Air Pollution Week 2

Question 1

Main health impact of air pollution

Answer 1

Cardio-pulmonary diseases (heart/lungs)

Question 2

WHO show how many died from all air pollution in 2016 (indoor/outdoor)

Answer 2

7 million

Question 3

Mortality and morbidity from air pollution

Answer 3

Big contributor to mortality

Pollution is also a morbidity burden (not dying, but suffering)

Question 4

Distribution of burden of air pollution across countries and communities

Answer 4

Tends to be in poor countries, and on poorer communities within countries.

Question 5

Health impacts examples on economy (3)

Answer 5

Strain to healthcare, work absence, productivity

Question 6

What are social impacts and examples

Answer 6

Not captured by GDP

E.g people being alive and healthy

Question 7

Measures to account for social impacts (2)

Answer 7

VOSL or QALYs

Question 8

Important: considering causal impact of pollution on health. (Pollution causes ill health, not just a correlation)

Why is it important to establish causation not correlation?

Answer 8

To make policy changes appropriate. Which may be expensive

Question 9

Zhong et al (2017)

Answer 9

Based in China, 4 is unlucky.

Natural experiment:

Limit cars on road by last number on license plate. On days where 4 is restricted, less pollution as people avoid 4 on plates. On other days, more congestion and pollution.

Question 10

Note: we should exploit naturally occurring phenomena

Question 11

Lavaine and Neidell (2013)

Answer 11

Refinery workers in France went on strike- fall in SO2 (sulfur dioxide) emissions.

Compared health outcomes for pregnant women before/after and in close/far proximity from refineries.

Pollution levels fell during strikes, and pregnancy outcomes improved with improved birth weights of babies, stillbirth less likely. 25km within strikes were similar to the far prox

Question 12

What is this method known as?

Answer 12

Differences in differences method.

I.e look at all different variables e.g before strike, after strike, and whether they are close, far from refineries.

Question 13

Moretti and Neidell (2011)

Answer 13

Natural experiment.

Ports in LA and Long Beach contribute to 25% of ozone pollution to city.

Bad seas in Shanghai, means no boats arrive in ports in lA as none arriving from Shanghai.

Question 14

What is this method known as?

Answer 14

Instrumental variables method

I.e sea conditions determine daily arrivals and thus pollution

Question 15

Pollution on productivity: most pollluted country

Answer 15

India

Question 16

Chang et al (2016)

2. Pros (2) and cons (4)of findings

Answer 16

Outdoor air pollution (Particulate Matter (PM2.5)) on productivity at pear-packing factory.

Study association between fruit boxes packed and PM2.5 levels that day. Similar results with call-centres

Cons
Decreased productivity (longer to pack pears)
Reduced wages for workers for performance related pay
This reduced productivity occurs at current air quality standards
Higher environmental regulations slow down production with business closures and job losses, so higher costs for the economy

Pros
Improving air quality=significant increases in productivity
Poor air quality does not affect worker’s decision on hours worked.

Question 17

What was the actual figure found (unit of PM increase leads to… in productivity)

Answer 17

10 unit increase in PM2.5 = 6% fall in productivity

Question 18

Hernstadt et al (2021) (CHICAGO WINDY CITY)

Answer 18

Examined crimes in Chicago by side of interstates.

Causal link between air pollution and aggressive behaviour. More wind… more crime

Question 19

Additional examples

Answer 19

Exposure to air pollution makes rats put on more weight.

Air pollution causes sleeplessness (used weibo more at night)

Air pollution causes worse grades (in Brazil university entrance tests)

Question 20

2 limitations and gaps on studies

1.Why many studies omit a large fraction of total population.

And what does this mean for results? Overestimated or underestimated? And what should be considered?

Answer 20

Many studies are focused on extreme outcomes e.g hospitalisation or mortality. Which typically focuses on elderly, infants or those with health conditions, rather than the working age population.

So pollution effects may have been underestimated.
We should consider subtler daily influences e.g asthma attacks

Question 21

Endogeneity of pollution

Answer 21

As firms increase productivity, they emit more pollutants. Reverse causality.

Question 22

Things to consider also in researching productivity on pollution (3)

Answer 22

Endogeneity of pollution

Changes in natural events can distort productivity e.g weather-so readjust sensitivity to account for these

Evidence in highest-skilled sector, where value added is highest. (Only covered basic manual jobs)