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Hyejung Shin
Climate and Air Quality Research Department, National Institute of Environmental Research, Incheon 404-708, Korea

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Journal article
Published: 14 July 2021 in Toxics
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Ambient particulate matter 2.5 (PM2.5) and total suspended particles (TSPs) are common airborne pollutants that cause respiratory and cardiovascular diseases. We investigated the differences of cytotoxicity and mechanism between PM2.5 and TSP activity in human alveolar epithelial A549 cells. Atmospheric samples from the central district of Seoul were collected and their chemical compositions were analyzed by inductively-coupled plasma mass spectrometry and ion chromatography. PM2.5 and TSP contained high concentrations of heavy metals (Cu, Fe, Zn, and Pb). The most abundant ions in PM2.5 were SO42−, NH4+, and NO3. A549 cells were exposed to PM2.5 and TSP (25–200 µg/mL) for 24 h. TSP was more cytotoxic than PM2.5 per unit mass. PM2.5 induced oxidative stress, as evidenced by increased levels of a glutamate-cysteine ligase modifier, whereas low-concentration TSP increased hemeoxygenase-1 levels. PM2.5 and TSP did not affect c-Jun N-terminal kinase expression. The levels of nuclear factor erythroid 2-related factor 2 (Nrf2) in PM2.5- and TSP-treated cells decreased significantly in the cytosol and increased in the nucleus. Thus, Nrf2 may be a key transcription factor for detoxifying environmental airborne particles in A549 cells. TSP and PM2.5 could activate the protective Kelch-like ECH-associated protein 1/Nrf2 pathway in A549 cells.

ACS Style

Ilseob Shim; Woong Kim; Haewon Kim; Yeon-Mi Lim; Hyejung Shin; Kwang Park; Seok Yu; Young Kim; Hwa Sung; Ig-Chun Eom; Pilje Kim; Seung-Do Yu. Comparative Cytotoxicity Study of PM2.5 and TSP Collected from Urban Areas. Toxics 2021, 9, 167 .

AMA Style

Ilseob Shim, Woong Kim, Haewon Kim, Yeon-Mi Lim, Hyejung Shin, Kwang Park, Seok Yu, Young Kim, Hwa Sung, Ig-Chun Eom, Pilje Kim, Seung-Do Yu. Comparative Cytotoxicity Study of PM2.5 and TSP Collected from Urban Areas. Toxics. 2021; 9 (7):167.

Chicago/Turabian Style

Ilseob Shim; Woong Kim; Haewon Kim; Yeon-Mi Lim; Hyejung Shin; Kwang Park; Seok Yu; Young Kim; Hwa Sung; Ig-Chun Eom; Pilje Kim; Seung-Do Yu. 2021. "Comparative Cytotoxicity Study of PM2.5 and TSP Collected from Urban Areas." Toxics 9, no. 7: 167.

Article
Published: 10 March 2021 in Air Quality, Atmosphere & Health
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Despite frequent observations of high particulate matter (PM) concentrations in Seoul, Korea, the sulfate (SO42−) concentrations in PM with an aerodynamic diameter below or equal to 2.5 μm (PM2.5) in Seoul have been reduced during the 1990s. However, there has been no decreasing trend during the 2000s. Despite the very low ambient SO2 concentrations, high SO42− concentration episodes frequently occur in Seoul; however, the reasons for this remain poorly understood. In the present study, we sought to determine the major factors that enhance sulfur oxidation in Seoul by analyzing measurement data from an intensive air quality monitoring station in the Seoul metropolitan area acquired in 2015. Additionally, we aimed to distinguish the contributions of local sources and long-range transport to the elevated SO42− concentrations in PM2.5 in Seoul. In some cases in March and October 2015, the molar ratio of SO42− to SO2, which reflects sulfur partitioning between the particle and gas phases, showed an exponential increase with an increase of relative humidity (RH). However, despite the fact that the RH was high during August 2015, no statistically significant relationship was observed between RH and the molar ratio of SO42− to SO2 during this month. In August 2015, the molar ratio of SO42− to SO2 showed an exponential increase with increasing O3 concentration. Therefore, under sufficient RH, the concentrations of radical oxidants might be the most important factor that underlies the increase in ambient SO42− concentrations. No significant relationship was observed between the molar ratio of SO42− to SO2 and O3 in October. Furthermore, using Potential Source Density Function (PSDF) and backward trajectory analysis, the high SO42− concentrations in March 2015 were found to be caused by the transportation of air pollutants from China and local sources around Seoul. The high SO42− concentrations in August 2015 are concluded to have been greatly affected by these power plant emissions in the Taean area on the west coast of Korea. The high SO42− concentrations in October 2015 appear to have been caused by the transportation of air pollutants from North Korea. In summary, the high SO42− concentration in Seoul is affected by long-range transport from China and by the emissions from around the Seoul metropolitan area, such as Taean or North Korea.

ACS Style

Na Kyung Kim; In Sun Kim; In Ho Song; Seung Myung Park; Hyung Bae Lim; Yong Pyo Kim; Hye Jung Shin; Ji Yi Lee. Temporal variation of sulfate concentration in PM2.5 and major factors enhancing sulfate concentration in the atmosphere of Seoul, Korea. Air Quality, Atmosphere & Health 2021, 14, 985 -999.

AMA Style

Na Kyung Kim, In Sun Kim, In Ho Song, Seung Myung Park, Hyung Bae Lim, Yong Pyo Kim, Hye Jung Shin, Ji Yi Lee. Temporal variation of sulfate concentration in PM2.5 and major factors enhancing sulfate concentration in the atmosphere of Seoul, Korea. Air Quality, Atmosphere & Health. 2021; 14 (7):985-999.

Chicago/Turabian Style

Na Kyung Kim; In Sun Kim; In Ho Song; Seung Myung Park; Hyung Bae Lim; Yong Pyo Kim; Hye Jung Shin; Ji Yi Lee. 2021. "Temporal variation of sulfate concentration in PM2.5 and major factors enhancing sulfate concentration in the atmosphere of Seoul, Korea." Air Quality, Atmosphere & Health 14, no. 7: 985-999.

Journal article
Published: 28 November 2019 in Atmosphere
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In this study, domestic and foreign contributions to a severe PM2.5 episode in South Korea, in which “emergency reduction measures against particulate matter” were issued, were analyzed. During the period between 27 February and 7 March in 2019 when high PM2.5 concentrations occurred, the PM2.5 concentration in the Seoul metropolitan area (SMA) in South Korea was approximately 87.3 μg/m3 on average, and a severe PM2.5 concentration level of approximately 113.4 μg/m3 was observed between 3 March and 5 March. The results of the analysis conducted using the HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model and meteorological observation data showed that northwesterly wind or westerly winds were formed during the P1 and P3 periods when the PM2.5 concentration markedly increased. When the PM2.5 concentrations in East Asia were simulated using the Community Multiscale Air Quality (CMAQ), it was found that the high PM2.5 concentrations that occurred in the SMA of South Korea were mostly affected by PM2.5 transported over long distances and following atmospheric stagnation. When the domestic and foreign contributions were evaluated using the brute-force method (BFM), the foreign and domestic contribution concentrations were found to be 62.8 and 16.8 μg/m3, respectively, during the target period of this study. It was also found that the foreign contribution was 78.8%, while the domestic contribution was 21.2%.

ACS Style

Daegyun Lee; Jin-Young Choi; Jisu Myoung; Okgil Kim; Jihoon Park; Hye-Jung Shin; Soo-Jin Ban; Hyun-Ju Park; Ki-Pyo Nam. Analysis of a Severe PM2.5 Episode in the Seoul Metropolitan Area in South Korea from 27 February to 7 March 2019: Focused on Estimation of Domestic and Foreign Contribution. Atmosphere 2019, 10, 756 .

AMA Style

Daegyun Lee, Jin-Young Choi, Jisu Myoung, Okgil Kim, Jihoon Park, Hye-Jung Shin, Soo-Jin Ban, Hyun-Ju Park, Ki-Pyo Nam. Analysis of a Severe PM2.5 Episode in the Seoul Metropolitan Area in South Korea from 27 February to 7 March 2019: Focused on Estimation of Domestic and Foreign Contribution. Atmosphere. 2019; 10 (12):756.

Chicago/Turabian Style

Daegyun Lee; Jin-Young Choi; Jisu Myoung; Okgil Kim; Jihoon Park; Hye-Jung Shin; Soo-Jin Ban; Hyun-Ju Park; Ki-Pyo Nam. 2019. "Analysis of a Severe PM2.5 Episode in the Seoul Metropolitan Area in South Korea from 27 February to 7 March 2019: Focused on Estimation of Domestic and Foreign Contribution." Atmosphere 10, no. 12: 756.

Journal article
Published: 11 May 2016 in Atmosphere
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Organic carbon (OC) accounts for a large fraction of particulate matter. Since many atmospheric organic compounds have different optical properties, it is difficult to determine the optical properties of OC accurately. In particular, hygroscopicity and light absorption of OC are important factors in understanding the aerosol optical properties. In this study, the sensitivity of organic carbon (OC) to aerosol optical properties was tested. Both the refractive index and the hygroscopicity of OC were considered. Based on the filter-based monthly averaged sampling measurement data from an intensive observation site in Seoul, Korea, the contribution of each component on the aerosol optical properties was estimated. The aerosol optical properties were simulated by combining the aerosol dynamic model for polydispersed aerosols with an optical properties model based on Mie code. The optical properties were compared with the AERONET Aerosol Optical Thickness (AOT) measurement data. In order to estimate the contribution of the light absorption and hygroscopicity of organic carbon (OC) on the optical properties of the aerosols, a sensitivity test was conducted with different imaginary refractive indices and OC hygroscopic growth factors. The results show that mass absorption efficiency can be fitted linearly as the imaginary refractive index increases. This means that one can estimate the mass absorption efficiency of OC as a function of the imaginary refractive index. The results also show that mass extinction and absorption efficiency decrease as the hygroscopic factor of OC increases because of the increase in water content. The contribution of OC to the mass extinction efficiency, however, depends on the chemical composition of other aerosol mixtures and hence, more comprehensive studies are required in this regard.

ACS Style

Chang Hoon Jung; Hye Jung Shin; Ji Yi Lee; Yong Pyo Kim. Sensitivity and Contribution of Organic Aerosols to Aerosol Optical Properties Based on Their Refractive Index and Hygroscopicity. Atmosphere 2016, 7, 65 .

AMA Style

Chang Hoon Jung, Hye Jung Shin, Ji Yi Lee, Yong Pyo Kim. Sensitivity and Contribution of Organic Aerosols to Aerosol Optical Properties Based on Their Refractive Index and Hygroscopicity. Atmosphere. 2016; 7 (5):65.

Chicago/Turabian Style

Chang Hoon Jung; Hye Jung Shin; Ji Yi Lee; Yong Pyo Kim. 2016. "Sensitivity and Contribution of Organic Aerosols to Aerosol Optical Properties Based on Their Refractive Index and Hygroscopicity." Atmosphere 7, no. 5: 65.