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Walker Morris

While the article "The impact of exposure to air pollution on cognitive performance" certainly provides important insight on a pertinent issue in environmental economics (the effects of air pollution on the cognitive skills of the elderly), the article made me more concerned about a separate issue regarding the economy of China. This issue is the retirement savings options for the citizens of China. After doing further research on retirement planning in China, I learned that Chinese citizens have far fewer options than Americans. The brief article in the link below provided quite a bit of insight into this. Obviously Americans have several options for retirement planning including social security, 401(k)'s, IRA's, and Roth IRA's. While many retirees in the United States struggle with having enough money, the issue in China seems much more serious. Being a nation with heavy government control, China obviously has a comprehensive government-run retirement system comparable to social security in the United States. However, with a much larger population, the Chinese government system has many constituents to support. Furthermore, as the Chinese economy becomes freer and freer, private retirement options comparable to American 401(K)'s and IRA's have emerged. This has left many Chinese citizens confused with how to retire as new saving options emerge and the structure economy continues to change. Furthermore, many private Chinese companies are hesitant to provide retirement savings plans for employees due to bureaucratic concerns and minimal government subsidies for providing these plans. This makes millions of individuals reliant on the Chinese equivalent to Social Security, a measure that may not be fiscally sustainable as the age of China's population rises in the long-run. As the article by Xin Zhang, Xi Chen, and Xiaobo Zhang reveals, the decision-making skills of many elderly Chinese individuals are diminished by air pollution throughout the country. This is even more concerning as millions of individuals may not be managing their money responsibly due to mental issues caused by pollution and a lack of transparency with the retirement options available to them. This could jeopardize entire generations as they may not responsibly prepare for retirement and may spend their savings recklessly due to mental impairments. The issue reveals how both pollution and poor government policy can jeopardize the savings of ordinary citizens. What the Chinese government should do is reform their retirement system to make private, company based plans more accessible to the public and launch a campaign to raise awareness for these programs. While this has no influence over reducing air pollution in China, it will ensure that millions of individuals can retire comfortably due to accumulated retirement savings. To include environmental concerns, another policy could include additional government dividends or tax exemptions regarded to those who provide sufficient evidence of environmental consideration. This could include a small dividend for those who recycle a certain amount of waste every year, or a tax exemption to business owners who make efforts to make their businesses more environmentally sustainable.

Link: https://nolasia.net/retirement-options-in-china/

Joey Dunn

Although we often discuss the many negative externalities associated with air pollution, the issues presented in the first and second articles particularly grabbed my attention. The first article caught my eye because I had not even considered the potential effects that air pollution may have on cognitive ability and development. The second article stood out simply because of the magnitude of how many people die and are affected by health problems stemming from air pollution every year. Unfortunately, both the cognitive and health problems caused by air pollution are likely to disproportionately affect low-income and disadvantaged communities. This is because poorer communities are much more likely to be situated in areas where air pollution is worse (i.e. next to a highway or near a factory). This serves as yet another example of how environmental issues often align with human rights issues.


After reading the Nel paper outlining the negative effects if air pollution and air particles on health and cellular processes, I was quite astonished by the dangers posed by such emissions. It seems like the most dangerous aspect of particulate matter seems to be the direct inhalation of ultra-fine particles which little is extensively known. Perhaps more concerning is the lack of any kind of regulation for these, the most harmful by products of fossil fuel combustion. I was interested to see how air quality has faired historically in some US cities. I decided to choose NYC as a test case as I live in southwest CT and visit NYC often. I used the air quality index (AQI) to compare the number of days that were unhealth and very unhealthy in 1980, the first year data is available to now. In 1980 NYC has 45 days unhealthy and 45 days very unhealthy. Interestingly, they has now good days. In 200 NYC had 56 good days and only 14 day unhealthy and 4 days very unhealthy. In 2018 NYC had 156 good days, 2 unhealthy, and only one very unhealthy. LA, notorious for horrible air quality, in 1980 had only 6 good days, 47 unhealthy days, and 159 very unhealthy days. Almost half the year in 1980 the air was considered very unhealthy to breathe which is quite unfathomable. In 2000, LA had 27 good days and 56 unhealthy and 10 very unhealthy days. In 2018 LA had 35 good days, 19 unhealthy and 1 very unhealthy days. In both of these examples we can see that by the AQI classification, which measures levels of 03, PM2.5, PM10, CO, SO2, and NO2 to determine a score out of 500 which is then classified into 6 different levels from good to hazardous. While on the surface it seems that air quality in America’s two biggest cities have improved tremendously, which they undoubtably have thanks to more efficient and clean vehicles, less use of coal fired utilities, and other air quality regulations, it can be misleading because the AQI does not quantity the presence of PMs smaller than 2.5 in its score. I would be very interested to see historic measurements of fine and ultra fine PM in US cities. I did see in my research that the EU implemented a first ever a cap on particle numbers to limit the ultra fine particles that are in the air. The regulation hopes to ensure diesel particulate filters are used on all diesel vehicles, which emit most of the UFPM. In a 2018 report on air pollution and child health (https://www.who.int/ceh/publications/air-pollution-child-health/en/) the WHO found that in 2013 ambient air pollution alone costs the global economy $5 trillion a year in total welfare loss. More troubling was that 93% of children worldwide live in environments with air pollution levels above the WHO guidelines. It is truly astonishing how poor global air quality standards are and how detrimental the effect of these unseen killers and inhibiters are. I was also interested in how asthma rates have changed in a country like China which has seen modernization and urbanization at an unprecedented rate in the past 20-30 years. According to a study conducted in Shanghai published in 2015 (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0121577), childhood asthma rates have increased from 1.79% in 1990 to 10.2% in 2011 marking a 470% increase in 21 years. These numbers speak to the dire condition many of children around the world in developing nations. Looking back to the US in 2018 childhood asthma rates were 7.5% while rates for white children where 7.6% while black was 10.6%. I’m not entirely sure why black children have 3% higher rate of asthma but I would predict it is related to what we have spoken about before in relation to living in lower-income urban neighborhoods located near industry with high exposure to polluted air.

Ginny Johnson

I am particularly interested in the finding from the Zhang et. al. article that the negative effect of air pollution on cognitive behavior affects men more so than women. It is interesting that this gendered effect becomes more pronounced the older the subjects are, as well as that there is such a difference in the gender divide between those with primary school education or less and those with middle school or more. I’m curious how much of this gender divide is biological and how much is caused by social forces. Does the divide increase as subjects get older because they are being exposed to more air pollutants or because they were exposed to different social climates when they were young? Or some combination thereof?


“The impact of exposure to air pollution on cognitive performance” by Xin Zhang, Xi Chen, and Xiaobo Zhang highlight the severity of air pollution’s effects on populations specifically the elderly. The attempt to conduct a longitudinal and spatial study was a valiant effort. I appreciate the fact that this article included the fact that older cohorts in addition to being especially physically vulnerable to air pollution exposure are simultaneously responsible for large amounts of money and how to best allocate their funds. Considering that if something as trivial as verbal and math survey questions collected results that changed what are referred to as “complex high-stake economic decisions” also are inclined to be responsive to threats of air quality.
The CFPS seems to be similar to the American Community Survey conducted annually and said to be representative of one percent of the national population.
The interpretation of the empirical data suggests that reducing particulate matter could essentially reverse the declining average scores on the verbal and math test scores. This contradicts my initial assumption that the effects of climate change are completely irreversible.

Didi Pace

A W&L alum who studied abroad in China in the fall term of 2017 said that pollution masks are just a part of daily life there. She ran on the treadmill everyday because the pollution outside was so bad. While she was aware of the physical health impacts of pollution, I am sure her, as well as most, are not as aware of the cognitive effects.

Particulate matter not only has negative impacts on human health, but also affects Earth's climate. Climate change and air pollution are interlinked. As the 2nd article outlined, while there are natural causes of particulate matter (volcanic eruptions, tornadoes/hurricanes, forest fires, sea spray), man exacerbates the problem (vehicle exhaust, road dust, smokestacks).

In Professor Greer's climate change class, we discussed particulate matter's impact on glaciers. The particulate matter falls onto the snow and lowers its albedo, which is the amount radiation reflected back from the surface. This makes sense because the white snow reflects radiation well, while the black particulate layer on the snow absorbs the heat. This heat absorption is causing the glaciers to melt at increasing rates.

Since we are already seeing human health impacts, as well as climate impacts, it would seem as though policy action on air pollution would be more pressing than usual.


These papers were very disturbing, but not necessarily surprising. The "Air Pollution-Related Illness" paper reminded me of the full cost cycle of coal paper that we read last week in the sense that it seems very obvious from a logical standpoint. In the last paper, it seems so obvious that using explosives to blow the tops off mountains creates negative externalities for the environment. In the same way, it seems obvious that breathing in PM from combustion has negative affects on human health. No person in their right mind would want to spend any amount of time breathing in exhaust from a car, because even in the absence of statistical evidence any reasonable person realizes that it can't be good for their health. So in the case of urban areas, its obvious that the air quality is going to be far worse than in an area without cars.

I was in Boston a couple weeks ago, and just walking on the streets it's so obvious that I would rather breath in the air in Lexington than in Boston. Even without understanding how exactly the PM interacts with my lungs and body.

With that said, I was once again very impressed that the paper was able to turn my "hunch" into clear evidence by using data, biology, and chemistry. Though this paper was a little over my head at points, the thoroughness cannot be denied.

The paper on cognitive performance on the other hand is something I had not thought about, but absolutely makes sense. Once again the use of data and statistics was absolutely crucial and impressive.

I'm moving to Boston in August for at least a couple of years and honestly these papers worry me. Even when I was in Boston a couple weeks ago it really hit me that I am going to be sacrificing my health in some form in order to enjoy a modern urban lifestyle. Personally, this is a tradeoff I am more than willing to accept, but it is also something that I will be very aware of every day as I walk to work. My cost benefit analysis of the decision is that the benefits of living in such a unique marvel of humanity is worth the negative health risks. However, its worrisome that the health risks are not all understood and therefore the cost to my health is likely higher than I am accounting for.

Natalie Burden

Reading “The impact of exposure to air pollution on cognitive performance” paper, it struck me about the health care and caregiving costs from dementia. A couple years ago my cousins-once-removed were dealing with both their mother and father suffering from dementia of some form. Meanwhile, they were both also raising young kids. It was a massive economic burden for them as they were paying for medical aid and spending much of their time looking after their parents. It was both interesting and frustrating to think about whether exposure to air pollution could have exacerbated their deterioration in their old age. Both from an emotional and economic standpoint, the thought that air pollution exposure could have caused or worsened the situation is infuriating. Aside from dementia, the cognitive damages that air pollution evidently causes impedes education and decision-making abilities, another issue that has economic implications: as people age, they will be less likely to make good decisions in their jobs. As my job search has been getting into full swing, I have been realizing how much I rely on my cognitive abilities, and if they were diminished by something out of my control (which they probably will be because I can’t escape air pollution), I would be furious.

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