• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.30 no.3
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• pp.270-279
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• 2020

Objective: The aim of this study was to propose revision of the occupational exposure limit(OEL) for 1-Bromopropane(1-BP) following a review of the appropriateness of the standard in light of increasing epidemiological data and handling risk. Materials and Methods: The results of toxicity and epidemiologic investigations for 1-BP and agencies' OELs were compared and reviewed through a literature review. In order to investigate the status of 1-BP handling in South Korea, data from work environment actual condition survey results and work environment measurement results were used. Results: The toxicity of 1-BP, such as central nervous system(CNS) damage, peripheral neuropathy, hematological adverse effects, and developmental and reproductive toxicity(male and female) has been reported. ACGIH recommends 0.1 ppm as a TLV-TWA value, but the OEL of South Korea stands at 25 ppm, which is 250 times higher than the TLV-TWA. Although 1-BP is a specially managed substance under the Industrial Safety and Health Law, the currently applied OEL cannot be said to be a safe level based on the results of epidemiological studies to date. In a work environment measurement in 2017, the total number of samples was 626, which were derived from 78 industries, and the average concentration was 1.173 ppm(standard deviation 2.88). Conclusions: To protect the health of workers handling 1-BP, estimated to be 780 in South Korea, it is necessary to strengthen the OEL(TWA) to a level of 0.3 ppm(lower than the 0.34 ppm with known toxic effects), which is believed to be safe as a result of epidemiological investigation. "Skin" notation should be recommended.

• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.482-488
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• 2005

Objectives : We conducted an investigation on 14 cases of brucellosis in Gyeongsangbuk-do during 2003-2004 to understand the source of infection and the transmission routes of brucellosis. Methods : The authors visited the each of the health centers and we examined the patients, their written epidemiologic questionnaire and the occurrence of bovine brucellosis. We visited the patients' living and work areas, and we examined their occupations, the date they developed symptoms, the progress of their symptoms, whether or not they were treated, their current status, whether or not they consumed raw milk and raw meat, and if their work was related to cattle breeding and the related details. We reviewed the results of the blood tests and medical records and we examined the cattle's barn. Results : There were 3 patients in 2003 and 11 patients in 2004. All of their brucella antibody titer exceeded 1:160. The patients' symptoms were fever, myalgia, malaise, chills and an influenza-like illness, but the clinical signs were absent on the medical records. Brucella abortus were cultured from 3 of the patients' blood samples. Conclusions : When the authors discovered the transmission routes, they were divided into 4 different sorts. The first route was related to cattle birth such that patients touched the calves or placentas that were infected with the Brucella species. The second route was related to performing artificial insemination on the cattle and the semen that was used for artificial insemination. The third route was due to the ingestion of raw meat and milk. The last route was due to sexual intercourse between the patients.

• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.457-464
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• 2005

Objectives : An outbreak of salmonellosis occurred among the student s and staff of D primary school in Yeongcheon-si, 2004. This investigation was carried out to prevent any recurrence of this outbreak and to study the infection source and transmission of the salmonellosis. Methods : The authors conducted a questionnaire survey among 1,205 students and staff members from D primary school about the ingestion of the school lunch and drinking water, and the manifestation of their symptoms. The author examined rectal swabs, the tap water and microorganism cultures, and we also investigated the dining facility and water supply facility. Results : The diarrheal cases were defined as the confirmed cases or the persons who had diarrhea more than one time with symptoms such as fever, vomiting and tenesmus. The diarrheal attack rate was 28.0%. Ingestion of fried bean curd with egg had a significantly high association with the diarrheal attack rate (p<0.05), and the relative risk of the fried bean curd with egg was 10.68 (95% CI=3.88-29.41), as was determined by logistic regression analysis. The bacterial counts in the tap water of the food preparation room and toilet (first floor) exceeded the maximum permissible counts. S. Enteritidis bacteria were only cultured from the fried bean curd with egg of all the supplied foods on September 3, 2004. Conclusions : The major cause of salmonellosis was presumed to be the contaminated bean curd via contaminated tap water due to a water leak of a school water pipe. This contaminated bean curd was under prepared, which allowed the S. Enteritidis to survive and multiply prior to its ingestion.

• Journal of Preventive Medicine and Public Health
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• v.33 no.1
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• pp.10-16
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• 2000

Objectives : This study was carried out to investigate the sources of infection and modes of transmission of an outbreak of shigellosis that occurred among students of B middle and high school in Bonghwa, Korea from May 1 to 21, 1999. Methods : We conducted questionnaires to 468 students, 38 stalls and 9 food handlers twice times (May 6, May 21) for follow up and secondary attack rate. Personal details and history of illness and exposure to particular foods were sought. And we conducted rectal swab for culture to 243 students, 33 staffs and 9 food handlers. Bacteriological examinations of water in the school were done. Cases were identified as subjects who had diarrhea (two or more loose stools in a 24-hour periods) on or after May 1. Results : A total of 307 cases (attack rate: 59.6%) of 515 subject were identified, including 50 confirmed (46 students and 4 staffs) by S. sonnei. All 9 food handlers denied illness and were had rectal swab for culture at May 6 that were negative for S. sonnei. 146 of 307 reported fever, 156 had tenesmus, 44 reported vomiting, and only 5 of 307 reported blood in the stool. The median duration of diarrhea was 4 days (range: 1-18 days). The mean incubation period until onset of diarrhea was 63 hours (range: 46-144 hours) and the secondary attack rate was 2.8% (43 cases of 1,561 family members). Risk for illness was higher among students who had eaten watered kimchi at March 30 than among those who did not [301(72.7%) of 417 versus 5(9.6%) of 52; RR=7.51;95% CI=3.26-17.31]. Conclusion : The source of infection was estimated to be contaminated watered kimchi by ore or two food hardier who is presumed to be carrier.

• Journal of Preventive Medicine and Public Health
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• v.35 no.1
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• pp.33-40
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• 2002

Objective : From an analysis of a community outbreak of measles in Youngju, Gyeongbuk, in March 2000, the authors evaluated the effectiveness of the measles vaccination and its determinants to Provide an epidemiologic basis for the establishment of a vaccination policy. Methods : Information was collected regarding the vaccinations from the health records of four primary schools and through a questionnaire surrey of the parents of students in two middle and two high schools (N=4638). Measles cases were surveyed from the patient list of each school and from case reports in the public health center. The attack rate and vaccine effectiveness of measles was evaluated by school; grade; frequency, region, and institution of vaccination. Results : The attack rate cf measles, 6.3% among the total subjects, was higher in middle school students (15.8%) than in primary (2.0%, p<0.05) and high school students (8.9%, p<0.05). The attack rate of the unvaccinated group was 4.6-fold higher than the vaccinated group in primary schools (p<0.05). Vaccine effectiveness was 83.2% among lower graders of primary schools, 34.0% among higher graders of primary schools,26.1% in middle schools, and -7.0% in high schools. In multiple logistic regression analysis, grade in school (odds ratio, 0.77; 95% CI=0.67-0.87) and frequency of vaccination (odds ratio, 0.57: 95% CI=0.37-0.58) were significant predictors of the outcome. Conclusions : We concluded that the explosive outbreak of measles in this area resulted from both inadequate vaccination coverage and secondary failure of vaccination. There was no evidence of any effect of the cold chain system on the vaccine failure.

• Journal of Preventive Medicine and Public Health
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• v.37 no.4
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• pp.345-352
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• 2004

Objectives : Previous studies showed that death certification by physicians was an important predictor to improve the quality of death certificate data in South Korea. This study was conducted to examine the proportion of death certificates issued by physicians and associated factors in South Korea from 1990 to 2002. Methods : Data from 3,110,883 death certificates issued between 1990 and 2002, available to the public from the National Statistical Office of Korea, were used to calculate the proportion of death certificates issued by physicians and to examine associated factors with logistic regression analysis. Results : The overall proportion of death certificates issued by physicians increased from 44.6% in 1990 to 77.6% in 2002 (mean: 63.5%). However, the proportion was greatly influenced by the deceased's age. In 2002, more than 90% of the deceased aged 51 or less were certified by physicians. A higher proportion was found among deceased who had tertiary education (college or higher) living in more developed urban areas. Conclusion : The information regarding the cause of death for younger, well-educated deceased in urban areas of South Korea may show a higher level of accuracy. Epidemiologic research using information on causes of death may well benefit from the continually increasing proportion of death certificates issued by physicians in the future in South Korea.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.2
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• pp.236-243
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• 2015

Objectives: This study sought to examine the association between long working hours and depressive symptoms among interns and residents in South Korea. Methods: We analyzed a cross-sectional survey of 1,661 interns and residents from the 2014 Korean Interns & Residents Survey. Total working hours during the preceding week was assessed and classified into five categories(i.e. less than 60 hours, 60-79 hours, 80-99 hours, 100-119 hours, and 120-168 hours). Depressive symptoms during the previous week were measured by using ten items from the Center for Epidemiologic Studies Depression Scale questionnaire. Multivariate negative binomial regression was applied to examine the association between long working hours and depressive symptoms after adjusting for potential confounders, including medical specialty and training year. All analyses were performed using STATA/SE version 13.0. Results: 86%(N=1,429) of interns and residents worked 60 hours or more per week. Compared to the "less than 60 hours" group, long working hours for interns and residents were significantly associated with depressive symptoms: "60-79 hours"(PR: 1.56, 95% CI: 1.05, 2.32), "80-99 hours"(PR: 2.27, 95% CI: 1.54, 3.33), "100-119 hours"(PR: 2.62, 95% CI: 1.76, 3.89), and "120-168 hours"(PR: 3.28, 95% CI: 2.21, 4.86). Conclusions: This study found that long working hours were prevalent among interns and residents in South Korea, and it was associated with depressive symptoms.

• Safety and Health at Work
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• v.9 no.2
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• pp.125-132
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• 2018

Background: According to the US Bureau of Labor Statistics, musculoskeletal disorders (MSDs) accounted for 32% of all nonfatal injury and illness cases in 2014 among full-time workers. Our objective was to review and summarize the evidence linking occupational exposures to vibration and awkward posture with MSDs of the shoulder and neck. Methods: A literature search was conducted using the terms musculoskeletal disorders, vibration, and awkward posture. All types of observational epidemiologic studies, with the exception of case reports, published during 1998-2015 were included. Databases searched were MEDLINE (Ovid), Embase (Ovid), Scopus, Ergonomic Abstracts, NIOSHTIC-2, and Health and Safety Science Abstracts. Results: Occupational exposures to whole-body or hand-arm vibration were significantly associated with or resulted in MSDs of the shoulder and neck. Awkward postures while working were also associated with MSDs in these locations. These findings were consistent across study designs, populations, and countries. Conclusion: Occupational exposure to vibration and awkward posture are associated with shoulder and neck MSDs. Longitudinal studies are required to elucidate the mechanisms responsible for these associations, and intervention studies are warranted.

• Safety and Health at Work
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• v.11 no.2
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• pp.165-172
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• 2020

Background: To gain a better understanding of nonfatal injuries in Alaska, underutilized data sources such as workers' compensation claims must be analyzed. The purpose of the current study was to utilize workers' compensation claims data to estimate the risk of nonfatal, work-related injuries among occupations in Alaska, characterize injury patterns, and prioritize future research. Methods: A dataset with information on all submitted claims during 2014-2015 was provided for analysis. Claims were manually reviewed and coded. For inclusion in this study, claims had to represent incidents that resulted in a nonfatal acute traumatic injury, occurred in Alaska during 2014-2015, and were approved for compensation. Results: Construction workers had the highest number of injuries (2,220), but a rate lower than the overall rate (34 per 1,000 construction workers, compared to 40 per 1,000 workers overall). Fire fighters had the highest rate of injuries on the job, with 162 injuries per 1,000 workers, followed by law enforcement officers with 121 injuries per 1,000 workers. The most common types of injuries across all occupations were sprains/strains/tears, contusions, and lacerations. Conclusion: The successful use of Alaska workers' compensation data demonstrates that the information provided in the claims dataset is meaningful for epidemiologic research. The predominance of sprains, strains, and tears among all occupations in Alaska indicates that ergonomic interventions to prevent overexertion are needed. These findings will be used to promote and guide future injury prevention research and interventions.

• Annals of Clinical Neurophysiology
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• v.9 no.1
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• pp.5-10
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• 2007

Background: Bell's palsy (BP) is a self-limited rapid onset facial palsy that is non-life-threatening and has a generally favorable prognosis. Facial paralysis can be caused by numerous conditions, all of which should be excluded before the diagnosis of BP is reached. The etiopathogenesis and clinical course of BP are uncertain. So we analyzed the epidemiology and clinical course of BP patients. Methods: The subjects include 100 cases of BP examined during the period of 18 months. Careful clinical history, neurologic examinations, laboratory tests, electrophysiologic studies, and brain imaging were performed. Follow-up examinations were done once a week during the first month and subsequently once a month until normal function was restored or for up to 3 months. Facial nerve function was assessed by House-Brackman (HB) facial nerve grading scale and electrophysiologic studies. Results: Except 13 recurrent BP patients, we analyzed 87 BP patients. Forty-four (50.6%) were men and 43(49.4%) were women and the mean age was 51.0(${\pm}16.6$) years. Three (3.4%) patients showed a familial tendency. The initial examination within 1 week after attack revealed 35.2% was below HB grade 4 and 64.8% was above grade 3. The associated symptoms are as follows; postauricular pain, increase tear flow, taste change, hyperacusis and drooling. The initial facial nerve conduction study and blink reflex within 1 week after attack showed abnormal findings in 12.6% and 100%, respectively. Brain MRI was performed in 59(67.8%) patients and showed abnormal enhancement of affected nerve in 57(96.6%). Follow-up examination showed that 78.2% of the patients partially improved within 4 weeks and completely improved within 3 months. Finally 80.5% of the total patients obtained normal function in 3 months. Conclusions: We report epidemiologic, clinical, electrophysiologic and radiologic characteristics of BP patients.