Air quality sensors and distributional environmental justice: a case study of Salt Lake County, Utah

Ambient fine particulate matter (PM2.5) causes health problems and is monitored by U.S. federal and state governments. Due to gaps in public monitoring, people rely on non-regulatory air quality monitoring networks (NAQMNs), comprised of low-cost PM2.5 sensors, to obtain air quality information. While environmental justice studies have examined social disparities in PM2.5 and sensor distribution, none have examined disparities in university-purchased vs. privately-purchased sensor distributions. This is important because who purchases sensors (and why) may impact sensor distribution equity. Using multivariable generalized estimating equations, we investigate university-purchased (n=68) and privately-purchased (n=230) sensors in the Salt Lake County, Utah NAQMN with a focus on socioeconomic status (SES), race/ethnicity/immigrant status, and PM2.5 at the census tract-level (n=208). Tracts with higher SES and PM2.5 concentrations had increased sensors per resident. Findings related to SES attenuate when predicting university-purchased vs. privately-purchased sensors. Tracts with greater Hispanic immigrant populations and higher PM2.5 concentrations had increased access to university-purchased sensors. Tracts with higher Asian concentrations were underserved regardless of sensor purchaser. This approach illuminates how university-purchased sensors may enhance distributional environmental justice. Findings have implications for enhancing equitable sensor distribution in NAQMNs.