The health effects attributed to exposure to ambient PM2.5 concentrations above 10 ?g/m3 by using the AirQ+ modeling software were assessed. The hourly concentrations of PM2.5 were collected from 13 air pollution monitoring stations in the Belgrade district during June and July 2021., which were further used as input data for the AirQ+ software. The average concentration of PM2.5 for two-month monitoring from all sampling sites in the city was 14.8 ?g/m3, the maximum daily concentration was 55.7 ?g/m3, while the maximum concentration per hour was 365 mg/m3. The spatial distribution of concentrations was mapped using geostatistical interpolation, revealing hotspots within the city center and industrial area of the district. The burden of disease, such as stroke, ischemic heart disease (IHD), chronic obstructive pulmonary disease (COPD), and lung cancer, due to the ambient PM2.5 pollution was evaluated according to the WHO method-ology for health risk assessment of air pollution. The model used for this assessment is based on the attributable proportion defined as the section of the health effect related to exposure to air pollution in an at-risk population. The estimated attributable proportion was 19.4% for stroke, 27.2% for IHD, 15.3% for COPD and 9.0% for lung cancer. The estimated number of attributable cases per 100000 population at risk, due to PM2.5 air pollution, for stroke, IHD, COPD, and lung cancer, was 28, 34, 15, and 8, respectively.

A significant part of the population in Serbia relies on central heating systems during the winter months, with around fifty heating plants in operation across the country. Common fuels used in these plants primarily include fossil fuels such as fuel oil and natural gas. Combustion of some of these fuels leads to significant emissions of air pollutants. This study evaluates the impact on the air quality of the two heating boilers at the Valjevo city, Serbia, heating plant. Air emissions were measured separately for two heating boilers in the facility using standard reference methodology. The AERMOD air dispersion model was used to estimate the dispersion of various pollutants. A combination of topographical and meteorological data was used to set up a receptor grid exposed to air pollution within a 10 km radius around the heating plant. It was found that the resulting distribution and concentration gradient of pollutant gases and particles were less inclined towards the city center and instead spread eastwards into the surrounding villages. The health risk from the fuel oil boiler was shown to be significantly higher than that caused by the natural gas-fuelled boiler. Nevertheless, the calculated carcinogenic and non-carcinogenic health risks were within acceptable limits. However, further research is required to adequately assess the cumulative health risk generated by other surrounding emitters.

Particulate matter is widely known as a significant air pollutant due to its proven detrimental impact on human health. Furthermore, ultrafine particles (UFPs) are those with diameters smaller than 100 nm, which can cause numerous serious health effects. Thus, identifying the sources of UFPs is essential for formulating effective mitigation strategies. Quantifying the contributions of particle sources can be performed by measuring particle number size distributions (PNSDs) for specific size ranges. This study was conducted in the city of Belgrade, the capital of Serbia, and one of the largest cities in the Balkans peninsula, which, within the European framework, belongs to a region and urban area characterized by high levels of atmospheric particulate matter pollution. In addition, there is a lack of studies addressing UFP levels and their sources in Serbia, including Belgrade. Several criteria pollutants were measured, together with the UFPs and equivalent black carbon (BC) at the urban background site in the city of Belgrade, Serbia, for the period from February to August 2024. The particle sources were analyzed using Positive Matrix Factorization (PMF) of PNSDs along with equivalent BC, PM₁₀, PM_2.5, O₃, SO₂, NO, NO₂ and NO_x. Seven source types were identified, characterized, and quantified, including two traffic sources (separated into traffic 1 and traffic 2), mixed traffic, an urban diffuse source, nucleation and nucleation growth sources, and a biomass burning source. Traffic-related sources were found to have the most significant contribution at around 40% of total particles emitted, followed by nucleation-related sources (24%) and biomass burning (20%). This is the first study performed in Serbia and Belgrade that addresses source apportionment of PNSD, for particles in the range 10–400 nm.

In this study, we describe the development of seasonal winter and summer (heating and non-heating season) land use regression (LUR) models for PM_2.5 mass concentration for the city of Novi Sad, Serbia. The PM_2.5 data were obtained through an extensive seasonal measurement campaign conducted at 21 locations in urban, urban/industrial, industrial and background areas in the period from February 2020–July 2021. At each location, PM_2.5 samples were collected on quartz fibre filters for 10 days per season using a reference gravimetric pump. The developed heating season model had two predictors, the first can be associated with domestic heating over a larger area and the second with local traffic. These predictors contributed to the adjusted R² of 0.33 and 0.55, respectively. The developed non-heating season model had one predictor which can be associated with local traffic, which contributed to the adjusted R² of 0.40. Leave-one-out cross-validation determined RMSE/mean absolute error for the heating and non-heating season model were 4.04/4.80 μg/m³ and 2.80/3.17 μg/m³, respectively. For purposes of completeness, developed LUR models were also compared to a simple linear model which utilizes satellite aerosol optical depth data for PM_2.5 estimation, and showed superior performance. The developed LUR models can help with quantification of differences between seasonal levels of air pollution, and, consequently, air pollution exposure and association between seasonal long-term exposure and possible health risk implications.

Carbonaceous aerosol measurements are scarce in the Western Balkans. We present year-round observations (2023 to 2025) from the urban-background site Ada Marina, Belgrade (44.790166° N, 20.4169° E; 71 m a.s.l.), combining three source apportionment (SA) approaches (organic tracers, the aethalometer model, and a novel application of non-negative matrix factorization, NNMF, to aethalometer data) with FLEXPART modelling and gridded emissions to identify source regions and transport pathways. The annual mean equivalent black carbon (eBC) concentration was 1.42 ± 1.40 µg m⁻³, indicating a moderate eBC burden, while PM₁₀ (27.7 µg m⁻³) remained below current EU and Serbian limits but above WHO guidelines and upcoming EU limits. All SA methods consistently show strong winter to summer seasonality driven by residential wood combustion (RWC). The aethalometer model attributes 64 % of eBC to solid fuel (eBCSF) in winter versus 18 % in summer, NNMF yields 51 % versus 6 %, and offline analysis of tracers show elemental carbon from biomass burning (ECBB) contributions of 48 % versus 3 %. Organic carbon (OC) shows similar seasonality, with biomass burning contributing 59 % in winter and 4 % in summer. A substantial wintertime secondary OC component linked to RWC is evident, with secondary OC (SOC) strongly correlated with ECBB and eBCSF (R² = 0.78 to 0.86), alongside enhanced brown carbon absorption (29 % annually; 44 % in winter). FLEXPART indicates pollution episodes are dominated by regional transport within Serbia and the Pannonian Basin, while correlations between modelled residential emissions and observations demonstrate strong model skill.

Ultrafine particles (UFPs) are particles which can penetrate deeply into the respiratory system due to their small size and can translocate into the bloodstream, where they are linked to oxidative stress, inflammation, and adverse cardiovascular outcomes. Ultrafine particles can originate from direct emissions or processes of new particle formation (NPF) which we investigated in this study. New particle formation is the process by which molecular clusters form and then grow to larger particles and develop to nucleation and Aitken mode particles. This study presents a detailed analysis of ultrafine particle dynamics in the city of Belgrade, Serbia, based on high-resolution particle number size distribution (PNSD) measurements performed at an urban background site in the period from January to March 2020. A total of seven factors were identified using Positive Matrix Factorization (with contributions in brackets): three attributed to traffic, including mixed source (55%), biomass burning (26%), nucleation (11%), and urban diffuse (8%) sources. The results were obtained by measuring size-resolved number concentrations (10–400 nm) and other pollutants (NO, NO₂, NO_x, CO, O₃, PM₁, PM_2.5, PM₁₀, equivalent black carbon, organic carbon). Wind directional analysis revealed clear spatial signatures, with nucleation linked to south-western winds and primary factors associated with major local emission influences. The results provide the first combined characterization of new particle formation processes and source-resolved ultrafine particle contributions in Belgrade, offering new insights into wintertime urban exposure in Southeastern Europe.