The Association of the Serum Magnesium with Hearing Loss Among Noise Exposed Male Workers / 대한산업의학회지

OBJECTIVES: This study was conducted to investigate that the chronic noise exposure is associated with decreased serum magnesium concentrations and evaluate whether decreased serum magnesium is associated with noise induced hearing loss. METHODS: One hundred seventy-eight male workers exposed to noise were selected and classified three groups by the degree of hearing loss. Hearing threshold levels were less than 30 dB at 1,000 Hz or less than 40 dB at 4,000 Hz in group I, more than 30 dB at 1,000 Hz or more than 40 dB at 4,000 Hz and 15 dB and less of pure tone average(PTA: (500 Hz+1,000 Hz+2,000 Hz)/3) in group II, more than 30 dB at 1,000 Hz or more than 40 dB at 4, 000 Hz and over 15 dB of PTA in group III. RESULTS: Serum magnesium concentrations were 2. 42+/-0. 26 nc/dt in group I, 2. 35+/-0.23 mg(dl in group II, 2.26+/-0.24 ne/dl in group III, respectively and significantly different between group I and group III (p<0. 01). It was negatively correlated with duration of the noise exposure as correlation coefficient(r) of -0.194 (p<0.05). Analysis of the multiple regression on hearing threshold levels showed that serum magnesium, diastolic blood pressure, duration of the noise exposure were statistically significant at 4,000 Hz(p<0.05). While only age was statistically significant at 1,000 Hz(p<0.05). CONCLUSIONS: These results suggest that chronic noise exposure may induces decrease in serum magnesium concentrations and that its decreased concentration is related with noise induced hearing loss.

Neurobehavioral Effects of Low Level Lead-exposed Workers at CRT(Cathode Ray Tube) Manufacturing Factory / 대한산업의학회지

To assess neurobehavioral effects of 48 low level lead-exposed workers in CRT manufacturing factory, simple and choice reaction time test with NTOS (Neurobehavioral Tests for Occupational Screening), digit symbol and digit span with K-WAIS (Korean Wechsler Adult Intelligence Scale), and SCL-90-R (Symptom Check List 90 revised) was examined. These screening test battery reflect 3 psychological domain; psychomotor, short term memory, and symptom. Average blood lead level was 17.7 microgram/dl and mean exposure duration was 5.6 years. Nobody exceeded blood lead level over 40 microgram/dl, the guideline. We divided workers to two group, shorts-term exposed group(< or = 5 years) and long-term exposed groups 5 years) for analysis. ANCOVA model of simple reaction time, hostility, phobic anxiety, somatization were statistically significant and coefficient of independent variable of exposure duration was also significant. MANCOVA model of SCL-90-R was significant, too. The results of this study were consistent with previous study; symptoms were early neurobehavioral effects of low level lead exposure. And this study showed that current blood lead level as independent variable was able to mask the early neurobehavioral effects.

A Computerized Scoring Method of The Hahn Double 15 Hue Test / 예방의학회지

The Hahn double 15 hue test is used for social and vacational aptitude test to separate strongly and mildly affected subjects among the colour vision defective persons, detected using colour vision test. However, the assessment of colour vision defect type and severity is based on the hue confusions which are represented diagrammatically on Hahn double 15 hue score sheet, this qualitative assessment of the test results have not provide a numerical score suitable for mathematical analysis. This paper presented a new proposal for quantitatively scoring the Hahn double 15 hue test based on those hue confusions made by the subject. With this program large numbers of double 15 hue test results can be processed easily and rapidly, and program helps to compare the severity of specific type colour vision defect and monitor acquired colour vision defect which has various disease process, continuously.

Knowledge, Attitude and Practice according to Types of Occupational Health Management / 예방의학회지

The first purpose of this study was to compare the mean Knowledge, Attitude & Practice(KAP) scores concerning major occupational Health between two types of occupational health management in small & medium-scale textile factories. Sample number was 1,138 workers. In small & medium factories with 300 workers or less, they have two alternatives for occupational health management; Individual Health Management or Vicarious Health Management. The second purpose was to determine if there was a relationship between duration of Vicarious health management and mean kap scores for 694 workers from the Vicarious Health Management group. We used self-administered questionnaires for measuring KAP. The results of this study were; 1. There was significant difference concerning all socioeconomic & occupational variables(gender, age education level, marital status, Blue/White collar, working duration of present factory, working duration of total factories) except for shift. 2. There was no significant difference of mean scores of Knowledge and attitude between the Individual Health Management Group and the Vicarious Health Management. But, the mean score of Practice was significantly different. 3. According to multiple regression analysis, the mean score of Knowledge significantly increased with age, education level, working duration of all factories increased. The mean score of Attitude significantly increased with age, education level and married. The mean score of Practice significantly increased with age, education level, working duration of all factories, married and men. 4. In conclusion, The type of Health management did not significantly affect the mean KAP scores concerning major occupational Health problems. 5. But, the Duration of Vicarious Health management significantly increased the mean KAP scores.

Relationship of Physical Fitness with Age and Body Fat, Work Pattern, Life Style among Male Workers of an Electronic Manufacturing Company / 대한산업의학회지

This is pilot study to evaluate the relationship of physical fitness with age, body fat, work pattern and life style among 20-9 aged male workers (n=417). Physical fitness was measured by maximum oxygen uptake, forced vital capacity, 1 second forced expiratory volume, grip strength, back strength, sit ups and trunk flexion. Life style was self-reported on a questionnaire about regular exercise, smoking, alcohol consumption, coffee consumption, degree of stress, and percent of body fat measured by bioelectrical impedance fat meter. Age was significantly and negatively related to physical fitness except grip strength. Obesity was next to most significant factor for physical fitness, it was associated with maximum oxygen uptake, grip strength, back strength, trunk flexion. Regular exercise was associated with maximum oxygen uptake. Others was insignificantly related to physical fitness. Performance of physical fitness test was significantly correlated with age, obesity and regular exercise.

Trace of Occupational History on Lung Cancer Patients / 대한산업의학회지

The relationship between occupation and risk of lung cancer was analyzed in hospital based case-control study conducted in Taegu on 168 patients with histologicatly confirmed lung cancer and age group (30-39, 40-49, etc) and sex frequency-matched 168 controls admitted into hospitals for other internal medicine problems. A self administered questionnaire was used to obtain occupation, resident environment, smoking histories and specific agent exposure histoy. The conditional logistic regression was used to estimate odds ratio for age group and sex frequency matched, after controlling for smoking status (non smoker, exsmoker, current smoker) Significant association was observed for farmer[odds ratio(OR), 1.84 , 95% confidence interval(CI), 1.16-2.94], briquette stove users(OR, 3.0 , 95% CI, 1.06-8.25), agricultural chemicals users[0R, 2.14 , 95% CI, 1.35-3.37], and welding/fume exposures[0R, 10.56 ;95% CI, 1.07~103.90]. Although there were elevated risks associated with production, home industry, transportation/storage/communication, lodgement/food worker and construction, none were statistically significant.The effect of smoking was showed significantly increased risk for exsmoker [0R, 4.50 ,95% CI, 1.99-10.16] and current smoker [OR, 3.98 , 95% Cl, 1.88-8.45] As results, although smoking is important risk of lung cancer, occupation and resident environment are showing association of lung cancer. So further evaluation is necessary for occupation risk and take preventive measures.

Incidence of the Needle-Stick Injuries in Medical Students Among Clinical Training / 예방의학회지

A questionnaire survey was conducted to assess the experience of the needle stick injuries in 144 seniors of a medical school during the previous 10 months. one hundred and five of them (73%) had responded. About sixty-nine percent(72 cases) of the respondents had suffered at least one injury and there had been 129 injuries in total. Seventy-eight(56.6%) of the injuries took place at the time of the venipuncture. The emergency and operating room incurred 76.7 % and 23.3% of the injury, respectively. Injuries with bleeding account for 50.4%. None of the respondents was systematically educated about the prevention of injury. This survey shows that the needle-stick injury is a great risk for the medical students' health, and that educational effort for its prevention is warranted.

Selection of Testing Frequency in Bone Vibrator of Audiometer for Measurement of Vivration Perception Threshold / 대한산업의학회지

Both to determine testing frequency in bone vibrator of audiometer for measurement of vibration perception threshold(VPT) and to evaluate factors influencing VPT, ninty seven healthy adults were tested on their second metacarpal head of both hands, at 250Hz, 500Hz, 1,000Hz and so on. Measures of the VPTs at 1,000Hz were excluded in analysis because frequency 1,000Hz was not recognized as a vibration sense. Mean and standard deviation(S.D.) of the VPTs in the both hands measured at 250Hz were 19.9+/-6.7dB, 21.0+/-7.3dB, respectively and at 500Hz were 33.6+/-8.3dB, 34.9+/-8.1dB, respectively. Both mean and S.D. tended to be lower at 250Hz than 500Hz, and mean differences of VPTs between the left and the right hand at the both frequencies appeared statistically significant (p<0.01). VPTs were significantly correlated with each other (p<0.01). Age was positively correlated(p<0.001) with VPTs and education was negatively(p<0.01). Multiple regression analysis showed that age was the only factor influenced on VPT. These results suggest that, when using the bone vibrator of audiometer for measurement of VPT, the frequency 250Hz as a testing frequency may be more useful than frequency 500Hz, and VPT should be measured on both hands.