People in North and South America have been smoking tobacco for millennia. The reason is simple. Tobacco contains nicotine, a highly addictive stimulant. So smoking tobacco feels good and is difficult to quit. After being introduced to Europe, smoking became very popular, because it feels good and is difficult to quit. It wasn’t until the 1950s that the association between smoking and lung cancer was confirmed.

Electronic cigarettes (also called e-cigarettes, vape pens) in contrast, have been available in the US for a little over a decade. They are designed to deliver nicotine without combustion, thereby sparing the user all the harmful components in tobacco smoke. E-cigarettes contain an electronic heating element that heats and vaporizes a solution of nicotine. The vapor is then inhaled. (Using e-cigarettes is called vaping.) E-cigarette fluid (e-liquid) is also available with THC, the psychoactive compound in marijuana, rather than nicotine. E-liquids are also available with various flavor additives.

Since their introduction in the US market, e-cigarettes have become very popular, because nicotine feels good and is difficult to quit. (Have I mentioned that?) Proponents of e-cigarettes claim that e-cigarettes provide a safer alternative to smoking. They offer a way for current smokers to switch to a safer nicotine delivery system until they quit. Critics of e-cigarettes note that they have never been proven to be effective for smoking cessation, and their long-term safety is unknown. They also note that the flavors of e-liquids are clearly intended to make them palatable to teens, not to current smokers.

And that’s where the debate stood until a few weeks ago when a few users of e-cigarettes started getting very sick. Last week the Centers for Disease Control and Prevention (CDC) released an alert that 215 patients in 25 states have developed a severe acute illness involving cough, shortness of breath and chest pain. Some of the patients have required hospitalization. One patient in Illinois died. The patients were generally young and otherwise healthy, without a history of lung disease. The specific cause of these illnesses is still unknown. Tests for infectious organisms have been consistently negative and antibiotics have not been effective. Health officials suspect that a contaminant or solvent in the e-liquids is causing acute lung injury.

The CDC is asking doctors to help identify patients with these symptoms and submit their vaping equipment for analysis. The CDC suggests that members of the public who are concerned “consider refraining from using e-cigarette products”, and that those who do use e-cigarettes “should not buy these products off the street … and should not modify e-cigarette products or add any substances to these products that are not intended by the manufacturer.” (See the full Recommendations for the Public in the CDC alert.) Some state health officials are not being so reserved and are asking everyone who uses e-cigarettes to stop vaping until the cause of the illness is identified.

Eventually the contaminant causing these illnesses will be identified. Then it will either be eliminated, or for some secondary reason it will continue to be distributed in e-liquid. (Heroin mixed with fentanyl, for example, is a major reason for deaths due to opioid overdoses. But fentanyl persists as an intentional contaminant in heroin because of its potency. So if the contaminant in e-liquid adds a pleasant kick to nicotine or THC, maybe illicit distributors will continue using it.)

But these acute illnesses should bring attention to the question of long-term safety. We have no way of discovering the effects of thirty years of vaping until enough people have been vaping for thirty years. We had no way of figuring out that smoking caused lung cancer until lots and lots of smokers developed lung cancer.

Ask yourself if you’d like to be in the guinea pig cohort for vaping. If not, please get your nicotine from gums, patches or lozenges. You can reconsider vaping in 2050 or so.

Learn more:

Severe Pulmonary Disease Associated with Using E-Cigarette Products (Centers for Disease Control and Prevention)
The Mysterious Vaping Illness That’s ‘Becoming an Epidemic’ (New York Times)
As vaping-related lung illnesses spike, investigators eye contaminants (Washington Post)
First death in US from lung illness linked to vaping reported in Illinois (CNN Health)