidence to suggest they are safe to inhale.

Most manufacturers do not list the chemical compounds they use to create e-cigarette flavors, scientists at the University of Rochester Medical Center caution. In a December 2019 study published in Scientific Reports, the researchers detected nearly 40 different chemicals, including hydrocarbons and volatile organic compounds, in various combinations among seven vaping flavors made by one major manufacturer. The study showed these chemicals, which are known to be harmful if they are inhaled, may trigger oxidative stress, inflammation, epithelial cell dysfunction, and DNA damage in lung cells.

Complicating matters, e-cigarette flavorings—which include mint, menthol, strawberry, grape, chocolate, and even “Unicorn Cakes” and “Smurf Sauce”—appeal to young people and could make them appear less dangerous. This controversial marketing tactic prompted federal officials to initiate a ban on most flavored e-cigarette cartridges in January 2020. Some lawmakers say the ban doesn’t go far enough. Menthol and tobacco flavors are exempt from the new rule. It also allows flavored liquid nicotine, including flavors such as cotton candy and gummy bear, to be sold in open tank systems.

Long-term risks are unknown

The fact is, e-cigarettes haven’t been around that long. Researchers may not fully understand the dangerous health effects of vaping for another 50 years—which may be particularly ominous for adults who started vaping and became addicted to nicotine when they were in middle school.

Bottom line: If you don’t smoke or vape, don’t start. Children, teens, and pregnant women should never smoke, vape or use e-cigarette products.

For those who do vape, federal health officials advise against using any vaping or e-cigarette products that contain THC, particularly those obtained off the street. Since the exact cause of vaping-related lung illness isn’t yet known, however, the only way to ensure that you’re not at risk for the condition is to avoid all e-cigarette or vaping products, the CDC advises.

There is only limited evidence that e-cigarettes can help smokers quit. If you’re using e-cigarettes to try and stop smoking, talk to your healthcare provider (HCP) about smoking cessation strategies that are shown to be safe and effective. Your HCP can also work with you to develop strategies that would help you quit vaping.

And if you do choose to vape, be mindful about the warning signs and symptoms of EVALI, which may develop in the days and weeks after using e-cigarette products. Visit your HCP right away if you develop any symptoms of the condition.

Article sources open article sources

Centers for Disease Control and Prevention. “Outbreak of Lung Injury Associated with the Use of E-Cigarette, or Vaping, Products.”
Centers for Disease Control and Prevention. “Smoking & Tobacco Use. For the Public: What You Need to Know.”
NY State Department of Health. “New York State Department of Health Announces Update on Investigation into Vaping-Associated Pulmonary Illnesses.”
National Institute on Drug Abuse. “Marijuana.”
National Institute on Drug Abuse. “Electronic Cigarettes (E-cigarettes).”
American Cancer Society. “Questions and Answers About E-Cigarettes for Parents.”
Centers for Disease Control and Prevention. “Sales of JUUL e-cigarettes skyrocket, posing danger to youth.”
National Institute on Drug Abuse. “Cigarettes and Other Tobacco Products.”
American Lung Association. “E-Cigarettes.”
American Heart Association. “E-cigarettes take serious toll on heart health, not safer than traditional cigarettes.”
Won Hee Lee, Sang-Ging Ong, et al. “Modeling Cardiovascular Risks of E-Cigarettes With Human-Induced Pluripotent Stem Cell–Derived Endothelial Cells.” Journal of the American College of Cardiology. Volume 73, Issue 21, June 4, 2019.
U.S. Food and Drug Administration. “E-Liquids Misleadingly Labeled or Advertised as Food Products.”
U.S. Food and Drug Administration. “Trump Administration Combating Epidemic of Youth E-Cigarette Use with Plan to Clear Market of Unauthorized, Non-Tobacco-Flavored E-Cigarette Products.”
U.S. Food and Drug Administration. “Vaporizers, E-Cigarettes, and other Electronic Nicotine Delivery Systems (ENDS).”
Smokefree.gov. “What We Know About Electronic Cigarettes.”
T. Muthumalage, T. Lamb, M.R. Friedman, et al. “E-cigarette flavored pods induce inflammation, epithelial barrier dysfunction, and DNA damage in lung epithelial cells and monocytes.” Scientific Reports. 9, 19035 (2019).
Dharma N. Bhatta, PhD, MPH, Stanton A. Glantz, PhD. “Association of E-Cigarette Use With Respiratory Disease Among Adults: A Longitudinal Analysis.” American Journal of Preventive Medicine. Dec 2019.
Hongying Dai, PhD. “Self-reported Marijuana Use in Electronic Cigarettes Among US Youth, 2017 to 2018.” JAMA. December 17, 2019.
American Heart Association. The science about vaping dangers – and what we don’t know yet. December 2019.
U.S. Food and Drug Administration. “FDA finalizes enforcement policy on unauthorized flavored cartridge-based e-cigarettes that appeal to children, including fruit and mint.”
Dick Durbin: US Senate Illinois. “Durbin Statement On Trump Administration's New E-Cigarette Flavor Policy”

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