• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.1
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• pp.75-86
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• 2020

Objectives: In this study, we assessed respiratory hazards in the working environment as the work-relatedness of occupational diseases were examined. Methods: The subjects of the study were three Korean meat roasting restaurants, one Chinese restaurant, and two cafeterias. Measurement items were total dust, respirable dust, fine dust (PM_2.5), PAHs, TVOCs, temperature, humidity, carbon monoxide, carbon dioxide, and nitrogen dioxide. Results: The concentration of total dust and respiratory dust in the restaurant was low. Most PAHs were undetectable, but some Napthalene and Acenaphthylene was detected. Thirteen kinds of PAHs were detected in one sample of roasted meat, and Benzo(a)pyrene was 1.496 ㎍/㎥. PM_2.5, TVOCs, CO, and CO₂ were instantaneously high, but the average concentration was low. NO₂ was not detected. Conclusions: The results show that harmful substances such as PM_2.5, PAHs, CO, and TVOCs were generated in the air in the catering industry. When roasting meat, Benzo(a)pyrene, a carcinogen related to lung cancer, was generated among PAHs. Lung cancer can occur when working for a long time in such a working environment. Therefore, it is necessary to improve the working environment for the health of restaurant workers, and it is necessary to evaluate the concentration of harmful substances by cooking method through further research.

• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.119-129
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• 2003

Concrete and steel are essential structural materials in the construction. But, concrete, different from steel, consists of many materials and is affected by many factors such as properties of materials, site environmental situations, and skill of constructors. Concrete have two kinds of properties, immediately knowing properties such as slump, air contents and time dependent one like strength. Therefore, concrete mixes depend on experiences of experts. However, at point of time using High Performance Concrete, new method is wanted because of more ingredients like mineral and chemical admixtures and lack of data. Artificial Neural Networks(ANN) are a mimic models of human brain to solve a complex nonlinear problem. They are powerful pattern recognizers and classifiers, also their computing abilities have been proven in the fields of prediction, estimation and pattern recognition. Here, among them, the back propagation network and radial basis function network ate used. Compositions of high-performance concrete mixes are eight components(water, cement, fine aggregate, coarse aggregate, fly ash, silica fume, superplasticizer and air-entrainer). Compressive strength, slump, and air contents are measured. The results show that neural networks are proper tools to minimize the uncertainties of the design of concrete mixtures.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.500-507
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• 2019

Objectives: The purpose of this study is to categorize farm types and analyze the cultivated area and labor input time for each crop over a year in order to decide farm type conducting for the hazard exposure assessment. Methods: Crops ranked within the top 45 by cultivated area in Korea were selected and 15 target crops that exposure assessment had been conducted for through the Rural Development Administration(RDA) pilot research projects were selected. Labor input time was based on data investigated through RDA research surveillance. If there was no data, data from Statistics Korea was used. Data from Statistics Korea was used for total cultivated area. Results: Crops were divided into 5 types: open field crops(Chinese cabbage, Corn, Ginger, Potato), fruits (Mandarin, Pear), green house crops(Cucumber, Lily, Oriental melon, Pumpkin, Tomato), livestock(Poultry), specialty crops(Ginseng, Oyster mushroom, Tobacco). The cultivated area for potato was the largest, and lily was the smallest among the crops. Labor input time over a year was the highest with oyster mushroom and the lowest with pear. Total labor input time by crops was the highest with mandarin and the lowest with Chinese cabbage. Conclusions: To evaluate hazard factors of farm work, it's essential that crops and tasks be classified based on the size of farmers and working hours by farm type. Therefore, the priority of management should be determined based on the cultivated area and total labor time, but the characteristics of tasks in each crop should also be considered.

• Korean Journal of Radiology
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• v.24 no.6
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• pp.590-598
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• 2023

Objective: To investigate whether the levels of inflammation detected by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) can predict disease relapse in immunoglobulin G4-related disease (IgG4-RD) patients receiving standard induction steroid therapy. Materials and Methods: This prospective study analyzed pretherapy FDG PET/CT images from 48 patients (mean age, 63 ± 12.9 years; 45 males and 3 females) diagnosed with IgG4-RD between September 2008 and February 2018, who subsequently received standard induction steroid therapy as the first-line treatment. Multivariable Cox proportional hazards models were used to identify the potential prognostic factors associated with relapse-free survival (RFS). Results: The median follow-up time for the entire cohort was 1913 days (interquartile range [IQR], 803-2929 days). Relapse occurred in 81.3% (39/48) patients during the follow-up period. The median time to relapse was 210 days (IQR, 140-308 days) after completion of standardized induction steroid therapy. Among the 17 parameters analyzed, Cox proportional hazard analysis identified whole-body total lesion glycolysis (WTLG) > 600 on FDG-PET as an independent risk factor for disease relapse (median RFS, 175 vs. 308 days; adjusted hazard ratio, 2.196 [95% confidence interval: 1.080-4.374]; P = 0.030). Conclusion: WTLG on pretherapy FDG PET/CT was the only significant factor associated with RFS in IgG-RD patients receiving standard steroid induction therapy.

• Journal of Environmental Health Sciences
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• v.48 no.3
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• pp.183-194
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• 2022

Background: No study has examined the regulatory factors associated with fatal health problems due to the use of humidified disinfectants (HD) in South Korea. Objectives: This study aimed to identify and discuss the deficiencies and limitations found in the Toxic Chemical Control Acts (TCCA) that failed to prevent the health risk of chemicals in HD products. Methods: The South Korean TCCA was reviewed focusing on acts in operation from 1994 through the end of 2011, the period when HD was allowed in manufacturing and marketing. Results: The TCCA was the act intended to regulate the toxicity of chemicals in HD products. We found the TCCA to lack three key legal clauses which would have been essential to controlling the health risk of HD. First, there was the exemption of toxic and hazard testing for existing chemicals, including chloromethylisothiazolinone (CMIT), methylisothiazolinone (MIT), and benzalkonium chloride (BKC). Secondly, there were no articles requiring industry to provide animal inhalation test result for polymers such as polyhexamethylene guanidine (PHMG) and Oligo(2-)ethoxyethoxyethyl guanidine chloride (PGH). Finally, there was a lack of articles on examining the risk of products as well as on addressing changes in the usage of products. These articles were found to be generally provided in the US Toxic Substance Chemical Act (TSCA) and the EU Registration, Evaluation and Authorization of Chemicals (REACH). Conclusions: In conclusion, the Ministry of Environment of South Korea had not updated key articles for regulating hazardous chemicals, causing large-scale health problems due to HD which had been fundamentally addressed in chemical-related acts in other countries.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1237-1245
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• 2018

In this study, the contamination levels of hygienic indicators and foodborne pathogens in retail meat products were investigated in relation to the various market factors including processing temperature, processing area, and market type. Ground beef samples (n=80) were purchased from 40 meat markets and investigated for microbiological quality. Beefs processed below $20^{\circ}C$ had significantly lower numbers of total coliforms (TC) than these processed over $20^{\circ}C$ (2.01 vs. 2.79 log CFU/g; p<0.05). Interestingly, separation of processing area did not affect the contamination levels. Remarkably, the contamination levels of hygienic indicator differ among market types, indicating that not only processing condition but distribution structure that is directly related with storage period could affect the final microbiological loads of the meat products. In addition, the prevalences of Listeria monocytogenes (a psychrotroph), Enterococcus faecium, and Enterococcus faecalis were 7.5% (6/80), 10.0% (8/80), and 20.0% (16/80), respectively, which is irrelevant to market factors except meat products from wholesale markets where no L. monocytogenes were found among 30 samples. The results of this study indicate that the contamination level of hygiene indicator and foodborne pathogens in retail beef is more related with processing temperature and storage period than other environmental factors.

• Journal of Engineering Education Research
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• v.25 no.2
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• pp.42-56
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• 2022

This study aimed to investigate the views of STEM college students on the social responsibility of scientists and engineers. A total of 660 students in STEM majors at several Korean universities participated in the study. We assessed social responsibility among college students in STEM majors using the VSRoSE scale, which taps into eight different domains of social responsibility: Concern for human welfare and safety (HUMAN), Concern for environmental sustainability (ENVIR), Consideration of societal risks and consequences (CONSEQ), Consideration of societal risks and consequences (CONSEQ), Consideration of societal needs and demands (NEEDS), Pursuit of the common good (COMGOOD), Civic engagement and services (CIVIC), Communication with the public (COMMU), and Participation in policy decision-making (POLICY). Group differences in social responsibility by gender, majors, and years in school were examined. Mean scores in HUMAN, ENVIR, and CONSEQ were relatively higher than those in NEEDS, COMGOOD, CIVIC, COMMU, and POLICY. Cluster analysis identified five different groups with similar patterns of social responsibility scores. In addition to two groups with overall high and low scores across all eight factors of VSRoSE, three additional groups with different combinations of high and low scores in different factors were identified. The results indicated that students with low social responsibility are not homogeneous and these heterogeneous sub-groups of students will need tailored interventions highlighting different factors of social responsibility that they lack. Pedagogical implications of social responsibility for education were discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.4B
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• pp.261-266
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• 2012

In this study, soil environmental impact assessment using risk-based approach was compared with that using concentration-based approach. For this, heavy metal contaminant exposure was characterized in an abandoned mine area. According to the estimated carcinogenic and non-carcinogenic risks, soil ingestion was identified as the most dominant exposure pathway. When contaminant concentrations exceeded the Korean Soil Contamination Warning Standards, their corresponding risk values also exceeded the Total Soil Risk Standard. Even the cases of satisfying the Korean Soil Contamination Warning Standards mostly showed higher risk levels than the Total Soil Risk Standard, re-confirming a more sensitivity of the risk-based assessment than concentration-based assessment. However, the in-depth analysis of the estimated non-carcinogenic risk values revealed a few cases for soil contact pathway showing contaminant concentrations higher than the Korean Soil Contamination Warning Standards although their non-carcinogenic risk values satisfied the level of Hazard Index Standard. The findings from this study support a necessity of shifting policy paradigm from concentration-based approach into risk-based approach for reliable risk assessment in abandoned mine areas, and also suggest a necessity of further fundamental studies regarding risk factors and standards.

• Journal of Environmental Health Sciences
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• v.41 no.6
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• pp.412-424
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• 2015

Objectives: An ultra dry air environment of nearly ${\leq}2%$ RH is often required in lithium battery factories. The objective of this study is to evaluate the subjective eye, pulmonary, nose, and skin symptoms of workers exposed to ultra-low relative humidity and thionyl chloride. Methods: We recruited 274 workers using a self-reported questionnaire in March 2014. Those who worked in ultra-low relative humidity and with thionyl chloride were identified and their prevalence of symptoms was compared with that of other workers. We excluded white collar workers, researchers and other workers who were exposed to various hazard factors, and finally included 164 workers. Results: There were significant differences in the rate of self-reported eye and skin symptoms between exposure group_1 and exposure group_2. Exposure group_2 experienced more frequent eye, and skin symptoms. Multinomial logistic regression analysis for experience of dry eye symptoms and skin symptoms in exposure group_2 showed that dry eye symptoms (odds ratio [OR], 6.33, 95% confidence interval [CI], 2.19-18.24, p<0.001), and itchiness (OR, 6.45, 95% CI, 1.94-21.43, p<0.01) were the significant variables. The complaints of workers experiencing ultra-low relative humidity and thionyl chloride were high compared with other workers. Conclusion: These findings suggest that exposure to ultra-low relative humidity and thionyl chloride may be associated with more frequent eye and skin symptoms than exposure to ultra-low relative humidity alone. The current precautions to protect workers from the adverse effects of ultra-low relative humidity and thionyl chloride appear to be insufficient, indicating that additional management plans to reduce symptoms should be considered.

• Safety and Health at Work
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• v.15 no.1
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• pp.87-95
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• 2024

Background: This study focuses on assessing occupational risk for the health hazards encountered during maintenance works (MW) in semiconductor fabrication (FAB) facilities. Objectives: The objectives of this study include: 1) identifying the primary health hazards during MW in semiconductor FAB facilities; 2) reviewing the methods used in evaluating the likelihood and severity of health hazards through occupational health risk assessment (OHRA); and 3) suggesting variables for the categorization of likelihood of exposures to health hazards and the severity of health effects associated with MW in FAB facilities. Methods: A literature review was undertaken on OHRA methodology and health hazards resulting from MW in FAB facilities. Based on this review, approaches for categorizing the exposure to health hazards and the severity of health effects related to MW were recommended. Results: Maintenance workers in FAB facilities face exposure to hazards such as debris, machinery entanglement, and airborne particles laden with various chemical components. The level of engineering and administrative control measures is suggested to assess the likelihood of simultaneous chemical and dust exposure. Qualitative key factors for mixed exposure estimation during MW include the presence of safe operational protocols, the use of air-jet machines, the presence and effectiveness of local exhaust ventilation system, chamber post-purge and cooling, and proper respirator use. Using the risk (R) and hazard (H) codes of the Globally Harmonized System alongside carcinogenic, mutagenic, or reprotoxic classifications aid in categorizing health effect severity for OHRA. Conclusion: Further research is needed to apply our proposed variables in OHRA for MW in FAB facilities and subsequently validate the findings.