Noise pollution, both in the environment and in the workplace, has been recognized as a major health hazard - one that can impair not only a person's hearing but also his physical and mental well-being. As industrialization progresses, the prevalence rate of occupational diseases is increasing, especially hearing loss, which has the highest prevalence rate among the occupational diseases. The major cause of noise is the construction of various large industries without any regulation of noise sources. Therefore, we must establish an enactment to control mechanical noise sources as soon as possible. For the purpose of controlling the noise source, we must have exact data about such things as the sound level, the frequency of the peak sound and the revolutions per minute (r.p.m.) of the machine (a measure of the power of its motor). This study was undertaken in order to define the noise characteristics, the power of the machine's motor, the change of the sound level and the peak sound as the r.p.m. increases, and the permissible exposure time, The sample size of this study was 74 machines at 11 plaints in 6 industries. The results are as follows : 1. The breakdown of the types of mechanical noise noted was : 63.6% continuous normal sound, 26.9% intermittent sound, 4.7% continuous repeating sound and 4.6% impulsive sound. 2. With respect to the type of industry, the overall sound level was the highest in the mechanical industry, with 103+/-2.8 dB(A), and lowest in the textile industry, with 89.2+/-1.43 dB(A). 3. With respect to the type of machine, the highest sound level was 124 dB(A) caused by Gauzing(II), in the mechanical industry, and the lowest was 76 dB(A) caused by Attachment (Jup Check) (I) in the timber industry. 4. The shortest permssible exposur time to gauzing(II) in the mechanical industry was less than 15 minutes. 5. Among 74 machines, 68.2% of the peak sound was situated in the high frequency range (52.7% at 2 KHz and 1.4% at 8 KHz). 41.8% of the peak sound was in the middle frequency range (4.1% at 250Hz, 14.8% at 500Hz and 22.9% at 1KHz). 6. If one machine had two motors or more, the peak sound was shifted to the low frequency range. 7. As the r.p.m. increased, the overall and peak sound levels increased without any change of the frequency of the peak sound. 8. whenever the machines had the same king and the same r.p.m., the overall and peak sounds were changed by the physicochemical characteristics of the raw materials and the management.
Hearing ; Hearing Loss ; Noise* ; Occupational Diseases ; Prevalence ; Sample Size ; Textile Industry ; Industrial Development

OBJECTIVES: This research was intended to verify hepatic effect of simutaneously combined exposure of nickel chloride and cadmium chloride with IPRL(Isolated Perfused Rat Liver) method. METHODS: AST(aspartate aminotransferase), ALT(alanine aminotransferase), LDH(lactate dehydrogenase) and perfusion flow rate were used as the indicator of hepatotoxicity and oxygen consumption rate were used as the indicator of viability. 300(+/-50) g weighted rats were allocated randomly to each group (control group, 50 microM 200 microM separately exposure group of NiC1, and CdC1, simultaneously combined exposure group of NiC1 and CdC1) by 5, totally 35. Buffer which got out of liver was sampled and then biochemical indicator of hepatotoxicity was measured. In order to verify difference among groups, two way repeated ANOVA was used. With comparing mean summation of separate exposure group with mean of simultaneous exposure group, possibility that combined effect could be synergistic effect was verified. RESULTS: AST, ALT, LDH increased in both of separate exposure group and simultaneous exposure group. Perfusion flow rate and oxygen consumption rate decreased but statistically significant difference among groups was not found, In each exposure group, AST, ALT, LDH, oxygen consumption rate of simultaneous exposure group increased more than sum of separate exposure group after any sampling time. CONCLUSIONS: It was found that simultaneous combined effect could be synergistic effect through the biochemical indicator of hepatotoxicity.
Animals ; Cadmium Chloride ; Cadmium* ; Liver ; Nickel* ; Oxygen Consumption ; Perfusion ; Rats*

The effects and roles of social support and stressors (stressful life events and chronic strains) on psychosocial distress were examined in a model with data from a sample of the white-collar workers (N = 416) in Korea. The findings of this study present that mean levels of psychosocial distress were higher' in the female, youth, unmarried and divorced, and low economic status (monthly income). The analysis also shows that, as expected, stressful life and chronic strains as stressors are positively related to occurrence of psychosocial distress, and social support is negatively related to psychosocial distress. Further, the contribution of social support to predicting psychosocial distress is greater in magnitude than that of stressful events, chronic strains, and sociodemographic variables. There is no evidence that social support buffers the impacts of stressors on psychosocial distress, rather social support takes a role of main or direct effects on psychosocial distress. Therefore, the strength of the social support is an important and meaningful strategy to prevent from stress and mental, physical illness.
Adolescent ; Buffers ; Divorce ; Female ; Humans ; Korea ; Life Change Events ; Single Person

Our study was designed to identify the difference in the mental health status among hospitalized patients due to occupational diseases and accidents and pre-employment physical examinees, and to identify the relationship between mental health status and socio-demographic variables, and to provide information useful to non-psychiatric clinicians in caring of such patients. Samples were comprised of 189 pneumoconiotic patients, 132 industrial accident-induced patients and 122 pre-employment physical examinees who were interviewed with 90-item symptom cheklist(SCL-90). The following results were obtained: 1) Mean scores of symptom dimension on socio-demographic subgroup showed higher tendencies in older aged, male, lower educated, miner, married, mining residence, and pnemoconiotic patients. 2) Mean scores of total samples on all symptom dimensions were as follows in the order of their magnitudes; Depression, Somatization, Obsessive-compulsive, Anxiety, Psychoticism, Interpersonal sensitivity, Phobic-anxiety, Hostility, and Paranoid ideation. 3) The highest mean scores on each socio-demographic subgroup were as follows; Depression in younger aged and Somatization in older aged; Depression in male Somatization in female; Somatization in lower educated and depression in higher educated; Somatization in miners and depression in non-miners; Somatization in married and Depression in unmarried; Depression in all kind of residences; Somatization in patients and Depression in pre-employment physical examinees(normal). 4) In consequence of stepwise multiple regression, the important socio-demographic variables were age, occupation, diagnostic classification, and residence. Age was the most important variables in Somatization, Depression, Obsessive-compulsive, Anxiety, Phobic ideation, and Psychoticism. Occupation was the most important one in Interpersonal sensitivity and Hostility and also had significant relationships with all symptom dimensions.
Anxiety ; Classification ; Depression ; Female ; Hostility ; Humans ; Male ; Mental Health* ; Mining* ; Occupational Diseases ; Occupations ; Single Person

OBJECTIVE: To verify the separate and combined effects of cadmium and nickel on blood pressure in rats. METHODS: Following the daily administration of cadmium chloride(CdCl2) and nickel chloride(NiCl2) to rats both individually and in combination with intraperitoneal injection method for one week, systolic blood pressure of the tail was measured at 1 day and 5, 10, 20, 30 days after administration. Each substance was injected into the rats with 0.1 mg/kg bw and 1.0 mg/kg bw concentration. RESULTS: After 0.1 mg/kg bw CdCl2 was injected, a statistically significant difference was found as compared with the control group(only saline) after 1, 5 and 10 days. After 0.1 mg/kg bw NiCl2 was injected, a statistically significant difference was not found compared with the control group. After 0.1 mg/kg bw CdCl2 and 0.1 mg/kg bw NiCl2 were injected simultaneously, a statistically significant difference was found as compared with the control group after 1, 5 and 10 days and compared with 0.1 mg/kg bw CdCl2 group after 5 days and as compared with 0.1 mg/kg bw NiCl2 group after 5 and 10 days. After 1.0 mg/kg bw CdCl2 was injected, a statistically significant difference was found as compared with the control group after 1, 5, 10 and 20 days. After 1.0 mg/kg bw NiCl2 was injected, a statistically significant difference was found as compared with the control group after 1 day and 5 days. After 1.0 mg/kg bw CdCl2 and 1.0 mg/kg bw NiCl2 were injected in combination, a statistically significant difference was found after 1, 5, 10, 20 and 30 days as compared with 1.0 mg/kg bw CdCl2 after 10, 20 and 30 days and as compared with 1.0 mg/kg bw NiCl2 after 5, 10, 20 and 30 days. CONCLUSION: It was found that the effect of CdCl2 on blood pressure was much more than NiCl2 and a high concentration CdCl2 and NiCl2 in combination delayed the recovery of blood pressure.
Animals ; Blood Pressure* ; Cadmium Chloride ; Cadmium* ; Injections, Intraperitoneal ; Nickel* ; Rats* ; Tail

The effects of multiple exposures to pesticides on plasma cholinesterase(ChE) activities and urinary p-nitrophenol excretion were evaluated in rats. Rats were received single dose i.p. with LD50/100(mg/kg) of organophosphorous(OP), organophosphorous-organochroline(OP-OC), organophosphorous-carbamate(OP-CAB), organophosphorous-organoarsenate(OP-OA) pesticides for 4 consecutive days. In repeated administration of pesticides, plasma ChE activities were decreased, but urinary p-nitrophenol were increased after the first injection and then decreased gradually. The recovery rates of ChE activities and p-nitrophenol excretion at 48 hours after the fourth infection were delayed in comparison with the baseline value of 24 hours before the first injection. Statistical significances were found between OP and other groups except OP-OA group after the second injection in plasma ChE activities, but in urinary p-nitrophenol excretion there was statistical significance only between OP and OP-CAB.
Animals ; Cholinesterases* ; Pesticides* ; Plasma* ; Rats*

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.
Coal* ; Dyspnea* ; Humans ; Korea* ; Logistic Models ; Male ; Multivariate Analysis ; Pulmonary Artery ; Pulmonary Heart Disease ; Risk Factors ; Smoke ; Smoking ; Thorax

Information on work stress and mental health status of industrial workers was required for optimum staffing and health care management. This study dealt with the relationship between mental health status examined by PSI(psychiatric symptom index) and socio-demographic variables. Especially this study attempted to find relevant determinants of the stress and mental health through multiple stepwise regression analysis based on data obtained from 687 occupational workers. The findings of this study were as follows; Mean scores of symptom dimension were higher in youth, female, more educated, unmarried and divorced, and workers in the noisy condition and short duration in job. And it showed high scores in long duration in job for anxiety; college educated for anger; unmarried for cognitive disturbance. The factors affecting the mean scores of psychiatric symptom index were varied according to the types of symptom; age, sex and duration in job for anxiety; age, sex, living with parent, education and marital status for anger; sex and marital status for depression; noisy condition and sex for cognitive disorder.
Adolescent ; Anger ; Anxiety ; Delivery of Health Care ; Depression ; Divorce ; Education ; Female ; Humans ; Marital Status ; Mental Health* ; Parents ; Single Person

By implementing epoch-making policies for industrial promotion, the national economy has made a remarkable development. As a result of such economic growth, industrial accidents and occupational diseases have become a serious problem in Korean society. In the presidential order for the execution of the Korean Labor Standard Law, neuritis and other diseases stemming from health impairments due to vibrations in industrial processes are designated to be dealt with as vibration diseases. In the case of vibration disease, industrial accident compensation is not effectively paid. In order to investigate the vibration hazards of rock-drill operation, the authors studied the subjective symptoms and performed physical function tests on a total of 79 persons (vibration exposed group) who used rock-drills, and 39 persons (control group) who did not use rock-drills at anthracite mines. The results of the physical function test were as follows : 1. The right hand was more affected by white finger than the left hand. 2. Independent variables such as duration of rock-drill operation, age, drinking and smoking were identified as statistically significant factors for the occurrence of white finger. 3. In the pain sense threshold, the group with Raynaud's phenomenon showed a statistically higher level than that of the control group. 4. The skin temperature of the group with Raynaud's phenomenon was lower than that of the control group. The recovery time of skin temperature after cooling was delayed compared with the value of the control group.
Accidents, Occupational ; Coal* ; Compensation and Redress ; Drinking ; Economic Development ; Fingers ; Hand ; Humans ; Jurisprudence ; Neuritis ; Occupational Diseases ; Skin Temperature* ; Skin* ; Smoke ; Smoking ; Vibration

This study was conducted to understand health status by general characteristic, and to find out relationship between social support and worker's health status. Health status was measured using SF-36(Medical Outcome Study Short Form 36), a 36 item self administered Instrument. The finding of this study were as follow; Mean scores of health status by sex were higher in male. The younger worker reported good health on physical functioning and role limitation-physical than did the older worker, but the older worker reported good health on social functioning and mental health. Mean scores of health status were higher in high income and white worker. When the relationship between social support and health status, social functioning, role limitation-emotion, mental health, vitality, general health were significantly related. Therefore we reviewed the evidence that socio-economic condition are associated with health status in this study, and that the strength of the social support was a important to maintain health.
Humans ; Male ; Mental Health ; Outcome Assessment (Health Care)