When it comes to vaping, it can be hard to hear past the biased chatter from both sides to understand the actual drawbacks and potential benefits of this technology — just as it is with any growing trend where health and safety are concerned. Particularly with the rapid rise in popularity of vaporizers like the Juul among teens and young adults, questions and concerns about vaping have only become more pressing. To help you gain a more balanced understanding of vaping, we'll explore both the positive and negative aspects of the trend. We'll also look at the potential long-term health effects that are only beginning to be understood.
"Vaping" means inhaling vapor produced by an electronic cigarette or other vaporizer, devices which heat substances such as tobacco, cannabis, or their concentrated derivatives to extract their active ingredients far more efficiently — and, proponents argue, less harmfully — than the more traditional method of combustion, which produces smoke. In most cases, vaping refers to inhaling the vapor from flavored "e-juice" cartridges that contain various amounts of nicotine, which can be used to help some cigarette smokers quit.
Vaporizers are the wide variety of electronic devices used to turn liquid concentrates or dry herb into vapor. These include slender e-cigarettes made to resemble traditional cigarettes; larger vape pens — also known as APVs (Advanced Personal Vaporizers) — that often produce more vapor; and even bulkier, pricier vape mods that allow more customization. Newer designs include sleek-looking devices such as the Juul, which looks more like a USB-drive or pack of gum and is purposely made to look unlike a traditional cigarette.
Vaporizers have a rechargeable battery used to generate heat in an atomizer containing the vaping substance. This works via either a convection method, which uses air or gas to heat the substance, or a conduction method where the substance is heated directly, which may cause it to heat unevenly and burn, potentially worsening the effects on the user's lungs.
Users can vape dry cannabis or its waxy concentrated form, depending on the vaporizer. But vaping is most commonly associated with e-juice, which is sold in cartridges or bottles at dedicated vaping shops. It's made by many different companies in a multitude of flavors ranging from menthol to popcorn. Aside from nicotine and food flavorings (more on those soon), the chief ingredient in almost all e-juice is either propylene glycol or glycerol, which are used as bases to generate an aerosol resembling cigarette smoke when vaped. These have been found in some animal studies to contain little to no toxicity.
Nicotine is an addictive substance included in high, medium, or low concentrations in most e-juices. Even the high-concentration liquids deliver less nicotine than a conventional cigarette in the same time frame. And although vaporizers are often equated with cigarettes in American culture and policymaking, the two have little in common besides nicotine. Other carcinogenic contaminants in cigarettes may be present in tobacco-flavored vaping liquids, but at levels deemed too low to put vapers at risk.
Despite being one of the most studied drugs, nicotine was inseparable from tobacco for so long that its effects are little-understood. The general consensus is that nicotine itself poses limited risks, outside of developmental ones for young users and pregnant women. But its high potential for addiction has led some critics of vaping to claim it acts as a gateway to traditional cigarettes.
We don't know enough about vaping yet, but even with potential risk factors still coming to light, many consider it to be less harmful than smoking traditional cigarettes. One analysis from London's Royal College of Physicians estimated that the health hazards from e-cigarette use are unlikely to exceed 5 percent of the hazards inflicted by smoking tobacco.
There are roughly 7,000 constituents, or chemical components, that make up the contents of a single cigarette, and over 90 are known or potential carcinogens. The average e-liquid has very few constituents and, thus, far fewer carcinogens like tar. Even the harmful constituents of cigarettes that are in e-cigs, as well, are present in far smaller quantities.
Aldehydes are among the few harmful components of e-cigarettes that vapers must still worry about. When overheated, e-juice can release these harmful chemicals, such as formaldehyde, albeit at much lower levels than cigarettes, perhaps low enough to be negligible. Regardless, this results primarily from using a vaporizer not as intended, creating a harsher, drier puff that lets the user know something is off.
Cigarettes create two kinds of secondhand smoke — one kind exhaled by the smoker and the other, far more harmful kind released from the burning tip. Vaporizers create only secondhand vapor exhaled by the user, which is regarded as containing low concentrations of nicotine and other pollutants. To date, there is insufficient evidence to suggest that inhaling this vapor causes any measurable negative impact on bystanders.
Given that they are considered less harmful than ordinary cigarettes, e-cigs still have something of a PR problem in the U.S. A poll by Harvard's school of public health found that 32 percent of respondents deemed vaping as dangerous as traditional tobacco products, while 6 percent declared it more dangerous. This negative public perception may be why many states are now regulating public and indoor use of vaporizers like they do cigarettes.
E-cigarettes eliminate the stink of traditional cigarettes but can still cause some of the same short-term drawbacks associated with smoking. These potential side effects can include throat and mouth irritation, coughing, nausea, and vomiting, especially for new users or those vaping an atypically large quantity of e-juice in single sitting.
Although vaping may be easier on your lungs, recent findings suggest this method may not be much better than smoking for the user's mouth. One study showed that cells lining the mouth died at a much greater rate than normal following e-cig exposure, increasing the risk of gum disease, infection, and oral diseases such as xerostomia, or dry mouth, and stomatitis, an oral inflammation of ulcers.
Even when not in use, the separate components of e-cigarettes can pose a safety risk. There have been cases of vaporizers or their batteries overheating to the point of causing explosions, fires, and related bodily harm. Injuries and death have also resulted from young children coming into contact with nicotine-containing e-liquids, either ingesting it or having their skin exposed to a significant volume of it.
The immune responses to viral infection generated by one's nasal mucous membrane are known to be compromised in cigarette smokers, and the problem may be even worse for vapers. According to the American Association for the Advancement of Science, e-cigarettes with or without nicotine suppressed 305 more immune-related genes in users than cigarettes, which suppressed only 53.
Why would vaping cause more harm to the user's immune system than smoking? The most likely culprit seems to be the food flavorings of the e-liquid, a hypothesis supported by the AAAS study, which showed that the most suppressive effects to the subject's immune cells came from exposure to a single flavoring: cinnamon.
The FDA classifies flavoring agents used in e-juices as "generally recognized as safe" for oral consumption, but there's little research into their effects when inhaled. The flavoring diacetyl, used to mimic popcorn, has been known to cause respiratory issues (potentially by impairing immune function) since 2000, but in 2015 it was still found in as many as 39 out of 51 e-juice flavors available for consumption.
The FDA ruled last year that vape manufacturers and retailers must begin registering ingredients by August 2019, but until then, vapers will remain mostly in the dark about the potentially harmful flavoring agents present in any e-juice. Some vaporizing liquids have also been found to under- or overestimate the amount of nicotine present.
The current lack of regulations or labeling restrictions for vaping liquids means there's always a risk of unexpected contaminants, such as the poisonous diethylene glycol produced by nonpharmaceutical-grade propylene glycol. The FDA has warned e-cig manufacturers regarding cartridges contaminated with this and other additives like the weight-loss chemical rimonabant.
The American Heart Association reports that several toxicology studies have found that individual flavors of vaporizing liquid, like Ceylon cinnamon, are toxic to certain human cell cultures, including embryonic stem cells and fibroblasts, which are critical to wound-healing. This toxicity is correlated with flavoring levels in the liquids, lending support to the idea that the results of inhaling such flavoring agents are not yet sufficiently understood.
Despite the positive findings of animal studies on inhalation of the substance, the AHA notes that propylene glycol has been known to cause eye or respiratory irritation when used to generate theater fog. Thus, it's possible inhaling it from e-cigarettes on a regular basis may cause unknown respiratory harm, particularly for sufferers of asthma or other lung conditions.
Thermal degradation of the e-juice base from consistent heat can sometimes produce the derivative propylene oxide, a class 2B carcinogen, while degradation of glycerol can produce acrolein, an irritant tied to cardiovascular and pulmonary issues in cigarette smokers. Levels of these toxic byproducts, however, are many-fold lower in vaporizer emissions than cigarette emissions, although the levels increase when vaping at higher temperatures. The effects of exposure to low levels of both compounds are unknown.
Most of the cardiovascular effects attributed to vaping so far correspond neatly with the known effects of nicotine. Epidemiological studies have found no increased risk of stroke or myocardial infarction (also known as a heart attack) in vapers — only indications that e-cigarettes can contribute to acute cardiovascular events, especially for those already at risk from coronary heart disease.
There's been a great deal of concern that vaporizers will make smoking more attractive and accessible for non-users, opening the door to traditional cigarettes and other drugs, but the research is still decidedly split. A 2016 report by the World Health Organization lends credence to the idea, but it's hard to determine causation on the matter when those most likely to try e-cigs may also be likely to try traditional smoking regardless.
There are legitimate worries that this sleeker, smoother form of vaping will turn more young children and teens to smoking. The WHO report shows a rapid increase in vape-use among non-smoking youth in the U.S., particularly Florida, and a CDC survey found that while only 32 percent of high schoolers reported trying cigarettes, 45 percent admitted to trying vape products.
Again, the research is split. In the U.K., e-cigs containing nicotine have been found to help a smoker's chances of quitting and/or their lowering intake, while a U.S. study found that e-cigarettes actually lowered the chances of quitting by 28 percent. Whether the contradictory findings result from cultural differences or simply random variations between test-subjects, it's impossible to say for sure.
Vaporizers have been available for only a little over a decade, so we still don't know the extent to which vaporizers and e-cigarettes may affect the health of long-term users. While scientific understanding of vaping continues to advance on an almost-daily basis, it still may be several decades before its effects are fully understood.