Feb. 20, 2023

Clean Air Is An Inside Job

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Imagine you’re in a sci-fi movie. The one where everything’s on the line.

And while dinosaurs or aliens or a virus takes over down on the ground, you’re the scientist unexpectedly riding in the helicopter with the actual president, the scientist who’s run the calculations and asked the questions nobody else thought to ask, who’s uncovered the virus’s single weakness.

But nobody’s listening to you. Because it’s complicated when everything is on the line. But you know that what you know could save millions of lives.

What do you do next?

That’s today’s big question, and my guest is Dr. Linsey Marr.

A renowned scientist and multidisciplinary engineer who pioneered research into a better understanding of the flu’s airborne status, and how humidity plays a role in the flu’s seasonality. She is among a very small group of scientists who truly understand the aerosol transmission of bacteria and viruses.

Three years later, we’re still wrestling with the implications of this virus and how we level the playing field by cleaning up our indoor air.

And nobody understands the challenges we face – andthe opportunities in front of our faces, literally under and inside of our noses– like she does.


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Quinn: [00:00:00]Imagine you are in a sci-fi movie, the one where everything's on the line, and while dinosaurs or aliens or a virus or all three take over down on the ground, you are the scientist unexpectedly riding in the helicopter with the actual president, the scientist who's run the calculations on your laptop, on your lap, and ask the questions nobody else thought to ask. Who's uncovered the dinosaur virus's single weakness, but no one's listening to you because it's complicated to be the president when everything is on the line, but you know that what you know could save millions of lives. What do you do next? 

That's today's big question, and my guest is Dr. Linsey Marr. 

On March 5th, 2020, long before most of us left the office or pulled our kids out of school, Dr. Marr posted a Twitter thread that said,[00:01:00]let's talk about airborne transmission of Sars COV2 and other viruses. A discussion is needed to improve accuracy and reduce fear associated with the term.

Welcome to Important, Not Important. My name is Quinn Emmitt, and this is science for people who give a shit. In our weekly conversations, I take a deep dive with an incredible human who's working on the front lines of the future to build a radically better today and tomorrow for everyone. Along the way, we'll discover tips, strategies, and stories you can use to get involved to become more effective for yourself, your family, your city, your company, and our world. 

Dr. Marr is one of those incredible humans. She's a renowned scientist and multidisciplinary engineer who pioneered research into a better understanding of the flu's airborne status and how humidity plays a role in seasonality. She's among a very small group of scientists who truly understand the aerosol transmission of bacteria and[00:02:00]viruses.

Three years later, we're still wrestling with the implications of this virus and how we level the playing field by cleaning up our indoor air, and nobody understands the challenges we face and the opportunities in front of our faces, literally under and inside of our noses, like Dr. Marr does. 

Dr. Marr, welcome to the show.

Linsey Marr:Thank you so much for having me. I'm excited to be here. 

Quinn:Well, hopefully it'll stay that way. We'll see how we do here. Dr. Marr, we'd like to ask one question to kind of get things going, and instead of what is your entire life story, I like to ask, why are you vital to the survival of the species and its pretty ridiculous, but I end up getting some actually fairly thoughtful answers out of folks, especially someone like yourself. 

Linsey Marr:Yeah. I didn't really think of myself as vital to survival of the species until 2020 rolled around and the coronavirus emerged. Western medical officials and public health officials were saying, oh, you know, watch[00:03:00]out.

Don't stay, stay outside of six feet of people. It can only be transmitted by these large, visible droplets that somebody coughs out. Sprays into someone's eyes, nose, or mouth. And if you stay beyond six feet, you're fine. Doesn't travel that far. So I knew this was dead wrong because we had studied flu transmission for quite a while and knew that the current traditional understanding of flu transmission was also incorrect, likely to be incorrect about droplets.

And so now we have this new virus and it was like people were being told the wrong thing about how to protect themselves and there was not a proper understanding of how it was transmitting. You know, my group and collaborators, students, and post-docs, everyone I've worked with, although frankly there are probably not that many people in the world, fewer than 10 ish or so who really understood how this was transmitted early on.

So that's what we brought to the table. And I recognize, you know, there are articles in the New York Times, but in the CDC[00:04:00]talking about this idea virus doesn't travel more than six feet. But I was like, oh yes, it, it probably does. And the way we've been thinking about transmission is really not consistent with physics.

And so I started being more vocal about this because I knew that the existing thought was wrong and the information, the right information really needed to get out there quickly. That is why I would say I, I'm vital to the survival of the human species. 

Quinn:Look, it's a legacy question I've kept on for a while and we've just got some great stuff from it.

Now, I will say, and I know you were one of the very early, again, among the 10 or so folks that seem to really grasp the mechanics of, of how this was working its way through us. I don't think we need to revisit all of that. I'm curious for a few reasons. Mostly, well, I guess it's half and half. One half is that my wife is a, a very talented and successful screenwriter and I watch a lot of sci-fi movies and so there's always the doctor that no one is listening to.

So I'm sorry and you're welcome.[00:05:00]But on the other hand again, because our whole shtick here, is again, action oriented and we've got students that listen, senators, scientists, farmers, you name it. It's folks, as we say, it's science for people who give a shit. There's a lot of folks that are seeking to do the right thing in whatever their job is, marketing, uh, who can know.

So I am curious when you are like, I am as confident as I can be in the mechanics of how this seems to be working. And it, I know it was very early when in this whole shtick when you did this. What was your first outlet for trying to address that? Where was the first place you went when you said, I've gotta try to change the minds here.

Linsey Marr:It was Twitter. I had a small Twitter following at that point, maybe a thousand people, mainly people in the air quality community. But I remember posting in the end of January of 2020, in response to an article in The New York Times where they said, oh, you know, six key things about how bad this pandemic's gonna get.

One of those things was, oh, how far does the virus travel? And it[00:06:00]said, and they had a graphic, oh, the virus doesn't travel more than six feet, unlike measles and other, some other things that travel hundreds of feet. And so I tweeted about this and I said, I'm not sure why people think this. Basically saying this is wrong.

That was it. And then in March, my colleague approached me, a colleague recognized what was going on. He's an expert on kind of indoor air quality. Approached me to write a commentary for medical journals and so we did. We submitted that in March. It got rejected by a series of medical journals and then eventually got published, but at that point also in March, there was a professor, Lidia Morawska in Australia who was leading an international group to try to discuss this with the World Health Organization and really try to show them that the existing traditional understanding was wrong. You know, nobody listens cuz and I was used to this cuz I'd been taught studying this for a while. You said that there's that one doctor who nobody listens to. Well see, I'm not even considered a doctor like this is a[00:07:00]medical question, right? And I'm an environmental engineer.

I don't think MDs know that people like me exist. And even if they do, a lot of them don't recognize the expertise that someone like me can bring about how viruses, which are basically small particles, how they move around in the environment, which is kind of what environmental engineers and aerosol scientists do.

We study particles in the air. A virus is just another type of particle to me. 

Quinn:Sure. That's such a fascinating framing to me because we have not unexpectedly made this thing so political and much more complicated than it needs to be. But on the other hand, and I, I do want to get into this at one point because I'm a liberal arts major, right?

This whole thing started, cuz I'm not a scientist or doctor, but I can ask some questions and I can consider the intersection of really having to think about, okay, how, how do we message this thing to people if we're confident in it? Or how do we correct course if we need to? Which obviously we needed to cuz we were[00:08:00]doing it live.

But that does require thinking about not only, okay, what is the environmental engineering, you know, mechanics behind how air works, no matter what the particle is to the sociology and behavioral psychology and behavioral economics of how people take in information or communicate it to each other, especially in the world of Facebook and things like that.

All of that said, and, and I want to get into those particulars. I'm curious if and where you feel like maybe since, let's say March, 2020, I think March 13th, something like that, when I yanked my kids outta school, where have we made any progress on indoor air quality? Both, either actually practically in the real world, in public schools with all that money that was available or whatever, or just in our basic understanding of, as I've called it in, in my writing, you know, needing to level the playing field essentially with this air.

Where do you feel like we've made a step up, if at all? 

Linsey Marr:I think we've made a huge amount of progress in the past couple years. Like progress that I[00:09:00]was thinking would take decades to achieve, and so the pandemic really accelerated that. So indoor air as a research field was kind of the, I don't wanna say the black sheep, but just like the kind of ignored, poor stepsister compared to outdoor air quality and atmospheric chemistry.

That's like the big guns and the kind of more, there's more money in that field and more attention given to that. But you know, we spend 90% of our time indoors as many people have heard now, and we're breathing that air. If you don't think about it that much or until the pandemic, we didn't really think about it that much, but it turns out that, you know, what we're breathing has profound impacts on our health, our productivity, our academic performance, and our, our wellness.

And you know, the pandemic has made that clear. So I think there's a lot more awareness about indoor air quality and the importance of ventilation and filtration. Better ventilation and filtration have been introduced into some public spaces, some schools, so a huge change that didn't happen before. There's[00:10:00]discussion now at local, state and federal government levels about providing guidelines and maybe even kind of standards for indoor air, which again is something that I've thought would take decades to get to.

Quinn:Thank you for that. Um, it's always nice to hear a little like, no, we, we are getting there and a lot of these things were pulled forward, which is, I mean, obviously we had to go through hell to get there, but that's what makes us move, unfortunately. But do you feel a sense of frustration at all that we aren't doing enough.

Knowing what we know now, whether it's on a school or school district or office level or state, local, federal level. When you're like, look, we're three years in. We have all this information. It's not just this, just cuz someone at the school has the flu, like, doesn't mean everyone has to get it. We know what we're doing.

Linsey Marr:I'm frustrated, I guess as a scientist, and that was true. You know, I've studied both indoor and outdoor air, and with outdoor air it's very clear what we need to do. We need to, you know, reduce our emissions of various pollutants. And with indoor air, it's very clear[00:11:00]what we can do, which is improve ventilation, filtration, kind of cleaning the air, like we clean the water before we drink it, but as a person, you know, I recognize that there are so many barriers to actually implementing these changes, which are economic, social, political. So yeah, you know, I would like to see that happen faster and you know, I know what could be done, but I also recognize that we live in a society where, in a democracy where things are, you know, it's slow to make these changes.

Quinn:It's interesting, so I, like I was telling you, I'm above a candy shop in Colonial Williamsburg here, but I just spent, oh God, 15 years in Los Angeles, something like that. And about six, seven years ago, I don't know time, I've lost track of time at this point. There is a massive, massive methane leak.

Alito Ranch, I believe it was called. 

Linsey Marr:Yeah, I talked about that in my class. 

Quinn:Perfect. So what was super interesting, being there for that. And that was[00:12:00]before I had any idea about any, any of this stuff was you couldn't see it. And that was really interesting because for all the pollution in Los Angeles, that's gone up and down, whenever we have wildfire smoke, you can see it, you can feel it, you can taste it whether you are inside or outside.

I mean, we have all out there experienced that now, and a lot of people on the east coast have experienced that now too. Like you said, outdoor air pollution is the big, the big thing. But it was interesting how much, for as catastrophic as it was to air quality and, and emissions, even if they're short term, they're much more intense cuz it's, it's methane how much less people were aware or gave a shit cuz they just couldn't see it.

And I was telling someone much younger than I am the other day about, I was in college when New York State stopped smoking in bars and restaurants. So I remember the fine line between that, that first year and then the next year being like, oh my God, my clothes don't smell as terrible. I can see people across the bar.

My asthma doesn't feel terrible. It seems to really matter, which, I guess it makes sense, what we can see in[00:13:00]water or in air and what we can taste and what we can feel. And like you said, this virus is deadly or, and we have all these other ones, but we really can't see that. And I wonder how much you think that has slowed some of the action we've taken and that people are just going back to school and going back to the office and they don't know how much their air is filtered.

Linsey Marr:Yeah, absolutely. I think that's a huge part of it, and I think that also contributed to our kind of misunderstanding about the transmission of viruses and other pathogens through the air. We can see these large droplets that, you know, if someone coughs or sneezes or talks, and we see those, we understand that those might be contaminated with viruses or bacteria.

But the thing is that for every one of those that we release, there are hundreds of tiny particles that we can't see, and you need specialized instrumentation in order to, to see those or count them and know how big they are. We're a strongly visual creatures and we can't see it. And so one of my dreams[00:14:00]has been that eventually when we all have our VR glasses that we're walking around in, projected onto that screen is like pictures of all the, the pathogens that are in the air.

So you would see it like coming out of, you know, someone's infected, you see them walking along, you see it coming outta their mouth and you see 'em drifting around. And if you could see those, then you might like take a different path or you know, you see them like building up in the room might get out of that room or put on your mask.

So, absolutely yeah, that's my dream. The VR glasses, that'll allow us to see the pathogens around in the air around us. I think that would be a game changer.  

Quinn:When I was in Los Angeles, the hospital system I went to, and which was very good to my wife and I when we had our kids and, and they were wonderful at Cedar Sinai, among the biggest and, and best in the country.

There's this legend, and I'm sure I'm getting this wrong or it's only half true that years ago they were trying to get more people to just sort of stop and wash their hands, right? Doctors, nurses, whatever it might be. I guess the legend was that doctors kind of kept blowing it off in some[00:15:00]way or as much, and someone.

I guess they did a, uh, what is it when you, when you like put a sample on a slide anyway, someone made like a sample of like hand bacteria and put it on a screensaver on some of the computers. So that people could just see this is what you're carrying around. You might feel like you're clean, but you're also operating on people and you're with a bunch of people who are immunocompromised.

Like it matters to be able to visualize that stuff. 

Linsey Marr:Yeah, absolutely. That's why I want the magic glasses. 

Quinn:I'm here for the magic glasses. If I could use that to show my children how to pick up their room, which I can see the things on the floor, but apparently they cannot.

Linsey Marr:Yeah. It's amazing how kids are like that.

Quinn:It's very strange. Doesn't make any sense. I'm sure I was not like that. On that note, we're not gonna have those magic glasses for a little bit. What would you say, again, as an environmental engineer? Am I getting that sort of category correct?

Linsey Marr:Yeah. I'm hard to categorize. If I had to be categorized, I guess that would be – 

Quinn:I'm not trying to put you in a box.

Linsey Marr:That's fine. I mean, I'm, I'm kind of, you have done a lot of interdisciplinary research and that's[00:16:00]kind of how I became one of the few people who, who kind of specializes in this area, kind of bridging medicine and aerosol science and engineering. But yeah, go ahead. Call me an environmental engineer.

Quinn:Let's call you the oracle. So as the oracle of air quality, obviously there's a thousand different versions, if not more of these situations and setups if there are any, but what would you say, let's, let's go to like lowest common denominator. What would be sort of your, from an engineering standpoint, mechanical standpoint, your lowest common denominator prescription for how a school or office should improve their air cleaning or circulation or both? What are sort of the basic tenants of things that you can, probably need to do for your place. 

Linsey Marr:Yeah. One would be to remove the sources. So there's a colleagues of mine talk about some old book that talks about, well, you know, if there's a pile of poop in your room and it smells, what do you do?

You[00:17:00]remove the poop. Okay. Right. So you remove those sources, that's the first thing. And fires, of course, cooking, it gives off lots of stuff. Of course, we have to do that, but if it doesn't need to be there, you can remove that. And then the second thing would be to ensure that our air is not stale.

So you want to kind of be changing over that air, bringing in cleaner outdoor air, presuming there's not wildfires going on, and you're not in some terribly polluted city. Bring in that outdoor air, replace some of that kind of stale indoor air, and you can also filter the air to remove the particles. So those are the things we can do now as kind of a people going around.

I think one thing that would help us see these things is if we go into a room, maybe there's a thermometer on the wall so we know what the temperature is. Well, we could also have a kind of carbon dioxide sensor. On the wall like this, which tells you – 

Quinn:I have like five of those. 

Linsey Marr:Great. Okay, so this tells you, kind of gives you an indication of ventilation.

A lower number kind of is better[00:18:00]cuz if it's higher, that means that there's lots of people's exhaled breath that's building up in the air and it's not being removed. You could have a high number on this CO2 monitor and have low particle concentrations. If you have filtrations, you might also wanna have some kind of particle indicator that tells you about the amount of particles in the air, and that's not just virus particles.

That would be total all types of particles. And those are really important because we know that the World Health Organization estimates that people breathing in particles and indoor or outdoor air is responsible for seven to eight million premature deaths per year. And we know it's linked to things like academic performance and absenteeism from school and work and productivity.

Quinn:Well, and that's what is so compelling and I guess frustrating to me on the trying to level the playing field here of us against these viruses and bacteria or wildfire smoke, whatever it may be. I had this wonderful conversation with Mary Pernicki out at Stanford about wildfire smoke, and the[00:19:00]question was essentially, obviously what can each of us do for ourselves in those situations, but obviously the, the greater fight of trying to reduce the, the severity, these, her point was no one knows more about this than I do and I know it's pretty damn bad, but I don't know how bad, and it's gonna take some time because any exposure to that kind of stuff really matters. And like you said, the, the little AirNet, right? AirNet four, is that what it is? You know, it's not gonna tell you the particle count of anything. What it's gonna tell you is just like, is your air stale essentially?

Like, is it not being circulated much less, sort of, like you said, it can be cleansed, but it can still be a, a closed room also. That can be more complicated if you're in a place that's where the outside air is also contaminated in some way, cuz you can't just bring in outdoor air. Now I know the administration at one point, the federal administration, I don't remember what the mechanics of the legislation were, but there was an enormous amount of money they put out for schools and offices to go after their HVAC. And obviously again, it's not just money that's gonna do that.[00:20:00]We have a massage shortage of electricians and HVAC installers and, and all kinds of things like that. It's not as easy as here's a check, go rip everything out. Kids are in school, this and that. Do you have any knowledge of sort of how that's going, how much uptake there has been there?

Um, any common obstacles that folks are running into on that front?

Linsey Marr:Yeah. You know, I was involved in discussions kind of with the White House Office of Science and Technology policy. And I know a colleague has said that, you know, only a minority, a small amount of that money has been spent so far, which is, which is fine.

They, they still have time to spend it. You know, there aren't enough HVAC technicians in the world for everyone to call on them all at once to come upgrade their systems. But over time, you know, I do hope that money gets spent on upgrades to HVAC systems, other things to, to improve air quality. I think there's, there's some barriers.

One is that a lot of people still don't appreciate, I think the importance and the impact they can have by upgrading HVAC. A second is, of course, having the expertise around HVAC[00:21:00]technicians. I ran a workshop put on by the National Academies where we had someone from facilities engineer with a school district and he said yeah, people just don't know what to do. So I think we need more explicit guidance about what to do. And there, there are some really good resources out there. CDC has a really nice webpage on ventilation improvements and EPA came out with The Clean Air and Buildings challenge, and they have a kind of a tip sheet, like it's two or three pages long, but with very specific things that you can do to upgrade your HVAC system or upgrade your ventilation ranging in cost from very low, like opening windows at certain times, or building your own air filtration unit called the Corsi Rosenthal box with a box fan and four air filters to upgrades of your HVAC system. One, you know, one place we really need to start is just making sure that your HVAC system, if you're in a big building, making sure that the system is working the way it was designed to[00:22:00]work.

Cuz I think a lot of these have just fallen into neglect and they're not really working the way they are supposed to work. So that, that's really the place to start. 

Quinn:So many of our issues now and as we confront the climate impacts that are coming towards us, whether they're ones we can slow like heat or ones we cannot, like sea level rise, are going to be because we tend to build infrastructure and then never touch it again.

And I know that so many of the public schools are just in shambles. Teachers with 30 plus kids in the classroom and it's hot and it's smoke and it's mostly black and brown kids who, who are in these just garbage schools, which isn't any fault of the teachers or administrators. We just don't touch these things so it makes sense.

You gotta start at the base level, like does the HVAC work, is there HVAC, does it work? Does it do anything? Are there any filters? When have they been changed? Is there mold in the system? Things like that. It's a tall ask, but it does seem not to be too dark. But you know, I remember after the Newtown shooting thinking, if we're not gonna deal with guns, now, when are we gonna do that?[00:23:00] 

And it feels like we've still got four or 500 people are dying a day in the US which is 140,000 a year or whatever. When are we going to really start pushing this as much as we can? Understanding that the, the logistical difficulties and the political and economic difficulties are a lot, but it just seems like this is the window to do that.

Linsey Marr:Yeah. This is our golden opportunity and things are happening. So that's good, baby steps. I would say if there is some kind of state level or federal level indoor air standards to kind of parallel what we have for outdoor air, things will happen. 

Quinn:Yeah. Have you reconsidered or are you like, we're already nailing it?

How have you reconsidered or if you could go back to the beginning sort of building your team and how you teach and how you communicate and how you try to be effective. Now, knowing what we know and how difficult this all is and the opportunity we have and, and that there will be future pandemics and we're still dealing with measles and flu and all that stuff, how have you thought about, okay, I need to[00:24:00]approach this in an even more multidisciplinary way or interdisciplinary way, or maybe I'll bring in, uh, more economics folks into my team so we can think about that level, whether it's micro or macro, has that affected your job at all and how you approach everything? 

Linsey Marr:Yeah, it has a little bit. Um, in recent years, I would say I've kind of always appreciated and sought to have a, an interdisciplinary or multidisciplinary scientific and engineering team. So I've tried to bring in people with backgrounds in mechanical engineering and microbiology and environmental engineering, aerosol science, atmospheric chemistry.

So I really like having that mix of diverse backgrounds in our group. We don't know necessarily early on what the other people are doing or talking about, but through over time and working together, we, we do get there and I think we are able to break through some, some of those disciplinary boundaries and look at really these interesting problems.

But I have become convinced, and actually I'm glad you brought this up, that in order for us to make more progress on this, it's not just standards, but it's[00:25:00]actually showing that there is an economic payoff to be had here. So I have been thinking about teaming up with economists, for example, to look, do more of these careful kind of benefit cost analyses to convince people, Hey, you know, this makes sense.

We're leaving money on the table if we don't upgrade our HVAC in terms of absenteeism and health costs and productivity. So definitely that. And then on the, you know, I've collaborated with a historian and an English student or rhetoric student, and that turned out amazingly well to really try to understand where this kind of misunderstanding about transmission came from. And so that was really key because yeah, I could sit here and say, I'm right, you're wrong as much as I want. But in order for people to appreciate that more, they, they need to understand why and where that's coming from. Why our, why was our understanding wrong?

Quinn:If I can interrupt you, can you speak for a minute about that a little bit? So, cuz it does matter again, as much as I'm trying to push forward and effect[00:26:00]as we say, like a better today and tomorrow. It doesn't matter how we got here because it improves our ability to course correct as we go. Cause we're certainly not gonna keep getting it right. So I, I would love if you could share a little bit about that. 

Linsey Marr:Yeah. I had always wondered, since I first started reading papers about flu transmission, they always talked about, oh, there's droplet transmission. Those are the large, visible wet droplets that spray onto someone’s face, and then there's aerosol transmission, and it talked about a dividing line between these, a, a certain size of droplet, and it, it always talked about five micrometers or maybe 10 micrometers.

Now I know that I know what that means, but size wise, but let's say your, your hair is maybe 50 to a hundred micrometers or microns in diameter. So we're talking about something that's 10 times smaller than the width of your hair. And it was just totally wrong because I knew and other aerosol scientists know that a particle that has five microns in size floats around for a long time. That is not. Things a little bit larger than that are not behaving like these ballistic cannonball[00:27:00]type of droplets that fly into someone's face. If I release a particle that's five microns in size, from the height of my nose when I'm standing, it takes half an hour for that to fall to the ground.

Quinn:Is that because it's so light

Linsey Marr:It's very light. It's very small. Yeah. It just takes a long time to, to fall to the ground. That really bothered me. And that was, I don't know, 15 years ago. And there was one other person at the University of Hong Kong who I talked about with this, and he was also frustrated by this misinformation or misconception and so he kind of did some digging and he really hit a dead end.

He wrote about this in a paper. He published a couple years ago. I really wanted to know where this came from and you know, the pandemic kind of accelerated that. And then I spoke with a colleague at University of Colorado, Jose Jimenez, and he was saying, well, in atmospheric chemistry there was this myth that was, you know, everyone went back and cited this one paper.

But it turned out that paper didn't say what everyone thought it said like, it just kind of became embedded. Everyone just cited it and so everyone else just cited it.[00:28:00]And, and in fact, a lot of people cited a certain paper from 1936 by William and Mildred Wells about this idea of airborne transmission and this five micron cutoff. In reading through that paper, I could not find any mention of five microns. In fact, they talked more about 100 microns, which is correct. So I was really frustrated and curious about where this idea the incorrect physics came from. I had known a historian at Virginia Tech, history professor who studies pandemics because he was running a workshop for teachers and wanted to, several years ago, wanted to come, you know, bring them to my lab so I could talk about flu transmission. So we did that and he and I, at the beginning of the pandemic kind of corresponded occasionally about mask wearing and kind of the history of that. So anyway, I reached out to him and said, Hey, we've got this question, you know, where did this wrong idea come from?

And he suggested, well, we need, you know, we need to get someone who studies medical rhetoric on board, which is a study of how certain ideas[00:29:00]take hold. So he brought in, recommended a graduate student, Katie Randall. And, um, she's the one who really did the hard work. So we, we had, you know, several meetings over the period of several months and kind of talked about this problem.

She started digging through the literature, kind of doing backwards and forwards citation searching. And eventually she, she had this kind of breakthrough where she determined that this idea and our, all of the thinking about airborne transmission came from tuberculosis. And so tuberculosis is caused by a bacteria.

The thing that's a little weird about tuberculosis is that you breathe in the bacteria, but it can only in cause an infection if it gets deep in the lungs. That's where there's the right cells where it can attack. And in fact, to reach the deep lungs, it's really only those very small particles that can reach the deep lungs, smaller than five microns.

All of our, tuberculosis became the basis for all of our understanding, I think about airborne versus droplet transmission. Even though with other respiratory diseases, particles that are larger than five microns, you can[00:30:00]breathe them in and they can like attach to receptors in your nose or somewhere higher.

They don't need to get to your deep lung to cause infection. 

Quinn:It really does matter because it's just, again, like it's the whole, like if you could take a time machine and change like one small thing, what's the butterfly effect? I'm like, this was the thing that everyone banked on. 

Linsey Marr:This was the thing. CDC started saying this back in the nineties or so about, oh, airborne transmission involves things smaller than five microns. Droplet transmission involves things that are larger. This kind of became further entrenched with the original SARS outbreak in 2003 when the medical community became convinced that it was transmission occurred only when doing certain medical procedures like intubating someone in the hospital and that generated aerosols. Um, but otherwise you would not generate aerosols. But I think they, they also didn't realize that when we talk or breathe, we are releasing aerosols. Talking and breathing is an aerosol generating procedure. But they didn't recognize that.

Quinn:Thank you for sharing that. I mean, it's, it's so instructive.

It's different,[00:31:00]but parallels a little bit the news about the past 20 years of Alzheimer's research that's sort of come out this year about how the first study was fabricated a little bit and then it turns out that is what we have based all of our research and funding on all the brain plaques, everything.

And what's the best way to phrase this? I fully understand when the smartest brain folks say, the more we pull the string, the more we discover like what we don't know about this incredible machine, right? But at the same time, to have so much money go again to go into something like Alzheimer's treatments, preventions, whatever it might be for so long, and to constantly have everything fail, at some point somebody goes, but why?

You know, but, but why? Like, what? What do we have to go back to? And I feel like one of the things I get asked about a lot from folks is when we made the move to focus so much more on, I guess, personalized medicine and less on public health. Over the last hundred years, there was the low hanging fruit of like, turns out you should wash your[00:32:00]hands and your water should be clean.

Don't poop where you eat. Don't put things in the water. Don't bury bodies, you know, next door. But at the same time, it does seem like. We stopped revisiting these things and that's why it's always so interesting to see all these new meta studies, right, which go back and try to replicate old studies about whatever it is, psychology, anything, and to see how often they do fail.

Linsey Marr:There's an interesting kind of rationale for part of why I think there's been a dearth or lack of research in this area, which is that up until through the 1970s, there was still a lot of studies, papers on kind of survival of viruses and bacteria in droplets and air in aerosols. It kind of stopped, and I've read, I don't know if this is true, that maybe one of the reasons that stopped is because then we had lots of antibiotics, which crushed infections, and so we were no longer worried about infections.

Cancer became the thing, and then research in this area pretty much stopped.

Quinn:It's unfortunate, big fan of the 80 20 theory. For instance, 80% of your, if it's a company, 80% of your profits come from[00:33:00]20% of your company customers, whatever it might be. It's the idea that, like to simplify, if you one big lever, like get everyone to stop smoking is gonna fix a lot of things, right?

Both lung cancer and it's gonna make people go to restaurants more. All, all these different things. You hinted early on about how you, you understand, obviously because you've always sort of had this multi-disciplinary approach to things, and especially over the past few years, that it's not so easy as just saying like, look, if we clean the air, the people are gonna be healthier.

Not everyone will get COVID. The enormous amounts, both in variety and magnitude of the co-benefits from something like cleaning indoor air from kids who are just gonna be in school more. I get an email every week from school saying, listen, your kids, I mean, my kids don't really miss that much, but the point is like, they don't have to get sick, but also they stay in school more, and most schools get their funding from how often the kids are in schools and people will be at the office more if they're healthier.

It's the same thing as the co-benefits from paid sick leave or paid family leave or things[00:34:00]like this. It's like. All right, fine. If we're not gonna fund childcare in this country, then you have to have, people have to have the ability to stay home and take care of the kids, otherwise they're not coming to work for you, you know?

And then GDP is lower if we still want to keep thinking about that, whatever it is. But I come back to this idea of, feel free to shoot this down. Sometimes it seems like from a human perspective, societal perspective, there are things we encounter that are maybe too big or too complicated or require too much change that we kind of don't want to be true.

Linsey Marr:Climate change, for example. 

Quinn:Climate change. The fact that we have made so many strides against this, but in part because, the booster uptake is so low, in part because we didn't vaccinate the world. All these things, we're still gonna lose 140,000 people this year. Right. We got a new top six cause of death and we've sort of normalized that and moved on from it.

I guess. How do you feel like that may have pushed back against your arguments in the beginning? That no, listen, we have to think about this as airborne. I guess. What was the waterfall, if everyone had said[00:35:00]yes, okay, great. It's airborne. What did that actually require from them? If they acknowledged that that was true, I guess what logistically would that have required from a healthcare perspective, from an industrial perspective, things like that.

If for them to say they can't just say yes, that means what else did they have to do for that to be true? 

Linsey Marr:That may have been one of the hurdles to wider and more rapid acceptance of airborne transmission, because if you say, well, this is an airborne virus, that means in healthcare settings, so hospitals and everything's, my airborne is kind of like a, a trigger word, and it means that you have to provide all the workers with N 95 respirators that have been so-called fit tested.

So they have to go through and make sure they're, they sealed well to the face, then all the patients are supposed to go into negative pressure rooms called Airborne Isolation infection rooms. Costly. There are not enough of these types of patient rooms in hospitals. So I think there was a real reluctance to say the word airborne in, in healthcare[00:36:00]and in infectious disease control settings.

That was a, a barrier. And then it would also. Be, well if it's airborne, then maybe some people think, oh, there's nothing we can do about this. We have, we give up, you know, I give up. But that's not true cuz we know there's things we can do. Things like masking and you know, having cleaner air, better ventilation and filtration took a lot of people, I think just thought of airborne transmission as this like really mysterious, dangerous thing.

I don't know if you saw the movie Contagion. Some airborne pathogen that was killing lots of people and this guy's in a movie theater, and he looks up at the ventilation system at the vents and he sees, you know, they visualize its cartoon. Of course, whatever the pathogen was, the virus coming out and blowing towards him in the air.

It's like, oh my gosh, it's everywhere, right? And there's nothing you can do about it. So I think airborne transmission has had that connotation associated with it. So I think there was some fear about saying that. 

Quinn:I apologize if that didn't make any sense. If you have any sort of responsibility in an[00:37:00]organization, whatever it might be, or to a family or a class acknowledging something, it doesn't usually stop there.

There's usually a laundry list of actual practical ramifications that come with that. And, and again, I do to try to make the, our, our community and, and folks in general, as effective as they can be. It does, it is important to stop and try to empathize with those things. You can't just say too bad that's the way it is.

It's like, you know, the arguments for de-growth, it's like, sure, that sounds great, but like how politic politically feasible is that. Not a lot , you know? So you, you do have to work around that. Sure. You can then take a further step back and try to elect more people who, who agree with you and change it that way.

But the point is like, it's not so easy and I, I don't wanna pretend it is, but at the same time I'm a big fan of, uh, there's an economist Mariana Mazu Cado, and she wrote this great book a couple years ago called The Mission-Based Economy, I think, and to very simplify it, it's essentially like, okay, if your mission is put a man on the moon and bring him home alive, that's very clear.

It's very[00:38:00]measurable. He either gets there and he comes home. or he does not. And what you can do is then reverse engineer and design all of your teams and processes and milestones against, is that going to get us there? Is this thing you wanna ship with it? Is that gonna help achieve that? If not, get it outta here.

Are these milestones along the way? And it's the same thing for net zero pledges, or like you said, designing clean air standards for inside, whatever it might be. Or water. It does seem like setting that helps because then you can help to maybe remove some of those limitations and make those logistics easier all along the way for folks, like you said, we just didn't have those negative pressure reps.

Linsey Marr:Well, yeah. We also didn't have clear goals, I think was it to prevent as many deaths as possible. Well then we'd be in lockdown forever. That's not feasible. Sure. You know, I would like to think we would all agree that maybe the goal is to avoid overwhelming the healthcare system, but I don't know if that was ever clearly stated, that makes it harder. So it was kind of this big nebulous goal maybe or not[00:39:00]non-defined goal. Lack of goal. I guess that hamstrung us too. 

Quinn:So if you could be the, take your role as Oracle of air quality and become as Americans like to say, the our air quality czar. What, what are your first sort of few moves?

Understanding the where we are politically, sociologically, economically, across the board to let's say starting with federal air standards, you know, what are the things that you feel like are measurable and achievable? 

Linsey Marr:I would probably set some kind of federal standards like we have for outdoor air, and these would apply to public buildings, so where there's lots of people, you know what goes on in your house can stay in your house, you know, it's up to you. And yeah, your friends come over. But in places like schools and grocery stores and you know, performing arts centers where lots of people congregate, I think there's a couple of standards that would make sense. One of those would be fo carbon dioxide levels as an indicator of ventilation.

As you know, we talked[00:40:00]about the airnet four sensor, um, and keeping that below a certain level. And then the other would be for particles in the air, total, kind of total particles in the air. Again, cuz it's not just about viruses, but it's about the other things. The cigarette smoke type particles, which are all around us.

Quinn:Do we have accessible ways of measuring particles that, for instance, with effort could be rolled out to schools? The version of airnet four.

Linsey Marr:Yeah. You know, there's already lower cost sensors that can measure particles reasonably well. There's something called like the purple air..

Quinn:Oh, that's right. I forgot they do an indoor one now too. 

Linsey Marr:It's the same, same sensor. You just put it indoors and then if you go on their map, it has like a black, bold line around it. To show that it's indoors, so yeah. You could have that indoors and those are. I know I bought mine. I have a whole box of 'em. $150 each. If you put those in your school and things, okay.

And then, you know, like a carbon monoxide alarm, if the level goes above a certain amount, the alarm goes off, or a smoke alarm, it goes off and you realize, okay, we need to do something here to, uh, you know, our air quality's gotten really bad. It's harming[00:41:00]us. We need to, you know, crank up the HVAC system for a bit, or, you know, upgrade our filters or bring in a, a portable air cleaner for, you know, this period of time.

Quinn:That makes sense. It all seems so rational.

Linsey Marr:But you know, it costs money and that's…people don't wanna spend money. There's all those competing priorities, but that's where I think the economist and cost benefit analysis comes in. If you can show that, you know, doing these things is gonna have a 10 times payoff, then maybe people will think about it more seriously.

Quinn:One would think we're, we're big on the bean counting. Um, it does seem like the more you can, if we can't visualize these things with your magic goggles, uh, then hopefully we can show people how it'll just save their company or their state or whatever it is some dough. Or actually increase it because again, people will be there more.

Any other specific sort of recommendations, uh, you have for, again, folks with any sort of organizational responsibility, whatever it might be? Again, the AirNets great for showing just is your error stale? It's co2. I put one in my little workout room where my StairMaster is. Not great. Dr.[00:42:00]Marr, let me tell you after five minutes it, it is lucky I'm not passing out in there.

Linsey Marr:Well, it's all that heavy breathing you do when you're working out. 

Quinn:Yeah, it's, it's not ideal.

Linsey Marr:But if nobody else is in there, it's just you then. Right. 

Quinn:And then someone will find me on the floor someday. It'll be fine. My children are waiting for that moment. Okay. And then the purple air is great. And you feel like those, uh, work pretty well.

They were so popular and I, I definitely picked up a few of them myself. 

Linsey Marr:Yeah. I think they, they, they work well enough. Okay. So that kind of tells you what's there, but what can you do about it? The other thing that I've done since the pandemic and other people have done is to get one of these portable air filters.

High efficiency, particulate air, hepa type of filters for rooms. So we, you know, I got one for the house and we run it when, uh, someone's sick. And if I lived in somewhere with wildfires, I would definitely be using it then. When we have a cooking accident, for example, and there's lots of smoke in the air, we can use it then.

To help, uh, bring down the particle levels cuz we're coughing and everything. So I think that's a, a good tool. To have around,[00:43:00]especially if you live in a place with lots of wildfire smoke. Yeah. 

Quinn:Yeah. I, I've definitely got a few of those. We've got some pretty heavy dust allergies in my house, and, and we run those and I'll show the kids every, I think it's like every two weeks the alert pops up, I open it up to vacuum off the things and the kids are just like, oh my God, like, What is all of that?

I'm like, that's what this thing is doing. 

Linsey Marr:Yeah. Well that's what's getting into your lungs too, cuz your lungs act like a filter in a way too. So that's the same stuff you find on your filter. That's what's going on your lungs. 

Quinn:That is super helpful. I have a last couple questions I ask everybody and I'm gonna get you outta here.

Is that okay? Sounds great. You're the greatest. Dr. Marr, when was the first time in your life when you realized yourself, your team, running for school council, whatever it might have been. When you had sort of the power of change or to do something meaningful, when were you like, oh, I moved the needle on something that I care about?

Linsey Marr:That's probably like teaching, helping students understand something that they didn't understand before. And I would say that happened as early as when I was an undergraduate. I was a[00:44:00]TA for some courses and then as a graduate student also, I was a TA teaching assistant for some courses and really saw that.

You know, people talk about that aha moment. It is really rewarding and it's like all of a sudden you've helped someone gain new knowledge. They have a better understanding of whatever it is. So yeah, that's what I would say. 

Quinn:Who is someone who's positively impacted your work in the past six months?

Linsey Marr:Okay. I have a collaborator, Seema Lakdawala, who's at Emory University. She's a virologist who studies flu, and she and I have known each other for a long time, but I feel like we always just riff off each other on when we start talking about science and we're working on a, a paper right now, that's, that's pretty tough in responding to reviewer's comments.

And I feel like, you know, she's always pushing us to really understand what's going on and to have, you know, have a, make sure our analysis of the data is as good as possible and that we are thinking about everything we can and being as careful as we can. So, thank you Seema. 

Quinn:That's an important[00:45:00]collaborator to have, for sure.

Last one is, what is a book you've read? Obviously this year is pretty new, but in the past year or so, that has either changed your mind on something or influenced the way you think about a topic. 

Linsey Marr:The newer, latest book by Celeste Ing, which was, I can't remember the title of it. It's kind of pandemic influence, but it's about a kid who's, you know, they're worried.

There's been a lot of, I think, anti-Asian sentiment in the country. This is all fiction, of course. The kid's mother has left so that the kid wouldn't be taken away from his father. And it was about the kid trying to find his mother and the role of librarians, which I have newfound respect for.

They operated almost this, like, this underground railroad of kind of helping kids find their, their parents. And so it's, it's given to me greater appreciation for librarians and also kind of the, the parent-child bond. How messed up society can be sometimes. 

Quinn:Yeah, I think that's all fair.[00:46:00]I am a huge fan of librarians and now take my children to the same 50 yards that way, the same childhood kids portion of the public library that I went to as a kid and encouraging them.

Don't ask me for help. Go introduce yourself. Talk to them about the things you like. Ask for the help. That's what they're literally went to school and trained to do. And just watching their enthusiasm and their, their intentionality and, and the caring they have for obviously not just like a specific kid, much less my kid, but about that making sure that they are tending to their curiosity and, you know, nourishing their passion for curiosity and for learning and just being in that space. It's so amazing to watch. 

Linsey Marr:Yeah, I'm all about curiosity and knowledge and building our knowledge, um, about, you know, every, everything really. And the librarians are like the superheroes of that.

Cause they, you know, you go to them, they don't know it all, but they can help you find it.

Quinn:Yeah, yeah. A hundred percent. If you were the librarian on air quality and a bunch of nerds[00:47:00]who, who listen to podcasts wanted one place to start. What would you recommend when they came to your desk? 

Linsey Marr:Like a textbook?

Do people read textbooks anymore or like a website or - 

Quinn:I'm gonna plead the fifth on whether I did enough reading in my textbooks, but, uh, where would you say, Hey, yeah, it's, uh, start here. If you really wanna understand sort of the mechanics of it.  

Linsey Marr:I'm gonna say people don't read textbooks unless they have to, cuz they're in a taking some course.

But there's a lot of really good information on the US EPAs website about air pollution. They're responsible for it. They also have good information about indoor air, hasn't been their domain, but there's a group of researchers there who, who specialize in that. And so I would kind of start there with, we call them criteria pollutants.

These are ones that are regulated and that are measured in all across the country. So look up criteria pollutants, and there's lots of great information there about them. And then trying to think if there's like some kind of fiction. What we need is like some dramatic plot book about air pollution.

Then I could send people to that kind of like there, there has been that[00:48:00]for, I forgot the name of it, but for water quality.

Quinn:Dr. Marr, I can't thank you enough for your time, for, for being such an important voice over the past few years. I'm sorry, your Twitter following has grown so much, but at the same time, Twitter might be over during this conversation who can know?

We'll find out when we get off. Thank you. Truly, I, I have learned a tremendous amount from you from a distance, and it has been a pleasure and an honor to, to have you on, to learn a little more. 

Linsey Marr:Thanks so much for having me. I've, I've enjoyed talking about my, my passion, of course, and thinking about it in new and different ways from your questions.

Quinn:Awesome. Rock and roll. That's it. Important, Not Important is hosted by me, Quinn Emmett. It is produced by Willow Beck, edited by Anthony Luciani, and the music is by Tim Blaine. You can read our critically acclaimed newsletter and get notified about new podcast conversations or YouTube conversations @

That's also where we've got fantastic t-shirts, hoodies, coffee mugs, and I'm on Twitter if it's still there at[00:49:00]Quinn Emmett, Q u i n n e m m e t t, or we are at importantnotimp, because there's not enough characters. We're also on LinkedIn. You can search my name or important, not important there. Please send us feedback, guest recommendations, cookie recipes, whatever you'd like on Twitter, or

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