Abstract View
Comparing Local and Regional-Scale Particle and Gas-Phase Pollutant Exposure Disparity in a Long-Term Mobile Monitoring Campaign
SARAH CHAMBLISS, Carlos Pinon, Kyle Messier, Shahzad Gani, Brian LaFranchi, Melissa M. Lunden, Julian Marshall, Ramon Alvarez, Joshua Apte, University of Texas at Austin
Abstract Number: 595
Working Group: Environmental Justice: Technology, Frameworks, and Outcomes
Abstract
We utilize mobile monitoring of ultrafine particles (UFP), black carbon (BC), NO, and NO2 in eighteen neighborhoods within the San Francisco Bay Area to characterize both highly localized and broader urban scale variation in outdoor air pollution. Mobile laboratories were deployed on weekdays throughout a 32-month campaign, recording over 3,100 hours of data. We derive long-term spatial patterns using a temporal aggregation algorithm that calculates the median of individual drive passes within 10 m of each census block. We calculate the distribution of concentrations among the entire population of each neighborhood and among five census-based racial-ethnic groups: Hispanic/Latino, and non-Hispanic Asian, Black, White, and Other groups.
We find high within-neighborhood heterogeneity in census block-based exposure concentrations relative to between-neighborhood differences. Even with a 10-fold difference in median NO between “background” and high-emission neighborhoods, the interquartile range of NO in highly polluted neighborhoods is comparable to the absolute difference between neighborhoods. BC shows a similar trend. For UFP there are several distinctly high and distinctly low neighborhoods and a high degree of exposure overlap among intermediate-concentration areas. Concentrations of NO2 show the least overlap among neighborhoods but still exhibit substantial within-neighborhood heterogeneity.
Considering racial-ethnic exposure disparity, we find that the White non-Hispanic group experiences lower average concentrations for all pollutants, especially in comparison with Black and Hispanic/Latino populations. Population-weighted average concentrations for those groups are 10% higher for BC, over 25% higher for UFP and NO2, and over 50% higher for NO. Majority non-White neighborhoods tend to be ranked highest in median concentrations, and within some high-concentration neighborhoods the White population constitutes a disproportionate share of the lowest exposure categories. This work illustrates the complementary interaction between spatially dense measurements and coverage of a large, diverse set of neighborhoods to better understand population exposure and identify issues of environmental justice.