• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.51.1-51.15
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• 2023

Background: Recently, there has been increasing worldwide concern about outdoor air pollution, especially particulate matter (PM), which has been extensively researched for its harmful effects on the respiratory system. However, sufficient research on its effects on cardiovascular diseases, such as hypertension, remains lacking. In this study, we examine the associations between PM levels and hypertension and hypothesize that higher PM concentrations are associated with elevated blood pressure. Methods: A total of 133,935 adults aged ≥ 40 years who participated in the Korean Genome and Epidemiology Study were analyzed. Multiple linear regression analyses were conducted to investigate the short- (1-14 days), medium- (1 and 3 months), and long-term (1 and 2 years) impacts of PM on blood pressure. Logistic regression analyses were conducted to evaluate the medium- and long-term effects of PM on blood pressure elevation after adjusting for sex, age, body mass index, health-related lifestyle behaviors, and geographic areas. Results: Using multiple linear regression analyses, both crude and adjusted models generated positive estimates, indicating an association with increased blood pressure, with all results being statistically significant, with the exception of PM levels over the long-term period (1 and 2 years) in non-hypertensive participants. In the logistic regression analyses on non-hypertensive participants, moderate PM₁₀ (particulate matter with diameters < 10 ㎛) and PM_2.5 (particulate matter with diameters < 2.5 ㎛) levels over the long-term period and all high PM₁₀ and PM_2.5 levels were statistically significant after adjusting for various covariates. Notably, high PM_2.5 levels of the 1 year exhibited the highest odds ratio of 1.23 (95% confidence interval: 1.19-1.28) after adjustment. Conclusions: These findings suggest that both short- and long-term exposure to PM is associated with blood pressure elevation.

• 대한인간공학회지
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• 제28권1호
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• pp.29-36
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• 2009

A Study was conducted to investigate the type and level of occupational risk factors for the onset of work-related musculoskeletal disorders (WMSDs) in non-manufacturing industries. Total of 38 worksites were investigated from 5 different business areas such as financial institution, transportation service, building maintenance, sanitary service and educational service. Major job and task category were classified and corresponding occupational risk factors such as awkward posture, force exertion, repetitiveness of job, and work/rest cycle were examined using various ergonomic risk analysis techniques. Sets of matrices were developed including types and levels of risk factors for the classified jobs and tasks from 5 different non-manufacturing industries. Also possible ergonomic remedies were suggested for the improvement working conditions. Results and risk factor matrices can be applied as a guideline for the investigation of WMSDs risk factors in similar industries for the prevention of WMSDs.

• 한국산업보건학회지
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• 제24권4호
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• pp.547-555
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• 2014

Objective: This study was conducted to investigate the association between subjective distress symptoms and argon welding among workers in Gyeongnam Province shipyard. Method: 31 argon and 29 non-argon welding workers were selected as study subjects in order to measure concentrations of personal dust, welding fumes and other hazardous materials such as ZnO, Pb, Cr, FeO, MnO, Cu, Ni, $TiO_2$, MgO, NO, $NO_2$, $O_3$, $O_2$, $CO_2$, CO and Ar. An interviewer-administered questionnaire survey was also performed on the same subjects. The items queried were as follows: age, height, weight, working duration, welding time, welding rod amounts used, drinking, smoking, and rate of subjective distress symptoms including headache and other symptoms such as fever, vomiting and nausea, metal fume fever, dizziness, tingling sensations, difficulty in breathing, memory loss, sleep disorders, emotional disturbance, hearing loss, hand tremors, visual impairment, neural abnormality, allergic reaction, runny nose and stuffiness, rhinitis, and suffocation. Statistical analysis was performed using SPSS software, version 18. Data are expressed as the mean ${\pm}SD$. An ${\chi}^2$-test and a normality test using a Shapiro wilk test were performed for the above variables. Logistic regression analysis was also conducted to identify the factors that affect the total score for subjective distress symptoms. Result: An association was shown between welding type (argon or non-argon welding) and the total score for subjective distress symptoms. Among the rate of complaining of subjective distress symptoms, vomiting and nausea, difficulty breathing, and allergic reactions were all significantly higher in the argon welding group. Only the concentration of dust and welding fumes was shown to be distributed normally after natural log transformation. According to logistic regression analysis, the correlations of working duration and welding type (argon or non-argon) between the total score of subjective distress symptoms were found to be statistically significant (p=0.041, p=0.049, respectively). Conclusion: Our results suggest that argon welding could cause subjective distress symptoms in shipyard workers.

• Korean Chemical Engineering Research
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• 제62권1호
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• pp.27-35
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• 2024

메탄, 프로판 등을 주성분으로 하는 연료가스는 폭발위험장소에서 사용될 수 있으며, 누출로 인한 공정조건의 영향으로 불균일한 혼합기를 형성할 수 있다. 균일한 혼합기를 대상으로 측정된 문헌 데이터를 이용한 화재 폭발 위험성 평가, 손상 예측은 가스 누출에 의한 실제 폭발 사고와 다른 결과를 얻을 수 있다. 본 연구에서는 가스 누출시 나타날 수 있는 농도 변화에 있어서 불균일성 혼합기의 폭발압력, 화염속도 등의 폭발특성을 조사하였다. 길이 0.82 m의 스테인리스 재질의 밀폐 배관에서 수행하였으며 컬러 초고속 카메라 및 압력 센서를 사용하여 관찰하였다. 또한 배관 내의 시간에 따른 농도차이 변화에 대해 회귀분석 모델을 사용하여 불균일 혼합물의 정량화 방법을 제안하였다. 본 연구의 농도 불균일성 조건에 있어서 메탄 폭발 시 전파화염은 불균일성 농도가 높아짐에 따라 화염 면적의 증가가 관찰되었고 이는 난류 화염의 주름진 화염 구조와 유사하였다. 메탄의 최대압력까지 걸리는 소요시간은 불균일성이 클수록 감소하였고, 폭발압력은 불균일성이 클수록 증가하였다. 농도가 불균일한 메탄의 K_G(폭연지수)의 범위는 1.30~1.58 [MPa·m/s]으로서 메탄의 농도가 균일성에서 불균일성로 변화하면서 17.7% 증가하였다.

• 한국환경보건학회지
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• 제37권5호
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• pp.358-368
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• 2011

Objectives: In order to evaluate the association between occupational exposure to chloroethylene (TCE) and risk of non-Hodgkin lymphoma (NHL), we conducted a meta-analysis of retrospective cohort studies and casecontrol studies and attempted to summarize the evidence of the association from molecular-epidemiological studies and experiments with human cells. Methods: In the meta-analysis, we restricted the analysis to those studies with data for chlorinated solvents, degreasers, or TCE. Studies involving dry cleaners or launderers were excluded from the analysis because use of TCE as a dry cleaning fluid has been rare since the 1960s. The data were combined using a random-effects model to estimate the summary risks (OR and RR) and 95% confidence intervals (CIs). Molecular evidence of the effect of TCE on human immune system were also reviewed and summarized. Results: Occupational exposure to TCE was strongly associated with NHL among cohort studies (number of studies=13, summary RR=1.33, 95% CI=1.04-1.70) whereas the association was not statistically significant among case-control studies (number of studies=15, summary OR=1.10, 0.98-1.23). When exposure level was considered, it became statistically significant for the highest exposure level (number of studies=5, summary OR=1.70, 1.25-2.32). Molecular evidences showed that TCE exposure in human or cultured human cells may cause a significant decrease immune cell subsets and changes in hormone levels related to immune response. Conclusions: Our results from meta-analysis and additional molecular evidence suggest that occupational exposure to TCE may cause NHL. However, unmeasured potential confounding and unclear dose-response relationships warrant further study on the role of TCE exposure in NHL carcinogenesis.

• Toxicological Research
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• 제26권4호
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• pp.329-337
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• 2010

Inhaled inorganic dusts, such as coal, can cause inflammation and fibrosis in the lungs, known as pneumoconiosis. Diagnosis of pneumoconiosis depends on morphological changes by radiological findings and functional change by pulmonary function test (PFT). Unfortunately, current diagnostic findings are limited only to lung fibrosis, which is usually irreversibly progressive. Therefore, it is important that research on potential and prospective biomarkers for pneumoconiosis should be conducted prior to initiation of irreversible radiological or functional changes in the lungs. Analytical techniques using exhaled breath condensate (EBC) or exhaled gas are non-invasive methods for detection of various respiratory diseases. The objective of this study is to investigate the relationship between inflammatory biomarkers, such as EBC pH or fractional exhaled nitric oxide ($FE_{NO}$), and pneumoconiosis among 120 retired coal miners (41 controls and 79 pneumoconiosis patients). Levels of EBC pH and FENO did not show a statistically significant difference between the pneumoconiosis patient group and pneumoconiosis patients with small opacity classified by International Labor Organization (ILO) classification. The mean concentration of $FE_{NO}$ in the low percentage $FEV_1$ (< 80%) was lower than that in the high percentage (80% $\leq$) (p = 0.023). The mean concentration of $FE_{NO}$ in current smokers was lower than that in non smokers (never or past smokers) (p = 0.027). Although there was no statistical significance, the levels of $FE_{NO}$ in smokers tended to decrease, compared with non smokers, regardless of pneumoconiosis. In conclusion, there was no significant relationship between the level of EBC pH or $FE_{NO}$ and radiological findings or PFT. The effects between exhaled biomarkers and pneumoconiosis progression, such as decreasing PFT and exacerbation of radiological findings, should be monitored.

• Archives of Plastic Surgery
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• 제46권1호
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• pp.63-68
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• 2019

Background Hand injuries caused by chain saws, electric saws, and hand grinders range from simple lacerations to tendon injuries, fractures, and even amputations. This study aimed to understand the distribution of various types of hand and upper extremity injuries caused by power tools, in order to help prevent them, by investigating the incidence and cause of power tool injuries treated over a 4-year period at a single institution in Korea. Methods We reviewed the medical records of patients who visited a single institution for power tool-induced injuries from 2011 to 2014. The distribution of sex, age, injured body part, type of injury, and mechanism of injury sustained by patients who received hand and upper extremity injuries from using an engine saw, electric saw, or hand grinder was evaluated. Results Among 594 subjects who were injured by power tools, 261 cases were hand and upper extremity injuries. The average age was 53.2 years. Tendon injury was the most common type of injury. An electric saw was the most common type of power tool used. More injuries occurred in non-occupational settings than in occupational settings. Conclusions In this study, power tool-induced hand and upper extremity injuries were mostly caused by direct contact with electric saw blades. More injuries occurred due to non-occupational use of these tools, but the ratios of amputations and structural injuries were similar in the non-occupational and occupational groups.

• 한국산업보건학회지
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• 제17권2호
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• pp.144-152
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• 2007

Diesel vehicles are a significant source of fine carbon particle emissions including polynuclear aromatic hydrocarbons (PAHs). Urinary 1-hydroxypyrene (1-OHP) is firmly established as a useful biomarker of PAHs uptake in human. To investigate the exposure effect of PAHs in miners according to using diesel truck which was for transportation of ore, we measured urinary 1-OHP as the PAHs exposure biomarker, and analyzed the relationship between urinary 1-OHP concentration and using diesel truck. The study was performed on 118 workers (56 miners in factories using diesel truck, 62 miners in factories non-using diesel truck) and 21 controls. Urine samples were obtained at the end of shift on the survey day. There was no significance in comparison with the mean concentrations on urinary 1-OHP by age, BMI, work duration, smoking, drinking and ventilation type. But significant difference were found among urinary 1-OHP concentrations on factories according to using diesel truck (p=0.000). The urinary 1-OHP mean concentration on underground miners using diesel truck ($0.54{\mu}mol/mol$ creatinine) was higher than those of surface miners using diesel truck ($0.33{\mu}mol/mol$ creatinine, p=0.028), underground miners non-using diesel truck ($0.32{\mu}mol/mol$ creatinine, p=0.001) and controls ($0.22{\mu}mol/mol$ creatinine, p=0.000). In comparison with using status diesel truck, the urinary 1-OHP mean concentration of underground miners using diesel trucks was higher than those of other mine status. The study results would be beneficial to future environmental and biological studies of PAHs exposure to diesel exhaust in mines.

• Safety and Health at Work
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• 제12권3호
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• pp.396-402
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• 2021

Background: Styrene is one of the aromatic compounds used in acetonitrile-butadiene-styrene (ABS) producing petrochemicals, which has an impact on health of workers. Therefore, this study aimed to investigate the health risks of styrene emitted from the petrochemical industry in Iran. Methods: Air samples were collected based on NIOSH 1501 method. The samples were analyzed by the Varian-cp3800 gas chromatograph. Finally, risk levels of styrene's health effects on employees were assessed by the quantitative method of the U.S. Environmental Protection Agency (U.S. EPA) and the semiquantitative way by the Singapore Occupational Safety and Health Association. Results: Based on the results, the employees had the highest average exposure to styrene vapors (4.06 × 10^-1mg.(kg - day)^-1) in the polybutadiene latex (PBL) unit. Therefore, the most top predictors of cancer and non-cancer risk were 2.3×10^-4 and 7.26 × 10^-1, respectively. Given that the lowest average exposure (1.5 × 10^-2mg.(kg - day)^-1) was in the dryer unit, the prediction showed a moderate risk of cancer (0.8 × 10^-6) and non-cancer (2.3 × 10^-3) for the employees. The EPA method also predicted that there would be a definite cancer risk in 16% and a probable risk in 76% of exposures. However, according to the semiquantitative approach, the rate of risk was at the "low" level for all staff. The results showed that there was a significant difference (p < 0.05) between the units in exposure and health risk of styrene (p < 0.05). Conclusion: Given the high risk of styrene's health effects, appropriate control measures are required to reduce the exposure level.

• 한국엔터테인먼트산업학회논문지
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• 제15권4호
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• pp.299-307
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• 2021

본 연구는 작업치료(학)과 대학생들이 인지하는 융합교육에 대한 인식 및 경험, 필요성과 요구를 확인하고자 하는 조사연구이다. 그리하여 작업치료(학)과 교육과정 내 융합 교과목 및 비정규 프로그램 개발시 기초자료로 제공하고자 한다. 2020년 12월 03일부터 한 달 간 4개 영역, 14개 문항으로 구성된 웹 설문지를 배포하였고, 최종적으로 130명의 자료를 분석하였다. 연구결과는 다음과 같다. 첫째, 작업치료(학)과 재학생들의 융합교육에 대한 인식과 경험은 낮은 편이다. 둘째, 57.7%의 응답자가 작업치료학 전공에서 융합교육이 필요하다고 인식하고 있었으며, 융합교육을 통해 '작업치료 직무관련 지식 향상'을 기대했다. 셋째, 학문분야로는 '자연 과학', 교과목으로는 '보조기의지학 및 보조공학, 일상생활활동', 작업치료사의 직무로는 '일상생활 동작훈련'에 융합교육 요구가 높은 것으로 확인되었다. 본 연구결과는 향후 작업치료(학)과 교육과정 개발 및 융합교육을 위한 비정규 프로그램 개발 시 기초 자료로 활용할 수 있다. 앞으로 작업치료학 교육과정에서도 4차 산업혁명을 대비한 융합교육과 프로그램 개발에 대한 요구가 증가될 것이라 생각한다. 본 연구의 자료가 대학에서 작업치료학 교육을 담당하는 교수자들에게 의미 있게 활용되기를 기대한다.