Air pollution does not affect all races equally according to a new University of Minnesota study. The researchers found that nitrogen dioxide (NO2) exposure is a bigger pollution problem for American minorities than for whites.
Nitrogen dioxide is emitted by motor vehicles and by power plants. Exposure to high levels of NO2 can trigger asthma and lead to heart disease. It is one of the seven pollutants routinely monitored by the Environmental Protection Agency.
The study examined urban areas around the country and compared areas in those cities the U.S. Census Bureau labeled “white” with “nonwhite” areas. Overall, the study revealed that nonwhites are exposed to 38 percent more air pollution.
Income also matters, but not as much as race. The study revealed that, on average, a majority of low-income nonwhites had more pollution exposure than did higher-income whites. Low-income people inhale 10 percent more NO2 than everybody else. Poor white Americans breathe 27 percent more NO2 than wealthy Americans.
The big finding in this study is that non-white people inhale 38 percent more air pollution that whites. This disparity in exposure is dramatic enough that, if eliminated, 7,000 fewer deaths from disease would result, the study estimates. In other words, there is evidence that pollution is a bigger problem for American minorities than for whites.
The study also revealed regional differences in the gap between white and nonwhite exposure to pollution. Pennsylvania, New York and Illinois have the largest exposure gaps.
The gap also varies somewhat with region. An urban area, as defined by the Census Bureau, can extend across state lines. The urban areas with the highest racial disparity in exposure are New York-New Jersey, NY-NJ-CT; Philadelphia, PA-DE-NJ-MD; Bridgeport-Stamford CT-NY; Boston, MA-NH-RI and Providence RI-MA.
This study is the first to combine maps, EPA data and satellite observations to investigate differential exposure to pollution. The authors used an air pollution map overlain by Census data, such as income, education and racial composition.
Lara Clark, co-author of the study and a Doctoral student in the College of Science and Engineering stated that the findings would be of interest to researchers, policy makers and city planners. The logical next steps, she said, would be to investigate why the disparity exists and what can be done about it.
The study appears in the electronic journal PLoS One. Aside from race, the study looked at differences by income, education and other factors throughout the country, said the lead researcher, Julian Marshall. Marshall is an associate professor of civil engineering at the University of Minnesota.
Income also had some association with NO2 exposure. The study found that NO2 exposure is higher for low-income people and for those with less than a high-school education.
The race, education, and income disparities may come down to political power, according to Daniel Faber, Director of the Northeastern Environmental Justice Research Collaborative at Northeastern University. He stated that communities with the least political power tend to be targeted as sites for environmentally hazardous facilities.
Faber cited two processes that contribute to the racial gap in NO2 exposure. First, energy companies tend to choose low-income communities, often communities of color, to cite hazardous operations. Second, when a power plant moves into town property values drop and whites tend to leave. The two processes tend to reinforce each other.
The University of Minnesota study shows a disparity in exposure to pollution where the poor, the less educated, and minorities are more at risk. The results build on other social research that shows air pollution is a bigger problem for American minorities than for whites.
By Chester Davis