Doctoral Dissertation Research: Segregation and Its Effects on Social Disparities in Exposure to Air Pollution

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

This doctoral dissertation research project will examine how racial and ethnic segregation impacts the unequal exposure to air pollution by considering the full range of spaces individuals experience daily (e.g., home, workplace, and leisure activity locations). The doctoral student will develop an individual-level segregation measure that incorporates this more comprehensive conceptualization of segregation and combine it with a method for assessing personal exposure to air pollution at a high spatiotemporal resolution. This new fine-grained approach will enable investigators to more reliably examine the association between segregation and the disparity in exposure to air pollution because it can improve on several methodological problems in previous studies that were solely residence-based. Moving beyond simplistic understandings based solely on residential segregation, the research findings will yield new insights into how the disparities in environmental exposures are shaped through complex socio-spatial processes and how non-residential segregation contributes to those disparities. The investigators will collaborate with relevant organizations and agencies to disseminate the project findings. Findings will provide more nuanced knowledge for future policy recommendations by emphasizing the need for policies that consider human daily mobility. The findings will also help promote general awareness and understanding of the unfair burdens of air pollution and the urgent need to address such disparities. This new knowledge will contribute to a more inclusive and comprehensive participation in policy-making and engagement in a constructive dialogue about environmental justice and a wider range of social disparity issues stemming from segregation. This project addresses three specific research questions: 1) Do individuals experience different levels of segregation over the course of a day, and if so, do racial minorities experience higher levels of segregation both during the daytime (i.e., in non-residential areas) and at night (i.e., in residential areas) than the majority? 2) Are the average exposure levels of different racial groups different, and if so, which group faces the highest level of exposure to air pollution? 3) How does the observed segregation at different times of day affect the disparity in total daily exposure to air pollution? The first question will be addressed by developing a new segregation measure that considers spatiotemporal proximity among individuals in combination with an activity-travel diary dataset that includes personal characteristics and detailed daily travel information (e.g., geocoded locations and time durations of trips). The differences between time periods will be examined using a repeated-measures analysis of variance (ANOVA). To answer the second question the doctoral student will use a geographic information system (GIS) to integrate exposure level data with diary data, as well as hourly air pollution data produced from air dispersion modeling. An ANOVA will then be conducted to compare the racial differences. The third question will be answered by geo-visualizing the spatial relationship between segregation at different times and differential exposures to air pollution using GIS and by conducting regression analyses on the association. This project will be based in the greater Atlanta, Georgia, region, but will be generating information that will be applicable to many other metropolitan locations in the United States.