A Study on Sickness Absence / 예방의학회지

The researcher intended to investigate the rate absenteeisms and other related statistics among the workers in a steel and iron industry with the criteria and the recommendation of the International Association on Occupational Health. With the well designed questionnaire and interview, 1,882 workers were surveyed from July the 24th to the 28th, 1978. The results were as follows ; The workers who experienced absence were 16.8% in July. The rate of frequency (spells) was as follow ; the frequency (spells) was 1.34, the duration was 2.29, the frequency (persons) was 101.06 and the lost time was 0.63, respectively. The main causes of sickness absence were general symptoms. such as fatigue (50.8%) and gastro-intestinal symptoms (13.8%). The frequency of sick was highly correlated to the frequency of drinking, the amount of smoking, the physical work-load and the amount of drinking, which was analysed by the stepwize multiple regression analysis. The multiple R due to the above mentioned four variables was 0.320 and the R square was 10.3%.

Understanding and Management of Occupational Diseases

No abstract available.

Occupational Hazards of Medical Workers : Present Situation and Countermeasure

No abstract available.

Smoking Habit of Coal Workers' Pneumoconiosis Patients: Their Relationship to the Findings of Chest Radiographs / 대한산업의학회지

No abstract available.

A Study on Antinuclear Antibody and Rheumatoid Factor in Coal Worker's Pneumoconiosis / 대한산업의학회지

Antinuclear antibody(ANA) and rheumatoid factor(RF) in the sera of 191 coal workers pneumoconiosis(CWP) patients, 65 healthy coal workers, and 52 non-mining controls were examined by the categories of CWP, age, duration of exposure, smoking and drinking habit. Indirect fluorescent antibody technique for ANA and latex agglutination method for RF were applied for detection. ANA was positive in 24.3% of CWP patients, 10.8% of healthy coal workers and 11.5% of non-mining controls. RF was positive in 36.5 % of CWP patients, 13.8 % of healthy coal workers and 9.6 % of non-mining controls.

Coal Miners' Recognition and Attitude toward Pneumoconiosis in Kangneung Area / 예방의학회지

This study was planned in order to investigate coal miners' recognition and attitude toward pneumoconiosis, and its relationship with related behavior for prevention of pneumoconiosis. Study object was coal miners in Kangneung area, sampled by multistage random proportional sampling, Sample size was 13% of total coal miners in Kangneung area. The results were divided into three parts: (1) descriptive results presented percent distribution, (2) reclassification of knowledge, experiences, and attitude by factor analysis, (3) prediction of health behavior for prevention of pneumoconiosis by discriminant analysis. Knowledge, experiences, and attitude toward pneumoconiosis were classified into nine factors. Knowledge about pneumoconiosis were broken down to two factors and attitude to four factors, and valence, perceived severity were classified into each one factor. According to demographic, socioeconomic characteristics, and factors of knowledge, experiences, attitude about pneumoconiosis, about 62% of behavior of wearing respiratory protector was correctly discriminated. And by the same methods, about 81% of behavior of hospital visit at respiratory symptoms; cough, sputum, chest pain etc. was discriminated correctly.

Survival Rate of Hospitalized Coal Workers' Pneumoconiosis Patients: According to Characteristics at the Time of Hospitalization / 예방의학회지

The authors investigated mortality rate of hospitalized CWP(coal workers' pneumoconiosis) patients. Date, which was composed of age, date of hospitalization, date of death, and radiological findings(profusion of small opacity, type of large opacity, tuberculosis, emphysema, pneumothorax, and cardiac abnormality), was gathered from medical charts and chest x-ray films at the time of hospitalization of CWP patients. Among 738 CWP patients, that were entered survey differently and have followed different period, 160 CWP patients were died during different observational period. Mean value of observational period was 203 weeks, and mean age at hospitalization was 51 years. Because of short observational period, mean survival time could not found. There was statistically significant difference of mortality rate between group of small opacity and that of large opacity. In group of small opacity 5 year survival rate was 0.80 and in group of large opacity that was 0.73. And 80 percentile survival time was 57 months in group of small opacity and that was 40 months in group of large opacity.

Characteristics and Affecting Factors of Tinnitus in Noise Exposed Workers / 대한산업의학회지

OBJECTIVES: Tinnitus is a relatively common complaint of workers who are exposed to noise. The aim of the study was to investigate the prevalence and characteristics of tinnitus as well as the factors related to the prevalence of tinnitus. METHODS: A cross-sectional audiologic survey was combined with a questionnaire on tinnitus in a stratified random sample of 246 shipyard workers who had long-term exposure to noise. RESULTS: Forty seven had tinnitus, giving a prevalence of 19.1 percent. The tinnitus was the here and now in 44.7 percent of cases, bilateral in 51.1 percent, and caused sleep disturbances in 12.8 percent. The prevalence of tinnitus was highest in shipfitters and those with longer exposure duration.The workers with tunnitus had consistently higher hearing thresholds at both high and low frequencies than those with no tinnitus.The workers with tinnitus had a significantly higher prevalence of hearing disorders such as conductive hearing loss, a C5-dip, and NIHL.Multivariative logistic regression indicated that past history of ear disease, working and military service exposure to noise were independently associated with tinnitus. The adjusted odds ratio estimates for tinnitus were 3.0 times greater (95%CI 1.4-6.4) for the group with a past history of ear diseases,2.3 times greater (95%CI 1.0-5.0) for the military noise exposed group,and 4.5 times greater (95%CI 1.8-11.1) for the working noise exposed group. CONCLUSIONS: The results provide evidence that reports of tinnitus at the time of the annual audiometric testing may be useful in identifying workers at greater risk of developing significant shifts in their hearing thresholds. An awareness of the possible occurrence of tinnitus may encourage workers to cooperate more actively in a company's hearing conservation program.

Effect of Fibronectin on the Production of Nitric Oxide from Murine Peritoneal Macrophages / 대한산업의학회지

No abstract available.

A Study on the Psychological Symptoms of Hospitalized Pneumoconiosis Patients: Comparison with pneumoconiosis Examinees, Coal Miners, and Other Manual Workers / 대한산업의학회지

The purpose of this study was to investigate the effect of hospitalization and diagnosis of disease on the mental health of coal workers' pneumoconiosis patient. The study subjects were composed of four groups for comparison; hospitalized coal workers' pneumoconiosis, healthy coal miners, and railroad workers employed by government. About a hundred of respondents in each group were sampled by random. Mental health data were collected by symptom distress checklist 90 (SCL-90), and other characteristics were collected by interview with questionnaire administered trained interviewers in each respondents. Mental health dimension was classified into 9 dimensions; somatization, obsessive-compulsiveness, interpersonal sensitivity, depression, anxiety, hostality, phobic anxiety, paranoid, psychosis. And as total index, global severity index, positive symptoms total, positive symptom distress index were also computed. As a result there is difference of mean score of 9 symptom dimensions among four groups. The mean score of the examinees of depth diagnosis of the impressed coal workers' pneumoconiosis is the highest score in all 9 symptom dimensions. However in the hospitalized coal workers' pneumoconiosis scores of somatization, depression, anxiety, and phobic anxiety were still higher than that of healthy coal miners. And other symptom dimensions were not different from that of healthy coal miners.

The Effect of Working Noise Exposure and Military Background on the Hearing Threshold / 예방의학회지

OBJECTIVES: Impaired hearing is a prevalent occupational hazard, not only in industry, but also in the armed forces. In military life, noise has unusual characteristics, and constitutes a serious hazard to hearing. The aim of this study was to analyze the hearing threshold data in order to compare the hearing loss among shipyard workers, representing different workers, and a military service background. METHODS: A cross-sectional audiological survey, combined with a questionnaire study, was conducted on a stratified random sample of 440 shipyard workers, with long-term exposure to noise. The employees were divided into four groups, according to their working and military service backgrounds, in relation to their exposure to noise. RESULTS: As expected, the working and military noise exposure group (Group I) had significantly poorer hearing than the other groups. The high frequencies (2-8 kHz) showed the greatest difference in terms of poorer hearing in both ears. The prevalence of noise-induced hearing loss (NIHL) was highest in Group I. A logistic regression analysis was applied to determine the dependence of the NIHL in relation to age, smoking, drinking, working duration, ear protection, past history of ear diseases, and working and military service backgrounds, on the noise exposure. The important factors found to be related to the NIHL, in relation to noise exposure were: age, work duration, and working and military service backgrounds. The adjusted odds ratio estimates for NIHL in the right ear were 4.5 times greater (95% CI 1.7-11.6) for the military noise exposed group, and 7.9 times greater (95% CI 2.0-31.3) for the working noise exposed group than in the controls. The hearing thresholds at the pure-tone average and 4 kHz were significantly increased with age and work duration with both the working and military service backgrounds. CONCLUSIONS: From these results, specific preventive programs were planned, which should be assessed by epidemiological surveillance of the military noise exposed population.

Serum protein concentrations and electrophoretic patterns by categories of small opacity profusions in coal workers' pneumoconioses / 예방의학회지

The concentrations of serum proteins fractions and their electrophoretical patterns were investigated in 135 patients with coal workers' pneumoconiosis who participated in confirmative examination for pneumoconiosis in December 1989. Their radiographical profusions were classified as 1/0 or more. Agarose film and phosphoric acid-sodium hydroxide buffer(pH 8.6) were used for electrophoresis. Concentration of each protein fractions and electrophoretical patterns seemed to be equivalent to reference values. Serum alpah1- and beta-globulin concentrations, however, were significantly different(p<0.50) among categories of small opacity profusions and showed the lowest level in the group of category 1. Albumin concentrations decreased and alpha2-globulin concentrations increased significantly(p<0.05) in the group of complicated with pulmonary tuberculosis. gamma-globulin concentrations were not varied by category of profusions nor by pulmonary tuberculosis complication.

The Serum Alpha-antitrypsin Concentration of Coal Workers' Pneumoconiosis Patients / 대한산업의학회지

This study was performed to investigate associations between serum alpha(1)-antitrypsin(AAT) concentration and radiological categories of coal workers' pneumoconlosis(CWP), between AAT concentration and pulmonary complications such as tuberculosis and emphysema, and to study associations between AAT concentration and FEV(1.0)% in CWP patients, We classified 254 CWP patients in D Hospital into categories of small opacity profusion. And we selected 86 subjects by with or without emphysematous finding in each categories by proportional stratified sampling method. Semm AAT concentrations were quantkated by single radial immunodiffusion method, and the findings of chest radiographs were evaluated by radilogist. The results were as follows: 1. Serum AAT concentrations were not significantly different among groups of radiological categories of small opacities. 2. Complication of emphysema was associated with smoking habits sigmficantlyl(chi square=12.16, p<0,01). And AAT concentraLion was higher in smokers and ex-smokers than in non-smokers. Serum AAT concentration was significantly higher in the cases with emphysema than in the cdses without emphybema{p<0.01). 3. Serum AAT concentration of the group with active pulmonary tuberculosis was significantly higher than with inactive or without: pulmonary tuberculosis group(p<0.1). 4. Serum AAT concentration of the group with low FEV(1.0)% was significantly higher than with high or normal group(p<0.05).

Occupational Cancer in Korea in the 1990s / 대한산업의학회지

The proportion of cancer as a cause of death in Korean has been continuously increasing. In 2000, 24 %(59,020 of 247,346) of deaths were caused by cancer. Occupational exposure would have contributed to the development of some cancers. It would have accounted for more than 2,000 cancers in a year if 4% of all cancer or 10% of lung cancer was regarded as arising from the work environment. However, occupational cancer has not been reported as much as expected. The first case of occupational cancer reported officially was mesothelioma caused by asbestos exposure at an asbestos textile industry in 1992. Following the report, many cases of occupational cancers have been reported such as lung cancer due to exposure to asbestos, chromium, exhaust gases, coke oven emissions, and silica, as well as leukemia due to exposure to benzene or other solvent and bladder cancer arising from exposure to benzidine salts. The Health Examination for retirees has been conducted since 1992 in order to detect occupational cancer early in workers who have been exposed to 11 carcinogenic substances. However, to date no occupational cancer has been detected through the Retirees' Health Examination. The Korea Labor Welfare Corporation(KLWC) has referred 108 claims for occupational cancer to the Korea Occupational Safety and Health Agency(KOSHA) between 1992 and 2000. Thirty-three cases were accepted, including 14 cases of lung cancer, eight cases of hematopoietic cancer and six cases of mesothelioma. KLWC has accepted the claim for primary lung cancer developed with pneumoconiosis as an occupational cancer, of which there were 31 cases in 1999 and 61 cases in 2000. In conclusion, special attention is required to detect occupational cancer due to their long latency period and the fact they are usually found after retirement.

Concentrations of lead, iron and zinc in blood of coal workers' pneumoconiosis patients / 예방의학회지

Lead, iron, and zinc concentrations in whole blood were determined by atomic absorption spectrophotometry, using a simple one-step dilution procedure, which were measured in 3 groups, 98 officers unexposed to dust or to metal, 58 coal miners without pneumoconiosis, and 113 coal workers' pneumoconiosis (CWP) patients. The results were as follows; 1. The precisions (C. V.%) of lead, iron, and zinc in blood were 12.65+/-6.95%, 1.47+/-1.25% and 6.35+/-3.34%, respectively. 2. Lead and zinc in blood showed the log-normal distribution unlike iron in blood which showed normal distribution. 3. Lead, iron, and zinc concentrations in blood of 3 groups were follows. There was significant difference of concentration far zinc in blood by groups statistically. 4. The difference of lead, iron, and zinc concentrations in blood was not significant (p>0.05) by profusion on chest radiographs.

The Prediction Model of the Number of Industrial Injured Persons Using Data Mining / 대한산업의학회지

OBJECTIVES: This study is to see the transition and pattern of the industrial iureal worker, and to develop the prediction model. METHODS: The data of the study are based on the samples from data-warehouse of Occupational Safety & Health Research Institute and are summed monthly from Jan 1986 to Dec 1999. This study data used data mart and Meta data from DW in KOSHA. The prediction model of the injured worker in Industry is designed by using a winters time series method after data preparing (i. e. sample, explore, modify) from DW. RESULTS: Thls predicted model obtained Winters-method multiplicative in exponential smoothing among applied all models, after the tlme series (total 163 months). It showed that the prediction power was 95.5 %. CONCLUSIONS: In the process of exploring the data, totally the rate of industrial injureal workers reduced, and in the yearly circulation, in February and September the number is the lowest but in June, July, October and November the higher. The number of monthly average injureal workers is 8709 (95 % confidence interval 8277, 9140). From the developed prediction model, since Aug 1999 the industrial injureal worker reduced rapidly in Dec 1999 and first period of 2000. But In second period of 2000 the number of the injured workers is increasing. To conclude, as the total economic situation is becoming better in 2000 than In 1999, its is supposed that the injured workers will increase more than the predictive injured workers because of the increase of production rate and labor force.

Development of Physiologically Based Pharmacokinetic Model for Several Volatile Organic Compounds / 대한산업의학회지

Recently physiologically based pharmacokinetic (PB-PK) model has important role in industrial and environmental health. One of problem in application of PB-PK models is that they have uncertainties that is due to different input parameters according to authors. In order to develope a PB-PK model that hag good validity, the effect of several input parameters on simulation results was studies. Chemicals studied were perchloroethylene, toluene and styrene. Simulation of alveolar concentration, blood concentration and urinary metabolites was performed for three solvents, respectively. Input parameters discusses were physiological parameters, metabolic parameters and partition coefficient of chemicals. By comparing simulation results according to several pairs of parameters with experimental data, input parameters that showed best fit were decided.

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).

Reading Agreement of Pneumoconiosis on Simple Chest Films / 대한산업의학회지

No abstract available.

Analysis of Occupational Disease by Approved Korea Labor Welfare Corporation in 1999 / 대한산업의학회지

OBJECTIVES: The purpose of this study is to analyze the characteristics of occupational diseases listed by Korea Labor Welfare Corporation(KLWC). METHODS: Using the database of the KLWC, we collected 575 approved occupational disease cases occurring between 1 January and 31 December 1999 and approved by the thirtieth June in 2000. We investigated the characteristics(sex, age, occupational history, kinds of occupational disease, exposure material, type of enterprises, etc.) of occupational disease using a mail survey and telephone interviews. RESULTS: Men accounted for 88.9 %(511 workers) of the approved cases. 56 cases(9.7%) died of occupational disease. The most common age group was 50~59 years of age(n=217, 37.7 %). The proportion of workers with grater than ten years disease related working condition exposure were 195(49.0 %). The majority of diseases were respiratory problems(211 workers, 22.4 %), occupational hearing loss(149 workers, 25.9 %), infectious disease(69 workers, 12.0 %), intoxication(60 workers, 10.4 %), skin disease(29 workers, 5.0 %) and cancer(17 workers, 3.0 %). The causal hazardous agents were dusts(209 cases, 36.3 %), physical agents(157 cases, 27.3 %), chemical agents(89 cases, 16.3 %), biological agents(82 cases, 14.3 %) and workrelated agents(34 cases, 5.9 %). The major types of enterprise were manufacturing(262 workers, 45.6 %), mining and quarrying(174 workers, 30.3 %), public administration(42 workers, 7.3 %) and the health care industry(28 workers, 4.9 %). The kinds of job included craft and related trades workers(285 workers, 49.6 %), plant or machine operators and assemblers(139 workers, 24.2 %), elementary occupations(72 workers, 12.5 %) and professionals(28 workers, 4.9 %). CONCLUSIONS: We were able to elucidate the kinds of occupational disease and the characteristics of workers through this study. Many approved cases occurred among nonmanufacturing and non-mining workers and the kinds of disease were varied. This suggests that management policy must be established to prevent occupational disease occurring among workers in the above type of industries.