As It Happens

E-cigarette bans are 'a tremendous overreaction' to vaping-related illnesses, says doctor

Dr. Michael Siegel says black market THC oil is most likely to blame for the recent rash of vaping-related illnesses and deaths — not flavoured e-cigarettes.

Dr. Michael Siegel says black market THC oil is most likely to blame for illnesses and deaths

A man smokes an electronic cigarette in the street in Milan. (Gabriel Bouys/AFP/Getty Images)


For the first time in Canada, there's a case linking severe lung disease to vaping.

Public health officials in London, Ont., say that a high school-aged student recently fell ill and was put on life support after using a vaping device.

It comes at a time when respiratory illnesses related to e-cigarette products are sharply on the rise — and as various jurisdictions are struggling to get a handle on the problem. 

In the U.S., seven people have died from vaping-related illnesses. That has prompted New York state and Michigan to ban flavoured e-cigarette products. India just announced it would be banning e-cigarettes altogether.

But some doctors say authorities are snuffing out the wrong culprit.

Dr. Michael Siegel, a Boston University community health sciences professor who runs the blog Tobacco Analysis, told As It Happens host Carol Off that THC oil-based vaping products are likely to blame for the rash of illnesses. Here is part of their conversation. 

As you know, authorities around the world are feeling the pressure to ban or to limit vaping. Do you think that's a good idea?

I think that there has been a tremendous overreaction to what's going on in the United States.

We've seen about 400 cases of severe respiratory illness and about seven deaths. And what authorities are not telling people is that in the overwhelming majority of these cases, what is associated with the illness is not vaping electronic cigarettes, but actually vaping illicit marijuana vape cartridges.

So these are THC oils that people are vaping that are getting into the lungs and causing these diseases.

But do we know that for a fact? Are you saying these [people who got sick] were vaping THC and they weren't vaping tobacco?

In about 80 per cent of cases the CDC itself has acknowledged that the individual patients were vaping cannabis THC oils. Some of those patients were also using nicotine liquids as well.

But the one thing that ties together the overwhelming majority of these cases is the use of THC.

And we know that there was a contaminant called vitamin E acetate oil that was found in all of the New York cartridges, THC cartridges, that were tested. And we know that vaping oil is extremely dangerous to the lung.

What we are hearing in the United States and in Canada and other places is that there are warnings now for people not to use e-cigarettes. The Centres for Disease Control in your country has warned users against it. What is that based on in the way of data or information?

I think the CDC is conflating two different problems. One is the problem of youth e-cigarette use, which is certainly a problem, and the other is these respiratory diseases.

And the problem when you conflate the two is that it really confuses the public. And if the CDC were just to simply say, "Hey, don't vape marijuana," I think it would do a lot more to protect people's lives.

E-juice, used in e-cigarette vaporizers, is displayed at Smoke and Gift Shop in San Francisco, Calif. ( Justin Sullivan/Getty)

But if we don't know, if there is so little data, and so few studies and tests, and this phenomenon of people becoming sick and even dying from this is going on, isn't it incumbent on the authorities to say let's just step back from this? Especially given the number of young people who are vaping at this point.

In an outbreak like this, you don't want to generalize. You want to be as specific as possible.

In public health, we have what's called the precautionary principle, and that basically says you don't wait until you have definitive evidence before you warn people.

When you have reasonable evidence to suspect that something is causing a disease, you warn people. And so I think right now the CDC has reasonable evidence to conclude that there's definitely something wrong with these THC cartridges that are being bought on the black market.

What are the consequences if people who are smoking e-cigarettes now decide that they're not going to do that anymore and they're going to heed this warning and figure they shouldn't be vaping tobacco? Does that mean that they stop smoking?

No. I mean, unfortunately, smoking and nicotine are very, very highly addictive.

We know that the overwhelming majority of smokers or ex-smokers who are now vaping, if they stop vaping, they're most likely going to go back to cigarette smoking. And that's the last thing that we should be doing in public health.

We know that the vaping industry or the e-cigarette industry has targeted young people, much the same way as the cigarette tobacco industry did in the last decades. And there's so many young people, even high school kids, even grade school kids, who are into vaping. What happens if now they are now hooked on tobacco through e-cigarettes? What happens to them if they stop vaping?

I think that kids use whatever's in their network.

I don't think that they're particularly picky about what they're vaping. So what's going to happen is if we ban flavoured e-liquids, then they're just going to start using other types of liquids, namely the THC liquids that are just incredibly easy to obtain. You can just order them over the internet.

And I think that might actually make this outbreak even worse than it is right now.

You mentioned the flavoured e-cigarettes. It's like confections. They are candy flavoured products. Some have suggested that it might be whatever is in the flavour itself that is the problem. Is that possible?

It's very unlikely because there are many, many different flavours on the market and they've been used for many years and we haven't seen a problem.

Why are we seeing these cases this year, rather than any of the past nine years? 

One thing that has changed is that a new type of thickening agent is being used to dilute THC distillates from cannabis, and that is vitamin E acetate oil.

It's found its way into hundreds of thousands of vape cartridges over the past few months. You know, it seems too coincidental that we're seeing this outbreak just after this major change was made.

Many of these patients have something called lipoid pneumonia, which is essentially the lungs just fill with oil.

It makes sense that if they're vaping largely an oil-based product that that could cause lipoid pneumonia. Pretty much all nicotine e-liquids are not oil-based. They're water-based. And so we know for sure that those products can't cause lipoid pneumonia.

So the pieces of the puzzle are fitting together and they're all pointing in one direction.

Written by Jeanne Armstrong and John McGill. Interview produced by Jeanne Armstrong. Q&A has been edited for length and clarity. 


To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.

Become a CBC Member

Join the conversation  Create account

Already have an account?