A three-dimensional chemical transport model (CTM), PMCAMx-2008, was applied to Europe to study the influence of emissions changes on fine PM levels. Various emissions scenarios were studied, covering summer and winter periods to quantify also the seasonal variation. Reduction of NH3 emissions seems to be the most effective control strategy for reducing PM2.5 over Europe, in both seasons, mainly due to reduction of NH4NO3. A reduction of SO2 emissions has a significant effect on PM2.5 levels over the Balkans during summer, due to decrease of sulfate, while the reduction of anthropogenic OA emissions has a strong effect on total OA mainly in areas close to emissions sources. The NOx emissions control strategy seems to be problematic in both seasons. Our analysis in European Megacities, based on a scenario zeroing all anthropogenic emissions, showed that the contribution of local emissions on total PM2.5, depends on the chemical component, with local sources being especially important mainly for black carbon (BC).