Due to negative effects on human health and visibility, atmospheric particulate matter (PM) is a prioritized contaminant for urban air pollution management. Over the past few decades, managing emissions have been a top priority. This paper investigated PM national inventory data and mass concentration trends for Lithuania. This analysis considers primary (sum of filterable and condensable) PM_2.5 and PM₁₀ emissions from point, mobile on-road and off-road, industry, agriculture, and waste sectors. In this study, by examining both the emissions and the mass concentrations of PM₁₀, the effects of emissions decreasing with a concentration decrease were revealed. The slower decreasing tendency of PM₁₀ and BC (0.03 Gg/year) than that of PM_2.5 (0.1 Gg/year) should be noted. Furthermore, the correlation analysis also finds that the increase in PM₁₀ from stationary and mobile combustion sources is closely related to the increase in the contribution to the pollution level.

The present study investigated the characteristics of carbonaceous species in an urban background site. Real-time measurements of inorganic (sulfate, nitrate, ammonium, chloride, and black carbon [BC]) and organic submicron aerosols (OA) were carried out at the urban background site of Vilnius, Lithuania, during January–February 2014. An aerosol chemical speciation monitor (ACSM, Aerodyne Research Inc., Billerica, MA, USA) and co-located 7-λ aethalometer (AE-31, Magee Scientific, Berkeley, CA, USA) were used to analyze the chemical compositions, sources, and extinction characteristics of the PM₁. Extremely contrasting meteorological conditions were observed during the studied period due to the transition from moderately cold (~2 °C) conditions to extremely cold conditions with a lowest temperature of −25 °C; therefore, three investigation episodes were considered. The identified periods corresponded to the transition time from the moderately cold to the extremely cold winter period, which was traced by the change in the average temperature for the study days of 1–13 January, with T = −5 °C and RH = 92%, in contrast to the period of 14–31 January, with T = −14 °C and RH = 74%, and the very short third period of 1–3 February, with T = −8 °C and RH = 35%. On average, organics accounted for the major part (53%) of the non-refractory submicron aerosols (NR-PM₁), followed by nitrate (18%) and sulfate (9%). The source apportionment results showed the five most common OA components, such as traffic and heating, to be related to hydrocarbon-like organic aerosols (HOA_traffic and HOA_heating, respectively), biomass-burning organic aerosols (BBOA), local organic aerosol (LOA), and secondary organic aerosol (SOA). Traffic emissions contributed 53% and biomass burning 47% to the BC concentration level. The highest BC and OA concentrations were, on average, associated with air masses originating from the southwest and east–southeast. Furthermore, the results of the PSCF and CWT methods indicated the main source regions that contributed the most to the BC concentration in Vilnius to be the following: central–southwestern and northeastern Poland, northwestern–southwestern and eastern Belarus, northwestern Ukraine, and western Russia. However, the potential sources of OA were widely distributed.

The effects of air pollution on the general public received much attention recently. Personal exposure and deposition fraction of aerosol particles were studied in Vilnius, Lithuania, focusing on individuals working in an office and driving to work. Aerosol monitoring in the urban background was found to give an indication of the minimum concentrations of particulate matter (PM) expected at urban roads, as these correspond to the lowest PM concentrations measured there. In March 2021, PM_2.5 concentrations at the urban background monitoring station reached values above the annual limit of 5 μg/m³ the World Health Organization in 50% of cases. Our study shows significant differences in exposure to air pollution in a car cabin and in a modern office. According to the multiple-path particle dosimetry model, the exposure of the person in the office is about 14 times lower than driving a car, where the minute deposition dose for PM₁ is 0.072 µg/min for the period when the PM_2.5 concentration in the urban background reaches 10 µg/m³. Compared to the PM_2.5 mass concentration at the urban background station, the mean PM_2.5 concentration in the vehicle reaches values that are 2–3 times higher. During the working day, when driving takes less than 10% of the time considered (commuting plus working), PM exposure during driving accounts for about 80% of the PM exposure caused by PM concentration in the office.