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Sharon Chinthrajah: The air is making us sick

The connection between bad air and bad health is growing clearer by the day. One allergy specialist says that real change starts at home, but ends on a much larger scale.

We need large-scale efforts to battle air pollution, says Stanford allergy and asthma specialist Sharon Chinthrajah. | Unsplash/Fabian Møller

We need large-scale efforts to battle air pollution, says Stanford allergy and asthma specialist Sharon Chinthrajah. | Unsplash/Fabian Møller

Air quality affects our health far more than many would suspect.

It’s closely related to asthma, of course, but also to concerns like cardiovascular disease and other lifespan-reducing conditions. It’s a health emergency, says allergy and asthma specialist Sharon Chinthrajah, a clinical associate professor of medicine at Stanford who studies and develops strategies for combatting conditions caused by air pollution.

She says there are a number of ways we all can do better, including changing clothes frequently and showering in the evenings to wash away the day’s detritus collected on hair and skin.

But, she says, those efforts are only stopgaps to truly solving the problem of air pollution. The most effective responses have to come at a societal level, and there, Chinthrajah says, we must target the biggest contributors — motorized vehicles that burn fossil fuels. Eighty percent of California’s air pollution comes from these sources. Often concerns about air quality are accompanied by racial and class aspects, as people of color and the poor tend to live in urban, heavily-trafficked areas.

Chinthrajah advocates for large-scale efforts to battle air pollution, particularly a move toward electric vehicles and public transportation. She notes that in California, low-income families can qualify for up to $20,000 in state, federal and local subsidies to purchase electric vehicles, putting clean cars within reasonable reach for the first time.

Join host Russ Altman and allergy specialist Sharon Chinthrajah for an exploration of the connection between air pollution and health, and what we all can do to lessen its influence on our well-being, on the latest episode of The Future of Everything radio show from SiriusXM. You can listen to The Future of Everything on Sirius XM Insight Channel 121iTunesGoogle PlaySoundCloudSpotifyStitcher or via Stanford Engineering Magazine.

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Russ Altman: Today on The Future of Everything the future of air pollution and asthma.

Now there’s an undeniable link between air quality and human disease and welfare. Perhaps the best and easiest to understand is the link between asthma, difficulty getting air in and out of your lungs because of inflammation in the airways, the link between that and air pollution. Of course, air pollution is affected by human daily activities like factories, vehicle emissions and other things, as well as big events like forest fires and other natural causes of air pollution. News stations are now telling us almost everyday about air quality ratings. Sometimes they even tell us don’t go outside or if you’re ill don’t go outside. Because they can’t really tell us not to breathe so they have to tell us something else.

Now, there are movements for people to reduce their carbon footprint and many of us try to use our intuition to make good choices. But not always with good information about what will make the most difference. I recently took an online quiz, I don’t know why I took this quiz, I think somebody told me to take it, that assessed my understanding of the different activities that I did and what their impact on the carbon footprint my carbon footprint was. And I did terribly, I believe I scored a 25/100 so I’m not proud of that.

But I remember one of the things I didn’t realize is that throwing away food turns out to be a huge, bad thing because of the amount of energy it takes to create the food, transport the food, clean and cook the food. That when you throw out extra food it turns out to be an inordinate amount of waste of energy and resources. So there you go. So, I have not been throwing out as much food in the last 3 days.

Cars are another big opportunity there have been strides in reducing emissions and combustion, gas engines, but these pale in comparison, I think, to the very low emissions of electric cars. The infrastructure for electric cars, however, is still being developed and they are costly and there are other logistical challenges to getting yourself into an electric car.

Dr. Sharon Chinthrajah is a lung and allergy specialist and a professor of medicine, pediatrics, immunology and allergy at Stanford University. She works on these issues. Sharon, what are the main sources of air pollution? And how good are we at monitoring these?

Sharon Chinthrajah: Thank you so much for inviting me to your show to talk about these important issues. You know air pollution is made up of different components. We do a good job of monitoring it with the air quality index and that measures ozone and particulate matter down to 2.5 microns. To put it into perspective the thinnest strand of your hair is about 70 microns. So we’re talking about really small particulate matter.

Russ Altman: And who makes these AQI air quality index measurements?

Sharon Chinthrajah: That’s a great question. I think it’s government agencies that measure the air quality. There’s different stations around the state. And they kind of figure out and disseminate it through

Russ Altman: Okay.

Sharon Chinthrajah: So anybody can go to and plug in their zip code and find out their local air quality index. And this is something that I advise all of my patients to do particularly those who have respiratory illnesses.

Russ Altman: And as a lung specialist, do you feel that this measurement is a pretty reasonable measurement in terms of the scientific basis for acting on it like not going outside that day or staying inside, these are all reasonable things?

Sharon Chinthrajah: Yes, very reasonable. And in fact, you know, over the summer and even now we’re having air quality days, spare the air days.

Russ Altman: Spare the air, yes.

Sharon Chinthrajah: So this is also another measure where there’s public announcements to make people aware that there is going to be poorer air quality because of different factors so high temperatures, different air pressure systems, wind movement that then kind of make the air quality or smog very apparent for that day. And it encourages people to do whatever they can to limit their contribution to the air pollution and their exposure.

Russ Altman: Now you see the effects of these bad air days I would guess, in the clinic. Does the clinic actually change its activity from day to day based on the air quality? Or is it more of a long-term problem?

Sharon Chinthrajah: It’s more of a long term problem. I definitely see the effect in our clinics. You know, poor air quality affects everybody. Healthy people and people with chronic heart and lung conditions. And you know, in my lung clinic I see people coming in with exacerbations of their underlying lung diseases like asthma or COPD.

People also have uh just, normal healthy people can be irritated when really poor air quality days are present. With irritation just from the pollutants on the surfaces. Anything that the air comes in contact with so your eyes can get irritated, your nose might feel like you know you have irritation or runny nose, or a tickle in your throat because of post-nasal drip, or throat irritation, and maybe even itchy skin. And in combination with anything else that’s going on so if you’re in allergy season, the two can work together and make your symptoms even worse.

Russ Altman: Yeah all of those experiences resonate with me. Are there things that people can do kind of low-tech ways, so there’s this idea of staying inside, we’ve seen some people wearing masks. It looks a little ridiculous but maybe it’s not so crazy. Do you recommend masks? Should people take allergy medicines when they are getting these kinds of irritating symptoms? Are there things for the skin? Just kind of, are there basic things people can do when they’re experiencing one of those days?

Sharon Chinthrajah: Yeah, no. Those are great questions. One thing that I tell all of my patients when they come to see me is to prepare for bad air quality days. We don’t know when they are going to hit, we don’t know when there is going to be natural disasters like wildfires, or other things that make the air quality poor. So I do encourage for really poor air quality days that people do wear a mask when they are outside.

Russ Altman: Okay, so it’s not crazy.

Sharon Chinthrajah: It’s not crazy. And the mask has to be well fitted to the face so that it’s really doing a good job of filtering the air that you’re breathing in.

Russ Altman: So perhaps, tying a bandana in front of your face is not going to do the trick?

Sharon Chinthrajah: It’s not going to do the trick.

Russ Altman: Even though it might look cooler. A white medical mask.

Sharon Chinthrajah: Yes, and nowadays you know you can purchase things online that are cool air masks that filter down to particulate matter 2.5 microns.

Russ Altman: That’s the key.

Sharon Chinthrajah: That is the key. And so when you’re outside in these poor air quality days. So now the air quality index has a range of different colors and different levels 0-50 is typically thought to be good, 50-100 is okay, and then above 100 is where people who are susceptible or have chronic illnesses might be affected by poor air quality, above the level of 150 which gets you into the red range and maroon colors than anybody, even healthy individuals can be affected by air quality. So this is something to pay attention too.

Russ Altman: This is The Future of Everything, I’m Russ Altman. I’m speaking with Sharon Chinthrajah about air quality and some of the interventions we can make to help our personal experience of poor air. I’m sorry, I interrupted.

Sharon Chinthrajah: No, thank you. And so when you see those different measures, you know, you try to limit your time outside, like you mentioned, particularly when you get above an air quality index of 150.

Russ Altman: Okay.

Sharon Chinthrajah: You can wear masks when you’re traveling outside and if you have to be outside, for your job, particularly for people who have outdoor work really this is important for them. To stay hydrated. If you do experience irritation in your eyes, or your throat really to go inside and wash your eyes away, wash all of the air pollutants that are stuck on you away from your face. I tell people who are more susceptible that if you’re spending time outside and then you come inside, to change your clothes even.

Russ Altman: Wow. Because it kind of becomes a carrier of all this stuff.

Sharon Chinthrajah: Yeah. Stay hydrated. And then when you’re traveling in between places to recirculate the air in your car. Make sure that your air filters are okay, that you’re not keeping your windows down. Really be mindful about limiting your exposure to the poor air quality outside.

Russ Altman: Wow. So these are good. And one other thing I wanted to ask about was skin. It’s kind of related to the clothes. Is it true that showers, increasing numbers of showers could be useful under these situations? Or is that not really known, or useful?

Sharon Chinthrajah: I don’t know that it’s known. But I don’t think it’s a bad idea to particularly at the end of the day if you’ve been outside in poor air quality all day, to change your clothes and just have a quick rinse off. To remove any air particulates that might have deposited. Before you lay down on your hair and sleep on anything that might’ve been caught in your hair or on your skin for the next you know, eight hours or so. That’s what we also tell our allergy patients in allergy season you know. To kind of take a shower at night to wash all of that away.

Russ Altman: So it’s almost as if this bad air gives everybody some sort of kind of allergy? Or at least those allergy symptoms. Well, I know that in addition to your clinical practice your research interests are in emissions and air pollution, and the health effects. And can you tell us what are the big questions you’re approaching in your research?

Sharon Chinthrajah: Really is, what does poor air quality or bursts of poor air quality, do long-term to the immune system. We’ve seen in areas, in developing countries like India, Asia, where they suffer poor air quality days many days of the year, that the life span is shortened. You know, there’s premature deaths, there’s exacerbation of underlying lung issues, cardiovascular issues. There’s more deaths from heart attacks and strokes in countries where there is poor air quality.

Russ Altman: I’m sure that people who are listening are wondering those countries often have many many health challenges in addition to the air quality. So have people been able to tease apart the contribution of the air versus water problems or food access? Do we know that the air itself is one of the causative factors in these diseases?

Sharon Chinthrajah: Yes. There have been long, nice studies published by the WHO. Looking at the contribution —

Russ Altman: This is the World Health Organization, not the rock band.

Sharon Chinthrajah: Thank you.

Russ Altman: I don’t think they published much on air quality. Certainly in sound quality, they’ve made a lot of statements.

Sharon Chinthrajah: Yes, thank you. And so these are ongoing investigations you know, it is hard to say definitively that it is poor air quality, because you’re right there’s many many issues in developing countries for access to health care, etc. This is one of the things that our center is very keen on investigating is, what are the short term consequences on the immune system and immune development and what are the long term consequences?

Russ Altman: Now you’ve had a lot of discussion in the press that I reviewed before we met today. Particularly on car emissions, and I think you even went on record of saying you drive an electric car and you do it for a reason, not just for fun. Tell me about car emissions and where we are today, where we need to get to, and some of the things you have been looking at in advancing that agenda.

Sharon Chinthrajah: Yeah so thank you so much. Car emissions in California account for 80 of air pollution in California.

Russ Altman: Oh so this is huge.

Sharon Chinthrajah: Yes.

Russ Altman: This is not a little fraction. This is the majority.

Sharon Chinthrajah: Yes. It accounts for about 50% of climate pollution. And this is a problem of the Industrial Revolution really is burning fossil fuels and the emission of carbon dioxide into the atmosphere. Carbon dioxide now counts for 76%, up to 76%, of greenhouse gases. And greenhouse gases are important because it contributes to the atmosphere’s ability to trap heat on Earth. Without greenhouse gases, we wouldn’t be able to have warmer temperatures on the planet and life wouldn’t be sustainable.

Russ Altman: So up to a point, they’re our friend.

Sharon Chinthrajah: Yes. But since 1970, the increase in carbon dioxide has increased by 90%. And the majority of that increase in carbon dioxide is from the combustion of fossil fuels. And so, you know humans create a lot of carbon dioxide just in the way that we live by breathing and digesting food. There are natural combatants to that carbon dioxide we have trees, and plants that utilize that carbon dioxide as their own food with water and sun and photosynthesis.

Russ Altman: Kind of a miracle.

Sharon Chinthrajah: Yes. To then take carbon dioxide out of the air. And create oxygen and other organic compounds right? The problem is, is that we are making more carbon dioxide than the plants and vegetation can absorb. And so this is a health emergency. Because our rate of carbon dioxide production it just continues to rise.

Russ Altman: So this is The Future of Everything I’m Russ Altman I’m speaking with Sharon Chinthrajah about ,right now, our carbon dioxide, greenhouse gases, and the contribution of motor vehicles. So you said 80%, that was a big number for me to hear, 80% of Californian pollution is from cars. Even though I think of California as one of the most aggressive states at trying to curve emissions. But I also know that we have a lot of roads and there’s a lot of cars on those roads.

Do electric cars really make sense for this problem? And I know you’re doing some things to try to get electric cars into the hands of more people. Or, not really in the hands. In the possession of more people.

Sharon Chinthrajah: Yeah. So it’s not me, you know. The California Air Resources Board and Bay Area Quality Management are trying to make it possible for electric vehicles to be affordable for all communities. And to answer your question about do electric vehicles make a difference, yes.

Russ Altman: Okay.

Sharon Chinthrajah: It reduces our air pollution because of the tailpipe emissions. It’s a little bit of a tricky question it depends on where the electricity is generated from. 85% of our electricity is generated from fossil fuel combustion. So if we can improve the generation of electricity by using solar, wind, and water —

Russ Altman: Right

Sharon Chinthrajah: — energy sources then this becomes an even better solution.

Russ Altman: But even as it is now, an electric car would be a vast on a per person basis if I went out to buy an electric car my emissions would be cut? do we have any numbers about if I’m driving around my Volvo or my Chevy what is the reduction if I turn it into an electric car? Do we know that?

Sharon Chinthrajah: I think that there are some estimates out there I don’t know it off the top of my head. But I know that California has estimated the number of dollars spent on air pollution and kind of introducing these measures

Russ Altman: Yeah.

Sharon Chinthrajah: to make it more affordable. And we’re talking on the billion-dollar range. Because by reducing air pollution and tailpipe emissions and greenhouse gases. We’re reducing healthcare costs that’s transmitting into emergency room visits, hospitalizations for the exacerbation of the underlying medical condition.

Russ Altman: So there’s all the ripple effects. It’s not just about the saved carbon footprint from the combustion, but there’s all those secondary effects of the costs for healthcare, jobs, people being out from work. And all of these.

Sharon Chinthrajah: Exactly.

Russ Altman: This is The Future of Everything I’m Russ Altman more with Sharon Chinthrajah about air pollution, combustion, and what we can do to protect our health next on SiriusXM Insight 121.

Welcome back to The Future of Everything I’m Russ Altman I’m speaking with Sharon Chinthrajah about pollution, combustion, and health. Sharon, one of the things I wanted to definitely ask you about is, you’ve written and talked about the disparate impacts of pollution. It’s not that it affects everybody equally there are certain groups more affected and perhaps, therefore deserving a little more help in addressing the issues of pollution exposure and health consequences. Can you tell me a little bit about what groups we’re talking about and what are the kind of things they can do and we can help them do?

Russ Altman: Yeah thank you for highlighting this. This is so important. You know, people of low income and color really live in these areas with poor air quality. Because they tend to live in areas that are farther away from work, areas that are closer to highways and freeways. And feel the effects of air pollution from transportation. More so than other families.

I have families coming from the central valley, 2–3 hours away to my clinic to seek care for their asthma. And you know, they tend to suffer from more respiratory conditions as well. It’s known that low income, low socio and economic families, people of color tend to have more asthma. And this may be because they live in these areas where they are exposed to more air pollution from birth.

Russ Altman: Yes.

Sharon Chinthrajah: And so have a lifetime of more exposure to air pollution that as they are developing their lungs that’s how they are being exposed.

Russ Altman: And so presumably, it’s in response to that kind of realization that, we mentioned it briefly in the previous segment Clean Cars for All, which is a program that’s actually trying to get electric cars into the hands of folks who might not a) be thinking about electric cars because it’s just not on their radar and it doesn’t seem important. And b) once they do think about it they might say whoa that car is too expensive especially given my lifestyle and what I need to get around or haul around. Tell me a little bit about that program. And how it’s been set up. Are there any initial indicators of success, failure, what are the challenges?

Sharon Chinthrajah: Yeah. So I’m really excited. This, I think, is very forward-thinking of the state of California. That the Bay Area Quality Management Department is offering subsidized money to these low-income families to be able to purchase low emission vehicles like electric vehicles. So currently they have a $9,500 subsidy.

Russ Altman: That’s a pretty significant number.

Sharon Chinthrajah: Exactly. And when you combine that with Federal Rebates of up to $7,500 and State Rebates if they continue up to $2,500. We’re looking at about $15,000-$20,000 toward the purchase and maybe even the lease of an electric vehicle. Which is great, you know. To be able to offer to these people with socio-economic difficulties.

Russ Altman: So this is the first I heard of this program. Tell me a little bit more about it. How long has it been in place? And what’s the uptake been? Is it a wild success? Are there strings attached that make it less attractive for some people? It seems great. Because it sounds to me like half or more of the cost of a car either rebated or subsidized.

Sharon Chinthrajah: Yes. And so this is something that’s new for this year. And the goal is to make it more widely available across California by the end of this year. I think that it’s been successful but, I don’t have the exact numbers for you as to whether or not it’s getting into the hands of the people who need it the most.

Russ Altman: Because it’s a new program?

Sharon Chinthrajah: Yeah.

Russ Altman: And my understanding is that experts like you were advisors to the state as they were deciding whether or not this would be a benefit. Am I getting that right?

Sharon Chinthrajah: Yeah I mean, the California Air Resource Board has many members and advocates really for clean air and reducing emissions and setting standards within California to reduce our carbon footprint and hopefully reduce the effects on global warming, essentially.

Russ Altman: Yes. This is The Future of Everything I’m Russ Altman I’m speaking with Sharon Chinthrajah about well right now, this amazing Californian program to gives rebates and incentives for electric cars. So presumably people can Google this and find out about what the eligibility criteria are and which cars would qualify, I guess matters.

Sharon Chinthrajah: Exactly.

Russ Altman: I’m sure that the 100% electric cars are probably eligible. But it would be interesting to know, for example, these hybrid vehicles are also eligible. Do you have any insight about that? I know this is in the details but —

Sharon Chinthrajah: Yes, and so you can go online and there’s a nice little table often times it’s synonymous with the ones that the cars that actually qualify for the carpool sticker as well.

Russ Altman: Ah.

Sharon Chinthrajah: And you’re right. There are electric vehicles that qualify. There’s also plug-in hybrids particular ones that qualify for this program.

Russ Altman: So there’s a program which could be part,and this gets me to the next area I want to talk about, part of an overall strategy for an individual or a family to reduce their carbon footprint. I mean it’s a feel-good activity but, it sounds like from your initial comments. It’s not really optional it’s kind of mandatory that we all start thinking this way. Can you kind of, as a physician and as somebody who cares about the public health, can you give me a sense of where people have the greatest opportunity for reducing their carbon footprint? And how this can especially help in your practice of seeing fewer people with asthma.

Sharon Chinthrajah: Yes, these are great questions. So it seems like an overwhelming, daunting task, right? But I think we each have to take ownership of what we can do to reduce our own carbon footprint. And then lobby within our local organizations to create practices that are sustainable.

Russ Altman: And I’m sure we also have to have an educational component so that the young people get this, from birth basically.

Sharon Chinthrajah: Exactly, exactly. What you do matters. And so there are simple things you know, like reducing your transportation burden. Because as we talked about that’s a huge contribution to air pollution. And so that includes, purchasing or leasing zero-emissions vehicles. And sometimes that’s electric vehicles, that might be hydrogen-fueled vehicles that we are seeing more in the Bay Area.

Russ Altman: Yes, yes. And I know that’s a challenge because of the economics of housing, it’s a very interactive problem. So people would love to be able to walk to work. But in some areas of the world, the housing costs are prohibitive, and this causes people to have to live two hours away. So these, once again very intertwined social challenges.

Sharon Chinthrajah: Absolutely. And then sometimes just inquiring within your organization of work whether they offer carpool incentives or programs they can hook you up with people who live in your area or they have shuttles to get you to work. Whether or not you can bike or use public transportation whenever necessary particularly on spare the air days.

Russ Altman: Yes.

Sharon Chinthrajah: And then thinking about other ways that you can decrease your carbon footprint. So transportation is a big one you know cars, trucks, that’s big but also airplanes. So you know thinking about taking a local vacation instead of something across the world.

Russ Altman: So that’s a significant contributor as well?

Sharon Chinthrajah: Yes.

Russ Altman: The airplane? Air flight.

Sharon Chinthrajah: Yes And sometimes it’s not possible you know. Due to work, or family that you’re going to do that but where you can be mindful and cognizant of where you are creating emissions and how you can choose alternatives I think is important. You mentioned food waste. So being careful about what you’re buying, buying the right amount of food and using up the food adequately or storing it for longer use. Also turning out the lights and unplugging things at home when you’re not using them. Being mindful of your consumption of energy is also important.

Russ Altman: And all of this will lead to less asthma.

Sharon Chinthrajah: That’s the hope.

Russ Altman: So thank you for listening to The Future of Everything, I’m Russ Altman. If you missed any of this episode listen anytime on-demand with the SiriusXM app.


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