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Beuck H.,Air Quality and Sustainable Nanotechnology Unit | Beuck H.,University of Munster | Quass U.,Air Quality and Sustainable Nanotechnology Unit | Klemm O.,University of Munster | Kuhlbusch T.A.J.,Air Quality and Sustainable Nanotechnology Unit
Atmospheric Environment | Year: 2011

In order to assess the contribution of natural sources (sea salt and mineral dust) to PM 10 levels in North-West Germany, a one year measurement project was conducted at two sites between April 2008 and March 2009. The sites were located in an urban and a regional background area. A Positive Matrix Factorization (PMF) based source apportionment study was carried out using chemical composition data of PM 10 and PM 1 filter samples from 79 selected days in a pooled dataset yielding eight source related factors. High to moderate urban versus regional correlations are obtained for factors denoted as aged marine aerosol, aged mineral dust, secondary sulfate and fossil fuel combustion. The factors identified as secondary nitrate, biomass combustion, re-suspended road dust and industry do not correlate significantly. Since the PMF factors do not represent the natural sources in the meaning of the EU air quality directive, tracer methods based on sodium, chloride and calcium are proposed to infer the PM 10 concentrations of natural sea salt, mineral dust background, and the impact of long-range dust intrusions on PM 10 concentrations, respectively. These tracer methods are viewed suitable for application in routine source apportionment within the air quality monitoring network. © 2011 Elsevier Ltd. Source


Molnar P.,Gothenburg University | Johannesson S.,Gothenburg University | Quass U.,Air Quality and Sustainable Nanotechnology Unit
Aerosol and Air Quality Research | Year: 2014

Personal exposure, indoor, residential outdoor and urban background particulate matter (PM2.5) samples were collected in parallel, for 30 participants and analyzed for their chemical content. Source apportionments for the separate microenvironments were performed using conventional positive matrix factorization (PMF), and for the combined dataset, applying a new PMF method with factor selection. Regional sources were the largest contributor to the sampled PM2.5 in all microenvironments and accounted for 69% in urban background; 55% and 54% in residential outdoor and indoor environment, respectively; and 40% of personal exposure. For personal exposure, personal activities accounted for 21% (2.2 μg/m3), and constituted the main difference in total mass concentration between personal exposure and the other microenvironments. The PMF method with factor selection was found to be a useful tool in the PMF analysis of multiple microenvironments, since ambient contributions to indoor and personal exposure are less likely to be distorted or misinterpreted. The possibility to more correctly estimate the source contributions will increase by combining the datasets for the different microenvironments into a larger dataset and using the PMF with factor selection method. © Taiwan Association for Aerosol Research. Source

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