Concentrations and source contributions of particulate organic matter before and after implementation of a low emission zone in Munich, Germany

Within the Munich low emission zone (LEZ), samples of PM2.5 were collected before (2006/2007) and after (2009/2010) the implementation of the LEZ. The samples were analyzed for carbon fraction (EC/OC) and particulate organic compounds (POC). Significant lower concentrations were noticed for elemental carbon (EC) and some of the POC like vanillic acid, acetosyringone, syringylacetone and syringic acid after the implementation of the LEZ. Higher concentrations of levoglucosan, retene and O-PAH were detected in the second sampling period. Positive matrix factorization (PMF) was used to identify the main sources of POC. Emissions from traffic, solid fuels combustion, cooking and mixed source were separated. The contribution of traffic source factor was decreased about 60% after the implementation of the LEZ. Thus the average concentration of EC from traffic factor decreased from 1.1 to 0.5 μg/m3 after the implementation of the LEZ.

► Samples of PM2.5 were analyzed before and after implementation of the low emission zone (LEZ).
► Significant effect of implementation of LEZ was detected on the concentrations of EC and some of the POC.
► Source apportionment of PM2.5 was obtained using positive matrix factorization (PMF).
► Data included particulate organic compounds (POC) and EC/OC.
► The contribution of traffic factor decreased about 60% after implementation of the LEZ.