Seasonal Mapping of Inhalation-Level Urban Aerosol in Washington, DC

Particulate matter is a known health hazard in urban environments - especially as the [population density increases. Many epidemiological studies have indicated a positive correlation between the level of PM in the atmosphere and mortality from lung cancer and cardiovascular diseases. However, the lack of sufficient information on the size, biological, and chemical composition of these particulate has been a major challenge in predicting and relating particle associated health risks.

We have collected observations of the seasonal characteristics of inhalation-level particulate in Washington, DC using a combination of in situ approaches and then mapped their spatial distribution using GIS. In addition to these physical measurements of size-resolved number and mass density, aerobiological characterization has been performed. We present an analysis of the results of these data and computed fluxes of the PM as a function of size to further clarify exposures and the spatial variability across two seasons in an urban setting. This methodology employed in this study may be useful in identifying danger zones and high-risk areas based on seasonal behaviors and urban development and transferable to other urban centers.