Long Term Impacts and Policy Implications

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Bonus issued as n withdrawable bonus bets, which expiire seven days after receipt restrictions applies, see full terms at fan dou dot com slash sportsook Gambling problem call one eight hundred gambler or one eight hundred My reset Have you ever considered surrounding your house with a moat to keep it safe Would you hire a professional wrestler as a bodyguard for your car Okay, maybe you wouldn't go that far But if you'd go to great lengths to avoid dealing with your insurance company, You might have insoranoia And if you have insuranoia, you should have NJM insurance They go to great lengths to do what's best for their policyholders Start relieving your insure anoia today at njM. com It's Steven Dner. We recently got an email from a listener who wondered if the recent wildfires in the southeastern United States were going to affect the final exam scores for high school and college students. Not because students were displaced by the fires, but because the wildfire' smoke might have affected their brains This listener had apparently heard an episode we made a few years ago called This is Your Brain on Pollution. So we've decided to replay that episode for you today with updated facts and figures. As for whether this year's test scores in the Southeast were affected That sounds like an excellent research question for an enterprising investigator. If anyone out there decides to do that research, Let us know. We're at radio at freconomics d. comot As always, thanks for listening It's worse than cigarette smoking. it's worse than wars, it's worse than auto accidents What's worse than wars and car crashes and smoking I'll give you hint Imagine you were getting ready to leave your house for work, or school, maybe to go for a run There is some standard information that most of us seek out before leaving home. There's this. We've got partly sunny skies. It's eighty five. South winds at fourteen And there's this about multiple accidentents stalled vehicles causing major delays It makes sense to check the weather and traffic before leaving home, but There's information we don't usually check that could be just as important, if not more so What if this is what you heard in the morning The level of particulate matter in the air today is above the recommended World Health Organization guidelines O even this If your child has an important test today, or you're giving a big presentation at work, you might want to consider rescheduling or even this. The Supreme Court will be delaying oral arguments until next week because of a high particulate matter count in Washington, DC It's well established that air pollution has significant negative effects on the human body, and many places do require a public announcement when pollution levels are high. But is it possible that on a given day, high pollution can affect your brain, your cognitive abilities? So I can't say I've heard many more theories that would surprise me more if they were true Today on Freakakingonomics Radi This is your brain The top card is written in black The bottom card is written in blue. so I'm going to say yes And this is your brain on pollution It's one of the hardest things I've ever done in my life Oh my god Is pollution making us M stupider. This is Freakonomics Radio, the podcast that explores the hidden side of everything with your host, Stehven Dubner Andrea Lenose is an economist at Deacin University in Australia I'm an environmental economist whichich means that I use data and the tools of economics to understand the causes of environmental problems and to think about policy solutions Air pollution is, of course, a long standing environmental problem, Chemicals like ozone and carbon monoxide, and also what's called particulate matter, or PM two point five Tiny little particles in the air that are a diameter that is less than two point five micrometers. so it's more than a hundred times thinner than a human hair And those particles can come from natural sources like dust and smoke, but also from things like the combustion of fossil fuels. So that's one of the most concerning forms of air pollution. Particulate matter can be invisible. so unless it's really bad, you can't tell just by looking at the sky whether the air you're breathing is polluted But the odds are that it is. The World Health Organization estimates that ninety nine percent of people around the world sometimes breathe pouted air The WHO has different guidelines for different pollutants for particulate matter. Anything above five micrograms per cubic meter on average over a year. is considered polluted The average across China is thirty five micrograms The average across the US is nine, still above the WHO threshold, but much better than it was just a few decades ago. Accordingly, our concern about pollution has been falling. In nineteen ninety, fifty eight percent of Americans said they had a great deal of concern about air pollution. Today, that number is only forty percent Here is one of those forty percent I think air pollution is the greatest single threat to human health on the planet. Michael Greenstone is an economist at the University of Chicago, where he directs the Energy Policy Institute and co directs the Climate Impact Lab He also spent a year in the Obama White House working on climate policy. One of his creations is called the AirQuality Life Index The Air quality Life Index uses satellite data to say How much longer would people in any part of the world live if their area was brought into compliance for what air pollution should be? So how does air pollution affect life expectancy The average person on the planet is living two point two years less than if where they lived complied with WHO standards which is what leads Greenstone to say this It's worse than cigarette smoking. it's worse than wars, it's worse than auto accidents The World Health Organization estimates that roughly seven million people die every year from exposure to fine particles in polluted air That's at least double the number of people who died globally from COVID in twenty twenty and more than five times the number of people killed every year in car crashes The more proximate causes of the pollution deaths include pneumonia, stroke, and heart disease. The economic costs of pollution are also massive. One estimate puts it as high as six trillion dollars a year or about five percent of global GDP. Here again is Andrea Lenose. Interest in economics is fundamentally about the productivity impacts And so part of the reason we're interested in cognition is that if cognition affects productivity, then the costs of exposure to air pollution may be much, much larger than we had previously estimated In other words, we know that air pollution is dangerous to our physical health, as evidenced by millions of deaths around the world And as Linz tells us, there are a number of papers that all point in the same direction in that it does appear that there are cognitive impacts of exposure to high levels of air pollution How significant are the cognitive impacts of air pollution The U.S, remember, is a relatively low pollution country, in part because of domestic policies like the Clean Air Act but also because we have offshorered so much of our manufacturing and the pollution that goes with it. study published in the journal Nature in two thousand seven We found that more than fifty percent of China's air pollution at the time was associated with goods and services consumed outside the provinces where they were produced and that eleven percent of Chinese air pollution deaths could be traced to goods and services used in the United States and Western Europe The U S has had the luxury to worry less about the physiological effects of air pollution. Should we worry more about the cognitive effects Be we answer that question, Let's take a look back at how the US got to where it is So the Clean Air Act, I think is one of the most beneficial pieces of legislation that was ever passed Michael Greenstone again It was passed in nineteen seventy, It was President Nixon who signed a cleaner act to law was amended several times Almost always on a bipartisan basis, The Clean Air Act essentially sets limits on the amount of pollution that can be released into the air via manufacturing, transportation, and so on How effective has it been Everyone has probably seen pictures of Delhi today. and there were many parts of the United States that looked like that in the late sixties and early nineteen seventies. But One of my favorite anecdotes from that period is at white color workers in Gary, Indiana, as a regular matter of doing their job brought a second shirt And so These high levels of pollution that we're seeing in other parts of the world, they once exist in the United States And the reason they don't exist in the United States anymore is largely due to the Clean Air Act There are many benefits of cleaner air, even beyond the obvious. A twenty twenty one study in the Journal Environmental Research Letters found that American crop yields are significantly higher than they were twenty years earlier, thanks to fewer pollutants in the air But it also found that some pollutants, especially particulate matter, are still hurting crop yields The central Valley in California remains pretty polluted There's parts of the Midwest that remain pretty polluted relative to the WHO standard. The United States is very clim The majority of the problem is concentrated in Asia especially in India, Bangladesh, China, and in some parts of Sub Saharan Africa. The primary factors that drive pollution in those Asian countries are power generation, home heating transportation and as I mentioned earlier, manufacturing, including a lot of manufacturing that used to be done in places like New York and Chicago and Los Angeles. It's a bit rich for the US to criticize developing countries for their high pollution, especially since most of our environmental regulation came along after we'd built out our infrastructure in cities. Collution is a natural byproduct of civilization building And there's plenty of historical evidence. blackened lungs in mummified tissue from Egypt Peru and Great Britain pointoint to wood fires from ancient homes about air pollution date back at least to ancient Rome when the smokey cloud hanging over the city was called infamous air Heavy heaven. But air pollution really took off with the invention of the steam engine the Industrial Revolution, starting in England. The UK today produces less than three million tons of coal a year, with the goal getting to zero At peak in the early nineteen hundreds, they produced nearly three hundred million tons a year The UK burned so much coal that the natural ecosystem adjusted There's a story of micro evolutionary biology, which is about the peppered moth. I'm not sure if you've ever heard about this Sthan Hbler German economist who teaches at the University of Toronto As for the peppered moth peppered moth appears in the UK in two varieties, a darker and lighter variety. and it's well known that before the industrialization in the North of England, the lighter variety was the predominant species. And this was basically because it could hide on trees from predators But then as cold smoke started turning trees darker We see a rise in the instance of this darker version of the peppered moth. So the darker version of the peppered moth was a byproduct of heavy air pollution kind of like those shirts worn by office workers in Gary, Indiana For Hibblich and his fellow researchers, the moth would be a useful indicator in a much larger story about pollution It's a story that involves geography poverty. win A Westerly wind, to be precise In cities in the western heemisphere, winds blow from the west to the east and you might observe that in a lot of these cities east sides are more deprived deprived meaning lower income There are, of course, exceptions, but the general rule is that the east side of many cities in the western hemisphere are poorer than the west side We started wondering if this was driven by cold smoke during the industrialization and a sorting of poor people into the east Side and rich people away from the east Side And we wanted to understand if this has long lasting effects Collution could have an evolutionary effect on the color of a moth species Could it be that prevailing winds carrying coal smoke could change the demographics of a city Hibblich and his co authors Alex Tru and Janos Zilberg began to assemble data from seventy cities across England, starting before coal was heavily used as a fuel for industrialization and extending through its heyday This was not a simple task and it required a fair amount of creativity. For instance They hunted down the locations of industrial smokeestacks. We started looking into historical maps and found out that Victorian cartographers were absolutely stunning in the level of detail that they drew into their maps we found the exact location of industrial smokkeestacks within factory buildings These factories were the sites of steel production and other processes that burned massive amounts of coal We basically found across all these seventy cities. In England, we found about five thousand chimney locations, like the exact geol locations They were literally like a historical version of Google Maps The researchers also incorporated census data, like baptismal records to get at the economic demographics of the English population But what about pollution data Victor and England may have had brilliant cartographers, but they didn't have monitors to measure particulate matter. This is where the peppered moth comes in handy Using the geolocations of the old smoke stacks to pinpoint the pollution source The researchers used an algorithm to model how that coal smoke was carried eastward on the wind And they confirmed the model's prediction by aligning it with the historical ratio of dark to light peppered moths in a given area, since there were more dark moths in high pollution areas Clever. Yes Piblick and his co authors recently published their findings in a paper called East Side Story, Historical Pollution and Persistent neeighborhood sorting What did they find So after cold smoke came in, we see a resorting of poor households into the eastide. We have data from eighteen seventeen, which is before cold smoke was a main fuel for the industrialization. And we find that in eighteen seventeen, the wind direction where cold smoke would blow to doesn't have an effect Meaning that in eighteen seventeen, before heavy coal use, the east sides of cities were not systematically poorer than the west sides Then they looked at the data from eighteen eighty one. They chose that particular year because they had really good data We had a census where we had All the names and addresses transcribed And because there was by now a lot Pole being burned It's pretty much just before the heydays of your industrialization And what did they see in eighteen eighty one In eighteen eighty one, we see a pronounced pattern where there's a much higher share of low skilled workers on the east side of the city What's your best evidence that this relationship is causal and not just a correlational finding? If you drow let's say a small circle around a chimney, you would expect in general to have a higher instance of low skilled workers, just because commuting at that time was walking and they have to live somewhere close. But even if you hold distance constant and drow a circle, you would then see that as you walked along a circle, once you get to the east, you will see that the instance of low skilled workers is in the range of one or two percentage points higher Are the low skilled workers low skilled because of the coal smoke or are they living there because they're low skilled workers I cannot tell for sure if it's because of the cold smoke. I think in the past it was mostly a sorting into industries. From today's evidence, we know that there might be intergenerational effects and pollution might also have longer lasting effects that might affect cognitive capacities longonger lasting effects that might affect cognitive capacities, that is, effects that outlast the original nineteenth century pollution. The idea is that children who grow up in those polluted areas suffer negative effects that lead to worse outcomes in education, health and income, even if they were to move away later. The UK, like the US, began cracking down on air pollution in the mid twentieth century. Here's the thing Piblick found that the effects of neighborhood sorting didn't go away What we're seeing is that really polluted and really unpolluted neighborhoods, they are basically becoming even more extreme, either richer or poorer. What we're finding is that one standard deviation increase in pollution would lead in the past to about fifteen percent Higher share of low skilled workers in neighborhoods. and today we would see that this would go up to twenty percent The likely explanation is a classic case of path dependence You have the causes initially that the Eastide had these negative effects of pollution, pooor people sorted there. and then the effects were cemented over time by additional investments, right mayaybe you had a highway cutting off the east side from the west side or you have poor building structure. As result of that, you have a certain composition of residents, you have less funding for schools, you have less funding for other amenities and this is then the snowball effect And our paper we find, for instance, test scores in these east sites are lower and that crime instances are higher and Lower test scores and higher crime in the areas that have historically had high pollution But again, how can you untangle cause from effect Does pollution itself lower people's cognitive abilities or do people with lower cognitive abilities sort into polluted areas? Lower cognitive abilities may mean lower incomes, which may mean fewer options when it comes to where you live. And how can you untangle this question in the face of snowball effects like school funding brings us back to Andrea Lenose I had been reading the literature on the effects of air pollution on productivity, but also other behaviourors, for example, crime. And knowing that a leading hypothesis for those effects was really this cognitive impact So there's a literature showing that the test scores of high school students is negatively impacted by exposure to particulate matter But we didn't at that stage have much evidence for the cognitive effects in adults. And that makes sense because we don't regularly sit high school exams every year as adults There was one piece of evidence for the cognitive effects of pollution on adults It came from a paper that analyzed baseball umpires Yeah, who said economics isn't fun. This was researched by James Archmith, Anthony Hayes, and Sude Sabarian They're able to compare quality of Umpres' decisions on days of high pollution exposure and low pollution exposure And they did find that umpires made more mistakes when they were in a place that had a high pollution level on that day That's a really important paper. It demonstrates that there is an impact on performance of really highly skilled professionals. but it is a study of a group of individuals that are probably fairly similar doing one task. An important task for one specific task What the nose wanted to see was the cognitive effect of pollution in a larger population across a diverse array of tasks recently been exposed to some advertising by lumosity and suddenly thought, wow, well there's a company that is claiming to test the cognitive ability of lots of adults across the United States Lens, you may know Lumosity's name from advertising. They've sponsored a lot of radio and podcasts, including ours for a short time in twenty fourteen Limosity is a so called brain game app created by Lumos Labs, a company founded in two thousand five. It now claims more than a hundred million users across nearly two hundred countries Lots of data They have something called the Human Cgnition proroject where researchers can apply to either use their data or to use their platform to undertake other tests Lenose was able to get hold of data from more than one hundred thousand users across the US playing a variety of games over a three year period So we have games that measure verbal ability your attention, your flexibility, so how quickly you can shift from one cognitive task to another, your memory, so this is your very short term working memory, your math ability, your speed, so speed of processing, and then also problem solving There's a lot of controversy over whether lumosity and similar products actually improve cognition. In fact, They paid a two million dollars fine in twenty sixteen for deceptive advertising But that wasn't the question Lenause was interested in. She and her research partner, the economist Edson Seververini We're looking at a different set of questions. They wanted to know whether day to day changes in air pollution in a particular place ed the scores of people who played games on lumosity The World Health Organization recommends that in a twenty four hour period, particulate matter should be below fifteen micrograms per cubic meter. The EPA threshold is higher at thirty five Particulate matter is just one of the many pollutants the EPA tracks across the US rolling up the total into a daily measure called the air quality index or AQI. Edson Svernini, as a researcher interested in air pollution, was already acutely aware of how much variation there can be day to day I always go for my morning walk and I always check on my phone. What is the air quality index for the day? If it's below fifty, you are in a good or green color of the AQI. if it's between fifty and one hundred, it's yellow like the moderate pollution and then Above a hundred is when I avoid leaving to house because that's where It starts getting a little bit unhealthy to be outside Severini teaches at Boston College, but when we originally interviewed him for this episode, he was at Carnegie Mellon University, which is in Pittsburgh, which is historically one of the most polluted places in America. For decades, Pittsburgh was a cradle of coal, iron, and steel production. When Charles Dickens visited in eighteen forty two, he wrote, Pittsburgh is like Birmingham, in England. It certainly has a great quantity of smoke hanging over it Like Gary, Indiana, Pittsburgh was a two shirt town, and it's still rated as the sixteenth worst US metro area for particle pollution That said, not all parts of the Pittsburgh area have the same level of pollution on a given day, and the same goes for all the places that Svvernini and Lenose wanted to measure in their study. Pollution levels are not measured around us, like attached to our bodies. So that would be the ideal experiment. You are breathing the air, you know exactly how much pollution you have in the air. It's not the case. And so that creates noise in the data which would underestimate the relationship between cognitive function and pollution But they did find a way to address that problem We used the wind direction that brings pollution from other locations And that makes a uniform level of pollution for all individuals in an area independently on whether they are close or slightly farther away from the monitor Sverini and Lenose ran their analysis across more than four million lumosity gameplay observations and measured that against pollution data across the U.S What they find The headline result is that there is a cognitive impact for the working age population In other words, it's not just among test taking students We're actually finding that the largest effects are for people under fifty. And not just for baseball, umpires either. So this is an issue for the working age population, and we expect that to have pretty significant productivity impacts The second main result that I think is entirely novel is that it does seem to affect memory ability. And so if we think across occupations, if we think about sectors that rely more on memory ability, we expect to see the productivity impacts in those areas be more significant So what are we to make of this information? What kind of policy implications does it have That's coming up after the break and also Stephven. Hey, Angie. Lvit's here too. Hey Levit Hey, how are you doing Dner I play some lumosity games with my freereconomics friends, Angela Duckworth and Steve Levitt, who are not aware that this is about pollution levels in their respective cities because I want this to be truly cutthroat This is the kind of thing I'm really good at. Like I would honestly say, this is my specialty I'm probably more competitive than MOO How would the climate change conversation be different if instead, we were talking about pollution I'm Stephen Dubner. This is Free Eonomics radio. We'll be right back Enjoy the sunshine with sales on grill ready favorites from Whole Foods Market outs to sizzling New Heights with their marinated salmon and Maid in house marinated beef and chicken, Entertertain with low price three hundred and sixty five brand chips and dips, like hummus and guacamole, and sweeten every party with brown butter chocolate chip cookies. Remember to pack the cooler with probiotic sodas, sparkling waters, and more. Summer savings await you at Whole Foods Market Enjoy even more before you spin with Caesar's Palace Online Casino. Download today and register with Code radio Lunch. ten dollars no deposit casino bonus on seelect sllot games, one time wagering requirement. Plus one hundred percent deposit match up to one thousand dollars on seelect slot games. fifteen times wagering requirement. pllus two thousand five hundred bonus reward credits. Must be twenty one plus and physically present in New Jersey. mininimum wagering within seven days requi tolock bonuses. full terms wagering requirements at Caesarspalace onnline dot com slash promos. if you were someone you know has a gambling problem call one hundred gambler Have you ever considered surrounding your house with a moat to keep it safe Would you hire a professional wrestler as a bodyguard for your car Okay, maybe you wouldn't go that far But if you'd go to great lengths to avoid dealing with your insurance company, You might have insoranoia And if you have insuranoia, you should have NJM insurance They go to great lengths to do what's best for their policyholders Start relieving your insure anoia today at njM. com Angela Duckworth and Steve Leva, you're two the smartest people I know. So I thought we could play some brain games today Are you both feeling relatively sharp Are these the kind of games that one of us is going to win and the other two lose? God The two of you are made for each other because the first thing Levitt said before we started recording was something about What did you say L live it I said, it's no fun to play with Angie because she's been playing these games her whole life because she's a psychologist. and I know zero about psychology. I'll play these games all day long But Leit, you play trivia at least. You love gaming? I do. You know, the problem for me is that one of the few things I have left is the belief that my brain still works And if you take that for me, I'm going to be really upset Would you say there's any external factor that might contribute to a subp performance today? Maybe you didn't sleep well last night. Do want to just pre register your conditions I never sleep while I have way too many kids. That's my standing excuse is that I haven't had a good night's sleep in about eighteen years And, anything you want to register? Well, as you know, I'm a pretty sleeper, but improbably I actually slept fine last night or uncharacteristically, I should say. So there's that. I was going to complain about the time of day, but then again, it's more or less the same time of day for all of us. Yeah, we should say it is late in the day. It's a little after five PM on the east cooast and Levit's in Chicago So that's of the day. So he's got a one hour advantage on this. Can I say my air conditioning is broken and it's really hot? Oh, o can you win, then In case you don't know, Steve Levitt is a prorofessor at Emeritus of Economics at the University of Chicago. He's also my free economics co author, and he hosts a few episodes of this show as well. Angela Duckworth is a psychologist at the University of Pennsylvania in Philadelphia. She's the author of the book Grit, and she and I used to host the No Stupid questestions podcast together Anyway, the three of us set out to play three games as part of Lumosity's fit test One game is said to measure mental flexibility another Memory. Third, called train of thought ed to test our attention by having us guide different colored trains to their respectively colored destinations If all that sounds super easy, You should try it Okay, here we go This is so cute. I love trains. Oh my Godd, this is hard This's one of the hardest things I've ever done in my life Oh my Godd Let's see, I got thirteen thousand five hundred points and I scored better than seventy percent. I don't even want to tell you guys how I did Come on, tell me how you did I was thirty four out of thirty nine ninety seven percent. Wow, Lev it. I just said it was the hardest thing I'd ever done. I didn't say I was messing up. ninety seven percent. Lev it, I'm really impressed. I wonder what strategy you used ninety seven percent wasn't Levit's actual score, it was his percentile ranking for his age group. That's how Lumosity ranks you After playing all three games, the results were in love it was the clear champion with an average percentile rank of ninety two Pret impressive, although I suspect Levitt may have logged in earlier under a pseudonym to practice. He is sneaky like that and very competitive. On the other hand, He's also really smart, so I'm probably wrong Angela, meanwhile, was very consistent across the three different tasks, but her average was lower, seventy first percentle. For what it's worth, my scores were inconsistent, a high memory score, but really low attention, which probably has something to do with Wa I forgot what I was going to say Anyway My average was around the same as Angela's, seventy second percentile. So Angie, how do you feel about your performance on these games today Well, I'm pretty disappointed, Steve. and I like to think of myself as better than a C minus brain, but maybe I'm, you know less smart than I thought I was at least on these games Levt, how do you feel about your performance today You know, I'm relieved because I have the self image that these stupid little games are my fortete. I have to say actually, at the particular moment when we' doing it, I felt great. I don't sleep as much as I would like to, but honestly no, I felt very sharp today I cannot think of a single excuse for not doing well in these games I'm curious if either of you have ever thought about ariculate matter pollution in the atmosphere as a potential contributing factor to cognitive ability What do you mean particulate matter in the atmosphere No, I guess the answer is I haven't thought about that. I don't know what you're talking about On a particular day, governor, you mean like How much is in the air today Yeah, so what would you say if I told you that a couple of economists analyzed lumosity gameplay just like we did in different places and found that Qote, E when air pollution is below EPA and World Health Organization quality guidelines cognition is negatively affected across seven different cognitive domains Furthermore Their identification relies only on short term changes in pollution exposure within an individual's play history Would that surprise you I'm trying to process this. Levin, what do you think So I can't say I've heard many more theories that would surprise me more if they were true. But what do I know about the world So let me read you some numbers. This paper finds negative cognitive effects at just twenty micrograms per cubic meter Now, here's what's interesting. In the three cities where we are, I'm in New York, Angeles in Philadelphia, Levitt's in Chicago Average in twenty nineteen, for instance, New York was the lowest of those three at seven micrograms per cubic meter Philly is at ten point three and Chicago was the worst at twelve point eight How many particulates are there in Chicago today? Okay, so I have some good news and some bad news The good news is Lev, you are suffering very low particulate matter in Chicago today As of today Chicago only had eight point seven micrograms per cubic meter. Philadelphia and New York We have very high levels today, as it turns out. Do we? We have twenty three point four in New York and twenty four point six in Philadelphia. Is there that much variation in particulate matter There is that much variation not only place to place, but day to day. Wow. That's what's really interesting. The day to day part. I didn't realize that. Levitt earlier, you said that you just felt incredibly sharp and focused when it came time to do the tasks. Do you think that had anything to do with the relatively low level of particulate matter in the air in Chicago I wouldn't think so, but maybe I should start tracking it. I could, without knowledge of the partticulates read how I felt each day. So you each sound relatively skeptical of the findings of this paper. Let me just ask for like a confidence level, zero to ten, let's say, that these findings are somewhere in the ballpark of useful and true I want to rate my own confidence in saying anything about somebody's findings before reading their paper. I would say that would be like a one. Okay, fair enough. Levitt, do you want to speculate I would say it feels like a one in terms of likelihood of being true, and if true, a ten in terms of importance After the break, just how bad is this cognitive impairment from air pollution We have probably been underndstating the losses from air pollution by about fifty percent. You're listening to Freeconomics radio. I'm Steven Dubner. We'll be right back Enjoy the sunshine with sales on grill ready favorites from Whole Foods Market Take cookouts to sizzling New Heights, with their marinated salmon and madeaid in house marinated beef and chicken. Entertertain with low price three hundred sixty five brand chips and dips, like hummus and guacamole, and sweeten every party with brown butter chocolate chip cookies. Remember to pack the cooler with probiotic sodas, sparkling waters, and more. Summer savings await you at Whole Foods Market Enjoy even more before you spin with Caesar's Palace Online casino. 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If you or someone you know has a gambling problem call one eight hundred gambler Have you ever considered surrounding your house with a moat to keep it safe Would you hire a professional wrestler as a bodyguard for your car Okay, maybe you wouldn't go that far But if you'd go to great lengths to avoid dealing with your insurance company, You might have insoranoia And if you have insuranoia, you should have NJM insurance They go to great lengths to do what's best for their policyholders Start relieving your insure ania today. at njM. com So what is the likelihood that local real time pollution levels can impair cognitive function in the moment It might help to know the mechanisms by which this could happen I'm not a medical expert. What I'm going say now is based on, you know reviews of this literature A again is Boston College economist Edson Seververnini There are two ways where air pollution could impair cognition. One is that they go directly to the brain and then it affects the functioning of the neurons, but also they stimulate pro inflammatory, I think it's called cytokines. And so this is a more indirect route. But everybody who is doing research on this topic, they always see processes that are affected by pollution, oxidative stress, inflammation, some neuron loss I should note that Angela, Steve, and I played only a few games on one day The data that Svverini and Lenause analyzed was much more robust Still, I asked whether our scores should be adjusted based on that day's pollution levels in our respective locations. The impact of this exposure to pollution would be to shift someone in that ranking by about six points So if you were playing on a day that was above the threshold that we sat and you were performing like in the seventy fifth percentile, on average, you would have been on the eightieth percentile that day And that's just on average. So once you account for the local pollution levels in New York and Philadelphia that day, which were high, And Chicago, which was low Angela and I might be right up there with Levitt The Nose and Seververnini's work was published last year in the journal of the Association of Environmental and Resource Economists There is also research from the economists Michael Gilraan and Angela Zhang, who looked at data from over ten thousand school districts in the US and found that each increase in particulate pollution led to a decrease in student test scores We asked Michael Greenstone, the pollution and policy veteran What he thought of Lenaot' and Svernini's findings. Now do keep in mind that Edson Svernini was actually a postdoc under Greenstone You know, it's a very well done paper You know I know artificial setting long run meaning is a little bit hard to sus out The more challenging thing is you know, to find inststances where there's long run variation I think in both the health and in the cognition literatures, The holy grail is not to rely on studies that use either day to day or month to month But to find a setting where There's like a permanent difference in air pollution. It's much harder to come up with those examples But that is after all what policy is trying to do. It's not trying to reduce pollution on Tuesday. It's trying to reduce pollution three hundred and sixty five days a year Greenstone thinks he may have found the Holy Grail B seeven or eight years ago, I stumbled upon an example from China that seem to mimic this kind of ideal And that's something called the Hauai River winter heating policy It dates back to when China muchuch less Walthy And there just weren't enough resources to provide winter heating for everybody. they did something quite arbitrary and capricious They drew a line across the middle of the country And that line follows the Whaite River Hawai River, by the way, runs west east, not north south And they said, okay, if you live north of that line where it's colder. We're going to install central heating systems And we're going to give you free call So that's in the north. In the south, the policy was Guys, you're out of luck. no heating So what Greenstone was looking at had nothing to do with whether people sorted themselves into neighborhoods on the east or west side of a city. like Stehen Hiblich looked at in England This had to do with comparing the health and educational outcomes of people living on the north side of the river people were warmer in the winter, but exposed to a lot of coal smoke the south side where you might have been colder but didn't have much cold smoke And thanks to Chinese government policy, there was almost no migration from one side of the river to the other Migration was greatly limited. And I thought, wow, this is the thing I've been searching for Greenstone was able to analyze data that included roughly forty thousand people living in urban areas within a five degree latitude range north and south of the river The first outcome he looked at was life expectancy If you were going just to the north of the river Those people, they were the intended beneficiary of this policy. On average, they're living about three years less than people born just to the south And that was such a striking finding at least to me, that I thought, wow, I hadn't realized quite how devastating air pollution was Even though I've been working on it. In subsequent research soon to be released, Greenstone looked at the educational outcome of kids born between nineteen seventy five and nineteen eighty two Here, he's trying to estimate the cognitive effects of coal pollution. Children born just to the north of the Hui River. completed almost one full year ls of education, then kids born just to the south And not just that, we' able to observe them as adults. And on average, they earned about thirteen percent less than children born just to the south I think this is the first large scale evidence on the impacts of long run early childhood exposure at the levels of concentrations that prevail in many parts of Asia and Sub Saharan Africa So How bad is this news? or maybe a better question to ask, just how damaging is the cognitive impact of air pollution We have probably been understating the losses from air pollution by about fifty percent But then some Kind of good news That would imply that the benefits of reducing air pollution are fifty percent larger than we realized and would justify more stringent environmental regulations High polluting countries, especially China have been pushing hard to lower air pollution As recently as twenty thirteen, the particulate matter level in Beijing was over one hundred micrograms per cubic meter Remember, the level over a twenty four hour period recommended by the WHO is under twenty five By twenty eighteen, the average level in Beijing had fallen to just over fifty, and it has continued to fall across the country. And if you take My estimates literally They imply that a child born in twenty eighteen, relative to a child born in twenty thirteen, will live one point four years longer Greenstone says China's trajectory is much more dramatic than ours The United States accomplished nothing like that so quickly after the Cleanerir Act. And as an economist who's done a lot of work on environmental policy, he's been disappointed with the US government's approach to the broader issue of climate change The Clean Air Act was really focused on reducing pollution locally in parts of the country where pollution concentrations were very high CO two is a totally different ball of wax in the sense that It is a global pollutant. The impact of emitting a ton of CO two in Fresno is exactly the same has emitting a ton in Banger Maine. I think the United States is an extraordinary outlier in the international arena in terms of its difficulty in recognizing and developing a coherent strategy for confronting climate change. The United States is the only country in the G seven that does not have a coordinated national climate policy, and that's striking. We called Michael Greenstone to ask what he thinks about the state of environmental regulation under the Trump administration. He pointed us to a recent policy change whereby the ennvironmental Protection aggency will no longer consider the health benefits of reduced pollution in setting clean air regulations