Kim, Nam Geon Jeong, Sang Bin JIN, HYOUN CHER Lee, Jiwon Kim, Kyung Hwan Kim, San Park, Yongmi Choi, Wonsik Kwak, Kyung-Hwan Lee, Hyunho Kang, Giwon Kim, Changhyuk Woo, Sang-Hee Lee, Seokhwan Kim, Woo Young Ahn, Kangho Lee, Kwan-Young Lee, Seung-Bok 2024-01-19T08:32:39Z 2024-01-19T08:32:39Z 2023-08-17 2023-10 0048-9697 https://pubs.kist.re.kr/handle/201004/113237 In urban areas, particulate matter emitted from vehicles directly affects the health of citizens near roads. Thus, in this study, particle size distribution was measured by the horizontal and vertical distances along a highway road with heavy traffic to characterize the dispersion phenomena of particulate matter emitted from vehicles. In addition, the contribution of pollution sources was analyzed using a source-receptor model. A concentration gradient was observed in which the concentration decreased with the increase in the distance from the road when the wind blew from the road to the monitoring locations. The concentration was slightly higher within 50 m of the road when the wind blows parallel to the road, and similar concentrations were found at the other monitoring locations further away from the roads. In particular, the higher the turbulence intensity of the wind, the lower is the concentration gradient coefficient because of the more enhanced mixing and dispersion. A positive matrix factorization (PMF) model with the measured particle size distribution data in the range of 9-300 nm resulted in a contribution of about 70 % (number) and 20 % (mass) to particle concentrations because of six types of vehicles including LPG, two gasoline vehicles (GDI, MPI), and three diesel vehicles with 3rd, 4th, and 5th emission classes. It showed a decrease in the vehicular contribution as the distance from the road increased. Particle number concentrations decreased with increasing altitude up to 30 m above the ground. The results of this study can be useful in deriving generalized gradient equations of particle concentrations exposed by distance and wind direction at the roadside using traffic and meteorological conditions and for establishing environmental policies, such as roadside exposure assessment, in the future. A capsule abstract: Dispersion of particles emitted from vehicles on a busy highway was characterized by roadside measurements of horizontal and vertical profiles of particle size distributions measured at four locations. The source profiles and contributions were estimated by major sources using a source-receptor model such as PMF. English Elsevier BV Spatial and PMF analysis of particle size distributions simultaneously measured at four locations at the roadside of highways Article 10.1016/j.scitotenv.2023.164892 1 Science of the Total Environment, v.893 Science of the Total Environment 893 Y scie scopus 001031401700001 2-s2.0-85163202106 Environmental Sciences Environmental Sciences & Ecology Article POSITIVE MATRIX FACTORIZATION ULTRAFINE PARTICLES AIR-POLLUTION SOURCE APPORTIONMENT BLACK CARBON WIDE AREA AEROSOL DOWNWIND IMPACTS ROADWAY Particle size distribution Roadside measurement Vehicle emission On -road air pollution Mobile laboratory Drone Source -receptor model