BACKGROUND: Lower-limb varicose veins (VVs) are common and known to have a higher prevalence among people who work in occupations requiring prolonged standing. In the Republic of Korea, however, VV-related occupational factors have seldom been examined. This study was conducted to assess the prevalence of VVs among nurses, an occupational group considered to be at high risk of VVs, and determine the occupational risk factors of prolonged standing. METHODS: Between March and August 2014, a questionnaire survey coupled with Doppler ultrasonography was conducted on the nurses working at a university hospital. RESULTS: A total of 414 nurses participated in the survey and diagnostic testing. From the survey analysis and test results, the prevalence of VVs in nurses was estimated to be 16.18%. Significant factors for venous reflux were age [odds ratio (OR) = 1.06, 95% confidence interval (CI) = 1.03–1.10], pregnancy (OR = 2.15, 95% CI = 1.17–3.94), and delivery (OR = 2.02, 95% CI = 1.08–3.78). The statistical significance of these factors was verified after risk adjustment for sociodemographic factors (OR = 3.40, 95% CI = 1.27–9.09). CONCLUSION: Factors significantly associated with venous reflux were increasing age and prolonged working hours (≥ 4 hours) in a standing position (OR = 2.80, 95% CI = 1.08–7.25), even after risk adjustment for sociodemographic factors. This study is significant in that an objective diagnosis of VVs preceded the analysis of the risk factors for VV incidence, thus verifying objectively that VVs are associated with occupations requiring prolonged hours of working in a standing position.
Diagnosis ; Diagnostic Tests, Routine ; Humans ; Incidence ; Occupational Groups ; Occupations ; Posture ; Pregnancy ; Prevalence* ; Republic of Korea ; Risk Adjustment ; Risk Factors* ; Ultrasonography, Doppler ; Varicose Veins*

BACKGROUND: Health problems in shift workers vary including obesity acting as a risk factor in cerebrovascular diseases. Recent studies have commonly determined the prevalence of obesity in shift workers on the basis of body mass index. The accuracy of BMI for diagnosing obesity are still limited apparently. Consequently, this study aimed to determine the relationship between shift work and obesity according to the total body fat percentage in Korean wage workers. METHODS: From the Fourth and the Fifth Korea National Health and Nutrition Examination Survey (2008-2011), after military personnel were excluded, a total of 2952 wage workers (20 < or = age < or = 65) whose current jobs were their longest jobs were selected as subjects of the study. The total body fat percentage was used to determine the obesity standards (> or =25.7 % in males and > or =36.0 % in females). The subjects were divided into groups by gender and work type (manual vs non-manual), and chi-squared test was used to evaluate the relationship between socio-economic, health behavior, and work-related factors, on the one hand, and obesity, on the other. In addition, multivariate logistic regression analysis was performed to examine the effects of shift work on obesity. RESULTS: When other factors were controlled for, the risk of obesity in shift work showed a statistically significant increase (odds ratio = 1.779, 95 % confidence interval = 1.050-3.015) in the male manual worker group. However, there were no significant results in the male non-manual and female worker groups. CONCLUSION: Shift work was related to a higher risk of obesity in the Korean male manual worker group.
Adipose Tissue* ; Body Mass Index ; Female ; Hand ; Health Behavior ; Humans ; Korea* ; Logistic Models ; Male ; Military Personnel ; Nutrition Surveys* ; Obesity* ; Prevalence ; Risk Factors ; Salaries and Fringe Benefits*

We reported a case of complicated silicosis that occurred in a glass manufacturing plant worker who had presumably been exposed to low-concentration free silica for almost 20 years. To the best of our knowledge this report is the first in the Republic of Korea. The physician's first impression was cancer since the enlargement of neck and supraclavicuar lymph nodes had clearly progressed and metastasis was suspected in ultrasonography. However, it turned out to be reactive hyperplasia and anthracosis. Although lung cancer was suspected and tests were performed in 2 hospitals due to repetitive cough and dyspnea, along with weight loss of approximately 10% over the course of 7 months, the patient was eventually diagnosed with complicated silicosis and pneumothorax occurred after 1 year. Herein, we report this case with a literature review.
Anthracosis ; Cough ; Dyspnea ; Glass* ; Humans ; Hyperplasia ; Lung Neoplasms ; Lymph Nodes ; Neck ; Neoplasm Metastasis ; Plants ; Pneumothorax ; Republic of Korea ; Silicon Dioxide ; Silicosis* ; Ultrasonography ; Weight Loss

BACKGROUND: We report a case of a spray painter who developed malignant fibrous histiocytoma (MFH) of the maxillary sinus following long-term exposure to chromium, nickel, and formaldehyde, implying that these agents are probable causal agents of MFH. CASE REPORT: The patient developed right-sided prosopalgia that began twenty months ago. The symptom persisted despite medical treatment. After two months, he was diagnosed with MFH through imaging studies, surgery, and pathological microscopic findings at a university hospital in Seoul. His social, medical, and family history was unremarkable. The patient had worked for about 18 years at an automobile repair shop as a spray painter. During this period, he had been exposed to various occupational agents, such as hexavalent chromium, nickel, and formaldehyde, without appropriate personal protective equipment. He painted 6 days a week and worked for about 8 hours a day. Investigation of the patient's work environment detected hexavalent chromium, chromate, nickel, and formaldehyde. CONCLUSIONS: The study revealed that the patient had been exposed to hexavalent chromium, formaldehyde, and nickel compounds through sanding and spray painting. The association between paranasal cancer and exposure to the aforementioned occupational human carcinogens has been established. We suggest, in this case, the possibility that the paint spraying acted as a causal agent for paranasal cancer.
Automobiles* ; Carcinogens ; Chromium ; Formaldehyde ; Histiocytoma, Malignant Fibrous* ; Humans ; Maxillary Sinus* ; Nickel ; Occupational Exposure ; Paint ; Paintings ; Seoul ; Silicon Dioxide

OBJECTIVES: This study investigated lung function in workers exposed to dusts, fumes and noxious gases at small foundries. METHODS: Lung function was measured in 148 male workers from 12 small foundries and 202 unexposed male workers. Pulmonary function tests performed included: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), percent of FEV1/FVC (FEV1/FVC%), maximum mid-expiratory flow (MMEF), peak expiratory flow (PEF), and forced expiratory flow at 25, 50, and 75% of expired FVC (FEF25, 50, 75). RESULTS: Mean values of all ventilatory indices except FEF25 of foundry workers were significantly lower than those of controls. Specifically, following stratification by smoking habits, all ventilatory indices except FEF25 of foundry workers were significantly lower than those of controls who smoked; however, there were no significant differences observed in any ventilatory indices between nonsmoking exposed workers and controls. The results of multiple linear regression analysis indicated work duration as a significant predictor of a decrease in FVC%. CONCLUSIONS: This research indicates that combined occupational exposure to dust, fumes, and gases in small foundries is associated with a reduction in lung function. Smoking may also contribute to respiratory abnormalities. These results suggested that foundry workers should be required to undergo periodic lung function tests and-in addition to not smoking, efficient use of personal protection equipment while at work is recommended.
Dust ; Forced Expiratory Volume ; Gases ; Humans ; Linear Models ; Lung ; Male ; Occupational Exposure ; Respiratory Function Tests ; Smoke ; Smoking ; Vital Capacity

OBJECTIVES: This study was carried out to investigate the effect on manganese on the brain of Sprague-Dawley rats, with particular focus on changes to anatomical pathology when brain MRI was recovered after manganese administration. METHODS: There were 15 rats divided into 3 groups of 5 based on dose of manganese: control group, low dose group (10 mg/kg), and high dose group (40 mg/kg). Each dosing group received an injection of normal saline and manganese via the tail vein once a week for 4 weeks. And then, the rats were observed for 12 weeks after stopping manganese administration. Next, each rat underwent a brain MRI and then each was sacrificed. After the rats were killed, the concentrations of blood manganese were measured, and pathologic examinations of the brain were performed. RESULTS: The signal intensity of basal ganglia on T1-weighted imaging of brain MRI did not differ between dosing groups. However, the ratio of neuron/glial cell in the basal ganglia was decreased in the low- and high-dose groups compared to the control group. CONCLUSIONS: This study showed that the damage of neuron in basal ganglia might be permanent after signal intensity of basal ganglia on T1-weighted imaging of brain MRI was recovered.
Animals ; Basal Ganglia ; Brain ; Brain Diseases ; Manganese ; Neurons ; Rats ; Rats, Sprague-Dawley ; Veins

OBJECTIVES: This study was carried out to investigate the effect of manganese on the brains of rats, and chronic exposure to manganese is known to induce Parkinsonism in human. METHODS: The rats were divided into three groups: the first group was a control group that was administrated normal saline, and the second group was subdivided into the low dose group (10 mg/kg) and the high dose group (40 mg/kg) according to the administered dose of manganese. The rats of each group received an injection of normal saline and manganese via a tail vein once a week for 4 weeks. The rats were sacraficed at 4 weeks after the first adminstration of manganese. Brain MR imaging was performed before the rats were killed. After the rats were killed, the concentration of blood manganese was measured, and pathologic examination of the brain was performed in all the groups. RESULTS: The concentration of blood manganese was increased proportionally to the administered dose. The signal intensity of the basal ganglia on the T1-weighted imaging of brain MRI was increased in accordance with the administered dose. The ratio of neuron/glial cells in the basal ganglia was decreased in the experiment group as compared to that of the control group. CONCLUSIONS: This study showed that the signal intensity and the damage of neurons in basal ganglia were increased according to the administered dose of manganese in rats.
Animals ; Basal Ganglia ; Brain ; Manganese ; Neurons ; Parkinsonian Disorders ; Rats ; Veins

OBJECTIVES: This study was carried out to investigate the effect of manganese on the brains of rats, and chronic exposure to manganese is known to induce Parkinsonism in human. METHODS: The rats were divided into three groups: the first group was a control group that was administrated normal saline, and the second group was subdivided into the low dose group (10 mg/kg) and the high dose group (40 mg/kg) according to the administered dose of manganese. The rats of each group received an injection of normal saline and manganese via a tail vein once a week for 4 weeks. The rats were sacraficed at 4 weeks after the first adminstration of manganese. Brain MR imaging was performed before the rats were killed. After the rats were killed, the concentration of blood manganese was measured, and pathologic examination of the brain was performed in all the groups. RESULTS: The concentration of blood manganese was increased proportionally to the administered dose. The signal intensity of the basal ganglia on the T1-weighted imaging of brain MRI was increased in accordance with the administered dose. The ratio of neuron/glial cells in the basal ganglia was decreased in the experiment group as compared to that of the control group. CONCLUSIONS: This study showed that the signal intensity and the damage of neurons in basal ganglia were increased according to the administered dose of manganese in rats.
Animals ; Basal Ganglia ; Brain ; Manganese ; Neurons ; Parkinsonian Disorders ; Rats ; Veins

OBJECTIVES: This study evaluated the prevalence of asbestos exposure-induced pleural thickening on chest radiograph in repairing shipyard workers. METHODS: A total of 2,114 incumbent and retired workers in a shipyard underwent chest radiograph, questionnaire study, interview, and physical exam from 2005 to 2007. Finally, 1,702 workers were selected and classified into two groups according to asbestos exposure: exposure and non-exposure groups. The characteristics in the exposure group were investigated. RESULTS: The prevalence of pleural thickening on chest radiograph was 5.2 % and 3.1 % in the exposure and non-exposure groups, respectively (p<0.05). In those aged 50 years or above, the prevalence was 17.6 % and 8.7 % in the exposure and non-exposure groups, respectively (p<0.05). The prevalence was 16.5 % and 30.2 % and the odds ratio was 2.34 (95% CI; 1.15-4.77) and 2.95 (95%CI; 1.08-8.07) in the workers with an exposure duration of 20-29 years and more than 30 years, respectively. The prevalence was higher when considering tuberculosis history. CONCLUSIONS: The prevalence was increased with increasing exposure duration was more than 20 years. The authors therefore suggest that this group should be followed up periodically by special program and that a longitudinal study with repairing shipyard workers as the cohort should be undertaken.
Aged ; Asbestos ; Cohort Studies ; Humans ; Odds Ratio ; Prevalence ; Questionnaires ; Thorax ; Tuberculosis

OBJECTIVES: This study evaluated the prevalence of asbestos exposure-induced pleural thickening on chest radiograph in repairing shipyard workers. METHODS: A total of 2,114 incumbent and retired workers in a shipyard underwent chest radiograph, questionnaire study, interview, and physical exam from 2005 to 2007. Finally, 1,702 workers were selected and classified into two groups according to asbestos exposure: exposure and non-exposure groups. The characteristics in the exposure group were investigated. RESULTS: The prevalence of pleural thickening on chest radiograph was 5.2 % and 3.1 % in the exposure and non-exposure groups, respectively (p<0.05). In those aged 50 years or above, the prevalence was 17.6 % and 8.7 % in the exposure and non-exposure groups, respectively (p<0.05). The prevalence was 16.5 % and 30.2 % and the odds ratio was 2.34 (95% CI; 1.15-4.77) and 2.95 (95%CI; 1.08-8.07) in the workers with an exposure duration of 20-29 years and more than 30 years, respectively. The prevalence was higher when considering tuberculosis history. CONCLUSIONS: The prevalence was increased with increasing exposure duration was more than 20 years. The authors therefore suggest that this group should be followed up periodically by special program and that a longitudinal study with repairing shipyard workers as the cohort should be undertaken.
Aged ; Asbestos ; Cohort Studies ; Humans ; Odds Ratio ; Prevalence ; Questionnaires ; Thorax ; Tuberculosis