Air Quality Matters
Air Quality Matters inside our buildings and out.
This Podcast is about Indoor Air Quality, Outdoor Air Quality, Ventilation, and Health in our homes, workplaces, and education settings.
And we already have many of the tools we need to make a difference.
The conversations we have and how we share this knowledge is the key to our success.
We speak with the leaders at the heart of this sector about them and their work, innovation and where this is all going.
Air quality is the single most significant environmental risk we face to our health and wellbeing, and its impacts on us, our friends, our families, and society are profound.
From housing to the workplace, education to healthcare, the quality of the air we breathe matters.
Air Quality Matters
Air Quality Matters
#86 - Sir Stephen Holgate: Beyond the Lungs: How Air Pollution Affects Your Entire Body
When we talk about air pollution, we often think of it as an environmental issue – something that affects our skies and lungs. But the reality is far more complex and concerning. What if I told you that the particles you breathe in right now could be traveling through your bloodstream to every organ in your body?
Sir Stephen Holgate, a distinguished physician and leading expert in respiratory medicine, joins us to unpack the multisystemic nature of air pollution. With over 50 years of research experience and a knighthood for his contributions to medical research, he explains how particulate matter doesn't just irritate our lungs – it passes through them into our circulation, delivering harmful chemicals to our brain, heart, liver, and beyond.
"These very small particles get into the bloodstream and they circulate to every organ of the body," he explains. "It accelerates the aging process of those tissues or organs." This understanding has led researchers to now associate approximately 700 different diseases with air pollution exposure.
The conversation takes us from the scientific mechanisms of how pollution damages our bodies to the broader societal implications. We explore the inequalities in exposure, with disadvantaged communities bearing the greatest burden while having the least say in regulations. He makes a compelling case that breathing clean air should be considered a human right, much like access to clean water.
Perhaps most fascinating is the discussion of our body's barrier functions and how modern environments have overwhelmed these natural defenses. Sir Stephen Holgate shares remarkable research comparing traditional farming communities like the Amish, who have virtually no allergies or asthma, with genetically similar populations who adopted modern Western lifestyles. The difference? Their relationship with the natural world and the microorganisms that shape our immune systems.
Whether you're concerned about your health, interested in environmental justice, or simply curious about why asthma rates have skyrocketed in the UK, this conversation offers invaluable insights into how we might create healthier communities by cleaning up the air we all share.
Sir Stephen Holgate - Imperial Alumni Awards
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Welcome back to Air Quality Matters. We already have the tools and knowledge we need to make a difference to the quality of the air we breathe in our built environment. The conversations we have and how we share what we know is the key to our success. I'm Simon Jones and coming up a conversation with Sir Stephen Holgate, a British physician and leading expert in the field of immunopharmacology, respiratory medicine and allergies. He's a medical research council clinical professor of immunopharmacology at the University of Southampton and also serves as an honorary consultant physician at the University Hospital of Southampton NHS Foundation Trust. This is a slightly longer introduction than normal, but I think you'll understand why when you hear a little bit about Sir Stephen Holgate's bio. His research has been pivotal in uncovering the mechanisms behind asthma and related allergic diseases, and he has extensively studied the impact of air pollution, allergens and respiratory viruses in asthma exacerbation. Sir Stephen Holgate's contributions have been recognised with multiple awards, including the King Faisal International Prize in Medicine and national honours such as the Knighthood in the 2020 Queen's Birthday Honours for services to medical research. He is also a fellow of several prestigious scientific academies and continues to be an influential figure in advancing respiratory medicine, allergy research and environmental health. He was the lead medical expert who investigated Eloridu Kisidebra's case, the first in the world where air pollution was officially listed as a cause of death. His 2018 report established the link between the unlawful levels of pollution near Ella's home and her fatal asthma attack. He served as a star witness at the coroner's inquest, presenting data and medical records that led to the historic verdict that excessive air pollution had materially contributed to her death. His contribution was crucial for the coroner's conclusion and for driving public understanding that air pollution can directly cause individual deaths, breaking long-standing scepticism about attributing deaths to pollution at an individual level. He more recently led the Royal College of Physicians' landmark 2025 report, a Breath of Fresh Air, which underlines that air pollution, both indoor and outdoor, remains a serious and preventable public health issue. Overall, his leadership in these medical, legal and policy contexts has significantly advanced the public and governmental understanding of the health harms of air pollution, contributing to landmark rulings, public health recommendations and intensified calls for action at all levels.
Simon:It was an absolute pleasure to sit down with Sir Stephen Holgate. We talked about all of the above. He was very generous with his time and I really do hope you enjoy this episode as much as I did. Please don't forget to check out the sponsors in the show notes and at airqualitymattersnet. This is a conversation with Sir Stephen Holgate. The first question really just opens up this whole broader conversation that I know you're having at the moment about this multi-systemic nature of air pollution, particularly particulate matter, and what that really means for the community. Because I think the fascinating thing is when something becomes multi-systemic or when we've determined that it's multisystemic, it kind of automatically means it's multidisciplinary at the medical end of things. And we use this multidisciplinary or interdisciplinary trope often when we're talking about air quality, but again we don't drill down into what that really means. So I thought that would be a really interesting starting point for the conversation is what are we saying now when it comes to air quality, when we say we understand that air pollution is multisystemic?
Stephen:Yeah, well, let's start with the air itself, because obviously what we breathe in it keeps us alive, and it's the oxygen in the air that's the crucial bit here. Just over 20% of the atmosphere is made up of oxygen, and the breathing cycle, which takes in air on a daily basis many, many, many, many hundreds of liters, is trying to deliver oxygen to the tissues of the blood, tissues in the blood, and and the important thing about this is that that has always been the case since mammals occupied the Earth. But as a consequence of what we and others have done to the Earth, the air doesn't just contain oxygen. It contains other elements, but particularly pollutants, some of which are gaseous and some of which are made up of very small particles. And it's these man-made in large part, and these man-made materials which have entered the atmosphere over the last centuries which make up the pollutants that we breathe in. And the key to this is that some of those pollutants, the gases in particular, are irritant, and we all know when we walk into a room where there's irritant gases in the room, we cough and we can sense it at the back of our throats and a tightness in the lungs, and gases such as nitrogen dioxide, sulfur dioxide and ozone, which are air pollutants which we commonly talk about, are these irritant gases and they tend to operate by triggering nerves in the lung and making you feel breathless or making you cough, making your chest feel tight. But I think in the last 20-odd years 25 years what we've come to learn is that air pollution extends far beyond the gases to these small particles.
Stephen:And of course we knew about those in the 1950s when we had the terrible air pollution in London and in other cities related to the Industrial Revolution and the burning of coal. But since the Clean Air Acts in 1956, when coal burning was reduced, we know that this pollution fell very dramatically and we thought the problem was solved. And the reason we could see air pollution is the fact that those particles in the air could see. Air pollution is the fact that those particles in the air, which were made up of a mixture of carbon as well as other chemical substances, were visible to the eye and would reflect light. And if you're as old as I am, you can remember the days when you would go out in a foggy day with a torch and you could see the torch beam reflecting back to you because of the particles in the air. So these particles we thought we got rid of with the Clean Air Act. Well, we did, in terms of the smoke-related carbon particles from burning coal. But of course, what's happened since then, back to 1956 when we had the Clean Air Act? What's happened since then, back to 1956, when we had the Clean Air Act, is that other pollutants have gradually replaced what we used to be able to see as these coal-related pollutants, and these ones obviously are the ones that we're now becoming increasingly concerned about.
Stephen:And, as I mentioned, over the last quarter century we've come to learn that these small particles not only come into the lung, where they can obviously set up a local reaction and cause some inflammation and I'll talk about that a little later but they can also pass through the lining of the lung into the circulation, into the circulation.
Stephen:And so this is the serious bit about air pollution really is that these very small particles get into the bloodstream and they circulate to every organ of the body, and since these particles are made up usually are made up of carbon, obviously at the center usually, but then a whole load of other chemical substances on the surface and embedded in the center usually, but then a whole load of other chemical substances on the surface and embedded in the particle, which are carried with the particle as it circulates into the tissue.
Stephen:So when these particles end up in the brain or in the liver, or in the kidney, in the heart, they are then going to release those chemicals in those environments.
Stephen:And so it is hardly surprising now that we're recognizing, through some really good biomedical and epidemiological research, that this particular air pollution is associated with many different diseases beyond lung disease, which is obviously the organ that sees the air pollution first.
Stephen:And it is the delivery of those chemicals into the tissues over a prolonged period of time which sets up an inflammatory reaction and damages those tissues and, in the shortest possible way of kind of capturing what that does wherever it is, whether it's the brain, heart, kidney, liver, wherever does, wherever it is, whether it's the brain, heart, kidney, liver, wherever it accelerates the aging process of those tissues or those organs. So what we've got now is an environmental insult reaching the bloodstream, ending up all around the body, accelerating the aging process through the release of these chemicals, and the fact that the tissues are having to try and fight these chemicals locally where their particles are deposited. So I think that's the concern, and some of the most recent research would suggest that up to 700 different diseases now are associated with particulate and gaseous air pollution, with particulate pollution by far and away being the most important.
Simon:I think what's really interesting here is this recognition and I think it's quite a common sense, plain English recognition that I think perhaps society needs to get its head around a little better, and that is the lung as an incredibly efficient delivery system for chemicals and heavy metals and viruses and bacteria and so on into the body.
Simon:I think there's been a light switch has gone on from that, from the pandemic, obviously, and the risk of the air that we breathe. From a biological perspective, vaporized medicine at two and a half microns below you know, as a very efficient way of getting medicine right to where it's needed. So I think, once people's heads that that light switch goes on and you go, yeah, okay, I get, it's not just about depositing silica or carbon on the lungs or tobacco smoke or and so on, know that. I think people's people have got well used to understanding that breathing in particles has like a a deposit impact on the lungs, but recognizing that actually it's a delivery mechanism that bypasses all of the you know, our dermal protection on our skin, our gut protection in in ingestion. We've got some pretty sophisticated mechanisms for protecting us against environmental insult, but the lungs don't have that and it is. We've created this environment where we're effectively breathing in heavy metals, phthalates, gases, plastics, all sorts of things, and our lungs have become this delivery mechanism for them.
Stephen:Yeah, absolutely. And you know, I think you mentioned tobacco smoking, and that's quite a good example actually, because obviously people smoke because they get a sense of satisfaction. That's because the nicotine is absorbed into the circulation, which is the brain, but of course, as you correctly pointed out, all the carbon particles, lots of them, get deposited in the lung and over time causes the lung damage, whereas the stuff that gets in from cigarette smoke into the circulation, of which some does, causes the heart disease and other diseases that we also associate with tobacco smoking. So in some ways air pollution exposure is a bit like tobacco smoking in that you get the local effects on the lung, which does its best, as you said, simon, to stop the particles going any further, but of course the lung is only able to do that to a certain extent.
Stephen:Nuclear particles are so small that they can get between the cells. Then obviously you're treating particles like gas. The gas is going straight into the bloodstream. So that's where we are with all of this. It's the very small particles which is the one we're interested in and, as you pointed out also, as the particles get smaller and smaller and smaller, they become invisible, so we can't see viruses or bacteria, for example. But yet we know they're there. And you quoted COVID-19 as a good example, which is an excellent one, because obviously, in a closed space you are breathing in virus, but you can't see it, but it's in the air.
Stephen:And likewise with air pollution you can't see it, but it's in the air and we're breathing it in and it gets into the circulation and over a lifetime this accumulates. It's like tobacco smoke it accumulates and the body does its best to get rid of what it can, but sometimes it's overwhelmed. And that's why it's important that we regulate the pollutants that we breathe in, and that process is what all the air pollution debates are about. It's the regulation. How much of these chemicals are we going to allow ordinary people to breathe in? Because some would say that breathing clean air, just like drinking clean water, is a human right. So really we shouldn't have any toxic chemicals in the air, which we all know is going to be impossible, but at least we can try and get it as low as possible.
Simon:Yeah, there was a couple of things that sprung to mind then when you were speaking. The first one is that water and air analogy. I mean, one of the challenges with air is that it's often an uncontained system. We need to control the quality of the rainwater that we're collecting to drink. You know that it's it's. It's a it's an open system. That it's it. That's it. You know, air pollution knows no borders. As we know, it's a very difficult. It's not like a plumbing system where we can put a stamp of certification or approval on the quality. If we were just breathing piped air the whole time, it might be a slightly different maybe where we end up in some parts of the world, obviously.
Simon:Yeah, but there is that and I think it's an interesting one. And the other thing that sprung to mind was just how complex this suddenly becomes at a medical level. I understand that at a broad epidemiological level, the the broad associations at a cohort level we can make between exposure to certain factors and medical outcomes, um, but by the complex nature of the air we're breathing in, that, the vast, vast array of potentially heavy metals and and environmental factors that we we could be breathing in, and the complex nature of the systems in our body, that must be an incredibly complex puzzle to untangle toxicologically to try and figure out what is the impact of a heavy metal from brake discs, from traffic pollution on the liver or the kidney or the lung or the brain like. Is that work ongoing? Is this something that we're starting to get an understanding of? Actually, can we draw some lines toxicologically between some of these environmental factors and their direct impact on these tissues?
Stephen:well, I mean, there's some chemicals, of course, which have very dramatic effects, like like damaging DNA and then leading to mutations that cause cancer. So we associate that with some pollutants, just as we do with tobacco smoke. But, as you correctly say, it's the mixture of chemicals that is unloaded into tissues over time which is the issue. And of course that isn't a homogeneous one in its own right, because as we move around in the environment, sometimes during the day we're breathing a lot of these things in and other times we don't breathe any in. So, even across the 24-hour period, we've got these incredible variations in the load of chemicals that are breathed in in the breathed environment, if I could use that term, which end up in the circulation and get deposited in tissues, and that introduces its own complexity and we might return to that in a minute. But I think the body is adapted really over time, since we all emerged as mammals, to be able to cope with pollutants. I mean, remember when we had the dinosaurs stumping around the planets, you know there were volcanoes going off all the time, checking out pollutants everywhere and there was sort of bubbling mud and fermentation processes. So you know, over millions of years the mammalian body has adapted to be able to deal, as far as it is able to, with chemicals, to either detoxify them, that is, to make them no longer injurious to cells and tissues, or to transport them so they're excreted, either back into the gut or sometimes what happens is that they're excreted by the kidney into the urine. So we do have methods of coping with them. But the question really is, you know, with particles you can't really transport particles and then liberate them again and mobilize them. So these particles that I'm talking about really are the issue of the kind of slow release of chemicals in tissues. And there may be very many different chemical reactions that the particles with their chemicals initiate, but they all boil down to one or two things really. One is an accelerated oxidation mechanism. By that I mean that.
Stephen:Well, let me give you an example. If you cut an apple open and leave it exposed to air, it goes brown. That browning on the surface of the apple is oxidation. That chemical process is what air pollutants do when they get to these various cells and tissues. They release oxidants and they are the things that damage the cells. And though we can't see ourselves going brown like an apple does or a piece of fruit does.
Stephen:That is the process, and it's that oxidant pathway in different parts of the body, whether it's in the brain, in terms of dementia, or if it's in the kidney, in terms of reduced ability to be able to excrete substances, or liver, or in the heart. It is those processes, that process that leads to the damage in the long term. And once a cell is damaged, of course it needs to repair, and some tissues can repair remarkably well. I mean, we know that they're incredible, but other tissues can't. And I think this is the other bit of this equation when you start putting particles into parts of the body that can't repair well. A brain would be a good example here where if you damage the brain, it can't replicate itself and repair itself very well, so you have permanent damage over time, whereas if you've got other tissues, like the liver, for example, which actually is remarkably good at repairing itself, providing the onslaught isn't too heavy.
Simon:So some organs are going to be more susceptible to disease than others, and I think it's the susceptibility of the organ to the pollutant as much as the mechanisms that lead to the expression of accelerated disease process, and that's what we're now talking about talking about on the other side of that, then you've also got the complexity of the the environment as well, that that is a far more complex place perhaps than it was centuries ago or millennia ago, and certainly even, I'd imagine, decades ago, that we talk about often in the built environment of this grand chemical experiment. Just the nature of our environment is so much more complex than it ever was. Do we see that in air quality as well and the kind of things that we're finding ourselves exposed to?
Stephen:Indeed, simon, we do, and of course we treat the air like we do the water, which you talked about again earlier on, as a sort of commons. We can almost put anything into it without people even asking any questions, because it's everybody's right to have access to the air or to the water and they can do what they like with it. And we know the consequences of all of this. I mean, the water is a good example because it is a contained system and we know what putting stuff in the seas are doing to our wildlife in the seas and the biodiversity in our oceans. But likewise, when we start putting stuff on land, we know what it's doing to the soil and changing the structure of the soil by killing off various microorganisms. But likewise in the air, you know we're putting the stuff in the air and we're breathing it in. And you know a thousand or sorry, up to 3000 new chemicals a year are being developed which obviously are being released into the human environment and we have to deal with, and our bodies, I suppose, get to a point at the end of the day where they're running out of options or how to deal with all of this. And that's why, in a way, the, the elimination system, which was great for us maybe 500 years ago, when we weren't exposed to so many different chemical substances, probably are not fit for purpose now.
Stephen:And why are we getting into these sort of non-communicable diseases, which are linked to this changing environment that you talked about, where air pollution plays a role? But other things, you know diet, the stuff we drink, you know obviously get into our system as well. So it's not just pollution, but air pollution is one of those ones that, let's put it this way, it's kind of a hidden cause of disease. It's not obvious that this thing is going on all the time, because we can't taste it or see it or feel it, so it's just quietly there and causing this low level inflammation and damaging our tissues over time yeah, you mentioned that elimination thing.
Simon:With complexity comes an erosion of an ability to be able to say, right, okay, let's cut out or remove that risk from your environment or that risk from your environment. And this is one of the challenges with things like diet and exposure to environmental conditions is that the broad spectrum of potential agitators in that space and the the what's the best word I'm looking for, the vagueness of potential symptoms as a result means it's ripe for misunderstanding and very difficult to try and pinpoint exactly what the thing or combinations of things are causing a problem?
Stephen:yeah, yeah, absolutely, and that is, as you said, the complexity of toxicology in this area, understanding what is it in the air that is causing the particular type of damage. But I think if we look towards solutions as opposed to the causes of effects, then obviously, wherever the pollution is coming from, we can stop it from coming from there pollution is coming from. If we can stop it from coming from there, then we're likely to be able to stop a whole series of chemicals getting out and being breathed in. Incidentally and I think that's where the policy side starts to come in really is that it's very difficult to take one chemical at a time out of the atmosphere. I mean, if we know some are very, very toxic, like asbestos, for example. Obviously you know you can remove that by stopping people using it. I mean that's fine.
Stephen:But air pollution, unfortunately, as you said, is more complicated than that and it's the mixtures. And therefore, going to where these mixtures are coming from in the first place and thinking about regulating the emissions is really important. And keeping that inventory of emissions, list of emissions, up to date is crucial, because if you don't know what's going into the atmosphere, whether it be inside a building or outside a building, how can you possibly think about regulation? So it's very important that we know what we're putting into the atmosphere, so that, should things start to appear as they are with this epidemiology, you know which processes to start intervening. And that, in a way, is why there's been this incredible push towards diesel, because diesel fuel, when it's burned, causes more particles of the toxic nature we've been talking about than other forms of combustion in engines, and therefore cleaning that up would seem to be quite a quick route for removing something that has now been identified as a major toxic principle of the particles that we breathe in.
Simon:I thought it was really interesting and this is what I really like about someone that has to straddle the science with actually implementing outcomes. And we see this in the built environment as well. You can get stuck on the complexity of air quality and get stuck on the complexity of the potential factors and confounding factors that might influence an outcome, but ultimately in my world, the built environment world, there's often only so many levers you can pull actually within a home or an office to actually have an outcome. And similarly, I really like what you were saying about policy, that sometimes the reality is that the world is moving so fast we're just not going to know. Ultimately, we can't let perfection be the enemy of the good. Yet at a policy level, we can implement things that can have an outcome.
Simon:A good example of that would be low emission zones in London. We say right, we're pretty sure that traffic pollution, nitrogen dioxide, sulfur dioxide, pms, heavy metals these are having a negative outcome. We can see epidemiological impacts on society. So rather than wait, we start reducing that source and, hey presto, we see an epidemiological impact as a result. So does it really matter? At the end of the day? You identify a source, you. It goes back to basic hierarchies of control elimination, substitution and engineering controls. What are the things we can actually do to protect ourselves from a hazard that's going to be there?
Stephen:Yeah, absolutely. Well, I think, from a regulatory point of view, people have got to try and understand where the issues are so that they can see that if a regulatory factor is introduced whether it's low emission zones or whatever it happens to be and it affects them as people, then they've got to understand, you know, they've got to weigh up in their own minds. Well, you know, why is this affecting me? What effect is it having? And of course, this is part of the problem with air pollution and it's really a reason why I'm still involved in that, after 50 odd years of research into asthma and related diseases is that the public's broader understanding of why air pollution is a problem and why we have to regulate it in the way we're doing is not really good enough at the moment. So everybody, I think, is aware that air pollution is a problem and there's been enough publicity around all of that over time to raise awareness. But I think the big issue is awareness about what and why and I think this is why we have the pushbacks over the low emission zones, for example, or the ultra low emission zone in London is that it inconvenience people and cause them concern because their lifestyles are having to change and they wouldn't fully appreciate the reason why. But also, then you know, there was the possibility that, in the case of traffic diversion, that there were others then that were going to be exposed to all this traffic that previously weren't exposed. So I think you know, fixing some of these problems can have unintended consequences. Interestingly though, you know, with the ultra low emission zone in London, we're beginning to get some really interesting health statistics now, as opposed to just measuring what levels of pollution are, which is what the mayor of London has been following, which have been falling, which is great, but no, in addition to that, we're now looking at hospital admissions, emergency admissions, and also episodes of bronchial asthma admissions, and also episodes of bronchial asthma and even going further back than that, the way the lung grows over time, because one of the effects of air pollution on the developing baby in the uterus, in the pregnant mother, is that it impairs the development of organs like the lung. And, of course, if babies are born with small lungs, then they aren't able to cope with other environmental issues as well as air pollution. So you know, evidence now is emerging for some of these interventions, like the ultra-low emissions app, that these are positive health effects.
Stephen:So all of this takes time, simon, and unfortunately it's not like just switching off a light bulb. Really, all of this takes time, simon, and unfortunately it's not like just switching off a light bulb. Really, when you make an intervention, it takes several years usually before you know that that intervention is actually doing what it said on the tin and affecting the public health. And I think when people realize that it is affecting public health and that their children are going to be fitter as a result of it, then we start to get a reasonably balanced argument going. But of course, getting a public health campaign going is one of the things we're very keen to see now, because the invisibility of all of this and the complexity, as we've been talking about, of all of this sometimes almost defeats people wanting to get involved in it, and yet we know there are wonderful people of all of this sometimes almost defeats people wanting to get involved in it, and yet we know there are wonderful people often the parents of children, as it turns out who are fabulous advocates of wanting to clean up the air. And so I think, as our knowledge base in the science world, which is where I come from increases progressively, as we've talked about, about both from the mechanism point of view and from the public health epidemiological point of view then we're getting to a point now where we actually ought to be going out there and explaining to the broader public in more detail about why this is important and what they can do about it as individuals and why we all have a role to play in cleaning up the air we breathe.
Stephen:And I think we're not quite at that point yet, but I think we're almost getting there. In fact, on June, the 19th this year, I had the privilege of chairing 30-odd scientists who were putting together a Royal College of Physicians report on air pollution and health, and I think the important thing about this report, which had 19 recommendations so it had a lot of things that it said we should be doing, but one of the key ones was that we're moving from thinking of air pollution as an environmental issue to one where it is both a health and an environmental issue, with health obviously taking now a much more prominent role. And as we move into that arena, the health professionals like myself and others who look after the health of the nation in the primary care, in the hospitals, in public health, health of the nation, in the primary care, in the hospitals, in public health, etc. Etc. Start to have a responsibility, I think, for acting as the trusted messengers for this greater understanding of how air pollution affects human health and why we as a community have to do something about it. So I think that's where we're moving into.
Stephen:We're not there yet and I think it's a very exciting period. This really because we're beginning to see in places like the ultra low emissions there in London, but also where they introduce traffic control in Bradford and in Oxford and other places, that there's initial tremendous inconvenience because people don't like change, and you can understand that. But then, a little bit further down the line, people adapt and start to begin to realize the benefits, and one of those benefits is, of course, the gain in human health, which we've been talking about on this discussion. But the other benefit is the improvement in the environment itself and, of course, the reduction in road traffic accidents, for example, the increase in green spaces where children can play and move around more safely, where they can ride to school on their bicycles and not feel they're going to fall off on their bike with vehicles, and so on.
Stephen:The added value of doing these interventions starts to become more apparent, and I think that's a really important bit that we've probably neglected a wee bit really, in terms of the air pollution argument. We've always framed it in terms of air pollution on the environment or air pollution on health, but in fact, if we start beginning to think of where this air pollution is coming from, what we end up with, if we start to replace this with cleaner engineering and cleaner production and industry and cleaner vehicles, what we end up with is a much nicer place for people to live and, at the end of the day, that's why we're on this earth. You want to live in places that are decent and and rewarding to live in, and not in contaminated, dirty places which cause disease. So that, I think, is something I I think we need to probably make a bit more of moving forward yeah, there's a.
Simon:There's a couple of points there. I wanted to pick up on one of them, I think is. You know, one of the things the sustainability movement had to grapple with was selling the co-benefits of sustainability. I think that's one of our challenges in the air quality community is understanding that it isn't just a straight line medical outcome outcome. Actually we can create some nice places to live or better environments or, you know, there are co-benefits to improving air quality as a result of the things that we do to fix emissions. That help everybody wants. You know, I think you know it the the vision that that you have in your mind's eye is a nice place to live often, you know, and that that we don't sell that enough.
Simon:Um, that the question I had is on this medical link and I think it's interesting. Um, the blunt question is is the medical community ready to step up here, because I think it's been largely absent from the air quality thing. And what are the challenges, as you see it, for translating this scientific understanding into clinical practice, into the things that actually matters? Practitioners asking tell me why your environment isn't a good story for the symptoms that I'm seeing in front of me, and developing the workflows to start improving outcomes for people. Is it an unfair accusation to say is the health system ready to start stepping up here?
Stephen:Yeah, very good point, simon, and I would say it is getting ready. I suppose it is ready. So for tobacco smoke in open spaces, all on public places, you know, the medical profession played a really big role in getting new legislation in and that was amazing. And, of course, when we had that, it wasn't the fact that it was the people hadn't the choice to smoke they they did have the choice this month but it was the fact that smoke was damaging other people, um, especially in in pubs and occupational settings where they're exposed involuntarily to to passive tobacco smoke.
Stephen:Well, in a way, we're a bit in that area here with air quality. It's just that I don't think, as came out in the Prevention of Future Deaths report from the tragic case of little Ella Kissy Deborah, the little girl of nine who died of asthma from air pollution back in 2013, in the Coroner's Prevention of Future Deaths report, the fact that the health professionals of the six hospitals in London who managed Ella's tragic attacks of asthma not once was air pollution ever mentioned, either in the outpatients or when she was in hospital, meant that, basically, the health profession itself wasn't aware of the importance of air pollution. So I think that is an important issue that we need to address and that's one of the issues we highlight in our Oral Ecology Physicians Report. I just mentioned that we need to put in a proper program of training in medical students, in other health professionals, and then postgraduate training to make the health professionals aware of the importance of air pollution in helping as a contributing factor in the disease they're managing, whether it's diabetes or dementia or whatever it is. And by making that awareness it's not that you're expecting the doctor or the nurse or the physiotherapist to suddenly do something and to make a massive difference, but what you are expecting is that a highly professional group of people like those I've mentioned can then start to lobby local government in planning procedures, central government to insist that they've got to make the changes to improve the public health and to get a more preventative health program moving in this country rather than treating disease.
Stephen:Because, as our current health minister, health secretary, has been saying all along, you know we have a wonderful public illness service, another public health service, and so what we have to do is create health, and creation of health is about creating a good environment for people to live in and a good diet for people to have, and then behaviors like exercise and active travel, which improves fitness. All of those things together, then, can improve the resilience of human beings not only to air pollution, but to other things like virus infection in the winter months and some of the nasty things that happen in life when we come across other infectious diseases or other stressors. So, you know, I've been talking here very much about air pollution as an issue, but I think it has to be seen as an issue or part of a series of issues, which are about making sure that we, as human beings, are fully informed about what we need to do to improve the chances of us and our children having healthy lives. But then the health professionals being the messengers, in a way, as well as school teachers and public health people and public health people but being the messengers to help the public understand why they have to do these things and why we need to move away from fossil fuel burning, for example, towards alternative energy and so on. And I think the public will understand if we put it in the right frame really, and that's why we do need the health professionals to play a more active role in this.
Stephen:And, as I said earlier, we're just getting to that point now. We're not there yet, but we're getting there and I think when we do get to that point we are going to see a change and and I think that change is going to be in the long term for the benefit of the health of the public, but especially for the generation to come behind us yeah, and I and I think we're in this new era of public knowledge where I think we need a much more nuanced um understanding of how we communicate risk to the public you know, I think grand sweeping black and white campaigns probably aren't going to cut it anymore, and I you know, because I you know, I had a note here.
Simon:You were talking about sustainability again and and one of the things you talk about is this kind of vision zero. You that there's no safe level of air pollution and I wonder if there's a risk there that it falls into the tropes of net zero, where we have these visions. But, as you and I know, there's no such thing as zero risk. We've got to find a way of communicating risk and balance to people in a way that says, look, there are these risks, but it's how you as an individual often, and us as a society, come together to manage that exposure to that risk, and that has to be born out of information and knowledge. I'll get you back to the podcast in just a moment. I'd just like to take a minute to tell you about Zender, one of our partners.
Simon:Zender is one of those companies that, if you're working in indoor air, you've probably come across. They really cover the full spectrum when it comes to ventilation, from simple mechanical extract right through to full climate systems where fresh air is enriched with heating and cooling. They offer the ventilation units, and they also offer everything around it air distribution components, smart controls, the expert advice to make sure systems actually work as designed. One of the things I really like about Zender is their focus on knowledge. Through their experience centres and the Zender Academy, they help professionals keep pace with this fast-changing world of indoor climate, whether it's tackling overheating, improving indoor air in tight retrofits or simply making sure your filters are doing their job. Zender brings experience, depth of knowledge and clarity to the conversation around healthy buildings. So if you're involved in building design, housing or indoor environmental quality, they're really worth checking out.
Simon:Details are in the links in the show notes at airqualitymattersnet, of course, and at Zender. That's Z-E-H-N-D-E-R groupcom. Now back to the podcast. I can't remember the saying now. Our job is to provide unbiased advice, to persuade, not to influence, or something like that. It's this. Yeah, you know well that's good.
Stephen:Yeah, yeah, and you're right. And, and I think with the information world we live in, there's so much information out there. You know, getting access to what's called trusted information is the big issue here, and course, one of the great risks with all of this is that you'll always get those that won't trust the information and rubbish the science in a way which you know upsets me, having spent my whole career in science. When you have people who want to believe themselves rather than believe in what years and years of work have done, I mean, I understand people can hold their own views, but to influence people not to believe in the science, I think is quite terrible really.
Stephen:I genuinely don't know whether I should say these things, but when I read the headlines today about a child dying of measles, you know there is a perfect example when the vaccination drops below 75% and children start dying of a common disease, that's perfectly preventable To me. You know that says it. I mean, what more do you want? And same with air pollution, in a way. You know, how much value do you want to give to a child's life or to a young person developing a disease against a particular piece of enjoyment an individual wants in their lifetime. You have to balance these things and I think we need a just society where the disadvantaged in particular are properly informed so that they can help, I think tilt the balance more in their favor and I think we need to move away I'd love it to move away from the more selfish way of individualism where everybody sort of wants their own slice of the cake and doesn't care about anybody else. I think that is the sort of societal problem that leads to. Some is some of the things we've been seeing around the world recently and and which is kind of troublesome and I had hope with with like tobacco smoking or for some of these other public health issues.
Stephen:You know that by by framing it properly and by putting it in context and getting people to sort of appreciate that they're contributing to a wider activity and there's a lot of reward personally for engaging in those activities, then I hope, as a consequence, progress will be made.
Stephen:And you know, if we go to countries, you know, like Norway or Sweden or other beautiful countries that have not had some of the population explosions and pollution problems that we've had, we appreciate what that means because these are places which we admire. Likewise in our own country. When we see the impact of a really nice environment, um, and then see it all messed up by various things because we've all done our own thing and not thought of others, then you know it's it. We get what we deserve and I I think we're. We're at a bit of a low at the moment in this country and we're trying to kind of fight our way out of it. I think this sort of ability of adopting a positive attitude and contributing in a way that can benefit multiple people, not just oneself. The abolition discussion is part of that journey and little things will make a big difference.
Simon:Yeah, hear, hear to that. And you know, I think one of the things that air pollution definitely is is that it doesn't affect all parts of society equally. There is an inherent unfairness to those that are most exposed to poor environments and I know you've been deeply involved in the case of Ella, but also in Awab and we have to remind ourselves. Behind this are real people and real people's lives and effects on real people's family, and for every Ella and every Awab Ishak, there are countless, countless children and families that may not have been that extreme but nonetheless whose lives are being profoundly impacted by poor environmental conditions, and I think that emotive end of it.
Simon:the storytelling behind this is the thing we need to start pulling out of society better, because I think nothing motivates people in society better than unfairness. I think, generally speaking, society is based on fairness, and if you can expose unfairness, that motivates people, doesn't it?
Stephen:That's what makes the british what they are. You know, and I think in a way that's um touches to the heart of you, know, individuals, existence, and air pollution is only part of it. But on the other hand, you know, as you, as you say, you know, when we have um, the highest level of asthma in the whole of Europe, here in the United Kingdom we have the highest deaths of asthma of the whole of Europe, and by the whole of Europe I don't just mean the European Commission and the European Union, I mean the entire whole of Europe. So we have got ourselves in a state now where here we are with what we say is a national health service with the highest death rate and the highest hospital admission rates for asthma in the whole of this block, and we've got to start asking some questions. It's not about just giving people lots of drugs. We don't want that, goodness me. But since we're talking here about largely an environmental condition, then you know, surely it's the environment we should be concentrating on and getting ourselves fit to be more resilient to diseases like asthma, and that's really, I think, the direction of travel for the future.
Stephen:And, as you very, very correctly point out, there are people living in disadvantaged communities who have no word in this. All they have is the receipt of what others are putting into the air and causing the problems. And I think housing really you know the dreadful state of British housing in some areas, you know absolutely shines a light on this. British housing in some areas, you know, absolutely shines a light on this, with the damp and the mold and the respiratory problems associated with that. So I think you know the time has come now to sort of say look, this is enough.
Stephen:We, as Brits, want to see a fair society and we want to make sure that, you know, people live in decent conditions, whether it's the houses we live in or the roads, or the communities with the roads that it has, or the shopping centers that we have and all the rest of it. And so we have quite a lot of work to do and I will come back again if I may, simon. That's why we need, I think, a public health campaign to get this sort of the benefits side of this put over, not just the. You know this is going to be painful, it's not going to be nice to clean up the air. No, we've got to be able to sort of put positives in and then get people to be part of this wonderful journey we're going to embark on, which is to clean the air for the betterment of all.
Simon:And there are some amazing people in this space. You know, I know you lead a group of clean air champions. We've had Douglas Booker on this show talking about environmental justice, which I know he's very passionate about, and social justice, which you know puts some really powerful points, and many, many more of your colleagues. Why isn't that enough? What do we need to do? Clean air champions have been around now for how many years?
Stephen:five, six, but we've been operating for for just six years what, what, what needs to happen next?
Simon:what does a roadmap look like? Where a public can as we often say on this podcast, we already have the knowledge we need to make a difference to the quality of the air we breathe. This isn't a lack of evidence at this stage. This often isn't a lack of tools actually even to be able to improve housing and ambient air quality and so on. This is about how we share that knowledge. This is about how we communicate it. This is about how we create urgency to sort it out. Why does that? Where's that gap exist in your mind's eye and how do we start to break that down?
Stephen:I think part of the problem is the trade-offs really. So what we have with air pollution obviously the contributors of all of that in large part are the burning of fossil fuels. Let's just put that as a sort of big component at the moment, wherever it's coming from oil, petrol, coal, whatever it is burning of fossil fuel. So why don't people want to sort of change from burning of fossil fuels to a cleaner form of energy? And if we got the net zero achievements that are promised by 2050 with the current government, there'll be a huge improvement in the air we breathe, massive. Many of the things we're pushing for are all about trying to get to those endpoints, but the point is that means people having to change change what they do, change the way they do things, and because we operate in large parts as a society, that's not just an individual changing. It means whole communities changing in the way they do things and the way they wish to do things. And then we're getting into the social science. Now what is it? Or the political and behavioral sciences? What is it that makes a person more able to change what they do than not change? What is it we need to do to try and put the carrot out there rather than the stick, and I think that's what I mean by a public health campaign is that we need to present the broader public and with industry and every part of society, with more of the carrots than the steak. We need to demonstrate the added value and the benefits of cleaning up the air that it would have on society broadly. But we also need to start having some serious conversations about trade-offs, because, after all, it is trade-offs. It is about whether you're going to sell your car and buy another car which is electric or whatever it is, or whether you're going to cycle to work rather than drive your car to work. These are trade-offs. So we've got to try and find the positive trade-offs, which undoubtedly exist out there and are present, and bring them together to show that by doing certain things, things can change.
Stephen:And so having, as you pointed out, stories, examples, public health champions that are not people like me or scientists, necessarily, but out there in the real public, whether it's, you know, mums for Lungs, or whether it's Rosamund Kissyums for lungs, or whether it's, uh, rosamund kissy deborah with her daughter who died away, whoever it happens to be, we need people to rise to the challenge and join an increasing group of people saying the time is now right to clean up uh earth and to create a better place for us to live in. And cleaning up the air is one of those things that will be part of that journey and, and I think, if we get the professionals behind it, so and by that I don't just mean doctors and nurses and physios and medical people I mean professionals in terms of the industry as well, because they they're a part of this so them moving towards a cleaner manufacturing and alternatives will reduce the chemicals going into the air in the first place. All of that, so they need to come on board as well, and the advantages of that in terms of clean growth, or green growth as it's sometimes used, are fairly obvious in this country, where we want to be more independent for our energy supply, not be dependent on gas and coal and oil coming from other countries. So I think there's very good reasons why industry will want to move in that direction, just as the broader public do.
Stephen:And I think the other thing I'm very keen to try and promote is this sort of biodiversity, really. So when we go to places where there's biodiversity and you know the public travel a lot these days around the world. They go to all sorts of different places. They're very aware of this as a subject area, whether it's some parts of Africa where we're losing big game wildlife, or whether it's bacteria in the soil and the diseases we're getting as a result of the change in our diet. Now, right away across the whole of that, the biodiversity is an issue we need to address, and air pollution is a big part of that, and I mean you could even say you know the reason we got COVID-19 in the first place back in 2019, 2020, was because that virus was liberated from the animals it was always in, probably bats and related animals in some parts of China into the human race, and that was because of the pressures on the environment that those animals were living in. So it's the sort of human pressures on that environment that led to that escaping and whatever happened subsequently, and there will be further examples of this going forward.
Stephen:So I think we kind of need to capture these stories. I love your idea of storytelling. I mean, I'm a great believer in storytelling, having spent 50 odd years writing scientific papers because I think, when it comes to explaining things to people, putting it in their terms and putting it as a story, as we've always valued as human beings. Storytelling is a way of transmitting knowledge and information through the generations. Storytelling is a really good way of getting this across and I think we now need to collect these narratives in our communities where we can give examples to others and new storytelling is a way of improving knowledge and getting people empowered and excited and stimulated, uh, on this journey, you know, towards improving the biodiversity and tuning up the air that we breathe in the um breathing environment I think for, particularly for individuals.
Simon:You know, we we, within our own internal monologue. We are always the, the heroes and villains of our own story. You know, we frame our decisions and our behavior based on a, a story we tell ourselves about why we would defer gratification for a better long-term outcome and so on. These kind of things that happen in behavior terms are based around very sophisticated stories that have been built and framed around us since we were born, since the very first books we were read by our parents. It's how we frame our lives and you see that in different parts of the world, where there are different cultures about how those stories are framed, behaviors at a societal level will be influenced by those stories. So we've got to find a way of unlocking those narratives. And you know no disrespect to scientists they are the worst at communicating often really powerful messages in a way that's going to resonate. Um, we've got to get better at that. That there's no we have simon.
Stephen:We have simon and I think you know it should be part of every scientist background training really is knowing how to better communicate better, and I see all of this improving a lot. I mean, it's been wonderful being a clean air champion, with early career researchers having sessions on communications, which is what we've been running these last six years, to get those scientists into a position where they're confident to talk in this way that we're wishing, really in the storytelling line, rather than thinking mathematically or thinking in terms of scientific jargon. And when you see somebody who's good at communication in the science world, one immediately knows what good communication is, because you know they can say a few things in three sentences and people understand, whereas sometimes the scientist has to write a book there to explain what they're doing, and we can lose science for decades.
Simon:I mean, I just finished off reading um airborne by carl zimmer and the wellses, which were very important to understanding infection risk. Um we lost decades of science to the fact that they were absolutely dreadful communicators.
Stephen:Um and yeah, and it, the book was written and it went on the show.
Simon:You know, it's just one of those things I, I think, I, I think it's it. It's interesting this, how we, how we bridge this gap, and I I muse about this myself often and I wonder if it's just because of the nature of the automatic nature of breathing that there's a mental disconnect, somehow, between something that's such a basic instinct you know, it's the last thing that leaves us when we die is the, the taking a breath. It's so fundamental within the human psyche that somehow we don't want to draw those associations that so many of the other things we've had very good public health, um, uh, outcomes from have been habit based. Like smoking, we can create a villain in the piece, we can draw a straight line to it. We've been able to demonstrate that water is another good example of it. But you and I have been speaking here for over an hour and not once has either of us thought about the quality of the air that we've just breathed in, right?
Simon:so we've got a big challenge on our hands, I think, to create an environment where people are aware of the quality of the air that they're breathing in a way that changes habit and culture and behavior.
Stephen:That that that for me and I and I struggle with that, I'll be honest yeah, no, I think we all do, and I can understand it really, because the lung doesn't hurt like any other organ and you can't see things in the lung, as you said it's, it just goes on. Yet we're totally dependent upon it for life and we started this interview. You know about the breathed environment and what's in the air we breathe, and I think this isn't about worrying people and making people sort of wake up in the middle of the night thinking what's going to happen next. But I think it's like everything else, if we can put it in the right context, solving the issue about the breathing environment should be fairly straightforward, to be frank, we shouldn't be trying to introduce things into it and hide them from people, pretending that they aren't there, and then diseases appear several years later and it causes problems. So I think there's a large responsibility here for the national and local governments to take a lead role. I mean, we don't have influence over the quality of the air we breathe on a daily basis, at least to a large degree, apart from tobacco smoking and vaping and those sort of things but in general, we do not have much influence over it.
Stephen:Yes, we can choose to walk in a nice way away from traffic when we go to our workplace or school. And, yes, we can decide that we'll ventilate our homes properly by opening windows and all the rest of it, and all of that's great, but at the end of the day, the actual air quality is a commons, and that commons, I think it needs regulating centrally and by local governments as part of its responsibility. And I would put it very much, as I recently described in our RCP report, at the level of the sort of planners, those that think about our urban settings where people live, our environments, the quality of our housing, the quality of our roads, the quality of our classrooms and schools, the transport and how we get around, whether recycling or running, or whether we have to have tractors dropping people off at the school gate, those sort of things, all of which in their own right are relatively small but when added together would make a massive difference to the air quality we breathe. Things all of which in their own right are relatively small but when added together would make a massive difference to the air quality we breathe. And then, when we add, you know 46% of the pollutants that affect human health and the way I've been talking today also are the climate forces.
Stephen:The chemicals that force climate change and some like black carbon, are up to 100 times more active than carbon dioxide. And, of course, if we got rid of black carbon not the same with cure it you'd overnight deal with some of these health issues. It'll take many, many years with the same equivalent for CO2 to get the climate change and I think these are really hits for the climate folks too. By getting the air cleaner. They would hit their targets far quicker if they were able to get rid of some of these particles and the ozone and some of the volatile organic chemicals, which are climate-forcing chemicals far more active than CO2.
Simon:Yeah, and, as you say, it is the commons and some of this stuff isn't as obvious as other things. You know, I think most people can understand that traffic pollution might be a villain in the piece. But you know, as an example, now in central london, uh, particular matter from commercial kitchens is now the number one source of particular matter. Now, for most of us, what's the most evocative feeling as you walk into the kitchen quarters of central london is the smell of barbecue, smoke and food in the air, and it's evocative of a summer evening walking around london. You know, these are, these are nice mental connections we're making with something.
Simon:So some of these miles are going to be hard miles to rectify and as we remove, one source we're into sources that might, as I always say to people in the built environment, that smell of the bacon sandwich wafting up into the bedrooms in the morning on a Saturday morning is the smell of polyaromatic hydrocarbons. You know, like our association with some of these pollutants aren't always negative, they're often very positive.
Stephen:No, no. But of course, the reasons you can smell as you walk into Chinatown or some of these other parts of London is the fact those that are working in the kitchens will be exposed to very toxic levels. Therefore, why not vent them to the commons outside, where it's not regulated, and get rid of it? And of course, as you say, it diffuses all around the neighborhood. And I think that the personal problems, the things that we do in our lives, like deodorants and sprays in our homes and the lacquers and paints that we decorate our houses with, these all contain chemicals which are pollutants, which are contributing to the air pollution. And I think again, if we make industry and the public aware of these things to a greater extent, then alternatives can be found. And I think that is really what we're talking about here is not getting rid of things necessarily, but actually, as you said earlier on in our chat, replacing things with more sustainable ways of doing things.
Stephen:And if you look at cooking, it's quite interesting.
Stephen:You know the way the UK, I suppose, population is moving away from heavy meat eating, you know, towards vegetarian diets and nature-based sort of eating more.
Stephen:You know. That isn't an accident. I mean that's because campaigns have been done to change behavior one way or another, and the environment just has a big role to play in that argument, not the total role, but quite a big role. And you know, I can't go into a meeting in the Department of Health, for example, without having a vegetarian meal, because meat isn't served at all at any of the missions, because, you know, even the Department of Health and Social Care have taken this on as a full-time task. So you know, these things can happen, uh, if we actually, uh, you know, are keen to see them happen, and we probably and we frame things in the right way. And I think this whole discussion a very pleasant discussion with you, simon today is about really framing the debate in a way that the public can find more acceptable, can understand what the processes are and then want to be able to contribute to it as individuals as well as the broader community.
Simon:How did you find yourself here, stephen, being such a central advocate in the UK for clean air? As a clinician, first and foremost, and a scientist, has this been a long journey You've walked to find yourself doing what you do today.
Stephen:Well, it has really, because I started my career as a clinician and then went into research and spent a few years in boston in america and came back to britain to set up a new research laboratory in in the place I live in now, southampton, which was a new medical school at the time, and those are very exciting days and you know, I spent 40 or 50 years doing that and improving the management of the disease I became interested in, which was asthma.
Stephen:But then when I read about cases like alakazadebra, as you mentioned, you know, and the fact that I'd worked in the area of research to try and find what are the drivers of asthma and air pollution clearly with one of them, just as viruses and allergen exposure are other environmental causes Then we set up ways in Southampton to be able to measure the effects of these. And once you start doing that you begin to realize that this is an important area and then gradually I became more and more interested in it. I was the chair of the first government advisory committee on air pollution back in the mid-1990s when this was just beginning to get going and of course, having every so often, I suppose, boost of all pricking of one's conscience by cases like Ella Kisidebra and the little boy in Rochester you mentioned Ashok. When we have those, it just makes us realize that we have a really important job to do here in not only doing the science but getting that science to work for us and then to work for the community and what it's actually saying.
Simon:There's no point in doing the science if it's not actually going to have an impact, and the impact in terms of air quality is on public health and some really, really um, emotive and personal touch points for you as a scientist and as a researcher that this stuff has direct line impacts to both individuals but society as well. You know that because I always, I always, I always um feel sorry for not sorry, but I wonder there are. There is research you can do where you're stuck in a back room of labs for decades and you don't really see the coalface of the impacts that you're having. Or it's so many chains removed that by the time it has an impact it's very difficult to feel it. But this stuff I mean you've been personally pulled into and advocated for real people whose lives have been impacted in real ways by this.
Stephen:No, it's nice of you to say so. I mean, I think part of this really is the fact that all people who do research want to feel that whatever they're doing, wherever it is, it makes a difference. You know, that's what they want to do, that's why they do it. I mean, the way they do it and the fields they go into, you know, is a whole different story, but the basic underpinning principle is that they want to make a difference and then, and as a consequence of that difference, improve usually not always, but usually improve the lives of those around them, whether it's industry, whether it's health, whether it's whatever. Um, so that's really why people do it, and I've been very fortunate to be given these opportunities really to be able to come up, you know, and actually see some of these issues face-to-face.
Stephen:And when you do that, the raw reality translates itself into a sense of desire and action, which is what I hope I've been able to do over the years Still not done I have to say, simon, but I think the pleasure it gives me to see all these amazing people doing all this research and their research now getting used to help bolster the movement towards cleaner air is very, very encouraging and that's why I'm a Clean Air Champion these last six years is to try and put the glue between the joints of the different research and to get the researchers themselves to promote their own activity to a broader environment out there of public and business and policymakers so that their research does in fact make a difference.
Simon:Yeah, and that's absolutely key, and one of the things we'll definitely do is share the Clean Air Champions website in the show notes as part of this. One of the things I was keen to talk to you about because we have spoken about it before and, talking of research, it's been one of the things that you spent quite a lot of time looking at is this this barrier function, the immune response of air pollution, particularly how it influences things like asthma, is. Can you give us the the 101 on that? What, what you mean?
Simon:yeah, the kind of the elevator pitch for what are we talking about? What is it about?
Stephen:air pollution and this barrier function of the human body and how ultimately impacts things like asthma well, of course you know, our bodies are very complex systems and this whole story we've been illuminating in this conversation has illustrated that. But the bits of our body that face the external world, whether it be the surface of our eyes, our nose, our lungs, our skin, our gut, our bladder, all of that has to develop protective mechanisms about what the world introduces to those particular parts of the human body. So, in a way, over millions of years, our lining cells, if I could be very crude, our lining cells of these various tissues and organs, whether it be the skin, the lung, the gut, our lining cells have developed in a way where they can filter the good things and pass those into the bloodstream, where we can make use of them, but stop the bad things from entering either the air or what we eat or what we touch, stop the bad things from getting into the circulation. But the problem is that things have changed so much is that that subtlety is breaking down now and the barrier, which obviously was very effective at one time in our evolution, is no longer serving its function as a barrier, as it should do and therefore things are getting through. And we know that, for example, in contact dermatitis, which is an allergy of the skin.
Stephen:When one touches certain chemical substances, some people become very sensitized and their skin develops a very itchy rash, and that's because the barrier has been broached and the immune response recognizes that chemical as foreign and, as a consequence, mounts this allergic response against it. So, in a way, that's what bronchial asthma is is that the barrier is broken down to some of the environmental factors, whether they be viruses, whether they be allergens or allergicgens or whether they be chemicals that are in pollutants, and, as a consequence, the body mounts an immune response to it. And that immune response would normally serve as a sort of protective response, as against parasites, where the same immune response against parasites occurs against parasites, occurs in allergic disease. But in allergic disease it's not directed to the parasite to get rid of it, it's directed to the protein or the chemical in the allergen which causes the allergic response to occur and asthma a large part of it, at least 80% of asthma, particularly that's in childhood that goes into adulthood is allergic in nature and due to the fact that these allergens and chemicals have breached the epithelial lining cells of the lung and got in to evoke this inflammatory and allergic reaction. So that basically is it.
Stephen:And what we're trying to do now in research really is obviously find ways of strengthening the barrier. That would be great and various research people are working in that area to make the barrier tougher so that we can actually resist some of these things getting into the body. But the second is to make the resilience greater, that is, to get our bodies, our immune system, to be able to tackle these agents and to suppress them without causing the inflammation and the allergy that I've just been talking about. And that process is now taking place in some very active research. And just picking up the newspaper today, you know, I just read an article about the future of cancer research, about, you know, augmenting the immune response to be able to fight the cancer cells. And remember, the cancer cells are there largely because of the environment, whether it's diet or breed or chemical cancer forms because of environmental insults in large part. Then if we can evoke an immune response that's going to neutralize cancer cells, then we get rid of the cancer and we've had some spectacular success in the last few years along that route.
Stephen:And Stephen Parris, the medical director of National Health Service England, you know, is saying that he thinks that's the future. Well, I would say that's the future of diseases like asthma. If we can not just treat asthma by suppressing the process once it's started, by giving inhalers in one form or another, but rather, maybe in childhood, augmenting the ability of the child not to become allergic in the first place and preventing the allergic response to houseless mite, to mold, to grass pollen, to pet proteins, if we can prevent all of that from happening, then asthma won't develop. So that's really what we mean by barrier function. That's why the research at this interface between the internal organs of the body and the surface organs, which I'm talking about now, is so important in terms of coming up with new ways of preventing disease, because that has to be the future prevention Prevention not necessarily just treatment.
Simon:It sounds like a fascinating area of research. I guess this is where we start to come into terms like the total exposome as well, where we're starting to try and because it's a bit of a trope, isn't it, that we kids are exposed to too much. Kids aren't exposed to enough that you know the you know so, on and so forth, aren't exposed to enough that that you know the, the you know, so, on and so forth. And this is ultimately about a balancing act around the environmental potential, environmental insults whether they're there by nature or they're by something else and our body's response to them. Do we? Are we exposed to enough of them? Not, enough of them. Is the reaction by the body the right reaction or an abnormal reaction in some way?
Simon:And there, in a nutshell, is a lot of asthma. You know it's that. It's that what triggered it? Was that something that we could prevent? Or is it just a natural part that some kids will be triggered and eventually create an immune response that causes asthma? And then are there allergic exposures to things that exacerbate that over the course of their life. You know, this thing's a really complex mix, isn't it? And in that complexity is a lot of uncertainty for people as well is a lot of uncertainty for people as well, and you only have to think of things like IBS and dietary inflammatory responses to things. Or we're hearing a lot more now around generalized inflammatory disorders as a result of mold or mold VOCs or exposure to certain pollutants. All of those things can be true, but I guess in the clinical world they're really complex things to untangle and we've got to be really careful not to associate every response to something that this is a really difficult thing to try and navigate our way through I think you described it beautifully.
Stephen:Actually, that's exactly, uh, the challenge we've all got at the moment. There's some wonderful examples that are out there in nature. So if we, if we go to north america, for example, there are some Central Europeans who moved over there in the mid to late 1500s when the religious pressures made the move away from Central Europe to North America and different communities set up there, and some of these communities maintain the traditional lifestyle the Amish people, for example, in Lancaster County in North America, in Pennsylvania. And then there are others who came from the same community but went to other parts of North America and set up their own communities but actually took on modern farming methods and modern ways of driving vehicles and all the rest of it. So here we have, on the left, the Amish people who were still going around in horses and carts and had a natural kind of lifestyle, with no tobacco smoking, no chemicals, a diet that was very much based on things they grow locally and all the rest of it. And then another group of genetically absolutely identical or nearly identical individuals who have taken on a Western lifestyle. An allergy and asthma in the Amish does not exist at all zero, whereas in the Hutterites who are genetically the same they've got about 25% are allergic to the environmentalism you and I understand. So the only thing that's different in those two populations can't be the genes, because they came from the same stock, so it has to be the environment and the, you know, anthroposophic sort of traditional diet and lifestyle and all the rest of it of the Amish. You know it's protected them, as it has done, against coronary heart disease, mental health issues and a number of other rheumatoid arthritis and a number of other conditions. And surely there's something that says something about what's happened in the intervening 300 years where we've taken on this Western lifestyle.
Stephen:We can go to China You've got an almost identical story over there where the rural Chinese there's hardly any astrology at all, but as soon as they move to Beijing or Shanghai or Hong Kong, the next generation of kids that are brought up from those families are all highly allergic. And the difference between them is the fact that the lifestyles have changed. And if you wanted to really cut down to the basic, what is it about the lifestyle? Well, obviously it's the diet, because they're largely vegetarian, but also the fact that their livestock are living in their houses in large part. So in the case of the Amish, they've got the cow sheds and the other animals living adjacent to the houses and share that living accommodation, almost so they're breathing in whatever those animals are generating the fungi, the bacteria, the other things that we just talked about and to go out to the wilds of china, and it's the same.
Stephen:But there is chickens and and various, um, you know, other animals not cows that are living in close to the homes and these babies are from and the pregnant mothers are being brought up with exposure to all of this. So their exposome, which is the word we've used a few minutes ago, is very different in terms of what they've been exposed to, compared to what an urban child would be exposed to. And then, when they look at the bacteria in the gut or in the lung, which is a consequence of these different exposures over, you know, 20 years or so, they see an entirely different set of microorganisms that have taken root in the gut and in the lung because they've been exposed to different ones in the first place, and these will have been the protective microorganisms that are developing the chemicals that protect them against becoming allergic. And those are the things we've lost in our rush towards urban development and doing things quicker, faster for more money.
Simon:Do we know, or is that your gut Like, what are we…? No, that's a fact.
Stephen:Yeah, yeah.
Stephen:So those are facts, and I think you know, I think just trying to turn this into something practical.
Stephen:Obviously we can't go back to living in 1500 lifestyle in terms of diet and farming practice, but what we can do is try to find out what are the microorganisms that these people were exposed to and it's not just simple lactobacilli and various things and drinks that people have these days. It's more complicated than that, but identifying what it is so that we might be able to develop a vaccine to give to a child as part of the vaccination strategy, or something that they can eat in the first few months of life to colonize their bacteria, their guts, such that they are then protected going forward and can build up the resilience that we're lacking at the moment. I mean, that's just an idea, but I mean it means that I think, by understanding how nature has been subversed and how nature's impact on maintaining health has been broken down by our rush towards industrialization, then we might actually find a way, or more than one way, of putting that back into the system and therefore giving children the protection they deserve.
Simon:Yeah, I've had this conversation before. It was a question actually. I asked Hector Altamira from UCL. We often talk about our exposure to damp and mold, say, in housing. Um, yeah, but one of the things we haven't defined is what a good level of exposure is that? Because I think everybody instinctively understands at some level a totally um, antibiotic and virus and bacteria-free environment isn't good for anybody. So at some level there's a point, there's a line somewhere where the microbiome is, on balance, healthy or providing a rounded Well, that's what we need.
Stephen:Simon. So if you're talking about future research and epidemiology, that's what we need to do now is exactly that is, to build up a portfolio of lifestyles and exposures across the United Kingdom, if you want, from you know, disadvantaged urban environments right the way through to advant advantage rural environments or rural environments, people living on farms and just build up over tens of thousands of people, not just 10 or 20 people, tens of thousands of people, what that relationship looks like, because only then can we be certain. What should we be trying to achieve? And that experiment is not different from the air pollution experiments we're doing now, where we're measuring air pollution exposures to 60 million people and looking at the health consequences, where the confidence intervals are so small that there is no error any longer, whereas we need those sort of experiments I've done in the way you just described it, in the respiratory microbiome, in the gut microbiome across these different sectors of society, and then to follow, using electronic case records, what their clinical expression of disease is, which will be all on the data because it's collected, and be able to then talk about how the environment is shaping, either to a bad direction or towards a good direction, the emergence of these diseases.
Stephen:So there's the new epidemiology, and I think it would be amazing if we could do that Now. To do that, you need interdisciplinary science and all the research councils to be working together, because this is truly interdisciplinary research If you want to investigate farming lifestyles, versus one who's working in central London. So I think it's a very, very interesting idea and one that I'm trying to encourage. Um well, I won't tell you more about it now, but we are trying to encourage such, such uh a study to be set up in this country to to get that done yeah, and it's one of the areas that gives me a little bit of pause for concern.
Simon:That, and don't get me wrong, you know generally speaking in the area that I focus on, which is the built environment. Generally, we woefully ventilate our built environment. You know to the point that it's almost a joke but the risk is is we throw engineering power at a problem we don't fully?
Stephen:understand.
Simon:It's nuanced, and a good example of that is that, you know, as a result of the COVID pandemic, countries like America under standards 241 have started to develop what they call equivalent air change rates, and the idea behind this is that you can throw technology at an air quality problem to eliminate the known problems like viruses or VOCs or something in a space. So we see that with UVC, with gas phase air cleaners, with a whole range of technologies, and the reason it makes me a little nervous is is that I don't know, we haven't determined what good looks like yet and like the risk is, is we?
Simon:throw all of this engineering compute a bit like ai. These days, we throw so much human power at it that there's some unintended consequences we haven't thought through yet. And and when we look at the most healthy in society, they are not living in those environments. They're living amongst, like you say, the cows and chickens and, you know, notwithstanding the classic public health things we needed to fix, like sanitation and other problems, right, what differences do you see between the 2016 report and the 2025 report? What have been the kind of significant advances between those two reports, and what should people be looking out for in the latest report? Do you think?
Stephen:Well, thank you. So quite a few changes really, because the published literature in the intervening years, the scientific literature, has improved immeasurably, so we had a lot more scientific data to be able to analyze, to build into the report. So the highlights, I think, really are a further emphasis on the systemic exposure, which is what we've just been talking about earlier on, and in particular the role of air pollution on the brain and on child development in the uterus and beyond once the child is born. So those two areas in particular are where we've got a lot of new science and of course they're the two vulnerable ends of life in a way. So that then brings us to the second big area, which is vulnerability and inequity and inequalities, which is the game we touched on and we've got a lot on that in the report about first of all identifying it what communities and then potentially what can be done about it, which I think is quite important health professionals and the broader ability of the public at large to know what they're exposed to locally in the environments they're living in. So in a way you could put that sort of awareness type aspect. And then I think, finally, we've come up with new ways of thinking about policy and policy development, both in terms of the local policy, which is very important because local air quality sits in local policy, but also, of course, central policy, and, rather than having rigid air quality limit values, thinking of new ways of driving down air pollution progressively and measuring its consequences, as we do that I'm measuring those consequences not only just in terms of air pollution but in terms of some of the other benefits that we talked about too.
Stephen:So those are the main points. There are other issues as well which I wish I could go into, but I think they're the four main things that are different and they all really are, I think affect the kind of translation of the scientific understanding of the impact of air pollution to action and that ability to talk now in a joined upup, proper way and to bring together different communities so that we can actually end up with this, I hope, tnr campaign, which obviously TNR, and health campaign, which is something we're going to push hard for, because I think without getting more information out to the public in a palatable way and getting the broader aspects of society to understand the nature of some of these issues, we're going to go nowhere quickly.
Simon:No, I quite agree, and look anything we can do on the podcast to help, support and promote that, thank you, we will, of course uh, we'll put links to all of it in the show notes.
Simon:Um, and it's well worth following both steven and his colleagues in the the clean air champions cohort because there's some really fantastic stuff being done in within the regions of the uk northern ireland really really good indeed. Steven, thanks so much for bearing with us on a stormy Irish, slightly dodgy internet connection day. By the seams of things, it's been an absolute privilege talking to you, as always. Really enjoy our time together. I can't thank you enough for spending time talking to us on the podcast for an hour or so. Thanks a million, thank you.
Stephen:Simon. It's been an absolute personal pleasure for me as well on this bright and sunny day here in England. So good luck with the thunderstorms. Another aspect I think of climate change.
Simon:Indeed. Thanks a million. Bye-bye. Thanks for listening. Hold on a minute Before you go and shoot off or onto the next podcast. Can I just grab your attention for one minute? Off or onto the next podcast? Can I just grab your attention for one minute? If you enjoyed this episode and know someone else you think might be interested in this subject or you think should hear the conversation, please do share it and let's keep building this amazing community. And this podcast would not be possible without the sponsors, ako, errico, ultra Protect Imbiote, aeco, ereco, ultra Protect Imbiote, 21 Degrees Farmwood and Eurovent. They're not here by accident. They care deeply about the subject too, and your support of them helps them support this show and keep it on the road. Please do check them out in the links under their qualitymattersnet. Also check out the show on YouTube with video versions of the podcast and more. See you next week.
