[Originally published: September 13, 2018. Updated: September 7, 2019.]
During a recent media briefing, the Centers for Disease Control and Prevention (CDC) advised people to avoid e-cigarettes while federal and state officials investigate a nationwide outbreak of severe respiratory illnesses associated with the use of e-cigarette, or vaping, products.
“Of course, e-cigarette use is never safe for youth, young adults, or pregnant women,” said CDC’s Dana Meaney-Delman, MD, who is managing the agency’s response to the outbreak.
Federal and state officials have reported hundreds of total possible cases of pulmonary disease and several deaths that may be related to vaping. Patients’ symptoms ranged from cough, chest pain and shortness of breath to fatigue, vomiting, diarrhea, and fever, according to the CDC.
“Based on clinical and laboratory evidence to date, we believe that a chemical exposure is likely associated with these illnesses,” Dr. Meaney-Delman said. “However, and I really want to stress this, more information is needed to determine which specific products or substances are involved.”
As part of their investigations, state health officials have sent samples of products to the Food and Drug Administration (FDA) for analysis. The FDA is evaluating these samples for THC (the high-inducing compound in marijuana), nicotine, Vitamin E acetate, and a range of other chemicals.
Even if or when a potential culprit is identified, Mitch Zeller, director of FDA’s Center for Tobacco Products, cautioned that it will be only “one piece of the puzzle…and it makes all of our ongoing work that much more critical.”
Last year, the U.S. Surgeon General’s office began the work of awareness when the nation’s doctor, Jerome Adams, MD, issued a warning that vaping among youth has reached epidemic levels.
The numbers are startling. More than 3.6 million middle and high school students currently use e-cigarettes, according to the latest National Youth Tobacco Study. Another national study last year found that 11 percent of high school seniors, 8 percent of 10th-graders, and 3.5 percent of eighth-graders vaped with nicotine during a previous one month period. The worrying part? Young people think vaping is mostly harmless.
To understand vaping, it’s best to start on broad terms. To vape is to inhale vapor created from a liquid heated up inside a device. From there, things quickly get complicated. The devices have many names—vape pens, pod mods, tanks, electronic nicotine delivery devices (ENDS), e-hookahs and e-cigarettes. The liquid they contain also has many monikers—it might be called e-juice, e-liquid, cartridges, pods, or oil. Most vape liquids contain a combination of propylene glycol or glycerol—also called glycerin—as a base, and nicotine, marijuana, or flavoring chemicals to produce common or outlandish flavors, from mint to “unicorn puke.” The devices rely on batteries to power heating elements made of various materials that aerosolize the liquid.
What’s more, the San Francisco-based company that sells Juuls—currently the most popular vaping device on the market—offers vape liquid made from nicotine salts found in loose-leaf tobacco instead of the traditional free-base nicotine found in most e-cigarette liquid. This may allow the user to experience a higher—and more addictive—concentration of nicotine, according to an article in The New England Journal of Medicine.
Since e-cigarettes arrived in the U.S. in 2007, they have been investigated by addiction researchers as possible cessation devices for adults trying to quit combustible, or regular, cigarettes. The Food and Drug Administration (FDA) lists 93 harmful or potentially harmful chemicals found in regular cigarettes, and the National Cancer Institute (NCI) describes cigarettes as having more than 7,000 chemicals in them. E-cigarettes contain fewer chemicals and so the industry has presented them as a healthier alternative to regular cigarettes. But vape liquids can still contain nicotine, a highly addictive drug.
And on one point, Yale health researchers who study the health effects of vaping and e-cigarettes agree: Vape devices have not been proven to help adult smokers quit smoking. Moreover, vaping increases the risk a teen will smoke regular cigarettes later.
“The addiction to nicotine and later conversion to (or dual use with) regular cigarettes are the greatest concerns,” says Roy S. Herbst, MD, Yale Medicine’s chief of medical oncology at Yale Cancer Center. He points to two heavyweight organizations, the American Society of Clinical Oncology (ASCO) and the American Association for Cancer Research (AACR), that have issued statements that vaping could be harmful to youth. (Dr. Herbst chairs the AACR Tobacco & Cancer Subcommittee that led the development of the statement.)
The popularity of Juul is worrying to addiction researchers. Juuls arrived late to the e-cigarette market in 2015, about eight years after vaping devices first began appearing in the United States. But the company, called Juul Labs, has surged ahead of competitors. Juul accounted for 72 percent of the e-cigarette market in August 2018, according to news reports. Sleek and slim, with an appearance that mirrors a flash drive, Juul has been established among youth as the vaping tool of choice. Teens even morphed the brand into a verb—juuling—according widespread news coverage chronicling its rise. “When we ask teens about their vaping or e-cig habits, they don’t even consider juuling to be part of that,” says Suchitra Krishnan-Sarin, PhD, co-leader of the Yale Tobacco Center for Regulatory Science, one of nine centers in the country currently funded by the National Institutes of Health (NIH) and the FDA to foster tobacco regulatory research.
Juul and other vape manufacturers, including Vuse, MarkTen XL, blu, and Logic, came under scrutiny by the FDA for marketing and sales practices that seemed aimed at teens and young adults, according to an announcement the FDA released in September 2018. At the time, the agency asked the companies to submit plans on how they planned to address widespread youth access and use of their products.
“We cannot allow a whole new generation to become addicted to nicotine,” former FDA Commissioner Scott Gottlieb, MD, said in the release.
Surgeon General Adams shared similar concerns, which he outlined in a news conference last year: “The number one reason young people say they try these devices is because they have flavors in them,” Dr. Adams said, noting that e-cigarettes come in kid-friendly flavors.
While it’s possible to buy liquid without nicotine for some e-cigarettes, it’s not possible to do so with popular pod mod devices. According to Juul’s website—in a description that has since been taken down—a single Juulpod contains 40 mg of nicotine, which is similar to “the nicotine yield of a pack of cigarettes.” (The company also sells Juulpods with approximately 23 mg of nicotine.) But researchers explain that it’s difficult to describe a single pod as a “serving.” A person might consume one pod in a week, while another may take only one day.
A stubborn trend
When potentially risky behaviors experience an uptick in popularity, health researchers are never far behind—gathering data. A Yale study last year found that, among students at three Connecticut public schools, those who used e-cigarettes were more likely to smoke regular cigarettes in the future.
Krishnan-Sarin points to progress that has been made—finally—in recent years to reduce regular cigarette smoking rates among young adults. In her opinion, the significant decline is due to the success of large-scale public health campaigns and a general awareness among youth that cigarettes are harmful to health.
She is concerned that most teens who vape with nicotine don’t know the drug can be damaging to their development. “We have a lot of evidence showing that the adolescent brain is extremely sensitive to the effects of nicotine,” she says, adding that the brain doesn’t stop growing until around age 25. “Studies have shown us that nicotine can interfere with memory and attention processing.”
In his imaging studies of adults who use e-cigarettes, Stephen Baldassarri, MD, an internist at Yale Medicine, has begun to gather information on the factors that influence nicotine delivery from e-cigarettes and whether vaping promotes cessation from conventional cigarette smoking. Teens cannot participate in such studies, but “we all agree that e-cigs are not a good thing for youth and nonsmokers,” Dr. Baldassarri says.
How to talk to your kids
Probably the worst thing a parent could do for their child would be to buy an e-cigarette under the misconception that this might prevent them from smoking regular cigarettes, Krishnan-Sarin says. She encourages parents to talk openly and freely about vaping—with the caveat that they provide accurate information. “I think the problem is that parents lose credibility if they say something to try and convince their child, who then finds out that it isn’t true,” she says.
"Parents should base their information on accurate facts and also encourage their children to read about and understand the science on this issue instead of relying on what their friends and peers tell them."
Dr. Baldassarri suggests explaining the addictive nature of vaping, which would mess with the one thing teens crave the most: independence. “In some ways, when you get addicted to a drug, it’s like losing your freedom of choice,” he says. “The risk of losing that freedom might be a persuasive message for kids.”
Deepa Camenga, MD, a pediatrician who is board-certified in addiction medicine, says it’s never too early to begin talking about e-cigarettes in age-appropriate language. “When you are out and about with your children and see an advertisement, for example, take the opportunity to talk about it,” she says. As they grow older, parents can expand on their thoughts and expectations. “It’s also important to give teens and young adults the space to ask questions,” she says.
Patrick O’Connor, MD, Yale Medicine’s chief of general internal medicine, who has dedicated his career to researching opioid and alcohol drug abuse, points to similarities between epidemic cigarette use in the 1940s and 50s, and e-cigarette use now.
Even as evidence accumulated on the link between lung cancer and cigarette use, doctors didn’t always take time to talk to patients about those risks, he says. “I think it’s a major responsibility of physicians, family medicine doctors, pediatricians, and adolescent medicine practitioners. One of the big deficits in medical education has been to prepare medical students to address these issues with their patients, ask them about their use of these substances, and advise them on the risks,” Dr. O’Connor says. “This is as true for e-cigarette use and vaping as it is for alcohol and other drug use.”
What may be the most important message of all is that e-cigarettes and vaping come with many health unknowns, Dr. O’Connor adds. “You see plumes of what looks like steam coming out of people’s mouths on the street when they are vaping, and I think they assume it’s mostly safe, mostly water. But these liquids used in vaping are filled with all kinds of stuff [like nicotine, marijuana, flavoring agents, chemicals], and we don’t always know what else is in there,” he says.
Surgeon General Adams echoed these concerns in his news conference following the release of his advisory: “Studies show that youth, like my son, have no clue what's in these products most of the time.”
Months after the release of the advisory, Yale researchers found that byproducts, called acetals, form when flavoring agents mix with solvents in the liquid. It is not yet known if this has negative effects on the body, but Sven-Eric Jordt, PhD, one of the study’s authors, says he hopes that the FDA will begin to study the short- and long-term effects of inhaled acetals. “We want these companies to be more transparent about what’s in their liquids,” he says.