Source Apportionment and Risk Assessment of Hazardous Air Pollutants
Date Issued
2006
Date
2006
Author(s)
Wu, Szu-Ying
DOI
en-US
Abstract
Recently, health impacts from exposures to air pollution have been widely studied. To develop effective control strategies to reduce population risks to complex air pollution, it is important to identify major sources and quantify their health risks. In this thesis, the sources of PM2.5 and VOCs were identified in the first part and the source specific health risks were calculated in the second part.
Speciated PM2.5 and VOCs collected at Beacon Hill, WA between 2000-2004 were analyzed with the multivariate receptor model, Multilinear Engine (ME). The model was performed with (1) only PM2.5 data, and (2) PM2.5 with gaseous air toxic data to compare the model’s performances. The results showed that ME model identified most sources regardless if the gaseous air toxic data were included or not. An additional source related to the background concentration of VOCs was identified when VOCs data were included. Black carbon (BC) measured from aethalometer was regressed against the apportioned diesel particle matter (DPM) and wood burning particle to evaluate if BC a good indicator of DPM. BC correlated well with both the DPM and vegetative burning particles during the heating season (Oct-Feb). Therefore, BC does not represent the actual DPM or wood burning particle mass concentrations without further detailed calibrations.
The source-specific risks were estimated by summing the products of individual air toxics concentrations in each source profile and its unit risk factor. The health risk estimates by sources showed that all sources except ‘marine’ gave a sum of cancer risks higher than 1×10-6, with the highest risk from the background VOCs sources. The improvement from having additional VOCs data in separating similar sources was not apparent. However, the combined data helped us to obtain a whole picture of the source-specific health risks.
Subjects
受體模式
來源分析
風險評估
receptor model
source apportionment
health risk assessment
Type
thesis