Factors Affecting Dyspnea in Retired Coal Miners in Korea / 대한산업의학회지

OBJECTIVES: This study was done to examine the risk factors for the dyspnea of retired coal miners in Korea. METHODS: Eight hundred and sixteen male workers who took the health examination for retired coal miners in the T hospital were recruited, in this study and their health examination records were employed to assess the risk factors for dyspnea. Both univariate and multiple logistic regression analyses were used to estimate the relationship between known risk factors and the presence of dyspnea. RESULTS: Variables in the univariate analysis, which showed a significant relationship with dyspnea were age(>or=60 years) (OR : 2.20, 95% CI : 1.63-3.00), work duration(>or=2 0 years) (OR : 1.67, 95% CI : 1.24-2.25), profusion of small opacity(>or=1/0) (OR : 1.81. 95% CI : 1.30-2.51), large opacity(>or=A) (OR : 2.19, 95% CI : 1.30-3.70), and the ratio of the distance between the start of the first division of the right and left main pulmonary arteries divided by the transverse diameter of the thorax (cor pulmonale index)(>or=0 . 3 6 ) (OR : 2.37, 95% CI : 1.77-3.17). The multivariate analysis using logistic regression analysis showed age(>or=60 years)(OR : 1.69, 95% CI : 1.28-2.21), smoking amount(>or=1 filters/day) (OR : 1.61, 95% CI : 1.06-2.45), no experience of having quit smoking (OR : 1.40 95% CI : 1.06-1.84), and the cor pulmonale index(>or=0.36)(OR : 1.75, 95% CI : 1.34-2.29) were associated with an increased risk for dyspnea. CONCLUSIONS: These results suggests that the cor pulmonale index is the most significant risk factor in predicting dyspnea in retired coal miners. In addition, this study also revealed that workers aged 60 years or more or smokers were more likely to experience dyspnea as compared to those aged 60 years or less and nonsmokers.

The Incidence Rate of the Pneumoconiosis among Retired Coal Miners / 대한산업의학회지

OBJECTIVES: The incidence rate of pneumoconiosis among retired coal miners was studied at Taebackchungang hospital. METHODS: Newly developed pneumoconiosis0=1/0) cases were gathered from films of ex-coal miners who were diagnosed as normal at the previous examination after retirement. RESULTS: 228 exminers were confirmed as normal at the previous examination after retirement. 37 ex-miners were diagnosed as pneumoconiosis (equal or greater than 1/0) at the next examination. CONCLUSIONS: The incidence rate was 29.5/1000 person-year. The incidence was calculated by the examined year. In 1995, 1996, 1997, the incidence rates were 104. 8, 37. 1, 14.1 per 1000 person-year respectively. There was no development of pneumoconiosis among retired coal miners who retired more than 20 years ago or who worked less than 10 years.

Radiological discrimination of cor pulmonale with pulmonary function and electrocardiography finding in coal workers pneumoconiosis / 대한산업의학회지

The radiological finding, pulmonary ventilatory function test data, electrocardiography data were used for the study of relationship between these variables in cor pulmonale and normal group in coal Workers pneumoconiosis. The hospital records of 674 men who were diagnosed as coal workers pneumoconiosis were analysed. The ratio between interhilar distance and thoracic transverse diameter was used as a criterion in grouping of cor pulmonale. If. the ratio is greater than 0.36, it was classified, to cor pulmonale. The squared canonical correlation of pulmonary function variable to cor pulmonale grouping was less than 0.15. Logistic regression analysis with pulmonary function variable and electrocardiographic variable showed sensitivity 50.5%, specificity 72.2%, correctness 62.2%. Vital capacity and Forced vital capacity showed significantly decreased value in cor pulmonale group after adjustment of covariates( age, degree of dyspnea, pack-years of smoking, perfusion of small and large opacity).

Follow up Lower Back Pain Management Method in Lower Back Pain Complaining Workers of Kyungin Area / 대한산업의학회지

Nine hundred and twelve workers who complained low back pain(LBP) were interviewed. After one year, 483 workers were followed showed improvement of LBP symptom. In the case of job change, it showed improvement rate of 91.2%. In case of exercise theraphy, 82.8% of workers showed improved symptom. Medical care(Clinical medication, physical theraphy and folk medicine) group showed 63.2% of improvement rate. In the presence of sciatic pain on the time of first interview, the improvement rate of LBP was lower than the absent group.

Radiological Findings of Low Back Pain Complainers in Some Part of Kyungin area workers / 대한산업의학회지

Preliminary survey of low back pain(LBP) was conducted from 7,668 workers of some part of Kyungin area. Among them, 1,183 workers complained LBP. If we do not mind X-ray findings, the prevalence rate of LBP was 15.4%. Lumbar series(anterior-posterior view, lateral view, both oblique view) were take from 973 workers who complained LBP. Three radiological findings which are not related with congenital anomaly or definite trauma-degenerative spondylitis, flattening of the lumbar spine, decreased intervertebral disc space were selected. In the group of degenerative spondylitis, the prevalence rate was relatively high after thirties in both sex. In female, prevalence rate was more higher in 5th and 6th decades than other decades. In the case of flattening of lumbar spine, the prevalence rate was relatively high in 2nd, 3rd and 4th decades in both sex. In case of decreased intervertebral disc space, there was no specific prevalent age group in both sex.

Chronic fatigue syndrome in workers of Bucheon, Kimpo and Bupyung area / 대한산업의학회지

No abstract available.

Toxic encephalopathy in a worker exposed to organic solvents; a case report / 대한산업의학회지

No abstract available.

ECG Sign of Cor Pulmonale in Coal Workers' Pneumoconiosis Died from Cardio-respiratory faiture / 대한산업의학회지

Electrocardiographic sign was studied for the evaluation of the state of Corpulmonale in coal workers' pneumoconiosis who were admitted and dead as complication of CWP in Don-ghae hospital, Fourty-eight cases were gatherpd. The prevalence rate of right axis deviation was 28.3%. p-pulmonale in lead II was 30.4%, R/S< or =1 in V5 was 23.9. But che pulmonary artereal pressure can be increased without the change of ECG. so the elortrocardiugraphical sign should be treated as reference data.

The Relationship between the Cause of Death and Life Expectancy by FEV in Coal Workers Pneumoconiosis / 예방의학회지

Sixty-two medical records of patients with coal workers' pneumoconiosis who died in hospital as coal workers' pneumoconiosis were analyzed for study of the relationship between forced expiratory volume in one second(FEV1) and life expectancy in coal workers' pneumoconiosis. In the group who died of asphyxia from hemoptysis, life expectancy were well fitted with FEV1 (p<0.05). But others were not well fitted to simple linear regression equation. The prevalence of ECG sign of cor pulmonale was more in the group of cardiorespiratory failure than asphyxia group. So, in the case of far advanced cor pulmonale, it was difficult to predict life expectancy by simple linear regression equation.

Gas diffusion effect on Nifedipine in coal workers pneumoconiosis by radio-opacity size / 예방의학회지

Carbon monoxide diffusing capacity(DLco) was evaluated before and after nifedipine administration in coal workers' pneumoconiosis by the size of radioopacity. Nifedipine was administered to 18 men and 17 men of small round opacity group and large opacity group respectively. Placebo was administered to 19 men and 15 men of small and large opacity group respectively. In large opacity group DLco was increased after nifedipine administration. But, it was not significant statistically(0.05 < p < 0.01). In other groups, there were no significance difference between and after medication.

Change of FVC, FEV1 after Discontinuance of Bronchodilator in Coal Workers' Pneumoconiosis Patients / 예방의학회지

For the evaluation of change of FVC and FEV1 after discontinuance of bronchodilator in the coal workers' pneumoconiosis patients, 17 pairs of patients were selected. They were matched by the age(+/-5 y.o.) and the type of ventilatory impairment. Pulmonary function was measured 2 times bimonthly before and after the drug discontinuance discontinued after measurement of PFT for 2 times. In case group the bronchodilator was discontinued after measurement of PFT for 2 times. In control group there was no interruption of medication. FVC, FEV1 decreased in both group as measurement progress. Simple linear regression coefficients against the month of measurement were calculated in both group and tested for parallelism between two groups. The results of test revealed that both regression coefficients were parallel. So in conclusively, discontinuance of medication of bronchodilator for coal workers pneumoconiosis patients has no effect on the decreasing rate of FVC, FEV1.

Forced Expiratory Volume in One Second and ECG Sign of Cor Pulmonale in Coal Workers' Pneumoconiosis / 예방의학회지

The medical record of ECG and pulmonary function test of 297 cases who were dead at hospital or admitted as coal workers' pneumonociosis were used for the study of the relationship between forced expiratory volume in one second(FEV1.0) and ECG sign of pulmonale. The incidence of T wave inversion in V1 lead was significantly increased as FEV1.0 decrease. The incidence of T wave inversion in V1 lead was over the half in the group of FEV1.0 less than 0.7 liter.

Quantitative Analysis of Quartz, Mica, and Feldspar in Respirable Coalmine Dust in Taebaek Area by Fourier Transform Infrared Spectrophotometry / 예방의학회지

A Fourier transform infrared spectrophotometric method was described for the determination of quartz, mica(sericite) and feldspar(potassium feldspar) in respirable dust in Taebaek area. The results were as follows; 1) The concentration of minerals were determined from the intensity of absorption peak of quartz at 799 cm-1, sericite at 539 cm-1, and potassium feldspar at 648 cm-1 respectively. 2) The precision(C. V. %) for the quartz determination was 7.70+/-2.68 % from 10 to 200 microgram of quartz. 3) The precision for the sericite determination was 16.34+/-6.82 % from 30 to 500 microgram of serictite. 4) The precision for the potassium feldspar determination was 5.28+/-1.74 % from 30 to 500 microgram of potassium feldspar. 5) The concentration of respirable dust in Taebaek area was 4.90+/-3.29 mg/m3(0.4-93.7%), percent quartz was 1.80+/-4.14% (0.01-20.56%), percent sericite was 11.37+/-6.43% (0.00-29.69%), percent potassium feldspar was 8.15 % (n=7, 3.41-19.70%). 6) The difference of respirable coal dust, quartz, and sericite concentration in drilling, coal cutting, hauling and separating was significant respectively (p<0.05).

A Study on Occupational History of Coal Workers' Pneumoconiosis / 예방의학회지

The purpose of this study is to analyze occupational history of coal miners with pnemoconiosis. In this study, occupational chracteristics of 49 coal miners with pneumoconiosis were compared with those of 45 coal miners without pneumoconiosis but in similar age category (43-52 years of age) based on interview survey. Various indices on occupational characteristics were developed for the following areas: duration of employment, perception of working condition, working density, dust concentration, temperature, humidity, and experience of respirator wearings. Perception of working condition were measured in 5 points scales but experiences of respirator wearing was measured in 3 points scale. Each index was multiplied by duration of employment. From the analysis, only the experience of respirator wearing showed statistically significant difference between the two groups. Therefore, respirator wearing seemed to be effective in reducing occurrence of pneumoconiosis.

Serum Immunoglobulin Levels in Coal Workers' Pneumoconiosis / 예방의학회지

Serum Immunoglobulin (Ig)A, IgG, IgM, levels were measured in 99 coal workers' pneumoconiosis (CWP) patients and 12 healthy coal workers and 9 non-miners to compare with each group by the radiological categories, its complications and working period in coal mine. Serum were measured by nephelometry. The findings were as follows: 1) Serum IgA levels were significantly different between three groups of CWP patient, healthy coal worker and non-miner (mean+/-standard deviation: 226.4+/-87.7, 221.3+/-45.1, 170.1+/-65.7 respectively). 2) There were no significant differences of Ig levels among radiological categories of CWP. 3) There were no significant differences of Ig levels among simple pneumoconiosis and its complicated disorders. 4) The three Ig levels were slightly increased in the group of mining years less than 20 years (IgA: r=0.1869, p<0.10 IgG: r=0.2902, p<0.05 IgM: r=0.2889, p<0.05).

Quartz Concentration and Respirable Dust of Coal Mines in Taeback and Kangneung Areas / 예방의학회지

In order to investigate working conditions of underground coal mines, this work was undertaken to evaluate the respirable dust and the concentration of quartz in Taeback and Kangneung areas. The concentration of quartz was determined by Fourier Transform Infrared Spectrophotometry. The results were as follows; 1) The concentration of respirable dust of drilling and coal face in Taeback and Kangneung areas were as followed. 2) Distribution of respirable dust was well fitted to the long-normal distribution and geometric mean value was log(-1) 0.37+/-log(-1) 0.47 (2.34+/-2.95) mg/m3. 3) The difference of respirable dust concentrations in Taeback and Kangneung areas was not significant statistically (p>0.05). 4) The concentration of quartz of drilling and coal face in Taeback and Kangneung areas were as followed. 5) Distribution of quartz concentrations was well fitted to the log-normal distribution and geometric mean value was log(-1) 0.33+/-log(-1) 0.45 (2.14+/-2.82)%. 6) The difference of quartz concentrations in Taeback and Kangneung areas was not significant (p>0.05), but significant at drilling sites and coal faces (p<0.05).

Changes of Forced Vital Capacity and Forced Expiratory Volume in one second of hospitalized Pneumoconiosis Patients / 예방의학회지

Forced vital capacities (FVC's) and forced expiratory volumes in one second (FEV1.0's) of 26 pneumoconiosis patients were checked at admission and were followed up for 10 months through hospitalization. FVC's and FEV1.0's were slightly improved in 10 months after admission. The improvement of FVC's was statistically significant. In the group of large opacities in chest radiographs, FVC's and FEV1.0's were lower than those values in small opacity group at admission but improved more progressively. Similar finding was noted in the group of emphysema; those values were lower at admission but improved more progressively than those of non-emphysema group.

Study on Subjective Symptoms that was Complained by Organic Solvent Handling Workers / 예방의학회지

The subjective symptom and other responded relations for 69 male workers handling organic solvent in xxx a pharmacy as exposure group and 87 male workers in noise workshop were studied and analyzed. It was concluded as follows. 1. The age of both exposure group and control group with the subjective symptom indicated a negative correlation. 2. Drinking and smoking of the exposure group complained of the subjective symptom shown the negative correlation and the control group also shown the positive correlation. 3. The occupational experience of the exposure group complained of the subjective symptom indicated the negative correlation and the control group also indicated the positive correlation.

Study on Applicability of Predictive Equations of Subjective Symptoms of Workers Using Organic Solvents in Certain Factory / 예방의학회지

For the study of the applicability of predictive equation of subjective symptoms of workers using organic solvents, 67 male workers using organic solvents were selected. The predictive equation was quotated from previous Cheon's study. All the datas of necessary variables were gained. The predictive values and observed values were compared. The results were summarized as below; 1. The difference between predictive values and observed values were characteristically large. The coefficient of determination between the two values was 0.0024. 2. The R2 value of multiple stepwise regression equation derived from present study was 0.2827.

Dental Erosion in two Factories using Acids / 예방의학회지

Acid erosion of teeth was studied in two factories. The A was the textile factory possessing dyeing process using acids. The B was the metal product manufactof,ing factory possessing electroplating process. The control group was selected at the same factory not exposed to acids. The results were summarized as below. 1. The pH of saliva was the range of 6.6+/-6.8 in both factories. 2. The prevalence rate of erosion of teeth was higher in case group at ,the B. It was statistically significant. 3. The rate of erosion of incisor were the range of 12%16% (case group), 7%21,0,o (control group) at the A and 10%-20%(case group), 2%-5%(control group) at the B. 4. The rate of erosion of degree 3 which is necessary for conforming, owing to occupational induction, were 8.9% (incisor: A) and 6.8/0,o(incisor: B).