• Proceedings of the Korea Air Pollution Research Association Conference
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• 2008.10a
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• pp.277-278
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• 2008

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2010.04a
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• pp.642-643
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• 2010

• Journal of Environmental Health Sciences
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• v.37 no.1
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• pp.57-63
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• 2011

Crocidolite quality control (QC) sampling created by the wet generation method has been validated by validation tests such as the accuracy, precision, and storage tests. For this study we designed and developed a manufacturing apparatus and standard operating procedure for making these QC samples. The most important step in the procedure of making QC samples was the stage eliminating static electricity in asbestos fibers. This static electricity hampers the fibers clog functioning. In accuracy and precision tests by phase contrast microscopy analysis, the difference between the reference values and the studied values was at maximum 17.8%. This satisfies the AIHA proficiency analytical test criteria for asbestos. We could confirm the nearly even distribution of crocidolite fibers on the membrane filter. Also, there was no loss of fibers in the storage test after the one month.

• Journal of odor and indoor environment
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• v.17 no.4
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• pp.322-329
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• 2018

The objective of this study is to identify the research trend in the field of indoor environment in Korea. We collected 419 papers published in the Journal of the Korean Society for indoor environment between 2004 and 2018, and attempted to produce datasets using a topic modeling technique, Latent Dirichlet Allocation(LDA). The result of topic modeling showed that 8 topics ("VOCs investigation", "Subway environment", "Building thermal environment", "School health", "Building particulate matter", "Asbestos risk", "Radon risk", "Air cleaner and treatment") could be extracted using Gibbs sampling method. In terms of topic trends, investigation of volatile organic compounds, subway environment, school health, and building particulate matter showed a decreasing tendency, while the building thermal environment, asbestos risk, radon risk, air cleaners, and air treatment showed an increasing tendency. The results of this topic modeling could help us to understand current trends related indoor environment, and provide valuable information in developing future research and policy frameworks.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.290-295
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• 2000

Mechanical and physical properties of wood fiber for the reinforcement of thin-sheet cement products were investigated. The slurry-dewatering method followed by pressing was used to manufacture the products. Mechanical and physical properties of wood fiber reinforced cement composites were assessed with flexural strength, density, and water absorption. The results obtained in this study were analyzed statistically using the analysis of variance in order to derive statistically reliable conclusions.

• Journal of Preventive Medicine and Public Health
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• v.23 no.1 s.29
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• pp.77-86
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• 1990

Between 1977 and 1987, 20 patients with mesothelioma were treated at Severance Hospital. Data was gathered from medical charts at the time of hospitalization of mesothelioma patients and from a follow-up questionnaire by mail or telephone. The results acquired were as follows : 1. Among the 20 patients, 11 men and 9 women with mesothelioma were identified. The mean age at hospitalization was 47 years and 11 mesothelioma patients were known or presumed to be dead during the different observation periods. 2. Only one mesothelioma patient had a definite history of occupational asbestos exposure. 3. The sites of origin of mesothelioma were the pleura(13), peritoneum(2), pericardium(2), mediastinum (2), and pelvis(1). Common symptoms included dyspnea, chest pain, abdominal distension, etc. 4. Pathologically, mesotheliomas were divided into 14 malignant types and 6 benign types ; and histologically, 8 fibrous mesotheliomas and 3 epithelial mesotheliomas were shown. 5. There was a statistically significant difference in survival rate according to pathologic type and smoking status. In the groups with malignant mesothelioma, 50% survival time from first symptoms was 18 months and that from diagnosis was 11 months. Also, 75% survival time from diagnosis was 6 months in the smoking groups and 19 months in the non-smoking groups.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.569-579
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• 2011

This study evaluated the indoor air quality of 26 government offices located in Seoul. The pollutant samples were taken from Jan. 13th to Jan. 29th and Feb. 20th to Feb. 23rd, 2010 in the offices. The target indoor pollutants for this study were $PM_{10}$, formaldehyde, carbon monoxide, carbon dioxide, total bacteria counts, total volatile organic compounds, radon, nitrogen dioxide, ozone, and asbestos which were controlled by the indoor air quality law for the multiple-use facilities management. The results of this study showed that some pollutants of the 38.5% offices exceeded the standards of the air quality guideline. The correlation analysis of the same pollutants between indoor and outdoor represented that $NO_2$ (r=0.629, p<0.05) and $O_3$ (r=0.459, p<0.01) were significant, however, $PM_{10}$ and CO were not. The correlation analysis between different pollutants showed that CO and TVOC (total volatile organic compounds: r=0.724; p<0.01), CO and $NO_2$ (r=0.674; p<0.01), HCHO and humidity (r=0.605; p<0.01), $CO_2$ and TVOC (r=0.534; p<0.01), TBC (total bacteria counts) and Asbestos (r=0.520; p<0.01) were significant. The energy-saving system of government buildings in winter caused under-ventilated and poor air quality. This study suggests that the concentrations of radon and $CO_2$ should be used as an indicator for monitoring indoor air quality and maintaining effective ventilations.

• Safety and Health at Work
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• v.8 no.3
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• pp.258-266
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• 2017

Background: Welders are exposed to many known and suspected carcinogens. An excess lung cancer risk among welders is well established, but whether this is attributable to welding fumes is unclear. Excess risks of other cancers have been suggested, but not established. We investigated welding cancer risks in the population-based Canadian Census Health and Environmental Cohort. Methods: Among 1.1 million male workers, 12,845 welders were identified using Standard Occupational Classification codes and followed through retrospective linkage of 1991 Canadian Long Form Census and Canadian Cancer Registry (1992-2010) records. Hazard ratios (HRs) were calculated using Cox proportional hazards models based on estimated risks of lung cancer, mesothelioma, and nasal, brain, stomach, kidney, and bladder cancers, and ocular melanoma. Lung cancer histological subtypes and risks by industry group and for occasional welders were examined. Some analyses restricted comparisons to blue-collar workers to minimize effects of potential confounders. Results: Among welders, elevated risks were observed for lung cancer [HR: 1.16, 95% confidence interval (CI): 1.03-1.31], mesothelioma (HR: 1.78, 95% CI: 1.01-3.18), bladder cancer (HR: 1.40, 95% CI: 1.15-1.70), and kidney cancer (HR: 1.30, 95% CI: 1.01-1.67). When restricted to blue-collar workers, lung cancer and mesothelioma risks were attenuated, while bladder and kidney cancer risks increased. Conclusion: Excess risks of lung cancer and mesothelioma may be partly attributable to factors including smoking and asbestos. Welding-specific exposures may increase bladder and kidney cancer risks, and particular sources of exposure should be investigated. Studies that are able to disentangle welding effects from smoking and asbestos exposure are needed.

• Journal of Environmental Health Sciences
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• v.43 no.4
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• pp.273-279
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• 2017

Objectives: Carbon nanotubes (CNTs) are next-generation industrial nanoparticles which possess excellent mechanical strength along with good thermal conductivity and electric properties. Given these characteristics, carbon nanotubes are being widely applied in various fields, including research and development. However, concerns have been raised over hazardous properties due to their similar fiber shape to asbestos. Recent studies have shown that CNTs pose potential hazards which may cause fibrosis and/or lung inflammation similarly to asbestos. Methods: After intratracheal instillation of SWCNTs and MWCNTs to rats, pulmonary surfactant (PS) of the SWCNTs and MWCNTs was measured and analyzed using bronchoalveolar lavage fluid collected from the lung. After a single intratracheal instillation of SWCNTs and MWCNTs, phospholipid predominantly showed a significant increase compared to the control group, while proteins exhibited a significant increase both three days and one week after instillation. Results: As a result of surface tension, MWCNTs showed a significant decrease three days after treatment compared to the control group. In the case of the total cell number three days after instillation, MWCNTs revealed a temporarily significant increase when compared to the control group. For PMN number, when compared to the control group, SWCNTs displayed a significant increase throughout the observation period, while MWCNTs showed a significant increase three days and three months after treatment. Conclusions: After exposure to CNTs, the total cell number and PNT number, which indicate inflammatory response, were significantly increased. Therefore, this study suggests fiber-shaped CNTs may have a harmful effect on the lungs.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.151-154
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• 2014

Background: Lung cancer is the most common cause of cancer-related death worldwide. The incidence of lung cancer is aproximately 7-8 thousand percent in Turkish women. In this study, we aimed to evaluate the clinical, pathological properties and survival data of female patients with lung cancer who were treated in our center. Materials and Methods: From 2007 to 2012, 50 women with lung cancer were enrolled. Patient data were evaluated retrospectively. Results: The median age was 61 (40-81). Forty patients (80%) were diagnosed with non small cell lung cancer (NSCLC), 10 patients (20%) were small cell carcinoma (SCC). Twelve (24%) patients were smokers and 13 of 16 non-smokers had a history of exposure to asbestos. The most common histologic subtype was adenocarcinoma (46%) and this accounted for 71% in patients with exposure to asbestos. The most common initial Eastern Cooperative Oncology Group (ECOG) performance score was 1 (24 patients, 48%) and initial stage was IV (25 patients, 50%) in the study group. During the median 15 months (1-96 months) followup period: 1 year overall survival (OS) was 68%, 2year overall survival was 36% and the median survival time was 19 months. According to univariate analysis, poor ECOG performance status, advanced stage, anemia and weight loss at time of diagnosis were negative prognostic factors. However, adenocarcinoma sub-type was a positive prognostic factor. Conclusions: In this study NSCLC sub-type, poor ECOG performance score, advanced stage, anemia and weight loss were prognostic factors in Turkish women with lung cancer.