Air Pollution Week 2 Flashcards
Main health impact of air pollution
Cardio-pulmonary diseases (heart/lungs)
WHO show how many died from all air pollution in 2016 (indoor/outdoor)
7 million
Mortality and morbidity from air pollution
Big contributor to mortality
Pollution is also a morbidity burden (not dying, but suffering)
Distribution of burden of air pollution across countries and communities
Tends to be in poor countries, and on poorer communities within countries.
Health impacts examples on economy (3)
Strain to healthcare, work absence, productivity
What are social impacts and examples
Not captured by GDP
E.g people being alive and healthy
Measures to account for social impacts (2)
VOSL or QALYs
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?
To make policy changes appropriate. Which may be expensive
Zhong et al (2017)
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.
Note: we should exploit naturally occurring phenomena
Lavaine and Neidell (2013)
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
What is this method known as?
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.
Moretti and Neidell (2011)
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.
What is this method known as?
Instrumental variables method
I.e sea conditions determine daily arrivals and thus pollution
Pollution on productivity: most pollluted country
India
Chang et al (2016)
- Pros (2) and cons (4)of findings
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.
What was the actual figure found (unit of PM increase leads to… in productivity)
10 unit increase in PM2.5 = 6% fall in productivity
Hernstadt et al (2021) (CHICAGO WINDY CITY)
Examined crimes in Chicago by side of interstates.
Causal link between air pollution and aggressive behaviour. More wind… more crime
Additional examples
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)
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?
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
Endogeneity of pollution
As firms increase productivity, they emit more pollutants. Reverse causality.
Things to consider also in researching productivity on pollution (3)
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)
