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What would you do to keep teens from vaping? Health Canada wants to know.

On Thursday, the federal agency issued a national plea for help with what has become a runaway public health problem.

The phenomenon took less than a year to reach what Canada's chief medical officers this week described as an "alarming number of youth vaping in Canada."

Rewind to last spring and the picture was completely different. Back then, many Canadian kids still hadn't seen the new high-tech vaping gizmos that could almost perfectly mimic the nicotine hit of a cigarette, with the stealth of a computer accessory and a bonus zest of fruit flavours.

The seismic shift in the nicotine market occurred quietly last September when the Juul vape stick was officially launched in Canada, quickly dominating with an innovative delivery system using nicotine salts that give a faster nicotine hit to the brain than older vaping products.

Tobacco companies seized the moment. Tobacco giant Altria purchased a share in Juul, and British American Tobacco, the parent company of Imperial Tobacco Canada, launched its own version — Vype — also with nicotine salts in a variety of fruit flavours.

We now truly have a product that can compete with cigarettes in both a good and bad way. - Prof. David Hammond, University of Waterloo

It's the first time in the history of nicotine use that a non-burning product can match the inhalation experience of a traditional cigarette.

"We now truly have a product that can compete with cigarettes in both a good and bad way," said David Hammond, a public health professor at the University of Waterloo who studies nicotine use.

Tobacco-industry dream and public-health nightmare

Canada's own tobacco industry documents released through the courts reveal that industry executives have long dreamt of a day when a new product might come along that would "act as an acceptable alternative to both cigarettes and quitting."

"Perhaps we could develop cigarettes that would not have to be lighted with a flame … that would burn without smoke … and that would not leave butts. Ridiculous? Perhaps," wrote one industry executive in 1976.

"But so was Jules Verne's idea of an underwater vessel called Nautilus or of a manned trip to the moon. We could give it a try."

Before youth start smoking again, this is where we really want to get the message out so we are not pulling youth back into smoking. - Dr. Theresa Tam, chief public health officer of Canada

Today, new tobacco documents reveal that the realization of this dream has triggered a nicotine renaissance.

"Back in a growth industry" is how British American Tobacco (BAT) described the current market in a presentation to investors last month, as "new categories attract more consumers and generate more revenue growth."

In one graph, the company reports that less than half of BAT's new vaping customers are smokers switching to vaping. The majority are new users who have never tried vaping before.

"They are adult consumers who classify themselves as not using vapour before, and therefore new to this category, but it is a little one-dimensional in the sense it doesn't tell you the whole picture," BAT spokesperson Annie Brown said in an email to CBC News.

Brown said the data doesn't reveal whether the new users are former smokers who might be returning to nicotine use through vaping instead of smoking.

The BAT presentation describes the emergence of "poly-usage" — a cigarette in the morning, a vape at the office during the day — and, after dinner, perhaps another one of the new "potentially reduced risk products" (PRRPs), which include vapour devices, heated tobacco devices that use tobacco to generate a nicotine-containing aerosol, and new forms of nicotine pouches for the mouth.

Added up, BAT reports that "usage occasions are increasing."

A slide from a British American Tobacco presentation to investors describes "poly-usage," where customers use different nicotine-delivery products in various situations throughout the day. (British American Tobacco )

"Context is important here, too," said Brown. "PRRPs are a very different experience to smoking, and therefore, if adult smokers are to transition from cigarettes to using PRRPs (which, based on the science available to date, is potentially a good thing), then it is important that there are opportunities to use these products to drive consumer acceptance of them as alternatives to cigarettes."

'Poly-usage' a new health challenge?

For public health officials, "poly-usage" creates a new health policy challenge.

Canada's chief medical officers of health said this week that vaping while still using cigarettes "has little benefit in reducing health risks."

In the same statement, the Council of Chief Medical Officers of Health called for "aggressive steps to protect our youth from these products."

"Before youth start smoking again, this is where we really want to get the message out so we are not pulling youth back into smoking, renormalizing smoking," Dr. Theresa Tam, Canada's chief public health officer, said in an interview.

All of this might have been different if Health Canada had chosen to regulate vaping more strictly when the new federal vaping law came into effect last May. Before then, it was illegal to sell any vaping product containing nicotine.

After the law took effect, it was still illegal to sell vaping products to anyone under 18. But by Christmas, high schools were removing bathroom doors to discourage in-school vaping. Teachers were seizing vape sticks in class.

Meanwhile, regulators are scrambling to catch up in the midst of a data vacuum, because research surveys that track youth smoking and vaping in Canada aren't due to report for months.

David Hammond is a University of Waterloo professor who studies tobacco use. (Craig Chivers/CBC)

At the University of Waterloo, Hammond has one of the only up-to-date snapshots of the Canadian vaping scene. His data still hasn't been publicly released, although he has shared it with Health Canada. The numbers show that youth vaping has risen dramatically and that it might even be linked to an increase in youth smoking.

"Our study raises the question that we could be going in the wrong direction on smoking rates," Hammond said. "But I don't think it needs to be a major piece of this story, because there's enough reason to act on vaping alone."

Hammond's data mirrors results from U.S. surveys that prompted the FDA to declare a youth-vaping epidemic.

And now, federal health officials seem to be having a regulatory change of heart.

"Canada's important public health achievements are at risk of being eroded, if nicotine dependency through vaping becomes normalized among young people, particularly among those who would not otherwise have tried smoking," Health Canada said in the consultation document released on Thursday.

So what's the plan?

So far, Health Canada has launched some scary ads warning young people about the risks of a lifelong nicotine addiction. In February, it proposed a series of new rules for the promotion and sale of vaping products.

And now the agency is asking Canadians how they feel about even tougher rules that could ban certain flavours and reduce nicotine in vaping products. The public consultations are open until May 25.

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