Distribution of Airborne Industrial Toxic Pollution in the United States: Dynamic Spatial Analysis of Environmental Inequality

EPA Grant Number: FP917118
Title: Distribution of Airborne Industrial Toxic Pollution in the United States: Dynamic Spatial Analysis of Environmental Inequality
Investigators: Chang, Grace Hwai-Yen
Institution: University of Massachusetts - Amherst
EPA Project Officer: Michaud, Jayne
Project Period: August 1, 2010 through July 31, 2013
Project Amount: $111,000
RFA: STAR Graduate Fellowships (2010) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Human Health: Risk Assessment and Decision Making


This project investigates the social, temporal, and geographic structure of exposure to industrial toxic air releases in the United States, focusing on the potential health risks affecting low-income communities and people of color. It examines how the relationship between population characteristics (income and race/ethnicity) and pollution exposure varies across time, geographic region, and industrial sector. The study will provide an empirical test of the effects of social, political, and economic features of a region—income inequality, voter participation, and residential segregation—on the relationship between income/race/ethnicity and toxic exposure, and similarly for industrial sector characteristics such as energy intensity and firm concentration.


Exposure to industrial toxic air pollution poses serious health risks in the United States. Environmental justice research has shown that low-income communities of color experience a greater share of the total human health risk from exposure, compared to their population share. This project is a statistical investigation of the relationship between the income and race/ethnicity of residents and their exposure to toxic air pollution, examining how it varies across geographic regions and industrial sectors.


The project will apply descriptive and multivariate methods, using socioeconomic data on neighborhoods from the 1990 and 2000 Censuses of Population and Housing and a unique, new dataset from the Risk-Screening Environmental Indicators (RSEI) project of the U.S. Environmental Protection Agency that provides highly detailed geographic data on exposure to industrial toxic air releases. These data cover the entire United States and are available annually from 1988 through 2006. The correlations between demographics and exposure will be mapped before investigating how these vary across time, region, and industrial sector.

Expected Results:

Environmental justice researchers have offered many explanations for why pollution burdens may fall disproportionately on low-income and minority communities, an important subset of which focuses on imbalances in resources, representation, and political clout. Housing discrimination is an additional barrier that racial and ethnic minorities may face; even when they might have incomes comparable to whites who have the financial means to move into environmentally cleaner neighborhoods, they may be constrained by housing discrimination, thus forcing them to remain in their currently polluted neighborhoods. It is expected that regions with high degrees of economic and political inequality have steeper gradients between socioeconomic attributes and pollution exposure (positive for race/ethnicity and negative for income). Further, regions with high degrees of racial/ethnic segregation would be expected to have steeper gradients between race/ethnicity and exposure to pollution. With respect to industrial sector characteristics, it is possible that high-visibility industries like electric power may face greater pressure to locate facilities away from politically influential constituencies. Conversely, firms in industries with high concentration ratios may be more sensitive to potential damage to their image from environmental inequities because they may attract more public scrutiny. The net effects will be determined empirically, but it is expected that industries with high degrees of energy intensity have steeper gradients between socioeconomic attributes and pollution exposure (positive for race/ethnicity and negative for income), while industries with higher concentration ratios have shallower gradients.

Potential to Further Environmental/Human Health Protection:

The project will make a contribution to scientific knowledge and social progress in several important ways. First, the research will help improve our understanding of the dynamics of neighborhood environmental inequality, with broader impacts in the fields of environmental justice, community health, and public policy. Second, the findings will be of direct relevance to shareholders and other stakeholders in corporate environmental performance. Third, in addition to seeking publication in scholarly journals, the results will be disseminated in the form of public presentations and popular publications that should be of interest to scholars and activists alike.

Supplemental Keywords:

environmental justice, environmental inequality, industrial air toxics, corporate environmental performance, RSEI, race, income,

Progress and Final Reports:

  • 2011
  • 2012
  • Final