• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.609-622
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• 1997

Nitrogen dioxide $(NO_2)$ has been regarded as one of the main elements among air pollutants, and we measured $NO_2$ levels of near gas range, kitchen, living room and outdoor on 489 apartments in Pusan area. $NO_2$ were sampled by using Palmes tubes (diffusion tube sampler) during August 16-25, 1995 (summer) and January 15-29, 1996 (winter), respectively. Authors wanted to know comparison of $NO_2$ levels in summer and winter, $NO_2$ levels categorized by variables, and variables affected to $NO_2$ levels. According to this study, we conducted to establish the degree of indoor-outdoor air pollution of urban apartments in Korea and methods to reduce indoor air pollution. The results of this study were summarized as follows: 1) Mean $NO_2$ levels of near gas range, kitchen, living room, and outdoor were $25.9{\pm}10.0ppb,\;23.3{\pm}8.0ppb,\;19.9{\pm}6.1ppb,\;and\;19.0{\pm}6.0ppb$ in summer, and $34.5{\pm}16.8ppb,\;28.2{\pm}13.4ppb,\;25.3{\pm}12.5ppb,\;21.8{\pm}9.8ppb$ in winter, respectively. 2) Mean $NO_2$ levels according to the floor levels were not significantly different in summer, and in winter, $NO_2$ levels were decreased as the floor levels were increasing, but those were increased above 16th floor. 3) Variables showing significant correlation(p<0.05) with $NO_2$ levels were as follows; Summer: floor level, family size, number of family during a meal, number using gas range during rice cooking per day, and natural ventilation. Winter: floor level, family size, number of person who have been respiratory disease in a house, number of family during a meal, total number of meals, and number using gas range during rice or side-dish cooking per day. 4) We suggest that the methods of reducing indoor $NO_2$ levels are ventilation during cooking, complete combustion, decreasing number and time of cooking, and substitution of fuels.

• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.53-61
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• 1994

Sungnam city, as a major satellite town, is located in the southeast of Seoul. Atmospheric conditions are so stable that air pollutants from various emissions are tend to resist change because Sungnam city is located in the Namhansansung valley. The industrial distribution of Sungnam city are composed of various manufactories such as foods, fibers, chemicals, machinery and electronics etc. The heavy metal concentrations and size distribution are the most important parameters influencing among the way in which respirable suspended particulate matter interact with the human respiratory system. Respirable suspended particulate matter was collected on glass fiber filters from April 1993 to February 1994 according to particle size using Anderson sampler during 10 days per month at Sungnam city. 6 heavy metals, Fe, Zn, Pb Mn, Cu and Cd, were analyzed by particle size with atomic absorption spectrophotometry . The results could be summarized as follows: 1. The annual arithmetic mean concentration of total suspended particulate was 116.3$\mu $g/m$^{3}$ m', seasonal variation was the highest in spring season(196.5$\mu $g/m$^{3}$) and the lowest in Summer Season(72.9$\mu $g/m$^{3}$). 2. The ratio of airborne particulate concentrations respirable to nonrepairable( Res/Non- Res) of annual arithmetic mean value was 5.8'1, seasonal variation was highest in the spring season(6.3 : 1) and lowest in the summer season(4.6 : 1). 3. During the spring season the shape of the size distribution was trimodal which showed peaks at 3 size groups, which were below of 0.43$\mu $m, 3.3∼4.7$\mu $m and above of 11.0$\mu $g/m$^{3}$ respectively. 4. Respirable suspended particulate matter concentrations of Zn, Pb Cu and Cd were the highest in below of 0.43$\mu $m as follows; 0.517$\mu $g/m$^{3}$, 0.411 $\mu $g/m$^{3}$, 0.062$\mu $g/m$^{3}$ and 0.0310$\mu $g/m$^{3}$ , respectively, Fe and Mn were the highest in the particle size range of 4.7 ∼ 7.0$\mu $m as follows; 2.504$\mu $g/m$^{3}$ and 0.095$\mu $g/m$^{3}$, respectively. 5. The Pt Cd, Zn, Cu, Fe and Mn concentrations of annual arithmetic mean value respirable to non- respirable( Res/Non- Res ) were 33.65, 19.27, 17.74, 10.54, 3.20 and 5.20, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1270-1276
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• 2005

When gas/particle partitioning of PAHs in the atmosphere approached an equilibrium state, the slope of linear regression between gas/particle partitioning coefficient($logK_p$) and subcooled liquid vapour pressure($logP_L^O$) was -1. But it was alleged that the slope of equilibrium state might not be -1 in real atmospheric environment due to heterogeneous characteristics of particulate matter. In This study, it would be found if gas/particle partitioning of PAHs segregated with particle size in equilibrium state was based on the hypothesis mentioned above. We have calculated the slopes of $logK_p$ v.s. $logP_L^O$ after collecting 10 set samples which consisted of particulate and vaporous phases. The slope was close to -1 in equilibrium states. But despite of equilibrium state, all slopes segregated with particle size were not close to -1 and those were gentler with larger particle size. The difference of slopes in equilibrium states was almost against the assumption of gas/particle partitioning theory. When the gas/particle partitioning was due to adsorption, the desorption enthalpy was different in each particle size. When it was absorption, the activity coefficient was different. The difference of desorption enthalpy and activity coefficient in each particle size indicate the heterogeneous characteristics of the bulk particle. This may be the reason for slope variation with particle size even though in an equilibrium state.

• Journal of Conservation Science
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• v.35 no.6
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• pp.652-663
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• 2019

To identify daily and annual changes in outdoor airborne fungi, it is necessary to shorten the collection cycle and increase the number of measurements. In this study, measurements were performed by employing an air sampler and potato dextrose agar media on the rooftop of National Research Institute of Cultural Heritage during a period of one year (August 2018 to July 2019). The collection cycle spanned the twenty-four seasonal divisions and the collection time was 2 p.m. and 11 p.m.. Meteorological elements were collected at intervals of one hour. Furthermore, the concentration of airborne fungi was monitored and correlation analysis with meteorological elements was subsequently conducted. Obtained results indicate that the concentration of airborne fungi is found to be highest in November, autumn, night, followed by autumn, summer, winter, and spring. The concentration, type, and dominant species of airborne fungi can vary depending on factors such as rainfall, typhoons, and yellow dust (fine dust). The concentration of airborne fungi indicates a strong positive linear relationship between precipitation, number of precipitation days, and relative humidity. The concentration of airborne fungi was related to the period of increase of dead plants in terms of nutrition source, and to the high relative humidity conditions including rainfall in terms of meteorological elements.

• Journal of the Korea Convergence Society
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• v.2 no.1
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• pp.31-36
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• 2011

This study was performed to investigate the problems of using asbestos for dental technicians. Samples for analysing were sampled by personal sampler in 40 sampling points of 10 dental laboratories in Daegu city from December 2010 to January 2011 and counted with phase contrast microscopy. The results were as follows: 1. Asbestos concentration(geometric mean) of 40 sampling points in 10 dental laboratories was 0.0061 f/cc and it was under recommended industrial and indoor air standard, but the concentration of asbestos in only two dental laboratories was over indoor recommended standard. 2. The concentration of asbestos in processing room and burnout room was 0.0099 f/cc and 0.0037 f/cc, respectively. 3. The mean concentration(GM) of asbestos by kinds of casting ring liners was 0.0159 f/cc in dental laboratories using industrial asbestos, 0.0104 f/cc in them using asbestos containing ring liners, and 0.0026 f/cc in them using non-asbestos ring liners. Casting ring liners using in dental laboratories should be substituted with non-asbestos liners, because most of dental laboratories were using asbestos containing ring liners and a few of them showed higher concentration than recommended standard.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.336-341
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• 2011

This study was carried out to investigate efficacy of aerosol sanitizer with natural antimicrobial and organic acids against Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes. The artificially inoculated pathogens on stainless steel coupon were treated with grapefruit seed extract (GFE), acetic acid, citric acid and lactic acid in model cabinet for 5 min. The number of three foodborne pathogens with individual treatment was reduced by 0.34-3.77 log units, treatment with GEF + organic acid was reduced by 1.72-3.89 log units and treatment with GEF + organic acid + alcohol was reduced by 1.46-5.05 log units. By treatment with GEF + lactic acid + alcohol in scale-up model system for 10 min. Populations of E. coli O157:H7, S. Typhimurium and L. monocytogenes were reduced by 3.42, 2.72 and 2.30 log units from the untreated control respectively. From the above result, aerosol sanitizer with natural antimicrobial agents and organic acid can be used as an environmental sanitation method with satisfying the consumer demand on safe food.

• Environmental Analysis Health and Toxicology
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• v.5 no.3_4
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• pp.19-28
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• 1990

Nitroarenes are ubiquitous environmental pollutants displaying potent mutagenicity in bacteria and carcinogenicity in mammal. In this study, the concentration of nitroarenes in coarse and fine particles and mutagenicity of POC$\_$N/ fraction was investigated in suspended particulates at the Shinchon and Bulkwang area of Seoul. The suspended particulates were collected bimonthly by a high volume cascade impactor air sampler from July 1987 to May 1988. Extractable organic matter was obtained by ultrasonic extraction on diethly ether/cyclohexane (8/2, v/v). Neutral fraction was obtained by liquid-liquid extraction. Polar neutral organic compounds (POC$\_$N/) was fractionated by thin-layer chromatography. Finally, the concentrations of nitroarenes in POC$\_$N/ fraction were measured and determined by capillary gas chromatography. Direct and indirect mutagenicity of POC$\_$N/ fraction were measured using Salmonella typhimurium TA 98. The result were as follows: 1) Major nitroarenes at the Shinchon area was 1-nitropyrene and at the Bulkwang area it was 2,7-dinitro-9-fluorenone during the year. 2) Average concentration of total nitroarenes measured was 67.26 ng/m$^3$in fine particles which was 1,3 folds higher that in coarse particle (52.30 ng/m$^3$). 3) Annual pattern of nitroarenes concentrations revealed that concentration during heating season (Feb., Jan., Mar.) was 2.2 folds higher than that in non heating season (May, Jul., Sep.). Concentration of each season has 157.68 ng/m$^3$and 80.39 ng/m$^3$. 4) The mutagenic activity of POC$\_$N/ fraction from fine particles was higher compared to that of coarse particles and was increased when metabolically activated, with 59 mixture. Mutagenicities, Metabolically activated, were significantly different between Shinchon and Bulkwang area, 322.8 rev/250 $\mu\textrm{g}$/plate and 286.8 rev/250 $\mu\textrm{g}$/plate, respectively. 5) Annual pattern of mutagenicity of POC$\_$N/ fraction revealed that mutagenicity during the heating season was 1.7 folds higher at Shinchon area and 1.2 folds higher at Bulkwang than during the non heating season. The variable contents and levels of nitroarenes in suspended particulates may affect human health significantly. Further studies such as risk assessment should be conducted on the basis of these kind of studies.

• Analytical Science and Technology
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• v.23 no.5
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• pp.465-476
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• 2010

In this study, a number of volatile organic compounds (VOCs) including benzene, toluene, p-xylene, styrene, and methyl ethyl ketone were analyzed from samples collected in ambient air and under the field conditions. These samples were analyzed independently by two different set-ups for VOC analyses, i.e., between [1] gas chromatography/flame ionization detector with tube sampling - (F-T system) and [2] gas chromatography/mass spectrometer with bag sampling (M-B system). The analytical results derived by both systems showed fairly similar patterns in relative sense but with moderately large differences in absolute sense. The results of M-B system were high relative to F-T system with the F-T/M-B ratio below 1. If the relative biases of the two measurement techniques are derived in terms of percent difference (PD) in concentration values, the results were generally above 35% on average. A student t-test was applied to investigate the statistical significance of those differences between the systems. The results of both analytical systems were different at 95% confidence level for toluene, p-xylene, styrene, and methyl ethyl ketone (P < 0.043). However, F-T and M-B systems showed strong correlations for toluene and p-xylene. The observed bias is explained in large part by such factors as the differences in standard phases used for each system and the chemical loss inside the bag sampler.

• YAKHAK HOEJI
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• v.34 no.1
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• pp.1-10
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• 1990

Total suspended particulate (TSP) in the atmosphere was collected and size-fractionated by Andersen high volume air sampler for the past two years (Mar. 1987-Feb. 1989) in Seoul. The concentrations of several polycyclic aromatic hydrocarbons and heavy metals were determined to investigate the atmospheric concentrations, seasonal variations and its relationship with the size distribution of suspended particulate matter. The arithmetic mean concentration of total suspended particulate was $229.48\;{\mu}g/m^3$. The concentrations of heavy metals were $2971.94\;ng/m^3$ for Fe, $767.75\;ng/m^3$ for Zn, $765.80\;ng/m^3$ for Pb, $218.40\;ng/m^3$ for Cu, $129.91\;ng/m^3$ for Mn, respectively. And the concentration of PAHs were $3.23\;ng/m^3$ for benzo(a)pyrene, $2.71\;ng/m^3$ for benzo(k)fluoranthene, $4.53\;ng/m^3$ for benzo(ghi)perylene, respectively. The mass-size distribution of TSP was lowest in the particle size range $1.1-3.3\;{\mu}m$ increased as the particle size increased or decreased. But PAHs, Pb and Zn abounded in particles below $2.0\;{\mu}m$, while Fe and Mn abouned in particles above $2.0\;{\mu}m$. TSP and its chemical compositions showed the seasonal variations. The concentrations of anthrophogenic origin like TSP, PAH and heavy metals in the fine particles were highest in winter and lowest in summer. PAH and Ph analyzed showed significant correlations with each other and with TSP concentration in fine particles, indicating that the particles in which they are contained have a similar behavior in the atmosphere.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3651-3656
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• 2012

The size-segregated atmospheric aerosols have been collected at 1100 m site of Mt. Halla in Jeju, a background area in Korea, using 8-stage cascade impact air sampler during Asian dust and non-Asian dust storm periods. Their ionic and elemental species were analyzed, in order to examine the pollution characteristics and composition change between Asian dust and non-Asian dust periods. The major ionic species such as nss-$SO_4{^{2-}}$, $NH_4{^+}$, and $K^+$ were predominantly distributed in the fine particles (below $2.1{\mu}m$ diameter), and besides the $NO_3{^-}$ was distributed more in coarse particle fraction than fine particle. On the other hand, the typical soil and marine species i.e., nss-$Ca^{2+}$, $Na^+$, $Cl^-$, and $Mg^{2+}$, were mostly existed in the coarse particles (over $2.1{\mu}m$ diameter). As well in the elemental analysis of aerosols, the major soil-originated Al, Fe, Ca, and others showed prominently high concentrations in the coarse particle fraction, whereas the anthropogenic S and Pb were relatively high in the fine particle fraction. From the comparison of aerosol compositions between Asian dust and non-Asian dust periods, the concentrations of the soil-originated species such as nss-$Ca^{2+}$, Al, Ca, Fe, Ti, Mn, Ba, Sr have increased as 2.7-4.2 times during the Asian dust periods. Meanwhile the concentrations of nss-$SO_4{^{2-}}$ and $NO_3{^-}$ have increased as 1.4 and 2.0 times, and on the contrary $NH_4{^+}$ concentrations have a little bit decreased during the Asian dust periods. Especially the concentrations of both soil-originated ionic and elemental species increased noticeably in the coarse particle mode during the dust storm periods.