Atmospheric Oxidants Measurement Study

Title: Development and Deployment of an Instrumentation Suite for Comprehensive Air Quality Characterization Including Aerosol ROS

Investigators: Rodney Weber, Ph.D. (PI, Georgia Tech), Michael Bergin, Ph.D. (Georgia Tech), James Mulholland, Ph.D. (Georgia Tech), Athanasios Nenes, Ph.D. (Georgia Tech), Jeremy Sarnat, Sc.D.(Emory), Stefanie Sarnat, Sc.D. (Emory), and Matthew Strickland, Ph.D. (Emory)

Objectives. Through new instrument development and extensive field studies Project 1 will comprehensively measure and characterize gas/particle mixtures of air pollutants for this Center’s multiscale air quality model validation, health impact assessments and source/process studies.  The data will complement and extend current pollutant observations across multiple scales greatly enhancing existing air quality data sets to include more exotic species for retrospective and prospective health studies in other urban settings. A focus of these new measurements will be on identifying and quantifying agents that have been implicated in causing oxidative stress.

Approach. An online instrument to measure and broadly speciate aerosol Reactive Oxygen Species (ROS) will be developed for stationary and in-vehicle measurements and included in an instrumentation package focused on semi-continuous measurements of trace gas and aerosol species. Measurements will be taken across a variety of locations in different seasons to characterize spatial, temporal and chemical distributions, sources, and physicochemical processes or linkages between components of gas/particle pollutant mixtures implicated in adverse health outcomes. Species to be measured include fine particle ROS, redox-active metals, quinones, PAHs, speciated carbonaceous compounds, and ultrafine, fine and coarse particles, along with gas-phase oxidants, VOCs, NOx, and CO.

Expected Results. For different locations and seasons, this project will generate a unique high quality data set with new components that will extensively characterize the ambient air pollutant mix in different urban environments.  The data will inform air quality modeling and health studies by specifically addressing questions on the origins, transport and transformation of constituents of multipollutant atmospheres that are relevant to human health effects.  Predictive parameterizations of the more exotic components of the air pollutant mixture measured in this project by air quality parameters routinely recorded by monitoring agencies will be used to extend the project’s unique data set to retrospective health studies and to studies in other urban settings.  Identification of chemical linkages and physicochemical mechanisms relating to PM2.5 ROS concentrations will provide a better understanding of sources, processing and health impacts. Therefore, results from Project 1 will contribute to the ability of Center Projects 2 through 4 to address regional and temporal differences in air pollution risk and health impacts of single pollutants in a multi-pollutant context.