Journal Article

Geographic Variations in Urban‐Rural Particulate Matter (PM2.5) Concentrations in the United States, 2010–2019

Eberth, Jan M., Crouch, Elizabeth, Porter, Dwayne E., Kilpatrick, Daniel J., Hung, Peiyin, Cothran, Jeremy, Self, Stella

2024

Overview

Fine particulate matter 2.5 (PM2.5) is a widely studied pollutant with substantial health impacts, yet little is known about the urban‐rural differences across the United States. Trends of PM2.5 in urban and rural census tracts between 2010 and 2019 were assessed alongside sociodemographic characteristics including race/ethnicity, poverty, and age. For 2010, we identified 13,474 rural tracts and 59,065 urban tracts. In 2019, 13,462 were rural and 59,055 urban. Urban tracts had significantly higher PM2.5 concentrations than rural tracts during this period. Levels of PM2.5 were lower in rural tracts compared to urban and fell more rapidly in rural than urban. Rural tract annual means for 2010 and 2019 were 8.51 [2.24] μg/m3 and 6.41 [1.29] μg/m3, respectively. Urban tract annual means for 2010 and 2019 were 9.56 [2.04] μg/m3 and 7.51 [1.40] μg/m3, respectively. Rural and urban majority Black communities had significantly higher PM2.5 pollution levels (10.19 [1.64] μg/m3 and 9.79 [1.10] μg/m3 respectively), in 2010. In 2019, they were: 7.75 [1.1] μg/m3 and 7.09 [0.78] μg/m3, respectively. Majority Hispanic communities had higher PM2.5 levels and were the highest urban concentration among all races/ethnicities (8.01 [1.73] μg/m3), however they were not the highest rural concentration among all races/ethnicities (6.22 [1.60] μg/m3) in 2019. Associations with higher levels of PM2.5 were found with communities in the poorest quartile and with higher proportions of residents age<15 years old. These findings suggest greater protections for those disproportionately exposed to PM2.5 are needed, such as, increasing the availability of low‐cost air quality monitors. Plain Language Summary PM2.5 is a well‐known air pollutant that impacts human health. However, little is known about how it differs between urban and rural areas in the United States (U.S). This study investigated these differences between 2010 and 2019 at a level that had not been assessed before across the United States. Rural areas generally had lower PM2.5 levels compared to urban areas and the pollution decreased faster in rural areas during this time. Both rural and urban areas with higher proportions of residents that are Black, Hispanic, and in poverty had higher PM2.5 levels. There were no consistent patterns between the age distribution of urban or rural census tracts and PM2.5 levels. Key Points Between 2010 and 2019, PM2.5 levels were consistently lower in rural communities than in urban communities across the United States High percentage Black communities had significantly higher PM2.5 pollution levels in both rural and urban census tracts Greater protection from air pollution for socially disadvantaged communities in both rural and urban settings is warranted

• Publisher: John Wiley & Sons, Inc,John Wiley and Sons Inc,American Geophysical Union (AGU)
• Subject: Agricultural production / air monitoring / Air pollution / Air quality / Censuses / Ethnicity / Fossil fuels / General or Miscellaneous / Geohealth / Industrial plant emissions / Land use / Outdoor air quality / Particulate matter / PM2.5 / Pollution levels / Poverty / Power plants / Rural areas / Rural urban differences / socially disadvantaged communities / Trends / Urban areas / urban versus rural