Up in Vapor

Up in Vapor

As more people embrace e-cigarettes, scientists weigh in on whether
“healthier” is actually healthy
By Cheryl Alkon

E-cigarettes are hot, both literally and figuratively.

When the American Journal of Physiology—Lung Cellular and Molecular Physiology put out a special call for papers in 2017 through 2019 about the science and research of electronic cigarettes and vaping titled “Electronic cigarettes: not all good news?” the response was overwhelming.

“We received more correspondence related to our call for e-cigarettes than we have for anything else,” says Rory E. Morty, PhD, the journal’s editor-in-chief and research director at the European Respiratory Society. “People tend to have strong opinions about the subject, positive or negative.” Dr. Morty is also a research scientist in the Department of Lung Development and Remodeling at the Max Planck Institute for Heart and Lung Research in Bad Nauheim, Germany, and a physician at the Department of Internal Medicine (Pulmonology) at the University of Giessen School of Medicine and the teaching hospital of the University Hospital Giessen and Marburg, Germany.

The question mark in the call for papers’ title was meant to reflect both the benefits and drawbacks of electronic cigarettes, a system where users inhale, or “vape,” a heated vapor into their lungs. The vapor typically includes nicotine, propylene glycol and glycerin, as well as assorted flavorings such as fruit, candy or chocolate; it has been found to contain volatile organic compounds and heavy metals as well. E-cigarettes are marketed as a cleaner, healthier alternative to traditional cigarettes, but researchers counter that “healthier” is not the same as having “minimal” or “no” health risks.

Researchers submitted about 30 papers in response to the call; the journal has since published 14 papers on various aspects of e-cigarettes and vaping. Each paper, Dr. Morty says, "robustly reported on experiments that suggest that e-cigarettes may be less damaging than combustible cigarettes, as well as studies highlighting concerns about the safety of e-cigarettes and their damaging effects on the lungs."

As the debate continues, the journal aims to provide a neutral platform where physiologists can exchange data and interpretations about the topic, Dr. Morty says.

WHAT THE RESEARCH SAYS

Electronic cigarettes have been around in the U.S. since 2007, according to Laura E. Crotty Alexander, MD, associate professor of medicine at the University of California at San Diego and staff physician at the VA San Diego Healthcare System. For the past six years, her lab has studied whichever product is most popular at the time. At first, she researched vape pens, then moved to devices known as mods. Now she focuses on Juul, a brand of e-cigarette that resembles a USB flash drive and currently dominates the market. Fifty percent of all American e-cigarette users choose Juul.

Since these products have only been available little more than a decade, “it will take a really long time to know exactly what they are doing,” Dr. Alexander says. “E-cigarettes will cause health problems and diseases, and we are working as quickly as possible to identify the causal factors.”

Dr. Alexander works with mouse models as well as human subjects and says that early cell-based and animal studies indicate the e-cigarette vapor has adverse effects on cells, tissues and organs. “It’s unclear how many years it will take for people to develop cardiovascular, kidney and brain effects. But we see that e-cigarette use is altering the lungs under certain conditions.”

Dr. Alexander looks at how mice respond in experiments lasting three to six months (the equivalent of three to six decades in humans) and then looks for early signs of the same problems in her human subjects, typically through changes noticed in human blood tests.

“What that will look like is increased airway activity, and asthma and bronchitis will be revved up with airway bronchoconstriction,” she says. “The immune system is being dramatically altered by exposure to e-cigarette vapor as well. Many immune cells don’t work correctly, and I’m worried people will be at risk for more infections and more severe infections. Finally, it looks like e-cigarettes are driving inflammation, indicating that allergies will go up, and we’re seeing signals that some of the rheumatological diseases might get worse.” Other potential problems could be the development of acute interstitial pneumonia, eosinophilic pneumonia and lipoid pneumonia, based on how different immune cells react to e-cigarette use.

Dr. Alexander and others’ papers have shown that e-cigarette vapor induces double-stranded DNA breaks, which is associated with the development of cancer, but the vapor caused fewer strand breaks than traditional cigarette smoke. This means e-cigarettes might have a lower cancer risk compared to regular cigarettes, but the cancer risk remains unknown.

Using Juul products, called Juuling, is particularly concerning, as it is causing a nicotine addiction epidemic among young adults who would have otherwise not starting smoking, says Ilona Jaspers, PhD, University of North Carolina at Chapel Hill professor in pediatrics, microbiology and immunology, and environmental science and engineering. Dr. Jaspers is also the director of curriculum in toxicology and environmental medicine and deputy director of the Center for Environmental Medicine, Asthma and Lung Biology.

Juul itself delivers a higher amount of nicotine to the lungs than a traditional cigarette does, and “the teen brain gets addicted to nicotine faster than someone in their 40s or 50s does,” Dr. Jaspers says. A 2016 University of Michigan study showed that the majority of teenagers thought they were only vaping flavoring, not nicotine, with an e-cigarette. Combined with targeted advertising to teens and young adults that makes Juul seem hip, along with social media posts that glamorize Juul accessories, plus some classic peer pressure, Juul addiction is “a perfect storm,” Dr. Jaspers says.

In the U.S., one Juul cartridge contains 20 cigarettes’ worth of nicotine, which is equivalent to the nicotine in a pack of traditional cigarettes, according to the Truth Initiative, an anti-tobacco campaign. If a person vapes one pod a day, that’s like smoking one pack of cigarettes, as far as the nicotine intake.

With mod devices, users took in 3–6 mg/ml of nicotine at a time, but Juul users inhale 59 mg/ml at a time—a significant increase, according to Dr. Alexander.

DOES “HEALTHIER” = HEALTHY?

While vaping is sold as a healthier, greener alternative to combustible cigarettes and are touted for their lack of ash or tobacco smell, positioning e-cigarettes this way is harmful, Dr. Jaspers says.

“Traditional cigarettes are the No. 1 cause of preventable deaths, have been linked to numerous different cancers and other chronic diseases and contain almost 70 cancer-causing chemicals,” she says. “It would be difficult to imagine a consumer product that is worse for your health than cigarettes.”

Comparing the two types of cigarettes and asking if e-cigarettes are healthier is a loaded question, Dr. Morty says. While e-cigarettes don’t have many of the toxic substances such as tar and smoke that exist with traditional cigarettes, e-cigarettes “may contain more nicotine, which is not healthy, and they generate steam, which may also irritate the lung,” he says. Vaping solutions also contain formaldehyde, and the e-cigarette device itself generates nanoparticles—neither of which are healthy to inhale.

There are also reports of the devices exploding in the hands and mouth of users, causing physical damage and medical emergencies, as well as the potential for burn hazards. “These physical concerns are not theoretical since case reports are appearing regularly in the medical literature that highlight this spectrum of dangers to e-cigarette users’ health,” Dr. Morty says.

E-cigarettes and vaping are making it easier for people to become addicted to nicotine than they would have if they had started smoking cigarettes. With public health efforts, fewer people are starting smoking such cigarettes because “in comparison, smoking a cigarette seems gross,” Dr. Alexander says.

None of the researchers interviewed for this story have tried e-cigarettes. But people who have vaped with Juul tell Dr. Alexander that “it’s like chugging a whole beer. It’s such a high that the addiction potential is so much worse,” she says. “You don’t have to use them much, but nothing else with give you the same level of activation of the dopamine reward pathway. That’s why the addiction potential is so intense.”

Another problem is that there is a lack of clinical data on pharmacological efficacy of smoking-cessation medication in younger people, Dr. Jaspers says. Smoking cessation therapy typically consists of a combination of group therapy, reinforcement and other psychological aspects, which either have not been widely studied or are not recommended for people younger than 18.

“There is a problem and a lack of awareness,” Dr. Jaspers says. Pediatricians don’t know how to help their young patients, she added, while “adult pulmonologists, on the other hand, tell their adult smokers to try e-cigarettes. The messaging is confusing, and that is part of the problem.”

CESSATION ADVOCATES AMONG E-CIGARETTE SKEPTICS

U.S.-based smoking cessation experts are fairly consistent with their disapproval of e-cigarettes, grouping them with all tobacco products in policy and practice. Many cities and states have followed suit and ban vaping in public places such as airports and restaurants, Dr. Alexander says.

The Truth Initiative “has done a really good job in providing information directly targeting teenagers and young adults, and I like the fact that they clearly state that ‘safer than smoking doesn’t make it safe,’” Dr. Jaspers says. However, such advertising needs to be sought out to be found. “You have to go to their website to see it, and even though there are television commercials, how many kids are watching them on live TV? We just got rid of cable in our own house because no one was watching it.”

The mixed messaging continues to make the issue less clear cut. “E-cigarettes come with their own set of health concerns, but it is also fair to point out that in the limited number of studies conducted to date, e-cigarettes are twice more successful as, for example, nicotine patches, in promoting smoking cessation,” Dr. Morty says. “At the same time, there are real concerns about e-cigarettes being a means for adolescents to smart smoking, and perhaps, also promoting progression from vaping to smoking combustible cigarettes. These are probably the biggest public health concerns related to teen smoking.”