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Consider it a real life public health experiment on the effects of inhaling nicotine vapour.

The results won't be known for decades, but vaping is poised to take off in Canada now that it's officially legal to sell nicotine vaping products under the federal Tobacco and Vaping Products Act.

And with the law in place, Big Vape has landed. On Thursday the U.S. vape company Juul Labs announced it's coming to Canada.

"The company's mission is a simple one: impact the lives of the world's one billion adult smokers — and the five million in Canada — by creating a satisfying alternative to combustible cigarettes," the company said in a news release.

"This is potentially a very big deal," said David Hammond, a University of Waterloo professor who studies tobacco use. He's been watching Juul for a while.

"Basically in the last 12 to 16 months Juul has absolutely taken off and is now dominating the vaping market in the U.S.," he said. "There's something about this product that's different."

The Juul vape stick looks like a small memory stick and it can be recharged using a computer USB port. And Juul also uses a unique form of nicotine salts that deliver a stronger nicotine hit, one that more closely simulates the experience of smoking a cigarette.

"Does the very high level of nicotine and the way it's delivered, does that change what we've known about e-cigarettes which is lots of kids try them but very few use them regularly unless they also smoke? That is one of the most important questions that we can't answer just yet," said Hammond.

Juul insists it doesn't want kids to use its product and the company is requiring all of its Canadian retailers to follow provincial regulations and demand ID to avoid selling to minors.

But Juul's appeal to teenagers has created controversy in the U.S. prompting the Food and Drug Administration to crack down on retailers selling Juul to young people. The agency is also investigating the company's marketing practices.

Here in Canada, there are rules about how vaping products can be advertised, including limits on lifestyle ads and images that appeal to children.

But Juul's popularity has been fuelled by social media and it's not clear if there is any way to stop the same thing from happening here.

David Hammond is watching to see how vaping advertising and marketing take off in Canada. (Craig Chivers/CBC)

Health Canada has a plan. It's looking for a contractor to launch an "influencer marketing program" on the health risks of vaping products.

"The national experiential marketing events program is intended to connect with youth across Canada," said Health Canada spokesperson Sindy Souffront, in an email. "The program also aims to equip parents and teachers with the tools and resources they need to support conversations and discussions about the health risks of vaping products."

Vaping is a tricky issue for public health advocates. Most agree that vaping is safer than smoking.

Risk of relapse in ex-smokers

"Smoke is about the most potent brew of toxins that you could ever inhale," said Hammond.

But what are the health risks of vaping for people who would have never smoked?

"We won't know what the actual risks are for another 10 or 20 years," said Hammond.

And what happens as the vaping industry tries to expand its customer base?

"We are very concerned," said Rob Cunningham, senior policy analyst with the Canadian Cancer Society. "There's a high and growing use of e-cigarettes. There's a risk that ex-smokers could be appealed to relapse, people who have quit altogether."

"We certainly don't want kids to get addicted to nicotine."

The evidence so far suggests that about a quarter of Canadian kids have sampled e-cigarettes. One study by Hammond's group showed that youth who tried vaping were more likely to also try smoking.

Marketing splash

"Smoking and e-cigarette use is very highly correlated," said Hammond. "But most of that has to do with kids that try one risky behaviour do another one."

"To date e-cigarettes haven't really developed nicotine addiction in kids. But there's no guarantee that will stay the same in the future with these other products."

The arrival of Big Vape is a potentially profound change in what is a rather pristine Canadian vaping market.

"We just haven't had even any big branding like this out there and there's been very low levels of marketing so it's almost like this is coming into calm waters and we'll see how big a splash it makes and what the ripple effect is," said Hammond.

In Canada, the vaping industry is divided. On one side are vaping shop owners and small manufacturers who want to see vaping products confined to specialty shops.

"We're not promoting this as a lifestyle. This is an alternative to those who wish to find a less harmful alternative to smoking a cigarette," said Marc Kealey, with the Canadian Vaping Association.

On the other side are the big tobacco companies that have started selling e-cigarettes along with regular tobacco products in convenience stores. Rothman, Benson & Hedge's IQOS product uses heated tobacco rather than a nicotine liquid.

"Rothman, Benson & Hedges is looking at the vaping market closely, and clearly there is an opportunity for vaping products," said managing director Peter Luongo, in a statement.

"Right now we are focused on heat-not-burn and IQOS in the Canadian market."

In most provinces, there are restrictions on how vaping products can be sold and where they can be used.

But in Ontario at the moment, vaping products are sitting open on shelves beside candy in some stores and gas stations. That's because regulations to prohibit those displays were put on hold by the new provincial government.

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