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The Canadian Paediatric Society is calling for a ban on flavoured e-cigarettes after the U.S. Food and Drug Administration (FDA) sounded the alarm on a rise in teen vaping, describing it as an "epidemic."

The number of U.S. high school students who say they've used e-cigarettes in the last 30 days is 78 per cent higher this year than last year, according to the latest National Youth Tobacco Survey, a joint study by the FDA and the U.S. Centers for Disease Control and Prevention (CDC). For younger students in middle school, the increase was almost 50 per cent.

It all adds up to more than 3.6 million American minors using e-cigarettes in 2018 — 1.5 million more than in 2017, the FDA says.

"These data shock my conscience," said FDA Commissioner Dr. Scott Gottlieb in a statement, noting that a big problem appeared to be "youth appeal and youth access to flavoured tobacco products."

The variety of candy, dessert and fruit flavours now available make vaping a sweet proposition for young people, says the American Academy of Pediatrics.

Like their Canadian colleagues, American pediatricians wanted a total ban on flavoured e-cigarettes. They were disappointed when, despite Gottlieb's dramatic remarks, the FDA didn't issue one.

"Flavours are really among the most compelling reasons that kids use these things. There have been some really robust studies," said Dr. Rachel Boykan, a pediatrician in Stony Brook, N.Y., and member of the academy's tobacco control executive committee.

Adolescents are especially susceptible to nicotine addiction through vaping, says Dr. Rachel Boykan, a pediatrician on the tobacco control executive committee of the American Academy of Pediatrics. (American Academy of Pediatrics)

Rather than an outright ban, the FDA said it is restricting where flavoured e-cigarettes can be sold. With the exception of mint or menthol, U.S. stores can only sell flavoured vaping products in areas where people under the age of 18 can't enter.

So will Health Canada, which previously banned menthol cigarettes in an effort to curb tobacco use among youth, heed the call from pediatricians when it comes to e-cigarette flavours?

In short, no.

"While Canada and the U.S. have both recently regulated the vaping marketplace, the situation is not the same in the two countries," Health Canada spokesperson Maryse Durette said in an email.

Health Canada bans "the promotion of flavours that may be appealing to youth, such as candy and dessert flavours," Durette said.

But it will not ban the flavours themselves, she said. And it won't implement restrictions on where those flavours can actually be sold, as the U.S. did. In addition to dedicated vaping stores, the products are available in Canadian gas stations and convenience stores.

'Less harmful alternative'

Restrictions on flavours could hinder the point of approving vaping products in this country in the first place, Health Canada says — which is to reduce cigarette and cigar smoking.

"Flavours help make vaping liquids palatable to adult smokers seeking a less harmful alternative to tobacco," Durette said. "Therefore, the use of flavours in vaping liquids is not prohibited under the TVPA [Tobacco and Vaping Products Act]."

The act prohibits retailers — in stores or online — from selling any kind of vaping products to youth under 18.

"Health Canada has a rigorous compliance and enforcement program in place to monitor vaping manufacturers', importers' and sellers' compliance," said Durette.

Not good enough, says the Canadian Paediatric Society.

"While we are pleased that several of our recommendations — specifically the bans on e-cigarette advertisements and merchandise that appeal to youth — are reflected in current Canadian laws, even stronger rules and enforcement are needed," the society said in a statement.

Risk to teens

Whatever benefits e-cigarette flavours may offer adult smokers are outweighed by the harm they can do by attracting minors, argues Boykan.

Adolescents are more vulnerable than adults to addiction, Boykan said, and the e-cigarette "pods" that are popular now — such as those produced by vaping giant Juul Labs — have high concentrations of nicotine.

"They like this thing, they tried it, now they're addicted," she said.

In addition to the risk of addiction, nicotine is "really not safe for the adolescent brain," Boykan said, noting that research suggests it has potential long-term effects on cognition and memory.

Youth <a href="https://twitter.com/hashtag/ECigarette?src=hash&ref_src=twsrc%5Etfw">#ECigarette</a> use surged during 2017-2018, erasing a previous decline. E-cigarettes contain nicotine, which is addictive and can harm the developing adolescent brain. Learn more in <a href="https://twitter.com/CDCMMWR?ref_src=twsrc%5Etfw">@CDCMMWR</a>: <a href="https://t.co/r6BD6iQ7L1">https://t.co/r6BD6iQ7L1</a> <a href="https://t.co/unSo1NOc3u">pic.twitter.com/unSo1NOc3u</a> —@CDCDirector

Another major concern is that once teens become dependent on nicotine, they may also turn to traditional cigarettes, threatening the trend that has seen youth smoking steadily decrease in both the U.S. and Canada.

"Health advocates have seen incredible success in curbing tobacco use and exposure to the harmful byproducts of smoking," the Canadian Paediatric Society said. "Thoughtful legislation is needed to ensure that e-cigarettes do not undo much of that progress."

Health Canada says it shares those concerns — but also issued a statement following the FDA's findings this week that said "Canada has not seen a similar spike in the use of vaping products by youth."

To back up that assertion, it cites the latest results of the Canadian Tobacco, Alcohol and Drugs Survey, saying that six per cent of Canadian youth between 15 and 19 reported recent use of e-cigarettes in 2017 — showing no increase from two years before.

A high school student in Cambridge, Mass., displays a vaping device that she has decorated with stickers. Schools and health officials across the U.S. are struggling to curb what they say is an 'epidemic' of underage vaping. (Steven Senne/Associated Press)

But that data was collected months before the vaping market opened up in Canada last spring, ushering in the recent arrival of Juul, which is a major U.S. supplier of sleek e-cigarette products.

Both the FDA and the CDC have specifically named Juul's products as appealing to minors.

Is it possible that there's been a dramatic increase in youth vaping that just hasn't shown up in Health Canada's numbers?

"Health Canada has a robust surveillance system in place, which will continue to closely monitor youth vaping in Canada as new products become available," Durette said in response to that question.

The department started its latest round of data collection for vaping and tobacco use among students in Grades 7 to 12 in October, she said.

The Canadian Paediatric Society doesn't want to wait for the results.

"The burden of clearly and accurately documenting the level of risk associated with e-cigarette use should be carried by the industry, and the government should not loosen or remove any precautionary restrictions until those risks are known," it said.