• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2018년도 춘계 종합학술대회 논문집
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• pp.409-410
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• 2018

Background: Asthma is one of the most common chronic diseases and can be affected by environmental factors. It has been reported that exposure to indoor environmental factors can cause infantile asthma during infancy and childhood, but the previous studies are not yet clear. Climate change has recently been shown to increase indoor mold. Exposure to fungi is known to be directly related to the development of aggravation. Methods: This study was conducted from July 20, 2016 to September 30, 2016. The study was conducted on 90 household with children under the age of 7 who attend atopy school. The questionnaire surveyed allergic symptoms, social and demographic characteristics, and environmental characteristics. Environmentally hazardous substances were measured such as temperature, humidity, fine dust, volatile organic compounds, formaldehyde, bacteria, fungus, house dust mite, endotoxin. Results: According to the survey results, 9 patients (10%) were treated with asthma, 6 (6.7%) were asthmatic patients during the past 12 months, and 4 patients (4.4%) were asthmatic patients during the past 12 months. There were statistically significant differences in the direct effect of smokers in the family (P=0.0328). High-filter vacuum cleaners collected $0.4222CFU/m^3$ in subjects without asthma, and $0.2222CFU/m^3$ in subjects with asthma. In addition, various results confirmed that asthma exacerbated by mold exposure. Conclusions: The results of this study suggest that exposure to fungal by infants and toddlers may play an important role in the development of asthma. In this study, we investigated the relationship between asthma and fungal concentration.

• 한국산업보건학회지
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• 제26권1호
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• pp.1-10
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• 2016

Objectives: The aim of this study is to review the results of exposure to chemicals and to extremely low frequency(ELF) magnetic fields generated in wafer fabrication operations in the semiconductor industry. Methods: Exposure assessment studies of silicon wafer fab operations in the semiconductor industry were collected through an extensive literature review of articles reported until the end of 2015. The key words used in the literature search were "semiconductor industry", "wafer fab", "silicon wafer", and "clean room," both singly and in combination. Literature reporting on airborne chemicals and extremely low frequency(ELF) magnetic fields were collected and reviewed. Results and Conclusions: Major airborne hazardous agents assessed were several organic solvents and ethylene glycol ethers from Photolithography, arsenic from ion implantation and extremely low frequency magnetic fields from the overall fabrication processes. Most exposures to chemicals reported were found to be far below permissible exposure limits(PEL) (10% < PEL). Most of these results were from operators who handled processes in a well-controlled environment. In conclusion, we found a lack of results on exposure to hazardous agents, including chemicals and radiation, which are insufficient for use in the estimation of past exposure. The results we reviewed should be applied with great caution to associate chronic health effects.

• Safety and Health at Work
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• 제9권3호
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• pp.290-295
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• 2018

Background: There is little information on the dose-response relationship between exposure to occupational carcinogenic agents and mesothelioma. This study aimed to investigate this association as well as the existence of agents other than asbestos that might cause mesothelioma. Methods: The Swedish component of the Nordic Occupational Cancer (NOCCA) study consists of 6.78 million individuals with detailed information on occupation. Mesothelioma diagnoses recorded in 1961-2009 were identified through linkage to the Swedish Cancer Registry. We determined cumulative exposure, time of first exposure, and maximum exposure intensity by linking data on occupation to the Swedish NOCCA job-exposure matrix, which includes 29 carcinogenic agents and corresponding exposure for 283 occupations. To assess the risk of mesothelioma, we used conditional logistic regression models to estimate hazard ratios and 95% confidence intervals. Results: 2,757 mesothelioma cases were identified in males, including 1,416 who were exposed to asbestos. Univariate analyses showed not only a significant excess risk for maximum exposure intensity, with a hazard ratio of 4.81 at exposure levels 1.25-2.0 fb/ml but also a clear dose-response effect for cumulative exposure with a 30-, 40-, and 50-year latency time. No convincing excess risk was revealed for any of the other carcinogenic agents included in the Swedish NOCCA job-exposure matrix. Conclusion: When considering asbestos exposure, past exposure, even for short periods, might be enough to cause mesothelioma of the pleura later in life.

• Safety and Health at Work
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• 제8권3호
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• pp.315-317
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• 2017

We present the case of a 45-year-old man with a history of benzene exposure who developed splenic marginal zone lymphoma. For 6 years, he had worked in an enclosed space cleaning instruments with benzene. He was diagnosed with splenic marginal zone lymphoma 19 years after retirement. During his time of working in the laboratory in the 1980s, working environments were not monitored for hazardous materials. We indirectly estimated the cumulative level of past benzene exposure using job-exposure matrices and technical assumptions. Care must be taken in investigating the relevance of occupational benzene exposure in the occurrence of indolent B-cell lymphoma. Because of the long latency period and because occupational measurement data do not exist for the period during the patient's exposure, the epidemiological impact of benzene exposure may be underestimated.

• 환경영향평가
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• 제20권6호
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• pp.891-905
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• 2011

Climate vulnerability index is usually defined as a function of the climate exposure, sensitivity, and adaptive capacity, which requires adequate selection of proxy variables of each variable. We selected and used 9 proxy variables related to climate exposure in the literature, and diagnosed the adequacy of them for application in Korean peninsula. The selected proxy variables are: four variables from temperature, three from precipitation, one from wind speed, and one from relative humidity. We collected climate data over both previous year (1981~2010) and future climate scenario (A1B scenario of IPCC SERES) for 2020, 2050, and 2100. We introduced the spatial and temporal diagnostic statistical parameters, and evaluated both spatial and time variabilities in the relative scale. Of 9 proxy variables, effective humidity indicated the most sensitive to climate change temporally with the biggest spatial variability, implying a good proxy variable in diagnostics of climate change vulnerability in Korea. The second most sensitive variable is the frequency of strong wind speed with a decreasing trend, suggesting that it should be used carefully or may not be of broad utility as a proxy variable in Korea. The A1B scenario of future climate in 2020, 2050 and 2100 matches well with the extension of linear trend of observed variables during 1981~2010, indicating that, except for strong wind speed, the selected proxy variables can be effectively used in calculating the vulnerability index for both past and future climate over Korea. Other local variabilities for the past and future climate in association with climate exposure variables are also discussed here.

• Safety and Health at Work
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• 제2권2호
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• pp.87-96
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• 2011

In 1967, the problem of occupational lead exposure came to public attention in Korea. Since then, regular progress has been made in lowering workplace lead exposures, instituting new workplace controls, and implementing health examinations of exposed workers. Past serious lead poisoning episodes made it possible to introduce biological monitoring programs on a voluntary basis in high-lead-exposure facilities in Korea. Industry-specific occupational health services for lead workers in Korea during the last 22 years can be categorized into three phases. During the first phase (1988-1993), efforts were directed at increasing awareness among workers about the hazards of lead exposure, biological monitoring of blood zinc protoporphyrin began, and a respiratory protection program was introduced. During the second phase (1994-1997), a computerized health management system for lead workers was developed, blood-lead measurement was added to biologic monitoring, and engineering controls were introduced in the workplace to lower air-lead levels to comply with air-lead regulations. Finally, during the third phase (1998-present), a new biomarker, bone-lead measurement by X-ray fluorescence, was introduced. Bone-lead measurement proved to be useful for assessing body burden and to demonstrate past lead exposure in retired workers. Occupational health service practice for lead workers, including the industry-specific group occupational health system, has brought considerable success in the prevention of lead poisoning and in reducing the lead burden in Korean lead workers during the last several decades. The successful achievement of prevention of lead poisoning in Korea was a result of the combined efforts of lead workers, employers, relevant government agencies, and academic institutes.

• 한국산업보건학회지
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• 제26권1호
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• pp.58-63
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• 2016

Objectives: One major limitation encountered in retrospective exposure assessment for epidemiological study is the lack of exposure records and information maintained by companies which if they existed would allow the estimation of past exposure to hazardous operations and agents. This study developed a job-specific questionnaire(JSQ) to estimate exposure profiles among semiconductor workers, including operation and job. Methods: This JSQ can be directly applied to workers who work or have worked in a wafer fabrication or a chip packaging and assembly facility. Results and Conclusions: We used this JSQ to obtain past exposure information from semiconductor workers via face-to-face investigation. Major contents include questions on the facilities, operations and jobs to which they have been exposed since they entered employment in the semiconductor industry. The total number of questions in the JSQ is 18. Responses to this JSQ can be used not only to estimate retrospective exposure to operations and jobs in the semiconductor industry, but also to associate with the risk of all causes of death and risk of disease, including cancer.

• 한국산업보건학회지
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• 제25권2호
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• pp.146-155
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• 2015

Objectives: The aims of this study were to set up benzene exposure matrices according to industry and process and to assess the risk of those occupational exposure to benzene. Methods: The benzene exposure matrices were assembled depending on industry and process, based on an exposure database provided by KOSHA(the Korean Occupational Safety and Health Agency), which was gathered from a workplace hazards evaluation program in Korea. These exposure matrices were assessed by Hallmark Risk Assessment tool. Results: The benzene was treated 412 industries sector(36%), 2,747 business places, and 471 industrial processes according to database. The arithmetic mean of past decade 8 hours time-weighted average of airborne benzene concentrations in the workplace was 0.10722 ppm. 1.07% of the total sample were greater than OEL, and 59.8% were showed less than the limit of detection. The highest risk values(Danger Value) were seen 36 industries including manufacture of general paints and similar product and 12 processes, such as other painting of manufacture of metal fabricated members. Exposure matrices based on employee exposure data base may provide exposure histories and can be used in epidemiological studies. Conclusions: It was found that more attentions should be paid to 36 among 412 industries and 12 of 471 processes, with a higher risk value.

• Molecular & Cellular Toxicology
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• 제4권4호
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• pp.360-365
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• 2008

In the last several years, studies on the association of oxidative stress damage with exposure in the work place have been conducted. Xenobiotics create an imbalance of the homeostasis between oxidant molecules and antioxidant defense. By monitoring oxidative stress biomarkers, information was obtained on damages induced by oxidative stress and the toxicity of xenobiotics. In the present study, a Job Exposure Matrix (JEM) was constructed using the data from the Working Environment Measurement (WEM) of painters in the shipyard industry from the past 3 years to assess the exposure status. Additionally, by measuring the concentration of urinary malondialdehyde (MDA), the effect of lipid peroxidation was examined. The subjects consisted of 68 workers who were exposed to mixed organic solvents in the painting process and 25 non-exposure controls. The exposure indices of the exposure groups were significantly different (sprayer: 0.83, touchup: 0.54, assistant: 0.13, P<0.05). The urinary MDA concentration of the exposure group was 48.60${\pm}$ 39.23 ${\mu}mol$/mol creatinine, which was significantly higher than 18.03${\pm}$16.33 ${\mu}mol$/mol creatinine of the control group (P<0.05). From the multiple regression analysis of urinary MDA, the regression coefficient for exposure grade was statistically significant. In future studies, evaluation of the antioxidant levels of subjects should be performed simultaneously with quantitative exposure measurements.

• 한방안이비인후피부과학회지
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• 제17권3호
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• pp.95-101
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• 2004

Objective: The purpose of this study is to investigate the past history of the patients with peripheral type nerve palalysis. Methods: We examined the age, sex, region, month, season, past disease and cause of 692(343 male, 349 female) patients with peripheral type nerve palalysis who visited Dept. of Acupuncture and Moxibustion, Bundang Oriental Medicine Hospital, Dongguk University, from 2001-10-1 to 2004-9-30. Results: 420 patiens(60.7$\%$) were in the age between 30-59. The region, sex, and seasonal distribution didn't have a remarkable contrasts. In the past disease, Hypertension(14.5$\%$), Diabets mellitus(9.2$\%$), Gastric diseases(3.9$\%$) and Live diseases(3.8$\%$) were investigated highly than other diseases. In the distribution of cause, fatigue(36.3$\%$), unknown(34.8$\%$), stress(19.2$\%$) cold exposure(12.1$\%$) were investigated highly than other causes.