BACKGROUND: Hot tub lung is a hypersensitivity pneumonitis caused by nontuberculous mycobacteria (NTM); the primary causative agent is Mycobacterium avium complex (MAC) post contaminated water exposure. Recently, 2 cases of hot tub lung were found in public bath bodyscrubbers working in Korea. However, the disease causing NTM was not identified in these cases. Here, we reported one case, along with clinical diagnostic approach to occupational medicine throughout worksite investigation. CASE: A 53 year-old woman working in the public bath for 13 months' duration developed shortness of breath. She had been cleaning the locker room, several pools and floors every day, and using scrubbers with detergent and warm water. After examination, the patient was diagnosed with hypersensitivity pneumonitis based on high resolution computerized tomography and lung biopsy. Because the Mycobacterium avium was identified in both the patient's sputum and the warm pool, she was diagnosed with hot tub lung due to MAC. CONCLUSION: Hot tub lung due to MAC was confirmed in public bath housekeeper. However, few cases have been reported, even though there are many cases. To prevent damages caused by hot tub lung, general environmental management such as ventilation and cleaning is important for bath operators. Likewise, awareness needs to be increased in workers with potential NTM environmental exposure and in clinicians through education about hot tub lung in order to reduce adverse harm from misdiagnosis and mistreatment of tuberculosis.
Alveolitis, Extrinsic Allergic ; Baths ; Biopsy ; Detergents ; Diagnostic Errors ; Dyspnea ; Environmental Exposure ; Female ; Floors and Floorcoverings ; Humans ; Korea ; Lung ; Mycobacterium ; Mycobacterium avium ; Mycobacterium avium Complex ; Nontuberculous Mycobacteria ; Occupational Medicine ; Sputum ; Tuberculosis ; Ventilation ; Workplace

OBJECTIVE: The objective of this study was to evaluate the degree of intelligible speech in workers wearing hearing protective devices and the differences in background noise type. METHODS: A total 82 shipyard company employees and normal hearing volunteers were recruited as subjects from a company in Ulsan: subjects were classified to the hearing-impaired group or to the control group according to hearing status. They were tested pure tone and speech audiometry in varying test environments including signal-to-noise ratio and background noise type in a headphone and in a free field environment. RESULTS: For both groups, the attenuation of hearing protective devices was greater at high frequencies. For the hearing-impaired group, speech discrimination scores differences between the unprotected and the protected ear were not significant between background noise type, when speech was presented at 65 dBA. However speech intelligibility in white noise background was lower than in the other background noise types when speech was presented at 75 dBA. CONCLUSIONS: Workers' speech intelligibility increased with an increasing signal-to-noise ratio. Speech intelligibility was also dependent on background noise type. Workers and their colleagues were trained to pronounce words more loudly and more clearly when they wearing hearing protective devices or other communication methods that do not use sound signal should be considered.
Audiometry, Speech ; Ear ; Ear Protective Devices ; Hearing ; Humans ; Noise ; Signal-To-Noise Ratio ; Speech Intelligibility ; Speech Perception

OBJECTIVE: The Korean Marine Corps enlistees endure tremendous physical and mental stress during basic military training, resulting in an increased risk of musculoskeletal injuries. The aim of this study was to investigate the incidence and type of the musculoskeletal injury problems and the risk factors associated with injuries among the Marine Corps recruits and to suggest preventive measures. METHODS: The study subjects were the Marine Corps recruits (n=8,231) who were enlisted from July, 2008 to March, 2009 for basic military training. We used a prospective cohort design and collected basic demographic information and subject musculoskeletal injury risk factors through a questionnaire on the first day basic training. The subjects were followed for the subsequent 6-week military training period. RESULTS: The cumulative incidence of musculoskeletal injuries was 13.4% during the 6-week training period, and more than half of the injuries involved the lower limbs at or below the level of the knee. Based on multivariate logistic regression analysis, the following factors were related to an elevated risk for injuries: age, height, educational level, subjective health perception, injury history during the past year, and stress scale after entrance. CONCLUSION: Based on our study results, the application of injury prevention measures such as stress management program and gradual fitness increasing program to the Marine Corps recruit training would contribute to the reduction of musculoskeletal injuries.
Cohort Studies ; Humans ; Incidence ; Knee ; Logistic Models ; Lower Extremity ; Military Personnel ; Musculoskeletal System ; Prospective Studies ; Questionnaires ; Risk Factors

OBJECTIVE: This study investigated case clusters of pneumoconiosis among residents near cement factories in Young_Wol, Korea. METHODS: There were 1,396 residents of a total 3,418 residents surveyed for this study. Informations on demographics, health-related behaviors (smoking and drinking), past medical history, and clinical symptoms were collected using a self-administered questionnaire. All study participants underwent a physical examination, including chest X-ray, and physicians' interview. Chest CT (computerized tomography) was taken if there was abnormal finding on chest X-ray and physicians' interview. RESULTS: We detected 5 cases of pneumoconiosis. 2 cases were related to occupational exposure to dust, such as underground mining and the breaking up of concrete. However, 3 cases were not related to occupational or environmental exposure, except that persons were living near cement factories and limestone mines. CONCLUSION: This study suggests that the long-term exposure of cement dust among residents near cement factories and mines may lead to the development of pneumoconiosis.
Calcium Carbonate ; Demography ; Dust ; Environmental Exposure ; Humans ; Korea ; Mining ; Occupational Exposure ; Physical Examination ; Pneumoconiosis ; Questionnaires ; Thorax

OBJECTIVE: This study was conducted to assess the reliability, the validity, the psychological characteristics, and the internal structure of the Negative Acts Questionnaire-Revised (NAQ-R) for nurses for the assessment of the workplace bullying. METHODS: A total of 190 female nurses who worked in a university hospital and who had participated in an annual health surveillance program were recruited into the study. A structured questionnaire was used to evaluate each participant's workplace bullying, job stress, and psychosocial wellbeing. Workplace bullying was assessed using the negative acts questionnaire-revised (NAQ-R), job stress was assessed using the Korean Occupational Stress Scale-Short Form (KOSS-SF) and psychosocial wellbeing was assessed using the Psychosocial Wellbeing Index-Short Form (PWI-SF). Resulting answers from the questionnaires were analyzed by chi-square, ANOVA, correlation analysis, and factor analysis. RESULTS: Victims of workplace bullying of nurses in a hospital is 37(19%) based on operational bullying criteria. The Cronbach's alpha for the negative acts questionnaire-revised (NAQ-R) is 0.9260. By exploratory factor analysis, we conclude that 3 factor are most relevant. Criterion validity was satisfied with that a negative acts questionnaire-Revised (NAQ-R) resulting in a statistically significant and positive relationship with PWI-SF , construct validity was satisfied with that NAQ-R has statistically significant and high positive correlation with the occupational climate of the KOSS results. CONCLUSIONS: The negative acts questionnaire-revised (NAQ-R) is a reliable and valid tool for the assessment of workplace bullying in the hospital nurse. By using this tool, we can imply the prevalence of and the condition of workplace bullying among the nurse.
Bullying ; Climate ; Female ; Humans ; Prevalence ; Questionnaires ; Reproducibility of Results

OBJECTIVE: This study was conducted to evaluate the reliability of a questionnaire from an epidemiological study for nuclear power plants workers in Korea. METHODS: Among a total of 8,832 nuclear power plants workers who participated in the questionnaire survey, we selected 646 workers who repeatedly submitted the self-reported questionnaire. The reliability of the questionnaire for the categorical items was measured using kappa statistics and percentages of exact agreement, false disagreement and positive disagreement. Significance was evaluated for the continuous items by paired t-tests and intra-class correlation coefficients (ICCs). RESULTS: The questionnaire was observed to be highly reliable for the smoking history (kappa=0.85), which is known as an important confounding factor in assessing the cancer risk among radiation workers. Education level as a surrogate for the socio-economic status also appeared to be highly reliable with a kappa=0.89 and 95.09% of exact agreement. The history of alcohol drinking, medical exams and diseases showed more than moderately good agreement between the first and second responses (kappa>0.4). The self-reported values for physical measurements, the smoking period and smoking amount, and the period of alcohol drinking were highly correlated between the two responses (ICC>0.7). CONCLUSIONS: The questionnaire from an epidemiological study for nuclear power plants workers in Korea was found to be reliable for most items. To estimate the cancer or noncancer risk for nuclear power plants workers, we need to use the national database for incidence of diseases or death from diseases and the exposure history, and the medical records as well as the data collected from this study.
Alcohol Drinking ; Epidemiologic Studies ; Incidence ; Korea ; Medical Records ; Nuclear Power Plants ; Questionnaires ; Smoke ; Smoking

OBJECTIVE: We studied two districts in Korea in order to investigate if the frequency of fish consumption has an effect on the blood mercury levels. METHODS: This survey was conducted on 164 fishing district residents in Geoje city and 219 agricultural district residents in Changwon city from July to August in 2008. The data on the demographic characteristics, the living environment, lifestyle habits and the frequency of fish consumption was collected by interviewers. We used ANOVA to estimate the particular relevance between the frequency of fish consumption and the blood mercury concentration, and other various factors. RESULTS: The mean total blood mercury level was 6.54+/-4.01 microgram/L for the total study population. Our results were even higher than that of the National Health and Nutrition Examination Survey (USA) in, 2001~2002 and the German Environmental Survey in, 1998. In this study, there was a significant difference for the frequency of eating fish between the groups. (p<0.01, The level of the groups that ate fish 3 to 4 times per week was significantly higher as compared with the level of the other groups that ate fish 2 to 3 times per month and 1 to 2 times per week, respectively). As the frequency of fish consumption increased, so did the blood mercury concentration. CONCLUSIONS: We found that the blood mercury concentration increases along with fish consumption and this was statistically significant and this fact reveals that fish consumption is positively related to the blood levels of mercury. Accordingly, we need systematic and periodic research on the general population to prevent mercury poisoning, which can be caused by low-level mercury exposure from dietary intake such as chronic fish consumption.
Eating ; Korea ; Life Style ; Mercury Poisoning ; Nutrition Surveys

OBJECTIVE: The prevalence and mortality rate of cardiovascular disease (CVD) have increased among Koreans over the past 20 years. To manage and control this disease, various CVD risk assessment tools such as KOSHA (Korean Occupational Safety and Health Agent) CVD risk assessment, the presence of metabolic syndrome and the Framingham risk score (FRS) have been developed and applied to employees at the workplace. This study was designed to compare the validity of the CVD risk assessment tools mentioned above with the findings of coronary CT angiography (CCTA). METHODS: The subjects of this study who were 490 male-workers aged between 31 and 70, and these subjects were selected among those who had visited a University Hospital for a general health examination and who underwent CCTA from January 2007 to June 2009. Chi-square tests and logistic regression analysis were used to compare and analyze the associations between the CVD risk assessment tools and the coronary artery changes such as calcification and stenosis. RESULTS: Metabolic syndrome (OR=1.90, 95% CI 1.23-2.95) and the Framingham risk score (OR=2.71, 95% CI 1.83-4.01) were the significant and meaningful predictors of coronary artery calcification. On the analysis of the association with coronary artery stenosis, only the Framingham risk score (OR=2.21, 95% CI 1.46-3.36) turned out to be a significant and meaningful predictor. CONCLUSION: The results suggest that the Framingham risk score is a relatively valid CVD risk assessment tool. Henceforth, to effectively manage cardiovascular diseases in the workplace, advanced tools and indicators for management should be considered and provided based on meaningful study results.
Aged ; Angiography ; Cardiovascular Diseases ; Constriction, Pathologic ; Coronary Stenosis ; Coronary Vessels ; Humans ; Logistic Models ; Occupational Health ; Prevalence ; Risk Assessment

OBJECTIVE: Recent researches suggest that trans,trans-muconic acid (t,t-MA) would be an adequate metabolic biomarker for low-level benzene exposure. Few study have investigated the association between the t,t-MA and platelet count, and this is the primary aim of this study. METHODS: From May 2004 to June 2004, 326 chemical factory workers took part in a questionnaire survey and they underwent urinary t,t-MA and CBC assessment. The questionnaire covered general aspects of health and the occupational and smoking histories. Statistical analyses of outcomes were performed using SPSS 14.0 for Windows. RESULTS: The subjects' urinary t,t-MA concentration (geometric mean and geometric standard deviation) was 0.28 mg/g creatinine (2.62). No significant differences between different occupations among the chemical workers were found. The urinary t,t-MA concentrations in the smokers and non-smokers were 0.32 mg/g creatinine (2.44) and 0.25 mg/g creatinine (2.77) respectively, and the difference was statistically significant (p<0.05). There was no significant difference in the platelet count based on occupation and the smoking history. There was significant correlation between log(platelet) and log(t,t-MA)(r=-0.116 p=0.039). The regression equation log(platelet) = -0.002xAge + [-0.029xlog(t,t-MA)] + 2.436, R2=0.032, was calculated from linear regression analysis with log(platelet) as the dependent variable. Cross-tabulation between 2 subgroups that were divided by the 90-percentile level of the t,t-MA (0.819 mg/g creatinine), and 2 subgroups that were divided by the 10-percentile level of the platelet count (175,000) was conducted. Higher distribution in subgroup with platelet count below 175,000 was demonstrated in the subgroup with a urinary t,t-MA above the 90-percentile, with an odds ratio of 3.01. CONCLUSIONS: The study may be limited by not taking into account factors such as smoking quantity and sorbic acid, which may confound urinary the t,t-MA concentration as well as medication and infection that may affect the platelet count. Yet it is meaningful that the correlation between the urinary t,t-MA concentration and the platelet count was found through linear regression analysis and the chi-square test, and further, this outcome may be used as a basis for a study to establish the acceptable limit of urinary t,t-MA in Korea.
Benzene ; Blood Platelets ; Creatinine ; Korea ; Linear Models ; Occupations ; Odds Ratio ; Platelet Count ; Questionnaires ; Smoke ; Smoking ; Sorbic Acid

OBJECTIVE: We investigated the differences among the patients who were diagnosed with carpal tunnel syndrome according to the frequency of exposure to wrist-burdening work by using carpal tunnel syndrome surveillance system. METHODS: The study subjects were a total of 855 patients from 1,017 patients who were diagnosed with carpal tunnel syndrome in 9 university hospitals from May, 2001 to October, 2004, and we excluded 161 patients who had no clear information for their occupational status. The subjects were classified into three groups according to four types of wrist-burdening work: 1) repetitive use of wrists, 2) inappropriate posture of the hand, 3) use of vibrating tools, and 4) overpressure work on the hand or palm, - as defined in the operational definition by the National Institute for Occupational Safety and Health (NIOSH). The subjects with two or more types of wrist-burdening work were classified as 'high risk group', the subjects with one type of wrist-burdening work were classified as 'intermediate risk group', and the subjects with none of the types of wrist-burdening work were classified as 'low risk group'. We used chi-square test, Fisher's exact test and ANOVA for comparing the characteristics according to the 3 subgroup. RESULTS: The mean age in the high risk group was the lowest(53 years), and there was a significant difference among the groups for the mean age(p<0.05). The high risk group included the most males with 39(22.0%). The subjects in the high risk group had significantly more jobs in agriculture.forestry.fisheries, factory work, and simple labor and less comorbidities, including diabetes and rheumatoid arthritis(p<0.05). The subjects in the intermediate risk group had a higher proportion of service workers. There were significant differences for the symptoms of carpal tunnel syndrome according to the frequency of exposure to wrist-burdening work. The subjects in the high risk group showed the highest proportion of work-related aggravation of symptoms with 88(76.5%) and the highest mean number of days absent from work(6 days) as related to carpal tunnel syndrome. CONCLUSION: Worker in agriculture.forestry.fisheries, factory work, and simple labor showed significantly more frequent carpal tunnel syndrome, and so management strategies are needed to prevent them from developing carpal tunnel syndrome.
Carpal Tunnel Syndrome ; Comorbidity ; Employment ; Hand ; Hospitals, University ; Humans ; Male ; National Institute for Occupational Safety and Health (U.S.) ; Occupations ; Posture ; Wrist