Accessibility to Localized Fine Particulate Matter (PM2.5) Data from Purple Air Sensors in Major U.S. Cities

MOHAMMED AHMED, Daniel Gingerich, Andrew May, The Ohio State University

     Abstract Number: 295
     Working Group: Urban Aerosols

Abstract
PM2.5 is one of the leading causes of mortality worldwide and if people are aware of their exposure to PM2.5, they can take appropriate precautions to reduce risks. The Purple Air (PA) network is by far the most widespread low-cost PM2.5 sensor network in the U.S., and hence, has potential to provide localized exposure estimates for nearby residents. We leveraged this network to estimate the spatial accessibility to active PA sensors installed by any user (e.g., non-governmental or personal) at the census-tract level in 32 highly-populated U.S. cities (> 500,000 residents). We found that 14% of the total population of the median city lives within 1-km of a PA sensor, but there is high variability between cities (min.: 1.6%; max.: 97.5%; inter-quartile range: 5.3% – 35.8%). We extended our analysis to consider socio-demographics within 1-km of a PA sensor, including race (Whites or non-Whites), poverty level (above or below the poverty line), age (above or below eighteen), sex (male or female), and housing status (owners or renters). We used a binomial distribution test to compare the population within each buffer to the total population of the city using our defined socio-demographic variables to consider both access and equity to localized sensor data. Based on these tests, we find that across all cities analyzed, residents below the poverty line and renters are as more likely to live within 1-km of a PA sensor, while non-White residents and children tend to be less likely to have this localized access. While this is true in general, there are cities with PA sensor networks that provide more equitable access to localized PM2.5 data for non-White residents and children. Nevertheless, additional mechanisms (e.g., policies, funding) are needed to ensure equitable access to localized PM2.5 sensor data nationwide.