[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.14191/Atmos.2018.28.3.337

Characteristics of Ultrafine Particles in Urban Areas Observed Worldwide and in Korea: Sources and Emissions, Spatial and Temporal Distributions, and Health Effects

Choi, Wonsik (Department of Environmental Atmospheric Sciences, Pukyong National University)
Kim, Jae-Jin (Department of Environmental Atmospheric Sciences, Pukyong National University)

Publication Information

Atmosphere / v.28, no.3, 2018 , pp. 337-355 More about this Journal

Abstract

Ultrafine particles (< 100 nm in diameter, UFP) are known to be more toxic per unit mass than larger particles and contribute to more than 90% in particle number concentrations in urbanized cities but much less in mass. The major sources of UFP are vehicle emissions in urban areas. Due to their tiny size (the sizes of UFP from vehicle emissions range from 10 to 60 nm depending on engine and fuel types), inhaled UFP can reach the deepest area of respiratory track (e.g., pulmonary alveoli) as well as all of the body via lymph and blood circulation causing various adverse health effects. This article reviews the sources and emission factors of UFP, temporal and spatial distributions in urban areas and their health effects reported by toxicological and epidemiological studies. We also compared the levels of UFP concentrations measured in other countries with those in Korean cities to evaluate the public exposure to UFP in Korea. Ultimately, we expect this study can contribute to developing the risk assessment techniques for public exposure to UFP in the urbanized cities in Korea.

Keywords

Ultrafine particles in Korea; particle number emission factors; vehicle emissions; microenvironments; pedestrian exposure;

Citations & Related Records

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