Outdoor NO2 Exposure Disparities at Public Schools in the Contiguous United States

Abstract

OPS 60: Social factors and environmental health across the world, Room 210, Floor 2, August 27, 2019, 1:30 PM - 3:00 PM Background/Aim: Average residential exposure to outdoor air pollution is higher for racial/ethnic minorities and low-income households than for non-Hispanic whites and high-income households. Most research on this topic uses Census data to investigate concentrations at location of residence, yet, children spend substantial time in and around schools. Here we aim to assess exposure disparities for nitrogen dioxide (NO2; a traffic-related air pollutant) at all public schools in the contiguous US. Methods: A year-2006 satellite-based land use regression for NO2 was used to estimate outdoor concentrations at all public-school locations (89,420 schools; 48 million students) in the National Center for Education Statistics School Universe Survey (2005-2006). We compare concentrations disparities by race/ethnicity and income (student eligibility for free/reduced lunch) while controlling for level of urbanization. Results: Minority schools (> 50% students are racial/ethnic minorities, i.e., are not “non-Hispanic white”) and low-income schools (> 50% free/reduced lunch eligible students) are more likely to be above the WHO guideline (40 µg/m3) than white-majority schools (20× for all schools; 11× for schools in urbanized areas) and high-income schools (4× for all schools and for schools in urbanized areas), respectively. For large and medium urbanized areas, minority students are exposed to higher concentrations than white students, even when controlling for income. Disparities by income diminish when controlling for race/ethnicity, except for rural locations, where free/reduced lunch eligible students are exposed to lower concentrations than ineligible students. Conclusions: We found large disparities in outdoor NO2 exposure at school locations across the contiguous US for race/ethnicity and to a lesser extent for income. This finding – that race/ethnicity is a larger driver of disparities than income – is consistent with studies evaluating residential outdoor NO2 disparities, and suggest that school exposures could exacerbate disparities, particularly for minority students.