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Updated: Jul 2, 2026
13:48
Design and Construction of an Urban Runoff Research Facility
Published on: August 8, 2014
[PAH sources in road runoff system in Beijing]
Wei Zhang1, Shu-cai Zhang, Chao Wan
1Ministry of Education Laboratory of Earth Surface Processes, College of Environmental Sciences, Peking University, Beijing 100871, China. wzhang@pku.edu.cn
Huan Jing Ke Xue= Huanjing Kexue
|September 4, 2008
Summary
Polycyclic aromatic hydrocarbons (PAHs) in Beijing
Area of Science:
- Environmental Chemistry
- Urban Pollution Studies
- Atmospheric Science
Background:
- Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants originating from incomplete combustion processes.
- Urban environments are significant sources and sinks for PAHs due to traffic and industrial activities.
- Understanding PAH sources is crucial for assessing environmental and health risks in populated areas.
Purpose of the Study:
- To investigate the sources and distribution of polycyclic aromatic hydrocarbons (PAHs) in various environmental media within Beijing.
- To analyze seasonal variations in PAH concentrations across different road types.
- To differentiate the contributions of vehicular emissions and other combustion sources to environmental PAH loads.
Main Methods:
- Collection of environmental samples including road runoff, rainwater, ground sediment, and roadside tree water from three distinct road types in Beijing during 2006.
- Quantitative analysis of polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry.
- Application of factor analysis and multiple regression analysis to identify PAH sources and their contributions.
Main Results:
- Average polycyclic aromatic hydrocarbon (PAH) concentrations were higher in May-June compared to July-August across all sampled media.
- Factor analysis revealed ground sediment as the primary source of PAHs in road runoff, with contributions from rainwater and roadside tree water.
- Multiple regression indicated vehicular emissions as the dominant source for PAHs in ground sediment and road runoff on vehicle and branch roads, while vehicular emissions and coal combustion contributed equally on bicycle paths.
Conclusions:
- Seasonal variations in PAH levels are evident, with higher concentrations during cooler months.
- Roadside environments act as complex systems where PAHs from sediment, traffic, and atmospheric deposition interact.
- Vehicular emissions are a major contributor to PAHs in urban road environments, with coal combustion playing a significant role in specific areas like bicycle paths.
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