Vaping has become a fad too big to ignore. By one estimate, some 35 million people vape. Roughly 14 million of those individuals live in the US, and over 3 million are middle or high school students. US teens are even vaping more than they’re having sex.
Since they came on the market, e-cigarettes have been positioned as an alternative to cigarettes. No doctor recommends vaping on its own, but some consider it part of the arsenal to help quit smoking. Some studies have shown that vaping e-cigarettes is actually better (paywall) at getting people to quit than nicotine patches or gum.
But in the last few months, reports of serious health consequences have brought vaping’s safety into question. In April of this year, the US Food and Drug Administration (FDA) began looking at the links between vaping and seizures after at least 35 reports surfaced. That same month, doctors reported the first case of a sudden-onset, severe lung illness associated with vaping. By August, similar cases had popped up across the country. Later that month, the first person died of this mysterious condition in Illinois.
The cases now number more than 450, with at least five deaths reported as of last Friday (Sept. 6). The illnesses have led the US Centers for Disease Control and Prevention to issue a rare warning about vape products, telling the public to “[refrain] from using e-cigarette products” if they have concerns about specific health risks. A group of physicians recently published an opinion in the New England Journal of Medicine stating “efforts should be made to increase public awareness of the harmful effect of vaping, and physicians should discourage their patients from vaping.”
Here’s what we know—and what’s still unclear—about the health concerns tied to vaping so far:
So what is vaping, actually?
Vaping is actually a misnomer.
Vapes deliver nicotine or cannabis without the smoke characteristic of cigarettes, but not as vapor, or gas: A puff contains aerosolized particles of liquid suspended in air. In addition to the nicotine found in e-cigarettes, or cannabis products found in other vapes, the liquid cocktail in vape cartridges may contain a whole host of chemicals designed to flavor or emulsify the fun components. The medical community has largely been wary of vapes because they’re a new kind of chemical exposure.
Juul is the leading vape manufacturer, and its products have to be used in a Juul-specific device. But there are hundreds of brands that sell both cannabis and nicotine cartridges that can be smoked in hundreds of devices. It’s fairly common, though not recommended, for users or resellers to alter e-cigarette cartridges to have either higher nicotine concentrations or to add THC to them.
How is vaping tied to the severe, sudden-onset lung illness we’re hearing about?
In each reported case of severe respiratory distress, patients reported vaping heavily. The New York Times reports that most of these patients were young men with a median age of 19, although some have been as old as 65. Patients had been vaping cannabis products in most cases, but some had been smoking altered e-cigarettes with high nicotine contents. They arrived at the hospital with a combination of symptoms reflecting lung destress: trouble breathing, chest pain, fatigue, and nausea and vomiting in some cases.
Scans have shown that their chests look similar to those with pneumonia. Patients’ lungs seem to be launching a massive immune response, except their white blood cells are filled with fats instead of an infectious agent. Health care providers can treat the inflammation with steroids and ventilators to assist patients’ breathing.
Are unknown chemicals causing the severe lung illness?
It’s not clear, in part because there are too many of them to reliably track.
The safety of many of the chemicals in vape cartridges is often unknown. Legitimate manufacturers have to register their products with the FDA, including a detailed ingredient list, and most of the chemicals are “generally regarded as safe” for ingestion, including the main carriers propylene glycol and glycerol. There’s less information, though, on how these chemicals affect the lungs as compared to the skin or digestive tract.
Plus, the amount of certain chemicals in vape products may be much higher than previously recorded safe amounts. One analysis from researchers at the University of California, Riverside, found a cinnamon flavoring present in some vape cartridges at 36 times the “safe” amount.
Illegitimate cartridges may also contain more harmful chemicals—particularly if they contain cannabis products, which aren’t regulated by the FDA because of marijuana’s standing as a schedule 1 drug. It may be hard to tell if a particular product is from a legitimate retailer or not. Last month, for example, Inverse reported that one company, called Dank Vapes, was posing as a manufacturer, but was actually a marketing company that provided product labels to black market THC vapes—some of which were found to include dangerous levels of chemicals used as fungicides. Dank Vapes has been implicated in some of the lung illness cases.
These unregulated cartridges have always been cause for concern. Part of the CDC’s official warning states that “regardless of the ongoing investigation, anyone who uses e-cigarette products should not buy these products off the street (e.g., e-cigarette products with THC, other cannabinoids) and should not modify e-cigarette products or add any substances to these products that are not intended by the manufacturer.”
The Washington Post reported that one substance the FDA found in some of the vapes used by hospitalized patients was vitamin E acetate—an oil lungs aren’t well-equipped to handle. However, this chemical wasn’t present in all the vape cartridges tested, which included both cannabis and regular e-cigarettes, meaning there could be other chemicals to blame. There are also concerns that a vape’s heating coils themselves, which are made of metal, can release particulates into the lungs.
Realistically, though, there could be multiple harmful substances in vapes, or combinations of them that cause dangerous interactions. Public health professionals don’t yet have enough data to implicate one compound over another.
What about the long-term effects of vaping?
That’s the million-dollar question that’s puzzling epidemiologists.
Vaping has only been around in the US since 2007; that’s not enough time for public health professionals to reliably track the long-term effects of vaping.
Besides, tracking such an issue would be incredibly difficult, given the variety of ways that people smoke, and the fact that many vapers are simultaneously using cigarettes and alcohol, Michael Blaha, cardiologist and clinical researcher at Johns Hopkins University, told Quartz.
Scientists are in the early stages of studies that track long-term users, but it’ll be years before we see those results. As the CDC has warned, the safest course of action to take, if you have concerns, is to stop vaping.
In the meantime, if you are going to continue to vape, it’s best to stick with products you trust come from legitimate manufacturers.
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