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Volume 28(1); March 1995
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Original Articles
A Study on Workers Exposed to Diatomaceous Earth Dust and Development of Pneumoconiosis in a Diatomite Factory.
Hyun Suk Lim, Sung Soon Kim, Won Jae Lee
Korean J Prev Med. 1995;28(1):1-12.
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AbstractAbstract PDF
Diatomaceous earth, quarried from the remains of aquatic plants deposited millions of years ago, continues to be a very important raw material with many industrial uses. In its natural state diatomaceous earth is an amorphous silica with no crystalline pattern. For many uses, however, it is calcinated and calcination converts a portion of the amorphous silica to a crystalline form, cristobalite which is far more fibrogenic. In a factory which produces calcinated diatomaceous earth, seven workers were proved as pneumoconiosis on l991 and 1992. Authors reviewed medical chart and current status of them. Authors also examined thirty one subject from the factory with questionnaire, physical examination, spirometry and chest radiography on August 13th 1993. The radiographs were independently interpreted by two radiologists and their findings were classified by International Classification of Radiography of pneumoconiosis(lLO, 1980). Total and respirable dust of diatomaceous earth were measured on october 1993. The results were as follows: 1.Of 31 workers, 6 (19.4%) were diagnosed as diatomaceous earth pneumoconiosis. There was an increasing tendency in prevalence of pneumocoiosis as the duration of dust exposure gets longer. 2. There were no significant differences in age, smoking rate, alcohol drinking rate, and pulmonary function test results between cases and non-cases. 3. The means of total dust exposures at flour manufacturing, fire brick grinding and packaging, ceramic raws packaging processes exceeded Korean and AGGIH standards, 10mg/m3. Above results suggest that engineering controls, periodic environmental and medical surveillance are important for preventing pneumoconiosis in the diatomite factory.
Summary
An Epidemiologic Study on Occupational Dermatosis Associated with Mites.
Hyun Sul Lim, Ji Yong Kim, Hae Kwan Cheong, Yeol Oh Sung, Han Il Ree
Korean J Prev Med. 1995;28(1):13-26.
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AbstractAbstract PDF
An outbreak of dermatosis occurred in a livestock fodder factory at Kyongju in May 1994. Authors conducted a questionnaire survey on 60 workers in the factory and a dermatologist examined their skin lesion. Authors also collected mites and identified them. The obtained results were summarized as follows; 1. Twentyeight cases of dermatosis were identified with attack rate of 46.7%. Attack rate was not different by department, age, sex, educational level and employment duration. Attack rate was 67.5% in productive worker and 5.0% in clerical workers (p<0.01) but was not significantly different between departments among productive workers (p>0.05). 2. Three cases among 28 dermatosis cases and one subject among 32 non-cases had a history of same dermatosis last year. Only one of dermatosis cases had a history of dermatosis among family members. History of other skin lesion and allergy was very rare in both cases and non-cases. 3. Skin lesions of the cases were rice-sized erythematous papules or vesicles with a central biting point. Onset date of dermatosis was between May 1 and June 10. Duration was from one day to more than 30 days. Skin lesion was most frequent at the back(75.0%). and also observed at the arms(64.3%). abdomen(60.7%), legs(57.1%), chest(32.1%) and neck (25.0%). Skin lesion was aggravated while workers are sweeping the floor(35.7%), working at the workplace(21.4%) and in bed at night(28. 6%). 4. Total l,637 mites were collected and identified into 3 suborder, 7 families and 17 species. Dermafophagoides farinae was most frequent Nnd most of the species identified were blood sucking mites. Authors concluded that the outbreak of dermatosis was brought about by mite-bites and grain beetle parasitizing Acarophenax tribolii was the most suspected species. Further studies to identify the specific species causing dermatosis and route of import are needed.
Summary
Effect of Mercury Chloride on Humoral and Cell-mediated Immune Responses in Mice.
Jung Ho Youm
Korean J Prev Med. 1995;28(1):27-42.
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AbstractAbstract PDF
The in vivo and in vitro humoral and cell-mediated immune responses of lymphocytes of BALB/c mouse exposed to mercury chloride(HgC12) were investigated. In vitro exposure of the splenocytes to mercury chloride produced overt cytotoxicity in 3 hours period. The IC50(the concentration required to inhibit a splenocyte viability by 50%) for mercury chloride was >0.1mM for cytotoxicity. In vivo mercury chloride exposed mice were significantly depressed delayed type hypersensitivity(DTH) response to sheep red blood cells(SRBC) in a dose-dependent manner compared with control group. Mercury chloride inhibited the proliferative responses of splenocytes to lipopolysaccharide. pokeweed mitogen, concanavalin A and phytohemagglutinin in a dose-dependent manner. Hemagglutinin response to SRBC in mercury chloride exposed mice was significantly depressed in a dose-dependent manner compared with control group. After 7 weeks of mercury chloride exposure in vivo. mercury chloride induced an increase of nonspecific serum IgG1 and IgE levels in BALB/c mice.
Summary
Study on the Pulmonary Function in Welding Fume Exposed Workers.
Young Seoub Hong, Byoung Gwon Kim, Sung Ryul Kim, Do Won Dam, Jung Man Kim, Kap Yull Jung, Joon Youn Kim
Korean J Prev Med. 1995;28(1):43-58.
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AbstractAbstract PDF
In order to study the effect of welding fume exposure upon the pulmonary function test, we examined 131 shielded arc welding workers, and 152 CO2 arc welding workers as cases and 172 control workers for their general characteristics, and forced vital capacity (FVC), forced expiratory volume in one second (FEV1.0) forced expiratory volume in one second as a percent of FVC(FEV1.0%), and maximal mid-expiratory flow (MMF) were obtained from in the spirogram. In shielded arc welding group and CO2 arc welding group, FVC, FEV1.0, FEV1.0%, and MMF were significantly decreased than control group, especially marked in the MMF finding. The distribution of workers below normal range was as follows: in the shielded arc welding group, 2 workers(l.5%) for FVC, 17 workers(13.0%) for FEV1.0, 5 workers(3.8%) for FEV1.0%, 28 workers(21.4%) for MMF, and in the CO2 arc welding group, 3 workers(2.0%) for FVC, 25 workers(16.4%) for FEV1.0, 8 workers(5.3%) for FEV1.0% and 37 workers(24.3%) for MMF, and significant increase by exposure duration was found in MMF. The distribution of workers who had ventilation impairment was as follows: 5 workers(3.8%) for obstructive type, 2 workers(l.5%) for restrictive type in the shielded arc welding group and, workers(4.6%) for obstructive type. 2 workers(l.3%) for restriotive type, and 1 worker(0.6%) was combined type of the CO2 arc welding group. In the respect of these results the significant pulmonary function and ventilatory impairment were observed in welding fume exposed workers who had not abnormal finding in chest X-ray, and MMF considered as the most sensitive pulmonary function index by welding fume exposure. Therefore even if it is hard to doing pulmonary function test in the first health examination of workers according to the Industrial Safety Health Act in the welding fume exposure workers. it is desirable to consider doing PFT. Also evaluating the ventilation impairment, it is necessary, to observe the change of MMF that marker of effort-independent portion.
Summary
A Study on Food Intake and Associated Factors of the Urban Poor Elderly.
Bong Soo Cho, Don Kyoun Kim, Su Ill Lee, Byung Mann Cho, Yeung Ook Kim, Kwang Wook Koh
Korean J Prev Med. 1995;28(1):59-72.
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AbstractAbstract PDF
This study was carried out to analyse the food intake and associated factors of the urban poor elderly by comparing poor district, Unbong rental apartment in Bonsong 2 dong with other areas in Pusan. 135 elderlies(men 36, women 99) in Unbong rental apartment 136 elderlies(men 45, women 91 ) in the other areas were investigated during the period of March to August in l994. The assumption that the study area represented poor district was satisfied because the age and sex distribution was not significantly different, and the income of the study area was significantly lower than that of the control area. The variables of hospitalized in previous 12 month, gastrointestinal problem, alcohol drinking, cigarette smoking did not differ significantly. But the variables of chronic disease, take medicine, perceive, vitamin supplement differed significantly between two groups. Therefore some factors associated with health state in the study area are worse than those of the control areas. At most of all variables, nutrients intake of the study area did not reach the recommended dietary allowances(RDA) for Koreans, and that nutrient intakes of the study area were significantly lower than those of the control area. The hypothesis of this study that nutrient status depends on economical status was proved. As for the score of nutritional knowledge, the study area was significantly lower than the control area. But as for the score of nutritional behavior, two areas were not significantly different. The latter is counter result of our hypothesis, owing to the effect of the confounding factors including education etc. As for the correlation of variables, not only economic status and educational level, but the score of nutritional knowledge effects strongly on nutrient status in the study area, the poor district. Therefore, adequate nutritional education to the elderly in the poor district should be considered.
Summary
Lead Level in Blood, Scalp Hair and Toenail of Elementary Schoolchildren.
Jae Uk Kim, Jung Jeung Lee, Chang Yoon Kim, Jong Hak Chung
Korean J Prev Med. 1995;28(1):73-84.
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AbstractAbstract PDF
This study was conducted to measure the lead level in the blood, scalp hair and toenail of the elementary schoolchildren and assess the relationship among those samples. Lead concentration of the blood, scalp hair and toenail was measured for l00(male 50, female 50) fourth grade elementary schoolchildren in Taegu city. The mean lead level in the blood, scalp hair and toenail was 6.00+/-2.44 microgram/dl, 6.28+/-3.54 microgram/dl 6. 68 and 7.33+/-3.18 microgram/g. The mean lead level in the blood of schoolboys was 6.43+/-2.77 microgram/dl and that of schoolgirls was 5.59+/-2.01 microgram/dl. The mean lead level in the scalp hair of schoolboys was 7.66+/-2.97 microgram/dl and that of schoolgirls was 6.88+/-3.54 microgram/g. The mean lead level in the toenail of schoolboys was 8.19+/-3.5 microgram/g and that of schoolgirls was 6.47+/-2.52 microgram/g and their difference was statistically significant. In schoolboys, the correlation coefficient between the lead level in the blood and scalp hair was 0.4909, and the data were fitted best by the regression equation Y=0.5255X+4.2810, where Y and X are scalp hair and blood concentration. In schoolgirls the correlation coefficient between the lead level in the blood and scalp hair was 0.3778, and the data were fitted best by the regression equation Y=0.6655X+2.9632, where Y and X are scalp hair and blood concentration. In schoolboys. the correlation coefficient between the lead level in the blood and in the toenail was 0.5533, and the data were fitted best by the regression equation Y=0.7076X+3.6472, where Y and X are toenail and blood concentration. In schoolgirls the correlation coefficient between the lead level in the blood and in the toenail was 0.2738, and the data were fitted best by the regression equation Y=0.3431X+4.5570 where Y and X are toenail and blood concentration. In schoolboys, the correlation coefficient between the lead level in the scalp hair and in the toenail, in the schoolboys was 0.4148, and the data were fitted best by the regression equation Y=0.4956X+4.3986, where Y and X are toenail and scalp hair concentration. In schoolgirls the correlation coefficient between the lead level in the scalp hair and in the toenail 0.1159, and the data were fitted best by the regression equation Y=0.0825X+5.9214 here Y and X are toenail and scalp hair concentration. Correlation among lead concentration in the blood, scalp hair and toenail of schoolchildren were statistically significant except between scalp hair and toenail in schoolgirls. These finding suggest that blood, scalp hair and toenail can be used substitutive samples between each others.
Summary
A Study on the Body Fatness and Lifestyles of Some Medical Students.
Dong Kee Ahn, Joong Myung Choi, Tai Young Yoon, Dong Joon Lew, Soon Young Park
Korean J Prev Med. 1995;28(1):85-102.
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AbstractAbstract PDF
This study was carried out to evaluate the associations between lifestyles and Body Mass Index in a group of 349 male and 65 female medical students, ages 17 to 31 years. 20.0% of male students and 3.1% of female student showed the over weight in the classification of obesity by Japan Society for Study of Obesity. There was no statistically significance in the comparison of the height body weight, body mass index, obesity index and body fat(%) according to grade in both sexes. But male students showed increasing tendency of waist-hip ratio with grade. According to obesity category, there was significant difference in the comparison of body weight, body mass index , obesity index, waist-hip ratio and body fat(%), but height. Body mass index was positively related with waist-hip ratio(r=0.6150, p=0.0001) and fat(%)(r=0.5101, p=0.0001) in males and waist-hip ratio (r=0.4734, p=0.001) and fat(%)(r=0.4522, p=0.002)in females. This study provides an opportunity to further examine the relationship of sociodemographic factors and health behaviors to obesity, and suggest the basic concept to match the obesity study to general eqidemiological cohort studies for controlling of chronic adult diseases.
Summary
Health Assessment of Shift Workers in a Automobile Manufacturing Plant.
Jung Jeung Lee, Jong Hak Chung
Korean J Prev Med. 1995;28(1):103-122.
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AbstractAbstract PDF
An investigation on psychophysiological health and social well-being of shift workers been carried out on workers of a automobile manufacturing plant in Ulsan. for 1 month from April, 1993. This cross-sectional survey compared shift workers(n=544) with day workers(n=l15). Each subject completed a questionnaire about his personal habit background. shift schedule. sleep and eating patterns. subjective digestive symptom and psychological well-being and distress using the General Well-Being schedule(GWB) by self administrated questionnaire that was developed for the U. S. Health and Nutrition Examination surveys (HANES I). chi-square analysis was used for discontinuous data and the t-test was used for continous data to determine whether differences noted between the two groups. In terms of sleep quality, a greater percentage of shift workers frequently had trouble getting back to sleep once awakend(p<0.01) and a greater percentage of shift workers awakend tired or sleepy frequently more often than day workers(p<0.05). In rating the quality of their sleep, more shift workers rated their sleep fair to poor than day workers, and greater percentage of shift workers felt tired or sleepy at work two or more times per week(p<0.01) and a much higher percentage of shift workers felt tired or sleepy after work every days(p<0.01). In terms of sleep patterns, a much higher percentage of day workers reported uninterrupted sleep per 24hours than shift workers. The shift workers reported different eating patterns from day workers but there were no statistically significant and rate of their appetite. Thirteen percent of day workers reported the best appetite but only 6.6% of shift workers had the best appetite. The gastric complaints is more frequent in shift workers than day workers(p<0.01). Among subscores in General Well-Being Schedule, anxiety, depression, positive well-being and vitality subscale of shift workers were lower than those of day workers(p<0.05) and general health and self control subscale of shift workers were lower than those of day workers but there were no statistical significant difference. Based on these study result, it could be concluded that the shift work has significant effects on some psychophysiological conditions of the workers.
Summary
Community screening for stress by using General Health Questionnaire.
Soo Sung Oh, Kwang Seub Lee, Seok Joon Sohn, Jin Su Choi, Jung Ae Rhee
Korean J Prev Med. 1995;28(1):123-140.
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AbstractAbstract PDF
This study investigated the stress of community residents in Kwang-Ju and Chonnam areas by using the General Health Questionnaire(GHQ-60) as a instrument of stress measurement. The number of subject were 445 residents who lived in three areas (large city, middle city, and rural area) and they were individually interviewed in March, 1994. The result of study showed that the degrees of stress measured by GHQ-60 were statistically significant in the residents' area, age. sex variables: (a) the residents in middle city among three area had the highest level of stress: (b) the resident who were more than 60 in age had the highest level of stress: (c) the female resident had more stress than male residents: (d) particularly, the residents who were more than 60 years old in the middle city had the highest level of stress. Further, the results of factor analysis showed that there were three factors of social dysfunction, depression and anxiety, and psychosomatic symptom. The social dysfunction factor was statistically significant in both age and resident area variables. The depression and anxiety factor was statistically significant in the residents' area, age. sex variables. The psychosomatic symptom factor was statistically significant in both age and sex variables. The study suggested that they should give a special attention to solve the old people's stress because stress was closely related to residents age.
Summary
Effects of Ethanol on the Activities and Inducibility of Trichloroethylene Metabolic Enzyme System in Rat Liver.
Ki Woong Kim, Seung Kyu Kang, Young Sook Cho, Sei Hui Lee, Young Hahn Moon, Byung Soon Choi, Sang Shin Park
Korean J Prev Med. 1995;28(1):141-152.
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AbstractAbstract PDF
This study was performed to find out the influences of ethanol on the metabolism of trichloroethylene(TRI) in rats. TRI in corn oil at the dosage of 150, 300, 600 mg/kg was injected peritoneally once a day for two days to two groups. In one group ethanol(4 g/kg) was taken orally 30 minutes before TRI injection, and the other group ethanol was not. The results of experiments are as follows: 1. The contents of cytochrome P-450 and b5 had inverse relationship with in-jected TRI amounts in both groups. 2. The activity of NADPH P-450 reductase was decreased slowly in TRI injected group related with TRI amount, but decreased drastically in the group pretreated with ethanol. 3. The activity of NADH b5 reductase had relationship with injected TRI amount, but the statistical significance was found only in the groups of 300 and 600 mg/kg of TRI injected without relevance to ethanol when compared with the group that was not injected. 4. The activity of ADH was more decreased and ALDH activity was more increased in groups that TRI injected and ethanol was pretreated with ethanol groups than in group without any treatment. These results suggest that ethanol may inhibit epoxide formulation, the first step or TRI metabolism, and change from TCE-OH to TCA also.
Summary
Determinant Factors for Expenditure of the Medical Insurance Program for Self-Employeds.
Sin Kam, Jae Yong Park, Min Hae Yeh
Korean J Prev Med. 1995;28(1):153-173.
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AbstractAbstract PDF
This study was conducted to examine the determinant factors for expenditure of the medical insurance program for self-employeds based on the analysis of 1991 "The Medical Insurance program for self-Employeds Statical Yearbook", and also similar yearbooks in the metropolitan and other provinces. The major findings are as follows: We have divided benefits into these four components such as the utilization rate for out-patients. expenses per claim for out-patients as paid by the insurer, utilization rate for in-patients, and the expenses per claim for in-patients as paid by the insurer, in order to examine the determinant factors for it. The results of the study revealed the following findings: in urban areas, the supply of medical care had more influence on the benefits than other demographic and economic variables, while, in county areas, both the supply of medical care and the rate of those aged over 65 affected the provision of benefits. The determinant factors for financial balance of the medical insurance program for self-employeds are: first, the determinant factor for administrative expenses was the number of households. The more the number of household, the less the administrative expenses per the insured. This shows that the economy of scale is being. And so, the administrative district must be taken into consideration in the incorporation of small regional medical societies and should be re-organized for more efficient management. Second. in urban areas. the supply of medical care had more influence on utilization rate and expenses per claim as paid by insurer, and therefore it is necessary to control it. In county areas the supply of medical care and the rate of those aged over 65 raised the utilization rate and expenses per claim as paid by insurer. For the financial stability of county areas. a common fund for medical care for the aged and expansion of finance stabilization fund would be necessary. But, in county areas, it would be unnecessary to control the supply of medical care because it was much more insufficient than in urban areas. The vitalization of public health facilities must be carried out in county areas, for they reduced benefits. Since the more insured in a single household, the less the utilization of the medical insurance program, benefits for habilitation at home should be given consideration. The law of majority and the economy of scale were applied here, and therefore the incorporation of regional medical societies must be taken into consideration. In integrating regional medical societies, it would be absolutely necessary to review the structural differences among all regional medical societies, the medical demand of each region, and also the local characteristics of each region.
Summary
Neurobehavioral Change on the Lead Exposure Workersq.
In Geun Park, Duk Hee Lee, Yong Hwan Lee, Jin Ha Kim, She Han Jang
Korean J Prev Med. 1995;28(1):175-186.
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AbstractAbstract PDF
No abstract available.
Summary
Structural Modeling of Health Concern, Health Practice and Health Status of Koreans.
Soon Young Lee, Myong Sei Sohn, Chung Mo Nam
Korean J Prev Med. 1995;28(1):187-206.
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AbstractAbstract PDF
The purpose of this study was to determine the relationships among the health concern, health practice and health status of Koreans. This study utilized the data from Korean individuals(1,304 male and 1,495 females), whose ages were between 20 and 59. The data were analyzed using SAS version 6.04 and LISREL version 7.13. The analytic methods for the study were chi-square analysis and covariance structural analysis. The results of the study were as follows. (1) There were significant positive relationships between health concern level and health practice index, and between health practice index and self-perceived health status. (2)There were negative relationships between practice index and chronic illness, and between health practice index and acute illness only in female. (3) Based on the findings, the structural model of the health concern, health practice, health status and socioeconomic variables was established and then the covariance structural analysis was used. The higher educational level and economic status were, the higher the health concern was. And urban residents were much more concerned with their health than rural residents. The more persons were concerned with health, the more they did health practices. And the more the health practice was, the higher the health status was. The younger the persons were and the higher the health status of one's family was, the higher the health status was. In female, the higher the economic status was, the higher the health status was.
Summary
Impacts of Implementation of Patient Referral System in terms of Medical Expenditures and Medical Utilization.
Sang Hyuk Jung, Han Joong Kim
Korean J Prev Med. 1995;28(1):207-224.
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AbstractAbstract PDF
A new medical delivery system which regulated outpatient department(OPD) use from tertiary care hospitals was adopted in 1989. Under the new system, patients using tertiary care hospital OPD without referral slip from clinics or hospital could not get any insuranced benefit for the services received from the tertiary care hospital. This study was conducted to evaluate the Patient Referral System(PRS) with respect to health care expenditures and utilization. Two data sets were used in this study. One was monthly data set(from January 1986 to December 1992)from the Annual Report of Korea Medical Insurance Corporation(KMIC). The other was monthly joint data set composed of personal data of which 10% were selected randomly with their utilization data of KMIC from January 1988 to December 1992. The data were analyzed by time-series intervention model of SAS-ETS. The results of this study were as follows: 1. There was no statistically significant changes in per capita expenditures following PRS. 2. Utilization episodes per capita was increased statistically significantly after implementation of PRS. The use of clinics and hospitals increased significantly, whereas in tertiary care hospitals the use decreased significantly immediately after implementation of PRS and increased afterwards. 3. Follow-up visits per episode were decreased statistically significantly after implementation of PRS. The decrease of follow-up visits per episode were remarkable in clinics and hospitals, whereas in tertiary care hospitals it was increased significantly after implementation of PRS. 4. There was no statistically significant changes in prescribing days per episode following PRS. Futhermore, clinics and hospitals showed a statistically significant decrease in prescribing days per episode, whereas in tertiary care hospital it shower statistically significant increase after implementation of PRS. 5. Except high income class, the use of tertiary care hospitals showed statistically significant decrease after implementation of PRS. The degree of decrease in the use of tertiary card hospitals was inversely proportional to income. These results suggest that the PRS policy was not efficient because per capita expenditures did not decrease, and was not effective because utilization episodes per capita, follow-up visits per episode, and prescribing days per episode were not predictable and failed to show proper utilization. It was somewhat positive that utilization episodes per capita were decreased temporarily in tertiary card hospitals. And PRS policy was not appropriate because utilization episodes per capita was different among income groups. In conclusion, the PRS should be revised for initial goal attainment of cost containment and proper health care utilization.
Summary
Hematuria among Benzidine Dye Industry Workers.
Mi A Son, Domyung Paek, Jung Kun Choi, Su Kyeong Park, Jung Soon Park, Se Min Oh, Jung Sun Park, Dong Ook Park
Korean J Prev Med. 1995;28(1):225-243.
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AbstractAbstract PDF
Benzidine Industry in Korea has started after Japan has banned its production in early 1970's. and it has been in operation in Korea for over 20 years. However, it is not known yet whether any bladder cancer has developed from benzidine exposure. This study was done to screen benzidine-exposed workers for bladder cancer, and to examine the feasibility of employing screening test at the workplace. All the workplaces that manufacture or use benzidine for more than 20 years in Korea have been covered in this study, and they include 2 benzidine manufacturing factories, 5 benzidine using factories, as well as 2 benzidine free factories as an outside control. In total, 516 workers were screened with urine stick test and urine cytology test for the evidence of hematuria and abnormal urothelial cells. Each worker was also asked about risk factors and symptoms of bladder cancer including past medical history, smoking, medication and occupational history. Benzidine in the air was measured by personal and area sampling. Out of 516 screened workers, 84(16.3%)workers showed positive hematuria in urine stick test, and 7(1.4%)workers showed degenerative cells in urine cytology tests. Those workers with abnormal urine test results who have been exposed to benzidine for more than 10 years were further screened, and, in total. 23 workers were examined with intra-venous pyelography and cystoscopy. None of those screened had any evidence of bladder cancer. When workers with only past hematuria history were included in the positive hematuria group, 96(18.5%) had positive hematuria. On the multiple logistic regression analysis, positive hematuria was significantly associated with benzidine exposure history of other occupations with elevated bladder cancer risk, pyuria and glycosuria. The association got stronger as direct benzidine exposure was accounted through individual task analysis, and as exposure duration was accounted with tenure analysis. For those with benzidine exposure with more than 10 years of tenure, the odds of having positive hematuria was elevated 2.14(95%C.I is 1.08 to 4.25) times more than for those without exposure. Even though bladder cancer was not detected for several limitations including short observation period, majority of studied workers with short latency, healthy worker effect, and low sensitivity of single screening test in a cross-sectional study, the study results suggest that hematuria screening is a feasible and very useful test for bladder cancer screening among benzidine exposed workers.
Summary

JPMPH : Journal of Preventive Medicine and Public Health