• Title/Summary/Keyword: Fraction of pollutants

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Ultrafine Particle Events in the Ambient Atmosphere in Korea

  • Maskey, Shila;Kim, Jae-Seok;Cho, Hee-Joo;Park, Kihong
    • Asian Journal of Atmospheric Environment
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    • v.6 no.4
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    • pp.288-303
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    • 2012
  • In this study, real time measurements of particle number size distribution in urban Gwangju, coastal Taean, and industrial Yeosu in Korea were conducted in 2008 to understand the occurrence of ultrafine particle (UFP) (<100 nm) events, the variation of its concentration among different sampling sites, and UFP formation pathways. Also, to investigate seasonal and long-term variation of the UFP number concentration, data were collected for the period of 5 years (2007, 2008, 2010, 2011, and 2012) in urban Gwangju. Photochemical and combustion events were found to be responsible for the formation of UFP in the urban Gwangju site, whereas only photochemical event led to the formation of UFP in the coastal Taean site. The highest UFP concentration was found in industrial Yeosu (the average UFP number fractions were 79, 59 and 58% in Yeosu, Gwangju, and Taean, respectively), suggesting that high amount of gas pollutants (e.g., $NO_2$, $SO_2$, and volatile organic carbon (VOC)) emitted from industries and their photochemical reaction contributed for the elevated UFP concentration in the industrial Yeosu site. The UFP fraction also showed a seasonal variation with the peak value in spring (61.5, 54.5, 50.5, and 40.7% in spring, fall, summer, and winter, respectively) at urban Gwangju. Annual average UFP number concentrations in urban Gwangju were $5.53{\times}10^3\;cm^{-3}$, $4.68{\times}10^3\;cm^{-3}$, $5.32{\times}10^3\;cm^{-3}$, $3.99{\times}10^3\;cm^{-3}$, and $2.16{\times}10^3\;cm^{-3}$ in the year 2007, 2008, 2010, 2011, and 2012, respectively. Comparison of the annual average UFP number concentration with urban sites in other countries showed that the UFP concentrations of the Korean sites were lower than those in other urban cities, probably due to lower source strength in the current site. TEM/EDS analysis for the size-selected UFPs showed that the UFPs were classified into various types having different chemical species. Carbonaceous particles were observed in both combustion (soot and organics) and photochemical events (sulfate and organics). In the photochemical event, an internal mixture of organic species and ammonium sulfate/bisulfate was identified. Also, internal mixtures of aged Na-rich and organic species, aged Ca-rich particles, and doughnut shaped K-containing particles with elemental composition of a strong C with minor O, S, and K-likely to be originated from biomass burning nearby agricultural area, were observed. In addition, fly ash particles were also observed in the combustion event, not in the photochemical event.

Prevalence of Allergic Rhinitis between Urban and Rural Residents in a Local Community (일개 시 지역의 도심과 농촌 주민의 알레르기비염 유병률)

  • Choi, Byoung-Kwon;Lim, Hyun-Sul;Chung, You-Sun
    • Journal of agricultural medicine and community health
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    • v.40 no.3
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    • pp.148-157
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    • 2015
  • Objectives: The purpose of this study was to examine the prevalence of allergic rhinitis between urban areas in the adjacent areas to a steel industrial complex and rural areas and the impact of pollutants in the industrialized city on allergic rhinitis. Methods: From July 28 to August 9 of 2008, 1,043 residents of urban and rural areas in a local community had enrolled in health screening and questionnaire survey. One thousand thirty-three patients also underwent a skin prick test. Prevalence rates of allergic rhinitis were calculated according to residential areas, and the used statistical analysis were Fisher's exact test and chi-square test. Results: In a survey, the fraction of adults, who complained of sneezing, nasal obstruction and rhinorrhea, during a recent 1 year period, showed the significant difference between urban (30.5%) and rural areas (22.4%). The fractions of positive skin prick tests were not different between two areas in each age group. The prevalence of allergic rhinitis was 8.4% in urban areas and 6.9% in rural areas. Considering the age groups, the adults group only showed the significantly higher prevalence of allergic rhinitis in urban areas (8.2% vs. 3.7%). Conclusions: Unlike the children and adolescents groups, the prevalence of allergic rhinitis in adults group was higher in the industrialized urban areas.

Occupational exposure to polycyclic aromatic hydrocarbons in Korean adults: evaluation of urinary 1-hydroxypyrene, 2-naphthol, 1-hydroxyphenanthrene, and 2-hydroxyfluorene using Second Korean National Environmental Health Survey data

  • Dong Hyun Hong;Jongwon Jung;Jeong Hun Jo;Dae Hwan Kim;Ji Young Ryu
    • Annals of Occupational and Environmental Medicine
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    • v.35
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    • pp.6.1-6.15
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    • 2023
  • Background: Polycyclic aromatic hydrocarbons (PAHs) are occupational and environmental pollutants generated by the incomplete combustion of organic matter. Exposure to PAHs can occur in various occupations. In this study, we compared PAH exposure levels among occupations based on 4 urinary PAH metabolites in a Korean adult population. Methods: The evaluation of occupational exposure to PAHs was conducted using Second Korean National Environmental Health Survey data. The occupational groups were classified based on skill types. Four urinary PAH metabolites were used to evaluate PAH exposure: 1-hydroxypyrene (1-OHP), 2-naphthol (2-NAP), 1-hydroxyphenanthrene (1-OHPHE), and 2-hydroxyfluorene (2-OHFLU). The fraction exceeding the third quartile of urinary concentration for each PAH metabolite was assessed for each occupational group. Adjusted odds ratios (ORs) for exceeding the third quartile of urinary PAH metabolite concentration were calculated for each occupational group compared to the "business, administrative, clerical, financial, and insurance" group using multiple logistic regression analyses. Results: The "guard and security" (OR: 2.949; 95% confidence interval [CI]: 1.300-6.691), "driving and transportation" (OR: 2.487; 95% CI: 1.418-4.364), "construction and mining" (OR: 2.683; 95% CI: 1.547-4.655), and "agriculture, forestry, and fisheries" (OR: 1.973; 95% CI: 1.220-3.191) groups had significantly higher ORs for 1-OHP compared to the reference group. No group showed significantly higher ORs than the reference group for 2-NAP. The groups with significantly higher ORs for 1-OHPHE than the reference group were "cooking and food service" (OR: 2.073; 95% CI: 1.208-3.556), "driving and transportation" (OR: 1.724; 95% CI: 1.059-2.808), and "printing, wood, and craft manufacturing" (OR: 2.255; 95% CI: 1.022-4.974). The OR for 2-OHFLU was significantly higher in the "printing, wood, and craft manufacturing" group (OR: 3.109; 95% CI: 1.335-7.241) than in the reference group. Conclusions: The types and levels of PAH exposure differed among occupational groups in a Korean adult population.

Chemical characteristics of wet precipitation in urban and mountainous sites of Jeju Island

  • Bu, Jun-Oh;Song, Jung-Min;Park, Sook-Young;Kang, Hee-Ju;Kang, Chang-Hee
    • Analytical Science and Technology
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    • v.33 no.1
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    • pp.33-41
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    • 2020
  • Wet precipitation samples were collected in Jeju City and Mt. Halla-1100 site (a site at an altitude of 1100 m on Mt. Halla) during 2011-2013, and their major ionic species were analyzed to examine the chemical composition and characteristics. A comparison of ion balance, electric conductivity, and acid fraction of precipitation revealed correlation coefficients in the range of r = 0.950~0.991, thereby implying the high quality of analytical data. Volume-weighted mean pH and electric conductivity corresponded to 4.86 and 25.5 µS/cm for Jeju City, and 4.98 and 15.1 µS/cm for Mt. Halla-1100 site, respectively. Ionic strengths of the wet precipitation in Jeju City and Mt. Halla-1100 site corresponded 0.3 ± 0.5 and 0.2 ± 0.2 mM, respectively, thereby indicating that more than 30 % of total precipitation was within a pure precipitation criteria. The precipitation with a pH range of 4.5 - 5.0 corresponded to 40.8 % in Jeju City, while the precipitation with a pH range of 5.0 - 5.5 corresponded to 56.9 % in Mt. Halla-1100 site, thereby indicating slightly more weak acidity than that in Jeju city. The volume-weighted mean concentration (µeq/L) of ionic species was in the order of Na+ > Cl- > nss-SO42- > NO3- > Mg2+ > NH4+ > H+ > nss-Ca2+ > PO43- > K+ > CH3COO- > HCOO- > NO2- > F- > HCO3- > CH3SO3- at Jeju City area, while it corresponded to Na+ > Cl- > nss-SO42- > NO3- > NH4+ > H+ > Mg2+ > nss-Ca2+ > PO43- > CH3COO- > K+ > HCOO- > NO2- > F- > HCO3- > CH3SO3- at Mt. Halla-1100 site. The compositions of sea salts (Na+, Cl-, Mg2+) and secondary pollutants (NH4+, nss-SO42-, NO3-) corresponded to 66.1 % and 21.8 %, respectively, in Jeju City and, 49.9 % and 31.5 %, respectively, in Mt. Halla-1100 site. The acidity contributions in Jeju City and Mt. Halla-1100 site by inorganic acids, i.e., sulfuric acid and nitric acid, corresponded to 93.9 % and 91.4 %, respectively, and the acidity contributions by organic acids corresponded to 6.1 % and 8.6 %, respectively. The neutralization factors in Jeju City and Mt. Halla1100 site by ammonia corresponded to 29.8 % and 30.1 %, respectively, whereas the neutralization factors by calcium carbonate corresponded to 20.5 % and 25.2 %, respectively. From the clustered back trajectory analysis, the concentrations of most ionic components were higher when the airflow pathways were moved from the continent to Jeju area.

A Study on the Measurement of the Dimensionless Light Extinction Constant for Particulate Matter from Fuel Oil for Marine and Land Diesel Engines (선박 및 육상 디젤 엔진용 연료유에서 발생하는 입자상물질에 대한 무차원 광소멸계수 계측에 관한 연구)

  • Rho, Beom-Seok;Choi, Jae-Hyuk;Cho, Kwon-Hae;Park, Seul-Hyun;Lee, Won-Ju
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.2
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    • pp.275-281
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    • 2018
  • It is known that he pollutant emitted from the combustion process of marine fuel oil causes air pollution and harmful effects to the human body. Accordingly, IMO regulates pollutants emitted from ships. However, the regulation of Particulate Matter (PM) is still in the process of debate, so preemptive action is needed. Fundamental research on PM is essential. In this study, the Dimensionless Light Extinction Constant ($K_e$) of fuel oil used in marine diesel engines was measured and analyzed to construct the basic data of the PM generated from marine-based fuel oil. The fuel oil used in the land diesel engine was measured in the same way for character comparison. Both fuel oils differ in sulfur content and density. The $K_e$ was measured via the optical method using a 633 nm laser and was determined by using the volume fraction of PM collected by the gravimetric filter method. The $K_e$ of the PM discharged from marine fuel oil is 8.28, and the land fuel oil is 8.44. The $K_e$ of two fuel oils was similar within the measurement uncertainty range. However, it was found by comparison with the value obtained by the Rayleigh-Limit solution that the light scattering portion could be large. Also, it was found that light extinction characteristics could be different due to the relationship between light transmittance and collected mass.