B (3:10)

That's what the authors have argued. They've said that their results or their review sort of contradicts this idea that vaping is generally safer than smoking. When vapes first came onto the scene, you know, say a decade ago, they were very much promoted as a safe alternative to smoking. We know that in Australia you can go and get a vape legally through a pharmacy as a smoking cessation device. Will say at the outset that for people who are trying to quit smoking and, and vaping through a pharmacy to get off smoking, they should absolutely, absolutely keep doing that. I guess the unanswered question is, you know, we have so much, you know, hundreds, literally more than 100 years of research on cigarettes and how bad they are for you. We know they are absolutely shocking for your health. Two out of every three people who continue smoking cigarettes will die from smoking cigarettes. So we cannot say yet that vaping is worse than that. There's a lot of evidence that generally vapes have a lot less of these carcinogens in smoking and that sort of thing. What I think maybe the authors are trying to do here is kind of correct the record and correct maybe this idea that has been backed by the tobacco industry, by the way, that vaping is a lot safer than smoking. They just want to dislodge or challenge that idea, which is very much moved from, in about 2017, the language was very much, we still don't really know. Like, we're a bit concerned about the chemicals we're finding in vapes and the knock on effect to human health, particularly because so many young people use these products. We're not really sure what the researchers say they've identified is a real hardening of that language from questioning to more and more and more concrete concern that the signals that they're seeing in their animal studies and other experiments are showing that vapes probably are linked to cancer.

A (5:05)

Okay, and can you tell us a little bit about the effects that vaping has on the body and just how harmful it is. And does the study tell us anything that we didn't previously know on this count, or are there perhaps just harms that it does to us that have sort of fallen through the cracks that perhaps they just want to highlight to us, like, hey, hey.

B (5:22)

Yeah. So what they're really highlighting is that chemicals that we know pass into the body from vates include carcinogenic derivatives from nicotine, which do trigger and encourage tumors. There's also toxic chemicals and in particular, metals such as nickel that we know get into the body from, especially in cheaper vapes, where the coil sort of heats up and releases metals into the body. Obviously they are toxic. There's other substances like volatile organic compounds and also cytotoxic flavoring agents that vary really wildly between the different flavor profiles. So particularly with these unregulated disposable vapes that are still being sold illegally in Australia, you just really never know what you're consuming. But, you know, certainly there's been other really nasty chemicals such as formaldehyde and antifreeze found in these vapes. So one of the lead authors said that the studies that he reviewed has shown that these chemicals inflict things like oxidative stress, inflammation and genomic damage within tissues, which are known forerunners to cancer, and that experiments into vape aerosols have unequivocally showed DNA damage and long term changes in oral and lung tissues that are probably indicative of cancer development. So, yeah, there's nothing new there, but he is sort of like referring to all of these, bringing together all of these different experiments which seem to point very strongly towards a cancer link.

A (6:51)

Holy moly. Okay, and so, and let's talk about one of the most alarming quotes that really stood out in your piece. This was from Professor Bernard Stewart. He's the review's lead author at the University of New South Wales. And he said that sort of pitting vaping against smoking was like trying to study the safety of knives by comparing them to machine guns. So how was vaping ever originally marketed as a safer alternative to smoking?

B (7:16)

Right, yeah, well, that's sort of what he said. I mean, I asked him basically if that study design, which we see, which is like, you know, the vast majority of these studies study the health effects of vaping and compare them to people who smoke. And he is frustrated by that because he thinks it means that vaping is kind of, I guess, hid behind this claim for so long. Because, you know, in a lot of these studies, you do compare vaping and smokers and the smokers do have worse outcomes, you know, so. But that doesn't mean that the vapes themselves are safe. And that's where the machine guns and the knife metaphor comes in. Like, if you're doing a study into whether it's safe for a child to run around with a knife in the garden, you don't give it a machine gun and do the same experiment and see which one has the better outcome. You know what I mean? So we certainly need far more studies and far more evidence into vaping as a health risk in its own right, that's for sure.

A (8:13)

After the break.

B (8:14)

The case is that there is a growing number of young people who have only vaped, who've only picked up vapes and have never smoked. So it's very directly relevant to that population that just because it might be less bad than smoking, it does not mean that it's a safe thing to do.

A (8:36)

Okay, so I think you might have said before, but the importation of vapes has been illegal since the beginning of 2024. So why did another professor that you spoke to say it was going to be a, quote, nightmare to research vaping more broadly and its associated health risks?

B (8:52)

Yeah, so this was a guy called Distinguished Professor Brian Oliver, he's a nicotine researcher at the University of Technology, Sydney who has studied the effect of vape smoke on Rod. So I thought he'd be a good person to speak to. He wasn't involved in this study. And he basically said that, you know, this is a very early call and it is controversial and a lot of scientists, particularly overseas, have very much criticized it as saying that what these scientists are saying is not backed up by the evidence yet, basically. And that we're going to need that longer term epidemiological, definitive studies to be able to actually say really, really confidently that there is a link between vaping and cancer. The issue is that it's going to be in his quote marks, as you said, Sam, a nightmare to get there because not only do we have to wait for decades, but also vaping, at least in Australian context, is really unregulated. Like, I'm not talking about the people going to a pharmacy and getting a vape. Legally as a smoking society, that's sort of a different issue. But anyone could tell you that the vast majority of people vaping are using these illegal disposable vapes, like the gold alibabas that you see all of the other colorful ones. There's 100 different designs, there's literally thousands of different flavors from blueberry bliss to English marmalade to, you know, one day my housemate brought home like a, like a milk bubble tea, boba tea flavored vape. It was revolting. And all of these different vapes have completely different chemical makeup. So to be able to have a standardized study where you're looking at a group of people who are frequently vaping and comparing that to say, another group of people who have never touched a vape in their life, that's going to be really difficult because in that group of people who have been vaping, they are just exposing themselves to such different devices on a week to week basis which might have completely different heavy metals going into their body, completely different carcinogens, completely different flavors. And the other thing is, is that I spoke to an Australian vape researcher last year who said that even in the short time period that she's been studying these vapes, say over the last three or four years, the chemical makeup of them, even in the same kind of design or type of model, has changed massively. For example, the nicotine content in some of them has been ramped up by about 40% in about a year. And because nicotine really scorches the throat when you hit it through a vape to pack in more nicotine, the manufacturers will put in more, more and more nasty chemicals basically to try and disguise that burning nicotine feeling. So not only is there more nicotine, there's more, potentially more of these chemicals that we do not want in our body. So that variability is just one of the massive issues we have in terms of getting definitive evidence between vapes and bad health effects.

A (11:51)

Okay, and you just raised there that there's been a bit of backlash against this study. And before we started recording, you mentioned that a lot of this backlash has come from the uk. So is that what their backlash is? Essentially the evidence just doesn't support this claim or is it something else?

B (12:06)

Yeah, I mean, that's essentially what a lot of researchers in this space are doing. I mean the, the authors of the UNSW led study knew it was going to be controversial, but essentially a lot of their peers in the UK in particular have come out saying that the claim is misleading, essentially just because we don't have that high level human evidence yet. There was some criticism in terms of how they had compiled the studies and I guess the lack of analysis that they'd maybe done on the study that sort of just brought them together and then made this conclusion. But at least in some of these UK scientists view they hadn't done any analysis. They didn't, for example, and they were very upfront about this. They didn't actually identify how much vaping was likely to increase your risk of lung and oral cancer. They were just interested in saying, can we say with a reasonable amount of confidence that vaping is likely to cause lung and oral cancer? They've obviously said yes, but other scientists have criticised them saying that, you know, the fact that they can't necessarily put a figure on this just shows that it is a little bit of a shallow analysis. There was one professor from the University College London, Professor Leon Shahab. He said, while it is clear that e cigarettes expose users to harmful chemicals which may lead to later disease, I would urge against sensationalization of evidence. No one would argue that e cigarettes are entirely risk free. They should be used as a harm reduction product to help those who smoke to quit and reduce their risk of developing smoking related diseases. They should not be used by someone who has never smoked. However, this review does not offer a smoking gun that e cigarettes cause oral or lung cancer, nor does it make an attempt at quantifying this risk, which is unsurprising because the evidence is simply not there to allow for such an estimation. There's a couple of things to say there. One is that Australia and the UK have very different, I guess, public health approaches to vaping. The UK is a lot more in favour of this harm reduction model where they really encourage smokers to get off vaping. So a lot of people would see this study and be very concerned that people accessing vapes to get off smoking are going to stop doing that, which they absolutely shouldn't, because as far as we know, and I'll say it again, smoking is probably worse than vaping.

A (14:19)

So is that why? Because I'm so interested in, and you made that point that, you know, definitely, if you're using vaping to get off smoking, don't stop that because we know smoking is definitely worse. Is that it? So the fear is that if people stop vaping, which they've been using to stop smoking, if they stop vaping, they'll go back to smoking, which we know is worse.

B (14:38)

Totally, totally. That's the thing. But the case is that there is a growing number of young people who have only vaped, who've only picked up vapes and have never smoked. So it's very directly relevant to that population that, you know, just because it might be less bad than smoking, it does not mean that it's a safe thing to do.

A (15:00)

Right, okay. And just to wrap Up. Angus, you've spoken to a public health expert in Sydney who really kind of reflects this, right? She's saying that, yeah, long term smokers using vapes through a pharmacy to quit cigarettes should continue doing so. So it's sort of like she's kind of going against the Sydney study, I

B (15:18)

guess, a bit, A little bit. I mean, she, she thought the study was really interesting. This is Professor Becky Freeman from the University of Sydney School of Public Health. But, yeah, she did very much want to walk this line between saying that, yes, we should heed these early warnings in terms of vapes and cancer risk, but at the same time, we do not want to scare people off going back to smoking if they're using vapes as a smoking cessation thing. And the one other thing that I'll say just very quickly is that this study really gets to this issue, that there is a latency period of about 10 to 30 years, sometimes between exposure to a carcinogen and that cancer manifesting. So we may not get this definitive answer for decades and decades and decades. And there's this example where it actually took 100 years between the first study to be published finding a link between cigarettes and ill health and for the scientific community at large to accept that smoking causes cancer. 100 years for smoking. Right. We don't want to wait that long. It probably wouldn't take that long again this time, but it would take at least a couple more decades. So I think we're just starting to enter a new era of scientific debate where sometimes this will be really, really keen to start making these really definitive claims for the purpose of. Of public health. Whereas others are really going to try and urge caution and there'll be a lot more to emerge in this space.

A (16:35)

Wow. Well, it's so important that we are talking about it now because we're not going to be around in 100 years, Angus.

B (16:40)

No, we're not. Hopefully. I mean, yeah, maybe. Yeah, now that I've stopped vaping, it could be.

A (16:46)

Exactly. Well, we're so lucky you're reporting in this space. Thanks, Angus.

B (16:51)

Thanks for having me, Sam.

A (17:00)

Today's episode was produced by Josh Towers. Our executive producer is Tammy Mills, and our podcasts are overseen by Lisa Muxworthy and Tom McKendrick. If you like our show, follow the Morning Edition and leave a review for us on Apple or Spotify. Thanks for listening.