A purpose of present study is to provide basic information evaluating the utility of Magnetic Resonance imaging as a biological marker estimating manganese effects to central nervous system among welders, which is conducted by comparing urinary and blood manganese concentrations and signal intensities of brain MR images between exposed group and non-exposed group, evaluating the objectivity of subjective grading estimated by correlations between Pallidal signal intensity index (P. I) and subjective grades among exposed group, and comparing the difference of signal intensities according to presence of neurologic symptoms, signs and exposure variables among the exposed group. The exposed group is composed of 11 welders complaining severe symptoms or showing neurological signs, and the non-exposed group is composed of 5 patients who admitted a hospital. Urinary manganese concentrations and signal intensities in T1-weighted MR images among exposed group were higher than those of the non-exposed group significantly, which exhibits that increased signal intensities in T1-weighted MR image represent the effect of manganese exposure. P. Is among the exposed group revealed relatively high correlations with subjective grades ( gamma =0.63, p=0.037) , which suggests the objectivity of subjective grade. Signal intensity in globus pallidus was a suitable single variable representing the effect of manganese accumulation in C.N.S system appropriately, which was verified as follows ; Increased signal intensities among the exposed group had the highest frequency and intensity in the globus pallidus, and the P.I. had a relatively high correlation coefficient ( gamma 0.62, p=0.044) with total score of subjective grades. Signal intensity with subjective grading in globus pallidus represented very high correlation gamma =0.97, p=0.00) with total score of subjective grades, and had a similar correlation coefficient with many variables. It is hard to argue that signal intensities are markers representing pathologic change in C.N.S system or can be used as a diagnostic tool for manganese intoxication, because signal intensities had no difference between the exposed group and the non-exposed group according to presence of neurological signs.
Biological Markers ; Brain ; Central Nervous System ; Globus Pallidus ; Humans ; Magnetic Resonance Imaging* ; Male* ; Manganese ; Neurologic Manifestations

Occupational diseases may be defined only medically or scientifically, and even then, their definition is not simple. However, compensable occupational diseases involve the additional layer of legal systems and social welfare policies as well. Their multifaceted nature makes determining the work-relatedness of these diseases more complex. Korea has established standards for the recognition of occupational diseases in Schedule 5 of the Enforcement Decree of the Labor Standards Act, and specific criteria for the recognition of occupational diseases are listed in Schedule 3 of the Enforcement Decree of the Industrial Accident Compensation Insurance Act. The new list of compensable occupational diseases comprises 13 articles as an open-ended system. The newly added articles pertain to lymphohematopoietic (Article 5) and infectious diseases (Article 9), as well as diseases of other target organs. Furthermore, the article on liver diseases (Article 8) has been partially revised. The new act has been changed to clarify the meaning as it has been presented in recent research. It is necessary to achieve agreement among concerned parties, including experts from the legal, medical, and social domains to resolve the issues of work-relatedness, causation, notion of aggravation, and so on for preparing a list and a process that are more reasonable.
Adult ; Benzene/toxicity ; Communicable Diseases/*economics ; Dimethylformamide/toxicity ; Drug-Induced Liver Injury/economics ; Female ; Hematologic Diseases/chemically induced/*economics ; Humans ; Lead/toxicity ; Liver Diseases/*economics ; Male ; Middle Aged ; Occupational Diseases/*economics ; Republic of Korea ; Trichloroethylene/toxicity ; Vinyl Chloride/toxicity ; Workers' Compensation/*economics

Standards for the recognition of occupational diseases (ODs) in Korea were established in 1954 and have been amended several times. In 2013, there was a significant change in these standards. On the basis of scientific evidence and causality, the International Labour Organization list, European Commission schedule, and compensated cases in Korea were reviewed to revise the previous standards for the recognition of ODs in Korea. A disease-based approach using the International Classification of Diseases (10th version) was added on the previous standards, which were agent-specific approaches. The amended compensable occupational neurological disorders and occupational mental disorders (OMDs) in Korea are acute and chronic central nervous system (CNS) disorders, toxic neuropathy, peripheral neuropathy, manganese-related disorders, and post-traumatic stress disorder. Several agents including trichloroethylene (TCE), benzene, vinyl chloride, organotin, methyl bromide, and carbon monoxide (CO) were newly included as acute CNS disorders. TCE, lead, and mercury were newly included as chronic CNS disorders. Mercury, TCE, methyl n-butyl ketone, acrylamide, and arsenic were newly included in peripheral neuropathy. Post-traumatic stress disorders were newly included as the first OMD. This amendment makes the standard more comprehensive and practical. However, this amendment does not perfectly reflect the recent scientific progress and social concerns. Ongoing effort, research, and expert consensus are needed to improve the standard.
Female ; Humans ; Mental Disorders/chemically induced/*economics/pathology ; Nervous System Diseases/chemically induced/*economics/pathology ; Occupational Diseases/*economics ; Occupational Exposure ; Republic of Korea ; Stress Disorders, Post-Traumatic/diagnosis/*economics ; Workers' Compensation/*economics

OBJECTIVES: In order to evaluate the degree of manganese exposure and its health hazards effect on welders in manufacturing industry. METHODS: The author measured airborne, blood and urine concentrations of manganese and blood chemistry, and also observed clinical symptoms and signs on 60 welders for case an.d 60 non-welders for control working in manufacturing industry by age maching method. RESULTS: The geometric means of blood and urine concentrations of manganese were 1.13 +/- 1.38 microgram /dI and 2.52 +/- 1.37 microgram /I for Welders group, 1.09 +/- 1.68 microgram /dl and 1.86 +/- 1.34 microgram / I for Non-welders group. Airborne concentration of manganese was 0. 15 +/- 1.66 mg/m3 for exposured group, and the urinary mean concentration of manganese was statistically significant difference between exposured and non-welders group (P < 0.05). Clinical signs in welders group were palmomentle reflex (23.3%), tremor (20.0%) and grabellar sign (5.0%). Symptoms in welders group were fatigue (66.7%), amnesia (66.7%), excessive sweating (51.7%), nervousness (51.7%), general weakness (48. 3%) and arthralgia (46.7%) and so on, and there was statistically significant difference compared to non-welders group (P<0.05). Manganese exposure effects on blood chemistry were not observed. There were statistically significant correlation between manganese concent- ration in blood and urine (r=0. 269), airborne and urine (r=0. 601) and airborne and blood (r=0. 268). CONCLUSION: The author suggest that further studies are followed to evaluate the health status of welders whose blood and urine manganese concentrations were below normal reference level, and to establish the questionnaire and the diagnostic tools for early detecting the chronic manganese poisioning on welders.
Amnesia ; Anxiety ; Arthralgia ; Chemistry ; Fatigue ; Manganese* ; Questionnaires ; Reflex ; Sweat ; Sweating ; Tremor

The asbestos textile industry is characterized by the highest asbestos ambient air concentration of those workers who have suffered from high incidence of lung cancer, malignant mesothelioma, and other asbestos related diseases (ARDs). Also, asbestos dust occurred in a factory can be disseminated into the environmental air around the factory, which can cause ARDs among residents of the factory. High lung cancer and malignant mesothelioma mortality rates among asbestos textile workers were established, and increase of ARDs among residents around the factory has been reported. A large number of environmentally exposed residents as well as severity of health problems among asbestos textile workers would cause huge social problems. The high exposure group needs to be monitored for early detection and management. In addition, a nationwide mandatory malignant mesothelioma registration system to identify exposure sources and high risk groups might help to predict and manage ARDs.
Asbestos ; Dust ; Environmental Exposure ; Incidence ; Lung Neoplasms ; Mesothelioma ; Social Problems ; Textile Industry ; Textiles

OBJECTIVE: To show the prevalence of the dorsomedial cutaneous nerve (DMCN) injury in the hallux valgus and to evaluate whether the sensory nerve damage contributes to pain and sensory impairment in the great toe. METHOD: Sixty feet of healthy adults (normal group) and 26 feet of patients with hallux valgus (hallux valgus group) were evaluated with sensory nerve conduction study of DMCN. The prevalence of the nerve injury was compared between the two groups. Sensory nerve action potentials of DMCN in hallux valgus feet were analyzed and compared according to the patient's symptom and the severity of the radiographic measurements of the feet. RESULTS: The prevalence of DMCN injury was 42.3% of the hallux valgus group. The peak latency of the DMCN sensory action potential of the symptomatic feet showed statistically significant delay compared to the asymptomatic group (p<0.05). Delay of the peak latency and decrement of the amplitude of the DMCN were statistically significant among the three groups as the valgus deformity worsened (p<0.05). CONCLUSION: DMCN injury should be considered in addition to soft tissue injury or arthritis in the differential diagnosis of the pain, burning sensation or numbness associated with hallux valgus.
Action Potentials ; Adult ; Arthritis ; Burns ; Congenital Abnormalities ; Diagnosis, Differential ; Foot ; Hallux Valgus* ; Hallux* ; Humans ; Hypesthesia ; Neural Conduction* ; Prevalence ; Sensation ; Soft Tissue Injuries ; Toes

BACKGROUND: We report cases of high lead exposure in a Korean steel manufacturing company and a likely cause for these cases. CASE REPORT: Neurological examinations, neurobehavioral tests, blood tests, and urine tests were performed to detect an association between high lead exposure and physical symptoms for workers in a steel manufacturing company. In order to determine the cause of high lead exposure, the work process and environment was assessed. The highest lead exposure was during the work process. We found that the interior of an oil storage tank was coated with lead-containing paint, leading to severe exposure during the cutting process. In two observations, 4 of 12 workers diagnosed with occupational disease were found to have high exposure to lead from the storage tank and three had increased beta-2 microglobulin levels in the blood (indicative of urinary tract damage). CONCLUSIONS: Lead management, including routine measurements of the working environment and examinations of lead concentrations in workers, are needed in the korean scrap metal industry. In addition, rules requiring workers to wear personal protective equipment and receive education about lead exposure should be strictly enforced.
Hematologic Tests ; Humans ; Neurologic Examination ; Occupational Diseases ; Paint ; Steel ; Urinary Tract

OBJECTIVES: Absenteeism due to musculo-skeletal disorders (MSDs) of workers is an important index of occupational health. Since research on its causes is rare in Korea, the risk factors for absenteeism due to MSDs should be studied. METHODS: Using the 2nd Korean working condition survey data, we investigated the prevalence of absenteeism due to MSDs. We also analyzed the risk factors for absenteeism by multiple logistic regression analysis in Korean employees. RESULTS: Prevalence of absenteeism due to MSDs was 0.7% in all employees, 0.5% in men, and 0.9% in women. In logistic regression analysis, gender, age, presence of a representative worker organization, working on tight deadlines, and pace of work dependent on automated equipment/machine were risk factors of absenteeism due to MSDs for both sexes. For males, working time, working at a very high speed were additional risk factors. For females, pace of work dependent on numerical production, performance, and targets were additional risk factors. Although not included in the multiple logistic regression analysis, handling heavy loads in both sexes and average monthly income for women were risk factors in the univariate analysis. CONCLUSIONS: For absenteeism due to MSDs, the presence of a representative worker organization, along with work pace and its determinants were important risk factors.
Absenteeism ; Female ; Handling (Psychology) ; Humans ; Korea ; Logistic Models ; Male ; Occupational Health ; Prevalence ; Risk Factors

OBJECTIVES: This study aimed to reveal the multiple factors that are related to the work-related musculoskeletal disorders (WMSDs) of shipbuilding workers, and to elucidate the relationship between musculoskeletal symptoms and factors such as the change of working conditions, job stress and physical workload. METHODS: The study sample comprised 1,059 shipbuilding workers. A structured-questionnaire was used to assess the general characteristics, job stress, psychosocial well-being index (PWI), physical workload, change of working conditions and information concerning musculoskeletal symptoms. We estimated the relations of job stress, physical workload and intensity of labour to musculoskeletal symptoms using univariate and multiple logistic regression analyses. RESULTS: The symptom prevalence of musculoskeletal disorders in any part of the body was 89.5% by 'criteria 1'in the order of back (58.6%) and shoulder (56.3%). After adjustment for sociodemographic factors, posture factor (Odds ratio [OR]=1.06, 95% confidence interval [ C I ] = 1 . 0 0~1.12), non-posture factor (OR=1.17, CI=1.05~1.31), Borg scale (OR=1.15, C I = 1 . 0 0~1.32), relative work intensity increase (OR=1.92, CI=1.08~3.41), labor flexibility increase (OR=2.04, CI=1.04~4.01), high job demand (OR=2.68, CI=1.48~4.88), and high risk stress group (OR=13.50, CI=3.15~57.97) were all found to be significantly associated with musculoskeletal disorders. CONCLUSION: These results suggest that WMSDs have multiple risk factors such as stress, physical workload and change of working conditions. High job demand, increased relative intensification of work and increased flexibility, especially such as subcontract, outsourcing and importing of contingent work, were very important factors associated with increasing WMSDs.
Logistic Models ; Outsourced Services ; Pliability ; Posture ; Prevalence ; Risk Factors ; Shoulder

Diffuse mesotheliomas of the pleura and peritoneum are considered "signal tumors" of asbestos exposure. Although asbestos use in Korea started before the national liberation, it rose abruptly with economic development in 1970's. Considering latent period of mesotheliomas as twenty years, occupational mesothelioma cases would increase rapidly. In Korea construction is a major industry which use asbestos. Because workers in construction industry are mostly composed of daily based workers, it is hard to calculate the number of workers involving asbestos related work, to manage them with organized method, to educate them about adverse effects of asbestos and protection methods, to check health status of them periodically, and to follow them up. Although a case of occupational mesothelioma which was found in a asbestos textile worker have been reported, no case related with construction workers have been reported so far in Korea. The authors experienced occupational malignant pleural mesothelioma combined with asbestosis in a boilermaker and plumber in a construction industry.
Asbestos ; Asbestosis* ; Construction Industry ; Economic Development ; Korea ; Mesothelioma* ; Peritoneum ; Pleura ; Textiles