Particulate matter (PM) air pollution in the urban environment is mainly related to the presence of potential sources throughout the year. Road transport is one of the most important sources of PM in the urban environment, because it directly affects pedestrians. PM measurements were performed in the city of Žilina, Slovakia, at various road-traffic-related measurement stations over the course of several years. This paper evaluates changes in the concentration of the fine fraction (PM_2.5), the ultrafine fraction (PM₁), and the coarse fraction (PM_2.5–10) over time. PM concentrations were measured by reference gravimetric method. Significant changes in PM concentrations over time due to the diversification of pollution sources and other, secondary factors can be observed from the analysis of the measured data. PM samples were subjected to chemical analysis inductively coupled plasma mass spectrometry (ICP-MS) to determine the concentrations of elements (Mg, Al, Ca, Cr, Cu, Fe, Cd, Sb, Ba, Pb, Ni, and Zn). The seasonal variation of elements was evaluated, and the sources of PM_2.5, PM₁, and PM_2.5–10 were estimated using principal component analysis (PCA) and positive matrix factorization (PMF). PM_2.5 (maximum concentration of 148.95 µg/m³ over 24 h) and PM₁ (maximum concentration of 110.51 µg/m³ over 24 h) showed the highest concentrations during the heating season, together with the elements Cd, Pb, and Zn, which showed a significant presence in these fractions. On the other hand, PM_2.5–10 (maximum concentration of 38.17 µg/m³ over 24 h) was significantly related to the elements Cu, Sb, Ba, Ca, Cr, Fe, Mg, and Al. High correlation coefficients (r ≥ 0.8) were found for the elements Mg, Ca, Fe, Al, Cd, Pb, and Zn in the PM₁ fraction, Cd, Pb, and Zn in PM_2.5, and Ba, Sb, Fe, Cu, Cr, Mg, Al, and Ca in PM_2.5–10. Using PMF analysis, three major sources of PM (abrasion from tires and brakes, road dust resuspension/winter salting, and combustion processes) were identified for the PM_2.5 and PM₁ fractions, as well as for the coarse PM_2.5–10 fraction. This study reveals the importance of non-exhaust PM emissions in the urban environment.

Complying with strict PM₁₀ and PM_2.5 limit values poses challenges in many European regions, influenced by diverse factors such as natural, regional, and local anthropogenic sources. Urban air pollution, exacerbated by road transport, local industry, and dust resuspension, contrasts with rural areas affected by solid fuel-based local heating and increasing wood burning. This study focuses on village of Sučany, located in Slovakia, analysing PM concentrations during non-heating and heating seasons. The method of analysis relies on the use of the MP101M air quality analyser that utilises beta radiation absorption method. One set of measurements was conducted at five distinct locations during the heating season (18/01/2019 to 28/02/2019) and non-heating season (14/08/2018 to 1/10/2018). Significant differences emerged during the non-heating season with corresponding PM₁₀ averages of 23.0 µg/m³ and PM_2.5 at 19.3 µg/m³. In contrast, the PM₁₀ averaged 53.9 µg/m³ and 52.8 µg/m³ during the heating season. The heating season shows PM_2.5 contributing up to 98% of total PM₁₀. The distribution of PM₁₀ and PM_2.5 pollution and the location of the potential source obtained using polar plots differed during the heating and non-heating seasons. This research underscores the impact of local heating on air quality in a typical Slovak village. The key recommendation for targeted interventions is supporting up-to-date air quality data, education, and financial incentives for citizens in order to implement cleaner and modern heating solutions.

This study provides an assessment of the impact of asphalt mixture composition on the particulate matter (PM) emission from the pavement surface into the atmosphere. Pavement surface abrasion was also analyzed and potential differences among asphalt mixtures were determined by the chemical composition of captured PM. Various types of asphalt mixtures and the influence of their compositions on PM concentrations and chemical composition were studied and compared. The laboratory test setup included 12 different pavement samples. On average, the asphalt mixtures with a combination of melaphyre and dolomite as aggregates exhibited the highest values of PM. Measurements of PM_2.5 and PM₁ in the wheel tracking machine were used to study the impact of asphalt mixture properties on pavement surface abrasion. The dependence between the aggregate used in the tested mixtures and the abraded particulates has been confirmed. The Ca content in aggregates was strongly correlated with the abraded particulates, which was not observed for the Si content. The multidimensional statistical methods used showed the division of markers of the asphalt mixture materials into various factors (sources). The morphology of the solids was examined by electron microscopy with X-ray analysis, indicating the origin of the particles (aggregate, asphalt binder).

Road transport is a source of exhaust and non-exhaust emissions of particulate matter (PM). Non-exhaust PM emissions include road surface wear, tires, brakes and road dust resuspension. An important part of PM in urban air consists of particles that originate from the resuspension of road dust. This study focused on the analysis of the physicochemical properties of road dust and PM₁₀, PM_2.5 and PM₁ (PM_x) in the air (size, concentration, distribution, content of chemical elements), the properties of urban aerosol (number, mass and area distribution), and at the same time, the interconnection between the detected chemical elements in road dust and individual PM fractions in the air in order to reveal the sources of PM in the Žilina City, Slovakia. The presence of various chemical elements was found in road dust, of which the highest concentrations (more than 100 mg/g) were the elements Ca, Si and Al (specifically 373.3 mg/g, 351.4 mg/g and 113.9 mg/g on average from four sampling sites). The concentrations of PM₁₀, PM_2.5 and PM₁ were, on average, 27.2 μg/m³, 19.5 μg/m³ and 14.5 μg/m³ during the measurement period according to the reference gravimetric method. The chemical elements K, S, Cd, Sb, Pb, Ni and Zn were detected and the most represented (more than 60%) in the fine PM_2.5 fraction, and the chemical elements Mg, Al, Si, Ca, Cr, Cu, Fe and Ba were the most represented in the coarse PM_2.5–10 fraction. The analysis of the aerosol in the range of 12 nm–20 μm revealed a bimodal distribution of the collected sample of the investigated urban aerosol. This study provides a comprehensive view of the properties of road dust, airborne PM and aerosol (up to the size of nanoparticles), which can contribute to the expansion of knowledge in this field.