Doctor of Philosophy
This dissertation explores the effects of environmental factors on adult’s health and infant’s health at birth. The first chapter of this dissertation studies the impact of maternal stress triggered by wildfire on infant birth outcomes. As a common natural event, one of the most noticeable effects of wildfires is the stress caused by their threat to people’s life and property. This study estimates the impact of exposure to wildfire events during pregnancy, especially the effects of maternal stress triggered by wildfire outbreaks, on infant birth outcomes. By linking three data sources – birth records from the New Jersey State Department of Health (2004-2012), wildfire events data from the New Jersey Hazard Mitigation Plan (2003-2012), and air pollution data from the Environmental Protection Agency (EPA, 2003-2012) – I am able to disentangle the impact of maternal stress triggered by wildfire outbreaks from the impact of air pollution caused by wildfire smoke on birth outcomes, especially birth weight. The results suggest that being exposed to a significant wildfire event would reduce an infant’s birth weight by approximately 39 grams on average. That effect persists after ruling out the possible impacts of air pollution from wildfire smoke. When I estimate the impact of maternal stress triggered by wildfire outbreaks at different pregnancy stages, I find that the adverse effects of prenatal exposure to wildfires are more significant and more dangerous at the early stage (especially the first trimester) of pregnancy. The second chapter of this dissertation investigates how the access to restaurants (fast-food and full-service restaurants) affect the probability of mothers gaining excessive maternal weight during pregnancy, and how would excessive maternal weight gain affect infant’s birth outcomes. Using the Linked Patient Discharge Data and Birth Cohort File (2007-2010) together with the County Business Patterns Data, I first estimate the effects of access to restaurants (both fast-food and full-service restaurants) on infant health at birth. Based on the adverse effects of fast-food restaurants on infant birth outcomes I have observed, I further test whether excessive maternal weight gain is the channel, through which access to fast-food restaurants cause the adverse effects on infant health. The estimation results confirm that the ease of restaurant availability (measured by the number of fast-food restaurants in residential areas) is the factor that causes mothers to gain excessive maternal weight gain and therefore cause the negative effects on infant health (i.e. C-section rate, complications at delivery, and Apgar scores). In addition, I also find that increasing the establishment of full-service restaurants and stores that provide more options of healthier food might help to mitigate the effects cause by increasing fast-food restaurants. In the third chapter, I use the data collected from tweeter accounts to estimate how air pollution could affect people’s emotion. Substantial economic growth is the challenge every economy is facing, part of which requires keeping economic development without scarifying environment. Air pollution, as a side effect caused by fast economic development, is the problem waiting to be solved not only in developing countries but also in developed countries. It is widely approved that air pollution can cause negative impact on physical health in both epidemiology and economics studies. However, the effects of air pollution on mental health are much less studied in economics for the causation. Using the data collected from tweets posted through tweeter accounts, I use a relatively large and representative sample in our analysis. Applying the Linguistic Inquiry and Word Count (LIWC) method. We have constructed an emotion score based on the contains of each tweet, which can reflect people’s mental health status. The estimation looks at the effects of different pollutants on people’s emotion (both positive and negative emotions). We have found that increased concentration level of sulfur dioxide or particulate matters can cause significant adverse effect on positive emotion and the polarity value (i.e. the spread between positive and negative emotion scores).
Zeng, Li, "The Effects of Environmental Factors on Maternal Health, Infant Health and Mental Health" (2019). Theses and Dissertations. 4377.