AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Impact of Land Use on Atmospheric Quasi-Ultrafine Particles in Houston TX
INKYU HAN, Yuncan Guo, Masoud Afshar, University of Texas School of Public Health
Abstract Number: 238 Working Group: Urban Aerosols
Abstract A large number of urban populations in the world are exposed to ambient particulate matter (PM), a mixture of natural and anthropogenic pollutants. The association between the adverse health outcomes and exposure to atmospheric fine and coarse PM are well known whereas the health effects of exposure to airborne ultrafine particles (UFPs) are much less understood. Yet due to its small size and large number of particles, UFPs can be deposited at a much higher efficiency in the alveolar region than fine and coarse PM and this enhances potential risks associated with exposures to particles in this size range. An important reason for this gap in knowledge regarding increased health risks associated with exposure to UFPs is the lack of exposure assessment in urban areas. Unlike fine and coarse PM available from the national air monitoring stations across the United States, measurement of ambient UFP can be only evaluated by investigators directly conducting air sampling in the field. The main objective of the study was to examine the impact of land use on ambient quasi-UFP mass (particle size less than 0.25 micro-meter) and polycyclic aromatic hydrocarbons (PAHs) in quasi-UFP in Houston, TX. Quasi-UFP was concurrently collected at two different monitoring sites between January 2013 and December 2013. The measurements included 40 weekly integrated particle mass and PAHs. Preliminary results showed that weekly average concentrations of quasi-UFP were 5.8 ug/m3 (Industrial site) and 4.7 ug/m3 (Background). The weekly average concentrations of sum of particle bound PAHs in quasi-UFP were 2.86 ng/m3 (Industrial site) and 1.63 ng/m3 (Background). There were significant differences of weekly average of quasi-UFP mass and PAHs in quasi-UFP between the two sites. The large spatial variability in the mass and PAHs in quasi-UFP suggested the effect of local emission sources by different land use types.