NO2 Exposure Disparities By Race-Ethnicity Decreased From 2000 to 2010

A new National Institutes of Health (NIH) funded study examines disparities in exposure to air pollution by race-ethnicity and by socioeconomic status, including the impacts of declining transportation-related air pollutant emissions. The new study was designed to estimate changes over time (2000 to 2010) in disparities in exposure to outdoor concentrations of a transportation-related air pollutant, nitrogen dioxide (NO2), in the United States.

Previous U.S.-based air pollution environmental justice studies have focused on exposure to industrial air pollution or proximity to polluting industrial facilities. Those studies found that exposures decreased for all race-ethnicity groups over time, but that African Americans remained more exposed than whites and Hispanics "by a factor of ∼50%”, according to authors of the new study.

The new study found that estimated annual average NO2 concentrations decreased during the 2000-2010 periodfor all of the race-ethnicity and socioeconomic status groups. Even though the national nonwhite–white mean NO2 concentration disparity decreased from a difference of 5.0 ppb in 2000 to 2.9 ppb in 2010, estimated mean NO2 concentrations remained 37% higher for nonwhites than whites in 2010 (40% higher in 2000), relative NO2 exposure disparities persisted. There were higher NO2 concentrations for nonwhites than whites in 2010.

The study is available at: https://ehp.niehs.nih.gov/wp-content/uploads/2017/09/EHP959.alt_.pdf