Our paper presents the results of the integrated assessment modelling of environmental and human health impacts of emissions in Poland. The analysis was performed based on the so-called National Scenario. The estimated emission levels of SO₂, NO_x, and PMs for 2020 were used as the input data to model ambient concentrations and depositions of these pollutants. Exceedances of critical loads of acidity caused by nitrogen and sulphur depositions were calculated. External costs associated with human health impacts of air pollution were estimated. Additionally, ambient concentration of gaseous and particulate Hg were modelled based on 2005 EMEP emissions data. The main part of the analysis was carried out using the Eulerian Chemistry Transport Model POLAIR3D.