An employee demonstrates vaping at an e-cigarette store. U.S. health officials have called underage vaping “an epidemic.” (Arnd Wiegmann/Reuters)

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The promise of electronic cigarettes is straightforward: Lifelong smokers can wean themselves off a toxic habit in favor of an alternative that isn’t packed with tobacco and dozens of unsafe carcinogens.

But e-cigarettes and vaping products present health concerns of their own, experts say, and that’s due in part to nicotine.

That was a point underscored last week when the Food and Drug Administration proposed a policy designed to restrict how and where flavored e-cigarettes are sold — an effort to combat what the agency’s commissioner has called “an epidemic” of underage vaping. The initiative would limit sales of fruity and kid-friendly vaping products to stores that bar minors or have separate adult-only sections.

In a sharply worded advisory issued in December, U.S. Surgeon General Jerome M. Adams implored parents, teachers and health professionals to take steps to rein in e-cigarette use.

E-cig use among teens has soared in the past year. More than 3.6 million youths — about 1 in 5 high school students and 1 in 20 middle school students — reported using e-cigarettes, Adams noted in the advisory. A survey from the National Institute on Drug Abuse, released the same week, noted that more than one-third — or 37 percent — of high school seniors had vaped at least once in the past year, up 10 percent from a year prior.

Adams singled out e-cigarette manufacturer Juul Labs as part of the reason for the soaring use, saying one of its cartridges contains about as much nicotine as a pack of 20 regular cigarettes. His advisory pointed out that approximately two-thirds of Juul users ages 15 to 24 aren’t even aware that the devices always contain nicotine.

(Juul responded by saying its goal is in fact to prevent youth “from initiating on nicotine” and said that it had taken steps to prevent young people from using its products. The company stopped selling most of its flavored pods at retailers and also beefed-up age-verification for its online sales.)

For young people, that nicotine content is particularly troubling, according to health experts who spoke with CR.

“The number one concern is the addiction power of the nicotine,” says Ana Navas-Acien, professor of environmental health sciences at Columbia University’s Mailman School of Public Health. “We know that nicotine is an incredibly addictive substance, and we also know the younger you are when you’re exposed to that chemical, the more likely it is that you will be highly addicted to it.”

Research on the effects of nicotine addiction stemming from e-cig use is still in its infancy, Navas-Acien says. But it’s better to start examining the effects now than later.

“The question is, how long do you wait until you know everything before taking action?” she says. “I think it’s important from a public health perspective to really — given the potential for toxicity, given the extremely addictive power of this product — think carefully before the epidemic is out of proportions.”

Nicotine and the brain

The addictive quality is key. Young people are “significantly more likely” to become addicted to nicotine than adults, says Bonnie Halpern-Felsher, a developmental psychologist and professor of pediatrics at Stanford University, as their brains are continually developing up until about age 25.

“During that time, anything we introduce into it actually changes our brains,” Halpern-Felsher says. “So, by introducing nicotine, an addictive substance for which we already have receptors in place, we heighten those receptors and the brain alters to want more nicotine after.”

While nicotine itself is known to increase blood pressure and has been linked to heart disease, its biggest risk, experts say, is its addictive qualities. That’s because the more addicted you are to nicotine, the more often you will likely use the devices, increasing your exposure to other harmful compounds, Navas-Acien says. For example, a study published last year in the journal Pediatrics found that e-cig devices contain some of the same cancer-causing ingredients found in traditional cigarettes.

E-cigs and regular cigarettes

Another area of interest among researchers is whether addiction among e-cig users prompts them to move on to regular cigarettes, says Micah Berman, associate professor of public health and law at Ohio State University.

“It seems to be that nicotine exposure in kids is linked to development in mood disorders, attention disorders, other drug-seeking behaviors,” Berman says.

A study published in October 2018 by the Rand Corp. surveyed more than 2,000 people in California, ages 16 to 20, over a three-year period, and found that the longer they used e-cigs, the more likely they were to also start smoking regular cigarettes. At age 17, more teens (8 percent) reported using e-cigs than regular cigarettes (6 percent) in the past month. But by age 19, those numbers reversed, with 12 percent of them now saying they smoked cigarettes compared with just 9 percent of those saying that they used e-cigs.

Nicotine and the heart

While researchers have long known that nicotine in cigarettes can raise blood pressure, only recently have they shown that it can have the same effect when it’s in e-cigarettes, too.

In 2016, researchers in Sweden recruited 15 volunteers who were seldom smokers, and had them use e-cigs with nicotine for 30 minutes on one day, followed by an e-cig without nicotine for 30 minutes the other day.

They found a “significant” increase in blood pressure in the first 30 minutes after the nicotine-packed e-cig was smoked, while there was no similar effect for the nicotine-free device, according to the European Lung Foundation, which detailed the study in 2017.

Magnus Lundbäck, a researcher at the Danderyd University Hospital, Karolinska Institute in Sweden, described the findings in a statement at the time as “preliminary,” but he said that the rise in blood pressure “is most likely attributed to nicotine.”

 Copyright 2018, Consumer Reports Inc.

Consumer Reports updated this article to include the age ranges of the Juul users in the survey highlighted by the U.S. surgeon general, as well as the fact that the survey asked whether Juul users knew that the devices always contain nicotine.

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