A customer exhales vapor from an electronic cigarette at the NXNW Vapor store in Sacramento, California, U.S., on Thursday, June 28, 2018. (Bloomberg)

The growing use of battery-powered e-cigarettes -- the activity known as vaping -- has provoked one of the most robust debates among public-health specialists in years. The debate has intensified as some users of vaping devices, which have been thought of as safer than lit cigarettes, have come down with mysterious and serious respiratory ailments.

1. What’s vaping?

It’s a way to ingest nicotine, the addictive alkaloid present in tobacco, without the smoke and tar that comes from burning tobacco. The vaping device contains a battery that heats a liquid spiked with nicotine, producing a vapor the user inhales. Vaping devices such as the popular Juul come in sleek designs and are small enough that an underage vaper, say, can palm it, discreetly take a hit when a teacher or parent isn’t looking, and breathe the resulting aerosol into a sleeve or collar. Vaping refills come in tasty flavors such as mango and creme.

2. Is it safer than smoking cigarettes?

That’s been one of its prime selling points -- that using e-cigarettes can help smokers wean themselves off traditional cigarettes and onto a habit less risky for their health. But now it appears that vaping is making more and more people sick. A mysterious lung disease that has been linked to inhaling vapor has killed six people and injured hundreds more people across the U.S. this summer. Doctors have seen hundreds of cases where patients -- often youthful, previously healthy adults -- have shown up in the emergency room, suddenly stricken with dangerous respiratory damage. State and federal investigators are racing to identity the precise cause of the ailment.

3. How popular is vaping?

Worldwide, the market for vaping products was estimated at about $11.5 billion in 2018 and is growing rapidly. Sales of the Juul in the U.S. rose more than 600% in a year to 16.2 million in 2017, according to the Centers for Disease Control and Prevention. Scott Gottlieb, former commissioner of the Food and Drug Administration, described teen vaping as an epidemic, even though kids younger than 18 aren’t legally allowed to purchase such products. According to a U.S. government survey, vaping among high-schoolers rose 78% from 2017 to 2018. That meant that about 21% of those students were indulging. Among middle-schoolers, the number who reported vaping rose 48%, to almost 5% of the group. These increases meant that overall use of tobacco products among young people increased 38%, reversing declines in recent years. Of about 80 countries that regulate e-cigarettes, 29 -- including Brazil, Greece, Saudi Arabia, Turkey and Thailand -- ban their sale altogether.

4. What are the concerns?

One is that, even if e-cigarettes help some adults quit more-harmful traditional cigarettes, they might be attracting hordes of new young people into a nicotine habit. Plus, as recent headlines can attest, there isn’t enough long-term data to make a definitive conclusion that vaping is a safer choice than lighting up. It’s plausible, although not proven, that e-cigarette aerosols can damage tissue and cause disease, including cancer. The effects on humans of nicotine are not well-studied, although adolescents appear to be particularly vulnerable to it, with some evidence suggesting it can harm brain development. A report by the U.S. National Academies of Sciences said there was substantial evidence that young vapers are more likely than nonvapers to try regular cigarettes.

5. What has the U.S. government done?

Declaring that the U.S. was experiencing an epidemic of teen vaping, the nation’s Food and Drug Administration in November 2018 announced plans to limit sales of most types of flavored e-cigarettes to vaping stores and online retailers who verify a purchaser is 18 or older. Now, on the direction of President Donald Trump, the FDA plans to issue regulatory guidance that will force the removal from the market of all vaping products that taste like anything other than tobacco. Sales could resume only with FDA approval. (Michael R. Bloomberg, the founder and majority owner of Bloomberg News parent Bloomberg LP, has campaigned and given money in support of a ban on flavored e-cigarettes and tobacco.)

6. What has the e-cigarette industry done?

Late last year, Juul said that it temporarily had stopped selling to stores its nicotine pods in flavors mango, fruit, creme and cucumber and was providing only tobacco, menthol and mint flavors. The measure was expected to cut Juul’s in-store retail sales by 45%, according to a person familiar with the company’s projections. Juul said it would continue to sell the fruity pods through its website, but the company said it was adding age-verification systems to ensure customers are at least 21. Tobacco giant Altria Group Inc. earlier announced that it was temporarily pulling its e-cigarettes MarkTen Elite and Apex by MarkTen from the market until the FDA gives the green light. (Altria bought a 35% stake in Juul last December.) Altria, Reynolds and Juul Labs have all said they would support legislation to raise the legal age for tobacco buyers to 21.

(An earlier version of this story incorrectly stated the minimum age Juul enforces for website sales.)

To contact the reporter on this story: Anna Edney in Washington at aedney@bloomberg.net

To contact the editors responsible for this story: Drew Armstrong at darmstrong17@bloomberg.net, Laurence Arnold, Timothy Annett

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