Source Apportionment of PM2.5 in Xinzhen,Beijing Using PIXE and XRF

Increasing attention has been paid to the influence of airborne particulate matter (APM) on human health and environment. China has set new standards for PM2.5, and adopted particular measures to control air pollution. GENT sampler was used to collect sample in Xinzhen, southwest suburb of Beijing. Proton induced X-ray emission and X-ray fluorescence were used to analyze 140 APM samples for multielements. Reliability assessment and data reconstruction were made in order to build a local air pollution elemental database, which includes elemental concentrations, sampling parameters and meteorology parameters. The source apportionment was analyzed by positive matrix factorization model. Five major sources in Xinzhen were identified and their corresponding apportionment rates were estimated. They are coal burning (29.2%), vehicle exhaust and waste incineration (26.2%), construction industry (23.3%), soil (15.4%), and industry with chlorine (5.9%). The trajectories of sources were analyzed using source contribution rates and global meteorological data. Conditional probability function and the potential source contribution function were used to determine where the sources came from, and the results correspond with surroundings.