Atmospheric Nitro-PAH and Oxy-PAH concentrations during the 2008 Beijing Olympics

NARUMOL JARIYASOPIT (1), WENTAO WANG (2), STACI SIMONICH (1)

(1) Department of Environmental Molecular and Toxicology, Oregon State University, Corvallis (2) College of Urban and Environmental Science, Peking University, Beijing, China

     Abstract Number: 356
     Last modified: May 10, 2010

Abstract
Atmospheric Nitro-PAH and Oxy-PAH concentrations during the 2008 Beijing Olympics
NARUMOL JARIYASOPIT$^1, WENTAO WANG$^2, STACI SIMONICH$^1
$^1 Department of Environmental Molecular and Toxicology, Oregon State University
$^2 College of Urban and Environmental Science, Peking University

Nitro-polycyclic aromatic hydrocarbon (NPAHs) and oxy-polycyclic aromatic hydrocarbons (OPAHs) are derivatives of polycyclic aromatic hydrocarbons (PAHs), originated from direct emissions from incomplete combustion process and atmospheric photochemical reactions. The concentrations of NPAHs and OPAHs have been measured worldwide. Historically, the measured NPAH concentrations were found to be approximately one or two orders of magnitude lower than PAH concentrations whereas OPAH concentrations were comparable to PAH concentrations. In the atmosphere, they are associated mostly with fine particles which can travel deeply into the lungs. Furthermore, they have been reported as direct-acting mutagens and carcinogens, making them more toxic than their parent PAHs.

During the 2008 Beijing Olympics, the Chinese government implemented intensive regional source reduction measures to improve air quality in Beijing. In general, the source control measures were aimed at reducing air pollution emissions such as, SO2, NOx and atmospheric particulate matter (PM). PM samples (aerodynamic diameter < 2.5 micro-meter) were collected in Beijing for a 2 week period prior to the Olympics, during the Olympics and a 4 week period following the Olympics (5). The particulate phase concentrations of NPAHs and OPAHs were quantified. Subsequently the comparisons between the Olympic and non-Olympic periods and between source control and non source control periods are presented. The source regions are analyzed using four-day air mass back trajectories. Meteorological data, including wind speed, wind direction, precipitation, atmospheric pressure, temperature and humidity, are included in analyzing the influence on the NPAH and OPAH concentrations. In addition, the correlation between NPAH, OPAH concentrations and the toxicity of particulate air samples which was measured using the bacterial mutation assay, are assessed. Finally, the effectiveness of source control measures in reducing NPAH and OPAH concentrations are evaluated.