AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Population Exposure to Ultrafine Airborne Particle Number and Mass Concentrations in California
XIN YU, Melissa Venecek, Anikender Kumar, Abhishek Dhiman, Michael Kleeman, University of California, Davis
Abstract Number: 612 Working Group: Aerosol Exposure
Abstract Numerous epidemiological studies have identified positive correlations between exposure to ambient particulate matter (PM) and increased risk of respiratory and cardiovascular diseases, premature mortality and hospitalization. Some toxicity studies have suggested that ultrafine particles (UFPs; Dp<0.1µm) may be especially dangerous to human health since they have higher toxicity per unit mass and can penetrate the lungs and enter the bloodstream and secondary organs. These preliminary toxicology results are suggestive but more epidemiological evidence is required before the need for new regulations on UFPs can be fully assessed.
In this work, exposure fields are calculated for ultrafine particle mass concentration (PM0.1) and ultrafine particle number concentration (PNC0.1) in California with 4km spatial resolution and hourly time resolution for the year 2010-2016. Concentrations are predicted with a regional chemical transport model that includes explicit size-resolved emissions information for all major sources of ultrafine particles and all major atmospheric transformation processes. Predictions for PNC0.1 and PM0.1 concentrations are compared to available measurements to evaluate the accuracy of simulations. Predicted source contributions to primary PM0.1 and PNC0.1 are compared to the analysis results from receptor-based Chemical Mass Balance (CMB) model and Positive Matrix Factorization (PMF) model. The contributions from most significant sources of PM0.1 and PNC0.1 are assessed over the entire state. The results provide detailed spatial and temporal variations and enhanced source apportionment information for epidemiological studies to examine the relationship between health effects and concentrations of PM0.1 and PNC0.1 in California.