Combining Black Carbon and PM monitoring to identify local sources of pollution in Washington, DC

Low-cost air quality monitors are a crucial tool for communities to document exposure to pollutants. Their cost and ease of installation and maintenance allow residents to set up networks of monitors to identify air pollutant levels and sources within neighborhoods. We show results from a network of PurpleAir air quality monitors deployed in the Washington, DC neighborhoods of Buzzard Point, Brentwood, and Ivy City over the course of 3 years. The data collection was initiated by residents of these overburdened communities surrounded by a major thoroughfare, industrially-zoned areas, bus and heavy-duty vehicle parking, diesel truck traffic and railroad tracks.

Several PurpleAir monitors were deployed at volunteer residents across the neighborhoods to measure atmospheric concentrations of fine particulate matter (PM2.5). Additionally, we co-located two black carbon (BC) monitors with PurpleAir monitors in Brentwood and Ivy City. Using this dataset, we document the temporal and spatial variability of PM2.5 concentrations within the neighborhoods and compare local to city-wide concentrations of air pollutants from regulatory monitors and publicly available PurpleAir monitors. Through the relative variations of PM2.5 and BC and their correlation to the local meteorology, we can separate regional sources of air pollution from local ones (e.g. major roadways in Brentwood and construction sites in Buzzard Point).