• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.25 no.1
• /
• pp.72-81
• /
• 2015

Objectives: The aim of this study was to investigate the exposure and risk assessment of residents near asbestos mines in Korea. Methods: To assess asbestos types and airborne concentrations, air monitoring was performed in the neighborhoods of Kwangcheon (KC) and Sinsuk (SS) mines, which were leading South Korean mines in the past. In addition, activity-based-sampling (ABS) of residents' particular activities were conducted in order to estimate the Excess Lifetime Cancer Risks (ELCRs) for the residents. Conclusions: The average concentration of airborne asbestos in KC was 0.0014 f/cc and 0.0015 f/cc by PCM and TEM, respectively. In SS it was equal at 0.0012 f/cc by PCM and TEM. No statistically significant difference was found in the average concentration of airborne asbestos between the two mines. The average asbestos concentration of ABS was 0.0048 f/cc (PCM) and 0.0042 f/cc (TEM) in KC, while it was 0.0137 f/cc (PCM) and 0.0125 f/cc (TEM) in SS. It was found that the average asbestos concentration of ABS in SS was statistically significantly higher than that of KC (p<0.01). The results of ELCRs by scenario in KC showed that the scenarios of bicycle, car, weed control, weed whacking, child playing in the dirt, and physical training fell within $1{\times}0^{-6}-1{\times}10^{-4}$, which is the acceptable range of ELCR. The scenarios of motorcycle, walker, digging, and field sweeping, however, exceeded the acceptable range. In SS, only the scenario of car fell within the acceptable range, while all of the other scenarios exceeded the acceptable range.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.21 no.3
• /
• pp.139-145
• /
• 2011

Objectives: This investigation is purposed to evaluate the airborne asbestos concentrations in the public buildings having asbestos containing materials(ACMs) in Seoul. Methods: The Seoul Metropolitan Government carried out an asbestos survey to the city-owned public buildings to identify the level of risk exposure, classified into low, moderate and high risk. To evaluate the airborne concentration of asbestos, 11 sampling sites in ten buildings based on the survey were selected. The air samples from the eleven sites were analyzed by Phase Contrast Microscopy(PCM) and Transmission Electron Microscopy (TEM), and compared the analytical results from the both. Results: 1. The airborne fiber concentrations by PCM were less than the detection limit($7f/mm^2$) in 9(82%) out of 11 sampling sites. The highest concentration was 0.0043 f/cc, but it was below the guideline value for indoor air quality(0.01 f/cc), proposed by the Ministry of Environment, Korea. 2. In two sampling sites, having moderate risk level, the chrysotile was identified and showed it's concentrations of 0.0102 s/cc and 0.0058 s/cc, less than $5{\mu}m$ lengths. 3. The ACMs identified in the two sampling sites were a packing material(65% of chrysotile) in mechanical area and a thermal system insulation(5% of chrysotile) in a boiler room. Having more possibility of asbestos emission in the mechanical area, it would be required to set up and carry out the asbestos management plan. Conclusions: Based on the result of this study, the airborne asbestos concentrations in the public buildings with ACMs were generally lower than the guideline value for indoor air quality. There are widespread concerns about the possible health risk resulting from the presence of airborne asbestos fibers in the public buildings. Most of the previous studies about airborne asbestos analysis in Korea were performed based on PCM method that asbestos and non-asbestos fibers are counted together. In the public and commercial buildings, having ACMs, it is suggested that the asbestos be analyzed by TEM method to identify asbestos due to concerns about asbestos exposure to workers and unspecified people.

• Progress in Medical Physics
• /
• v.27 no.3
• /
• pp.156-161
• /
• 2016

When air discharged from a radioisotope production facility is contaminated with radiation, the public may be exposed to radiation. The objective of this study is to manage such radiation exposure. We measured the airborne radioactivity concentration at a 30 MeV cyclotron radioisotope production facility to assess whether the exhaust gas was contaminated. Additionally, we investigted the radioactive contamination of the air filter for efficient air purification and radiation safety control. To measure the airborne radiation concentration, specimens were collected weekly for 4 h after the beginning of the radioisotope production. Regarding the air purifier, five specimens were collected at different positions of each filter-pre-filter, high-efficiency particulate air filter, and charcoal filter-installed in the cyclotron production room. The concentrations of F-18, I-123, I-131, and Tl-201 generated in the radioiodine production room were $13.5Bq/m^3$, $27.0Bq/m^3$, $0.10Bq/m^3$, and $11.5Bq/m^3$, respectively; the concentrations of F-18, I-123, and I-131 produced in the radioisotope production room were $0.05Bq/m^3$, $16.1Bq/m^3$, and $0.45Bq/m^3$, correspondingly; and those of F-18, I-123, I-131, and Tl-201 generated in the accelerator room were $2.07Bq/m^3$, $53.0Bq/m^3$, $0.37Bq/m^3$, and $0.15Bq/m^3$, respectively. The maximum radiation concentration of I-123 generated in the radioiodine production room was 1,820 Bq/g, which can be disposed after 2 days. The maximum radiation concentration of Tl-202 generated in the radioisotope production room was 205 Bq/g, and this isotope must be stored for 53 days. The I-123 generated in the radioiodine production room had a maximum concentration of 1,530 Bq/g and must be stored for 2 days. The maximum radiation concentration of Na-22 generated in the radioisotope production room was 0.18 Bq/g and this isotope must be disposed after 827 days. To manage the exhaust, the efficiency of air purification must be enhanced by selecting an air purifier with a long life and determining the appropriate replacement time by examining the differential pressure through systematic measurements of the airborne radiation contamination level.

• Journal of Korean Society for Atmospheric Environment
• /
• v.13 no.3
• /
• pp.207-214
• /
• 1997

We collected airborne complex mixtures in a industrial area of Yeochun, and examined whether these complex mixtures could affect gap junctional intercellular communication (GJIC) in a cultured WBF-344 rat liver epithelial cells (LEC). Since the reduction of GJIC plays an important role in chemical carcinogenesis, measurement of changes of GJIC is a meaningful method to screen carcinogenicity of these mixtures. High and low volume samples were dissolved in dimethyl sulfoxide (DMSO) and tested. Blank filter extractions were also examined for exclud-ing possible toxicity of filter itself, and TPA (12-O-tetradecanoylphorbol-13-acetate) and DMSO were used as positive and negative control, respectively. When the cells were exposed to samples at concentration below that required to maintain rather than 85% cell viability based on the result of neutral red uptake assay, maximal inhibition of GJIC was observed at 1hr after treatment with both high and low volume samples by scrape-loading dye transfer assay. In fluorescence recovery after photobleaching assay, recovery rates via gap junctions were 33%/min in high volume sample and 62%/min in low volume sample. In together, airborne samples collected in Yeochun inhibited GJIC in a cultured WBF-344 rat LEC. These results suggest airborne samples tested in this experiment may attribute to cause a certain type and degree of cancers in in vivo when exposured for some periods.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.15 no.2
• /
• pp.124-134
• /
• 2005

To investigate the exposure effect of polynuclear aromatic hydrocarbons (PAHs), we measured airborne total PAHs as an external dose, urinary 1-hydroxypyrene (1-OHP) as an internal dose of PAHs exposure, and analyzed the relationship between urinary 1-OHP concentration and PAHs exposure. The study population contained 44 workers in steel-pipe coating and paint manufacture industries. The airborne PAHs was obtained during survey day, and urine were sampled at the end of shift. Personal information on age, body weight, height, eniployment duration, smoking habit, and alcohol consumption was obtained by a structured questionnaire. Airborne PAHs were analyzed by the gas chromatograph with mass selective detector. Urinary 1-OHP levels were analyzed by the high performance liquid chromatograph with ultraviolet wavelength detector. For statistical estimation, t-test, ${\chi}^2$-test, analysis of variance, correlation analysis, arid regression analysis were executed by SPSS/PC (Windows version 10). The mean of environmental total PAHs was $87.8{\pm}7.81{\mu}g/m^3$. The mean concentration ($526.5{\pm}2.85{\mu}g/m^3$) of workers in steel-pipe coating industries using coal tar enamel was the higher than that ($17.5{\pm}3.36{\mu}g/m^3$) of workers in paint manufacture industries using coal tar paint. The mean of urinary 1-OHP concentration ($51.63{\pm}3.144{\mu}\;mol/mol$ creatinine) of workers in steel-pipe coating industries was the higher than that ($2.33{\pm}4.709{\mu}\;mol/mol$ creatinine) of workers in paint manufacture industries. The mean of urinary 1-OHP concentration of smokers was the higher than that of non-smokers. There was significant correlation between the urinary concentration of 1-OHP and the environmental concentration of PAHs (r=O.S48, p<0.001), pyrene(r=0.859, p<0.001), and urinary cotinine (r=0.324, p<0.05). The regression equation between the urinary concentration of 1-OHP in ${\mu}g/g$ creatinine($C_{1-OHP}$) and airborne concentration of PAHs (or pyrene) in ${\mu}g/m^3$ ($C_{PAHs}$ or Cpyrene) is: Log ($C_{1-OHP}$)=-0.650+0.889×Log($C_{PAHs}$), where $R^2=0.694$ and n=38 for p<0.001.Log ($C_{1-OHP}$)=1.087+0.707${\times}$Log(Cpyrene), where $R^2=0.713$ and n=38 for p<0.001. From the results of stepwise multiple regression analysis about 1-OHP, significant independents were total PAHs and urinary cotinine (adjusted $R^2=0.743$, p<0.001). In this study, there were significant correlation between the urinary concentration of 1-OHP and the airborne concentration of PAHs. The urinary 1-OHP was effective index as a biomarker of airborne PAHs in workplace. But it was influenced by non-occupational PAHs source, smoking.

• 보존과학연구
• /
• s.36
• /
• pp.64-73
• /
• 2015

The temple and family or private owner have managed the storage space of movable cultural properties. Thus they lack the ability to manage professionally and systematically, movable cultural properties are in a poor environment and have been damaged by abundant dust and airborne fungi in the storage. In this study, we investigated microbes distribution in 10 storage or exhibition hall housing the movable cultural properties. As a results, concentration of collected microorganisms exhibited a large difference according to a storage and the D Relic Museum in Yeongam is the most contaminant storage, in which detected $2,000m^3$ or more. More than $166m^3$ of the fungi were detected in most storages of the other. We identified so many varieties of fungi such as Aspergillus sp., Penicillium sp., Alternaria sp. and Cladosporium sp. existing commonly in 10 storages including wood rot fungi such as Ceriporia lacerata, Ganoderma carnosum, Myrothecium gramineum and Bjerkandera sp.. This airborne fungi may damage cultural heritages. The Guideline on a concentration of airborne fungi should be estimated and management system to the preservation environment must be provided.

• Journal of the Society of Disaster Information
• /
• v.19 no.2
• /
• pp.344-351
• /
• 2023

Purpose: This study aimed to evaluate the effectiveness of a dielectric barrier discharge (DBD) plasma module for sterilizing airborne bacteria in indoor spaces and measure the concentration of ozone generated during plasma discharge. Method: The DBD plasma module was installed in a 76m³ space, and air samples were collected under various discharge times to compare the reduction of airborne bacteria. Result: The results showed a significant decrease in airborne bacteria, ranging from 92.057% to 99.999%, with an average ozone concentration of 0.04 ppm, below the reference value. Conclusion: The study suggests that plasma discharge can be used as a means of preventing the spread of airborne bacteria and viruses, while ensuring safety for human exposure.

• Journal of Environmental Health Sciences
• /
• v.30 no.3
• /
• pp.259-263
• /
• 2004

This study was performed to investigate airborne formaldehyde concentration in preschool facilities. Arithmetic mean of indoor formaldehyde concentration in urban area was 34.9 ppb(Geometric mean 24.4 ppb) whereas outdoor concentration was 21.5 ppb(GM 11.9 ppb). In rural area, formaldehyde concentrations were 36.4 ppb(GM 28.7 ppb), 4.1 ppb(GM 4.1 ppb), respectively. There is no statistical significance between the formaldehyde concentrations of urban classrooms and those of rural area. We verified that the distribution of airborne formaldehyde concentration was log-normal characteristic using Shapiro and Wilk test. The 6.7% of urban indoor samples was exceeded the domestic standard limit of indoor air quality. From our study and other study, we concluded that the major emission sources of formaldehyde in preschool facilities was in indoor rather than outdoor.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.26 no.2
• /
• pp.219-224
• /
• 2016

Objectives: Lung cancer occurred with worker working in an urban bus garage. A survey was conducted to investigate whether lung cancer had causal relationship with work. Exposure to asbestos and diesel engine exhaust were suspected. Methods: Airborne asbestos was sampled on membrane filter and analyzed using phase-contrast microscopy. Airborne diesel exhaust was sampled using quartz filter and analyzed with thermal-optical analyzer. Polynuclear aromatic hydrocarbons was sampled using PTFE filter and XAD-2 tube and analyzed with gas chromatography-mass selective detector. Results: Airborne asbestos concentration was under 0.01 fiber/cc. Worker who warmed up an engine of urban bus for 2 hours was exposed to elemental carbon concentration, $15.5{\mu}g/m^3$. Only naphtalene among polynuclear aromatic hydrocarbons was detected. Conclusions: It was difficult to conclude about worker exposure to asbestos because working hour related asbestos was too short. In reviewing papers, the exposure to asbestos over 0.01 fiber/cc during exchange brake lining was found. It was identified that worker's occupational exposure to diesel exhaust based on elemental carbon was higher than the other occupational exposure to diesel exhaust.

• Journal of Species Research
• /
• v.4 no.2
• /
• pp.159-168
• /
• 2015

Although airborne pollen is invisible to the eye, it has been known as a major source to respiratory allergic reactions. For this reason, airborne pollen is monitoring in many countries to predict pollen concentration based on locality and season. However, the morphological characteristics of airborne pollen and their potential tendency as an allergen are still obscure. In the present study, we selected 52 airborne pollen samples based on previously reported data and investigated their detail pollen characteristics using LM and SEM. Major airborne pollen in Korea has sorted in 19 families (most angiosperms except four gymnosperm families), and all pollen grains are small to medium in size ($P=17.34-49.86{\mu}m$) apart from the bisaccate pollen grains of Pinaceae ($P=46.49-106.20{\mu}m$). The aperture number and shape vary from sulcate to polyporate. While the inaperture pollen has found only in gymnosperm (Cupressaceae and Taxaceae), triporate or polyporate is common pollen type in angiosperm. The sexine ornamentations could divide into several types, but the most sculpturing types are inconspicuous like psilate, rugulate and granulate. Reticulate pollen grains as a semitectum have occurred the species of genera Platanus and Fraxinus only. To estimate the possible relationships between pollen features and allergen, the results are discussed in botanical context.