02:08 - Source: CNN
So what's in those e-cigarettes?

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NEW: E-cigarette use is epidemic among teens, says FDA

NEW: FDA cracking down on sale of e-cigs to minors

CNN —  

E-cigarettes are increasingly being used as a nicotine alternative as smokers seek ways to kick their habit. They work by heating a pure liquid called e-juice – composed of flavorings, propylene glycol, glycerin and often nicotine – until it vaporizes. The resulting vapor is much less offensive to both smokers and non-smokers.

But their use has become controversial due to a lack of evidence on their efficacy as anti-smoking aids, warnings about possible long-term health effects and numerous studies showing that teen use is a direct gateway to traditional cigarette smoking.

The latest salvo: Concerned with an “epidemic” surge in e-cigarette use by adolescents, the Food and Drug Administration took regulatory action against more than 1,300 US retailers and five major manufacturers for their roles in perpetuating youth access to e-cigarettes.

Calling it “the largest coordinated enforcement effort in the agency’s history,” the FDA told Juul and four other major manufacturers to provide plans to control sales to minors within 60 days or face potential criminal or civil action. The agency also plans to look closely at how kid-friendly e-juice flavors may be contributing to the spike in use.

“E-cigs have become an almost ubiquitous – and dangerous – trend among teens,” FDA commissioner Dr. Scott Gottlieb said. “The disturbing and accelerating trajectory of use we’re seeing in youth, and the resulting path to addiction, must end. It’s simply not tolerable.”

Science and public policy have bounced back and forth for over a decade, as different studies produce different – and sometimes contradictory – results. Let’s take a look at the debate over the years:

2003 headline: Invention of e-cigarettes

The inventor of the electronic cigarette, Hon Lik, smoking his invention in Beiijng on May 25, 2009.
FREDERIC J. BROWN/AFP/Getty Images
The inventor of the electronic cigarette, Hon Lik, smoking his invention in Beiijng on May 25, 2009.

Three pack-a-day smoker Hon Lik, a 52-year-old Beijing pharmacist, created the first successful electronic cigarette after his father, another heavy smoker, died of lung cancer. By 2007, e-cigarettes were marketed in Europe and the United States by manufacturer Ruyan as a way to safely stop smoking tobacco.

Hon was not the first person on record to have the idea for an electronic non-tobacco option. Herbert A. Gilbert filed for a patent in 1963, in an era when tobacco smoking was widely accepted and the health risks were less apparent.

In September 2008, the World Health Organization announced that marketers should immediately remove any claims that e-cigs are a “safe and effective smoking cessation aid” because there is “no scientific evidence to confirm the product’s safety and efficacy.”

2008 headline: WHO slams e-cigarette marketing

Soon after, a study funded by e-cigarette manufacturer Ruyan declared the product to be 100 to 1,000 times less dangerous than smoking tobacco, adding that when using its device, nicotine is “apparently not absorbed from the lung, but from the upper airways.”

2010 headline: The battle heats up

In May 2009, the Food and Drug Administration released the results of a test of two US e-cig brands, NJOY and Smoking Everywhere, that found “very low” amounts of nicotine in cartridges labeled as nicotine-free. In July, an FDA news release discouraged the use of e-cigarettes, saying they contain carcinogens and an ingredient used in antifreeze, diethylene glycol.

Another concern of the FDA’s: E-cigarettes are often marketed and sold to youngsters who, intrigued by the many flavors such as chocolate, bubble gum and mint, might easily adopt a smoking habit as a result of trying the devices.

Vape supporters counter that diethylene glycol was found at a very low, nontoxic level of 1% and that the carcinogens are at the same levels as other FDA-approved nicotine cessation products, like patches and gum.

By the end of the year, Amazon and Paypal restricted the sale of e-cigs on their websites.

2011 headline: Interest in vaping for smoking cessation is high

Science began to ramp up studies on the topic. Several studies found that interest in e-cigarettes was high among the American public: Google searches for e-cigs were higher in the US than any other nation.

A questionnaire of 3,500 e-cigarette users found that most vaped because they though it less toxic and cheaper than tobacco, and would help them quit or cut down on tobacco smoking. Most ex-smokers (79%) in the study were afraid they would relapse if they stopped using e-cigarettes. The study didn’t examine the safety of the product.

Another, much smaller email study of 216 e-cigarette users found that 31% were tobacco-free at six months, and 66% were able to cut back on the number of conventional cigarettes they smoked. A still smaller study of 40 smokers also found that adding e-cigarettes helped smokers reduce the number of traditional cigarettes they smoked each day.

2012 headline: E-cigarette use doubles in adolescents

The US Centers for Disease Control announced that e-cigarette use among middle and high school students doubled between 2011 and 2012, mirroring a similar increase in adult use. Most alarming for policy makers: CDC concerns that vaping among adolescents may serve as a gateway to tobacco use.

Use among middle and high school students doubled in a year.
Phanie/Alamy
Use among middle and high school students doubled in a year.

To measure nicotine delivery, United Kingdom researchers tested 16 e-cigarettes with an automatic smoking machine and found wide variations in nicotine levels per puff, ranging from 0.5 to 15.4 milligrams. In contrast, the typical level from a tobacco puff ranges from 1.54 to 2.60. The wide variation between e-cigarette brands led researchers to question how well they can function as a nicotine replacement device.

2013 headline: Do e-cigs really help smokers quit?

Several 2013 publications showed minimal evidence that e-cigarettes help smokers quit. A cross-sectional study of 1,836 tobacco smokers found a significant association with e-cig use and “unsuccessful quitter” status but none with “quitter” status.

Another study of callers to state tobacco quitlines found e-cigarette users significantly less likely to be tobacco-free seven months after they first tried vaping, compared with participants who never tried e-cigarettes.

A New Zealand Health Research Council study of 657 smokers found e-cigarettes modestly effective in helping smokers quit. Interestingly enough, it didn’t seem to matter whether they contained nicotine. But the results were similar to FDA-approved nicotine patches.

Some researchers worried that e-cigarette use might distract smokers from proven safe and effective methods for kicking their tobacco habit. “It’s filter tipped, low tar, déjà vu all over again,” Dr. Frank Leone and Dr. Ivor Douglas wrote in their essay “The Emergence of E-Cigarettes: A Triumph of Wishful Thinking over Science.”

2014 headline: Poison center calls skyrocket

The CDC released data showing that the number of calls about nicotine e-juice to poison centers rose from a scant one call per month in 2010 to 215 calls per month in 2014. More than half of the calls involved children under the age of 5 ingesting, inhaling or getting the substance in their eyes or on the skin.

E-liquid looks colorful and the flavors are attractive to children.
Spencer Platt/Getty Images
E-liquid looks colorful and the flavors are attractive to children.

A study of over 75,000 Korean adolescents found e-cigarette use to be strongly associated with current and heavy traditional cigarette smoking. Data from the CDC found that the use of e-cigarettes among US high school students grew from 4.5% in 2013 to 13% in 2014. In that same period, use grew among middle-schoolers from 1% to 4%.

In regard to safety, a study found that e-cigarettes contain tobacco-specific nitrosamines and heavy metals like cadmium, nickel and lead but that the levels were nine to 450 times lower than traditional cigarettes. The effect on lung function of glycol derivatives found in e-cigarettes was also much less than conventional cigarettes.

Still, researchers weren’t convinced. “Although these data suggest that e-cigarettes may be a safer alternative to conventional cigarettes,” reviewers Bradley Drummond and Donna Upson said, “there are no data regarding the long-term cancer risk associated with low-level exposure to the detected carcinogens. Similar to cancer risk, there are no published data describing the long-term lung function or cardiovascular effects of e-cigarettes.”

2015 headline: Vaping could be dangerous but perhaps a quitting aid