PM2.5 and Asthma Disparity in Relation to Social Vulnerability Index: A Case Study from Durham, North Carolina

Increased air pollution and associated disease prognosis are a serious concern in communities across the socioeconomic spectrum. Past studies have shown that a major component of air pollution, fine particulate matter (PM_2.5), is elevated in majority-Black communities in the US to greater levels than those in majority-White communities, which can potentially contribute to higher rates of respiratory health issues. In this study, we address whether PM_2.5 correlates with increased asthma rates in Durham, North Carolina. We selected monitoring sites in different census tracts within the same zip code with disparate levels of asthma to quantify and characterize PM_2.5 levels. We found that South Durham, which has higher asthma hospitalization rates, has higher average PM_2.5 levels (78.49 µg/m³) than North Durham (26.3 µg/m³). We measured the elemental composition of PM samples using transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDX) and found significant differences in the levels of Na, S, Ca, Mg, Fe, and Ti. Our data suggests that these differences in ambient PM_2.5 could contribute to differences in health outcomes in the two areas. We also discuss these differences in the context of social vulnerability within the two study sites and show that the more vulnerable site (South Durham) experiences higher pollution rates.