Lessons learned from new emerging infectious disease, Middle East Respiratory Syndrome coronavirus outbreak in Korea / 한국역학회지

No abstract available.

Epidemiologic Transition of Communicable Diseases in Korea: Academia's Contributions to the National Communicable Disease Prevention and Control Programs / 한국역학회지

This paper describes the transition of communicable diseases in Korea since 1970s. Some of Korean's general living background and health indicators are introduced, followed by trends in the changes during the last several decades in socioeconomic, demographic, and living environmental status, which are closely associated with the transition of communicable diseases. The current incidence of classified, notifiable disease, the incidence by year, and the transition of communicable diseases are presented. Governmental responses to prevent and control communicable diseases, including both emerging and re-emerging infectious diseases, which have become recognized as having public health importance are described. Finally, the role played by academia during the last several decades in the successful control of communicable diseases is analyzed.

A study on the change of hepatitis B markers with the passage of time in nonvaccinees-A follow-up data of visitors in a health examination center for three years

BACKGROUND: Korea is an epidemic area of hepatitis B. There are needs for longitudinal study to measure quantity of hepatitis B infection status in Korea. This study was designed to observe natural course of hepatitis B markers in the same person for three years. The objective of this study was to investigate incidence of new infection and persistence of previous infection. METHODS: The study subjects were clients who visited a health examination center in Seoul twice with an interval of three years, from 1995 to 2000. They replied as nonvaccinee on both occasions for hepatitis B by self-administered questionnaire. Hepatits B markers were measured by radioimmunoassay on all visits. There were 103 subjects with 61 men and 42 women. RESULTS: The positive rate of hepatitis B surface antigen was 20.4% initially, which changed to 18.5% after three years. The positive rate of hepatitis B surface antigen was 20.4% initially, that was changed as 18.5% after three years. The positive rate of hepatitis B surface antibody was 61.2% initially, which increased to 66.0% after three years. The positive rates of hepatitis B surface antibody in men were 63.9% initially and 68.9% after three years, which showed statistically significant trend. (P=0.08). The positive rate of hepatitis B core antibody was 89.3%, which remained the same after three years. There was no positive conversion case of hepatitis B surface antigen. The negative conversion rate of hepatitis B surface antigen was 2/63(3.2%). The positive conversion rate of hepatitis B surface antibody was 7/40(17.5%), and negative conversion rate of that was 2/63(3.2%). The positive conversion rate of hepatitis B core antibody was 3/11(27.3%), and negative conversion rate of that was 3/92(3.3%). CONCLUSION: Hepatitis B markers changed in the direction of increase of infection incidence, rather than natural disappearance of markers in nonvaccinees. The mechanism was postulated as occurrence of new infection mainly, but the possibility of double infection by variants of hepatitis B virus could not be ruled out. We confirmed that positive rate of hepatitis B marker in males was not only higher cross-sectionally, but also increased higher longitudinally. We suggest a follow-up study of hepatits B markers to be performed because hepatits B markers showed dynamic changes. We think the high risk groups of hepatitis B infection have a priority in follow-up study.

Bioterrorism and the Role of Physicians

No abstract available.

The Role of Epidemiology against Emerging and Reemerging Diseases / 한국역학회지

PURPOSE: Due to remarkable developments in technology and great efforts made by Health Organizations, most of infectious diseases had been under control. However, ecological changes and biological variations resulted in emerging and re-emerging infectious diseases, which threaten the global health and may have the possibility of being abused as biological weapon. Therefore it is indispensable to understand the latest information and knowledge in order to cope with the emergency situation. RESULTS: In Korea, several reemerging diseases such as Malaria, Hepatitis A, Shigellosis, Mumps, and food poisoning has been increasing conspicuously since 1990. Also Diphtheria, plague, yellow fever and dengue fever have been potential threats, considering substantial international trades. CONCLUSION: There have many newly emerged and re-emerged infectious diseases identified in recent few decades in Korea. Thus as epidemiologic professionals, we have to get ready, particularly following missions to be carried out : 1) to keep eyes open to look for emerging and reemerging diseases continuously and keep up the latest global information, 2) establish the co-operational organizations to prepare immediate action against the sudden outbreak, 3) publicize, educate, establish and perform the missions, taking initiative in training clinicians, 4) upgrade professional competency by familiarizing ourselves with epidemiologic investigations, and 5) fulfill the responsibilities as health keepers of the nation.

A Study on the Correlation between Categorization of the Individual Exposure Levels to Agent Orange and Serum Dioxin Levels Among the Korean Vietnam Veterans / 예방의학회지

OBJECTIVES: In an epidemiologic study on the health impact of Agent Orange exposure, the valid estimation of exposure level is the most important step. Based on recent studies, we examined the correlation between exposure levels categorized by personal exposure estimates and serum 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD, Dioxin), exploring the possibility of utilizing the exposure level as a surrogate for the estimate of exposure to agent orange. METHODS: During the study period (Jan 1996-Feb 1996), blood specimens of 745 subjects taken randomly among 1,329 persons and kept frozen, were analyzed for 2,3,7,8-TCDD and six other dioxin congeners. The serum dioxin and congeners were measured in 1998 by CDC ,adjusted for serum lipids. We categorized the total exposure scores into five groups based on Agent Orange exposure data collected by interview and military records. Pearson and Spearman's correlation coefficients & multiple regression analysis were used to identify the relationship of the exposure level categorized with serum concentration of 2,3,7,8-TCDD, and six other dioxin congeners. RESULTS: Dioxin and the other congeners, except 1,2,4,6,7,8-HpCDD, showed significant correlations to exposure categories (p<0.005); 2,3,7,8-TCDD and OCDD showed positive correlations, whereas the other congeners did negative. The values of 2,3,7,8-TCDD differed according to exposure category and proportionally increased from the low exposure group to the high, a dose-response relationship, even after other possible confounding variables were adjusted for. In multiple regression analysis, age(beta=0.033), dioxin(beta=0.433), 1,2,3,7,8-PeCDD(beta=0.998), 1,2,3,4,7,8-HxCDD(beta=0.773), 1,2,3,6,7,8-HxCDD(beta=0.255), 1,2,3,7,8,9-HxCDD(beta=3.468), 1,2,3,4,6,7,8-HpCDD(beta=0.109) were found to be significantly related to the total exposure score(p<0.005). CONCLUSION: This study demonstrated that the use of such categorizations as a surrogate measure of agent orange exposure in identifying exposure degrees in a health impact study is valid.

A Study on the Validity of the Hospital Infection Surveillance Records Collected by Ward Liaison Nurses / 감염

BACKGROUND: Hospital infection surveillance is a dynamic process for gathering, managing, analyzing, reporting and re-evaluating the data. Recently there has been an increased awareness of the importance of hospital infection surveillance and management program in Korea. The most ideal way among the hospital infection surveillance systems is known to be the "reference method". In this method all hospital patient records and charts are reviewed and the infected patient are investigated in daily basis. However it requires enormous efforts to apply this method in hospitals with limited personnel resources. Although the number of the hospital having full-time hospital infection control nurses has been increased considerably in Korea the effective hospital control programs have not been established yet in most hospitals owing to the lack of full-time hospital infection control nurses. Nevertheless it became indispensable to develop an alternative hospital infection surveillance program that is readily available. This study was carried out to investigate epidemiologic characteristics, and assess the efficiency and validity of ward liaison surveillance method for nosocomial infection surveillance in a general hospital without full-time infection control nurses. METHOD: During the period of the study, from March 1 to March 31, 2000, cases of hospital infection collected by two different methods, reference method and ward liaison nurse surveillance, were compared. The validity of ward liaison surveillance data was examined using the data collected by the reference method as gold standard. RESULT: In the data collected by the reference method, 94 cases of hospital infection were identified whereas 83 cases by the ward liaison nurses. The incidence rate of hospital infection was 9.5% during one month; the incidence rates were higher in males (12.6%) than female (6.7%) and in age group of 50s. The incidence rates by ward were 38.8% in intensive care unit, 45.5% in neurosurgery, 18.6% in neurology ward, 12.8% in internal medicine, 10.6% in orthopedic ward, and 8.6% in general surgery. Sites of hospital infection in the order of decreasing frequency were urinary tract (24.8/1000 discharge patients), lung (22.2), wound (18.2), and other respiratory systems (15.2). The type of microorganisms isolated were 16: three gram-positive bacteria, eleven gram-negatives and two fungi. Staphylococcus was the most frequently isolated organism, 21 strains, among which 17 strains were methicillin-resistant Staphylococcus aureus (only one strain was sensitive to methicillin) and three strains were methicillin resistant Staphylococcus epidermidis. Seventeen strains of Pseudomonas aeruginosa were isolated from pneumonia, urinary tract, and wound. Escherichia. coli, Serratia marcencecs, Acinetobacter baumannii, Klebsiella pneumoniae, Enterococcus faecalis, E. faecium, Enterobacter cloacae, Streptococcus pneumoniae, and Candida albicans were also isolated. There were twenty-two specimens that revealed no growth of any organisms. In the ward liaison nurse surveillance method, the number of false positive hospital infection was eleven cases and the false negative was 22 cases. The validity evaluated by four different measurements were sensitivity 76,7%, specificity 98.7%, positive predicted value 86.7%, negative predicted value 97.5%. Thus the ward liaison nurse surveillance method was shown to be a valid method with high efficiency. The false positive and false negative cases were mainly occurred by the deficient knowledge in the definition of hospital infection, and deficient skills of investigating the patient's symptoms and clinical course; the liaison nurses had not checked all the surgical site resulting in low sensitivity in surgical site infection. CONCLUSION: According to the results, the epidemiologic characteristic of hospital infection in this particular community hospital studied was not much different from other study results; the incidence rate of hospital infection for one month was 9.5%. On the other hand the ward liaison nurse surveillance method was shown to be satisfactory in detecting hospital infection. This could be a useful method for hospitals without full-time infection control nurses. Furthermore, the validity of this method could be improved by accumulation of the knowledge and skills on hospital infection surveillance through a well planned on-the-job training program for the nurses.

Evaluation of the Completeness of Case Reporting during the 1998 Cheju-do Mumps Epidemic, Using Capture-recapture Methods / 예방의학회지

OBJECTIVES: To estimate mumps incidence during the study period and to evaluate the completeness of case reporting. METHODS: Capture-recapture methods, originally developed for counting wildlife animals, were used. The data sources were 1) the National Notifiable Communicable Disease Reporting System (NNCDRS; 848 cases), 2) the School Health Reporting System, temporarily administered by the Division of Education (SHRS; 1,026 cases), and 3) a survey of students (785 cases). We estimated the number of unobserved mumps cases by matching the three data sources and fitting loglinear models to the data. We then determined the estimated total number of mumps cases by adding this to the number of observed cases. Completeness was defined as the proportion of observed cases from each source to the total of estimated cases. RESULTS: The total number of observed cases was 1,844 and the total number of estimated cases was 1,935 (95% CI: 1,878-2,070). The overall completeness was 43.8% of the NNCDRS, 53.0% of the SHRS, and 40.6% of the survey. However, completeness varied by area and age. CONCLUSION: Although the completeness of NNCDRS data appeared higher than in the past, it is difficult to generalize this result. In Korea, it is possible to estimate the size of health hazards relatively cheaply and quickly, by applying capture-recapture methods to various data using a multiple data collection system.

A comparative study on mortality patterns among Koreans, Korean-Chinese and Chinese

In order to understand the causal mechanism of disease aggregates peculiar to place and ethnicity, mortality data of Yanji city, China (1993) were collected, examined for validity and analyzed. Age standardized, age specific mortality rates and ten leading causes of death were compared with 1993 Korean mortality statistics. Age standardized mortality rates for both sexes were highest in Korean-Chinese followed by Koreans and Chinese (the lowest). Out of ten leading causes of death (54%-70% of the total deaths), seven for male and six causes of death for female were common in all groups. Korean-Chinese females had more similar patterns to Chinese females than males did. Differences in mortality rates by causes of death among groups suggested that hypertensive diseases and respiratory tuberculosis were associated with ethnicity, homicide/injuries inflicted by others, diabetes mellitus and chronic renal disease with environment, and others with both ethnicity and environment. These results suggest that a few causes of death were attributed to either ethnicity or environment whereas most of the ten leading causes of deaths were attributed to mixed impacts of both ethnicity and environment.

Nationwide Telephone Survey on Leisure Time Physical Activity among Koreans / 한국역학회지

Epidemiologic research has demonstrated that varying grade of physical activity has protective effects on several chronic diseases, including coronary heart disease, hypertension, diabetes mellitus, osteporosis, anxiety and depression. Despite the importance of physical activity as an health promotion factor, there have been only a few research data available in Korea. This telephone interview survey on randomly sampled 1,060 adultsaged 15-69 years was carried out to find out the prevalence of self-reported leisure-time physical activity among Korean adults in terms of health promotion practice. The nationwide telephone interview survey was conducted from April through May 1997. Multistage stratified random sampling method was used for sample selection, the respondent was randomly selected from an entire group of adults who lived at the residence connected with the telephone number. A total of 1,060 adults were interviewed and the interviewees' leisure-time physical activity was categorized into four patterns: 'physically inactive', 'irregularly active', 'regularly active, not intensive', and 'regularly active, intensive'. About 53% of the respondents were physically inactive, 15% irregularly active, 14% regularly active, and only 18% were regularly active, intensive. Women were less active than men anc persons of lower socioeconomic status(SES) were less active than higher SES. Physical activity was not significantly associated with smoking status, drinking pattern and overweight, but negatively associated with daily smoking amount and total duration of smoking in smokers. Individuals with higher lever of physical activity were more likely to check blood pressure regularly and have had screening examination for stomach cancer. Conclusively, the proportion of Korean people who perform appropriate level of physical activity in terms of health promotion is still very low, thus an enforced intervention program becomes indispensable to achieve the national health goal by the year 2000.

A study on epidemiologic characteristics and factors associated with excess hospitalization of the patients injured by traffic accident / 한국역학회지

The occurrence of injuries and death caused by traffic accidents have been increasing during last few decades in Korea, which resulted in enormous personal, social and economic loss in terms of death, disability, labour days and medical costs incurred for treatment. Generally, it is well known and even became an hot sociopolitical issue that the duration of hospital stay for traffic accident patients are much longer than that of other patients with the similar condition. The objective of the study is to find out epidemiologic characreristics and management pattern of traffic accident patients in a general hospital of medium-sized, industrialized town. This study was carried out on 177 cases injured by motor vehicle accidents, who were admitted and treated in a general hospital from Feb. 1, 1997 to Sept. 30, 1997. The results obtained are as followings: The most of the patients(44%) were 20-30 years old age group although the occurrence of injuries was more frequent among older ages, 50's for male and 60's for female being 2.1 times more frequent among male. The traffic accidents occurred most frequently(14.1%) in the morning(06:00-08:00) and afternoon(14:00-16:00), and on Saturdays(20.3%); the (14.1% traffic accidents were frequent during weekends for passengers whereas it was more frequent during weekdays for pedestrian. Old and child pedestrians were most vulnerable subjects to traffic accidents. The most common site injured was head(19.9%) and the injury types were fracture of lower extremity(9.3%), skull fracture(8.6%) and rib fracture(8.6%) for both sexes; rib fractures/thoracic spine fractures(12.0%) for female and tibia/ fibula fractures(11.6%) for male. Mean days of hospital stay presumptively judged by the doctor who examined, made diagnosis and admitted the patient was 43.8 days compare to 38.4 days of actual mean days of hospitalixation. On the other hand, the optimal mean days of hospital stay for the patients determined by two doctors independently was estimated to be 26.6 days. Thus the difference between actual days of hospitalization and optimal days of hospitalization was 11.7 days, which can be regarded as excess hospitalization days. It consists 30.5% of actual hospitalization days, an enormous waste of resources. The only factor associated with this excess hospitalization was payment responsibility for the hospital cost; when the hospitalization expenses are to be paid by the person inflicted the injury there were always excess days of hospitalization regardless of insurance status.

A literature Review Study on Kawasaki Disease with Special Concern on Causal Hypothesis / 한국역학회지

Kawasaki disease that had been identified and reported as a new syndrome complex by a Japanese pediatrician Kawasaki in 1967 still remains as a disease of unknown etiology despite the enormous research efforts throughout the world. We conducted this literature review study with an attempt to formulate causal gypothesis on Kawasaki disease based on research findings published. Summarizing the research results in terms of clinical, pathologic and epidemiologic characteristics we could characterize the causative agent as followings: (1) The agent should have high infectivity and low pathogenicity causing generalized infection, perhaps with more frequent inapparent infection than apparent infection, particularly among immunocompromized, feeble children by preceded infection, (2) The target organ of the agent seems to be endothelial cells of arteries, (3) The agent appears to take airborne transmission route in very special environment where the agent can be supplied by reservoirs other than human beings, and (4) the agent should be quite ubiquitous around human living environment resulting in high herd immunity among adult population. For the time being we propose Coxiella burneti as a possible causative agent that could satisfy the most of the above characteristics.

Serological Immunity to Diphtheria among Korean Population / 감염

BACKGROUND: Diphtheria epidemics in Russia have spread to all the other independent states of the former Soviet Union and East European countries around 1990s. One of the most important measures in preventing diphtheria is to maintain high levels of immunity in the population. We studied the diphtheria antibody levels of 1,086 participants to investigate herd immunity in Korea. METHODS: The tested 1,086 serum specimens were collected from healthy individuals from September 1995 to March 1996. Diphtheria antitoxin titers were measured by a micro cell culture method using Vero cells. Antibody titer of 0.01 IU/ml to neutralize diphtheria toxin is an internationally accepted protective level. RESULTS: We studied the diphtheria antitoxin titer levels of 1,086 cases consisting of 579 males and 507 females. The proportion of protective antitoxin level to diphtheria is 69.2%. Diphtheria antitoxin levels showed no significant difference between males and females. The highest seropositive rate was observed in the 5 to 9-year old age group(95.8%). The seropositivity rate declined with age. The lowest seropositive rate was observed in the 20~39 years of age, maximally 43.4 %. Over 40 years of age, the seropositive rates increased again. CONCLUSION: The antibody titers in the Korean population declined from 95.8% to below 50% with age in the 1~39 year-old age group. To maintain the rate of population with protective antibodies to diphtheria, we recommend Td booster immunization to adults with low antitoxin titers and continuous survey for antitoxin titers.

The Relationship Between Cholesterol Level and Mortality in Korean Women / 한국역학회지

BACKGROUND: There were many efforts to evaluate the relationship between cholesterol and mortality. But almost all of them have been performed on male western people who have higher mean cholesterol concentration than oriental people and have different disease pattern from women's. So, upto now, the relationship of cholesterol to mortality in women with low cholesterol concentration was not well known. We carried out this study to investigate the relationship in Korea women whose mean cholesterol level was lower than that of western people and men. METHOD: Study subjects included in were 100,363 Korean women aged 30-65 years. They undertook multiphasic health examination provided by Korea Medical Insurance Corporation between March 1990 and July 1990, and had no history of cancer and no significant medical illnesses which could change blood cholesterol level. Study subjects were followed for 5.5 years until December 1995 and it was determined whether each subject was dead or alive using the mortality data from the Korea National Statistical office and the Korea Medical Insurance Corporation. Nonlinear ralationship between serum total cholesterol and mortality was investigated with the use of quadratic regression and with dummy variables using the 158-180mg/dl group as the comparison group. To analyzing the relationship between cholesterol concentra-tion and mortality with controlling for age, smoking, alcohol drinking, exercise, diastolic blood pressure, body mass index, pay level, Cox propor-tional hazard model was used. RESULT: During the follow-up period, there were 369 deaths. Mean cholesterol concentration of study subjects was 182.8mg/dl There was no significant association between serum cholesterol and total mortality, but women with cholesterol concentrations below 130mg/dl showed slightly increased risk of death(RR=1.20). Cholesterol had an inverse relationship with mortality from stroke, and women with cholesterol concentrations below 130mg/dl had higher risk of death from stroke(RR=3.28). Although there was no statistical significance,risk of mortality from hemorrhagic stroke in women with very low cholesterol concentration was markedly higher than in women with cholesterol concentrations above 130mg/dl. Mortality relationship with cholesterol. And women with cholesterol concentrations higher than 203mg/dl had abruply increased risk for death from ischemic heart disease. CONCLUSION: Through this study, we could observe an inverse J shaped relationship between cholesterol concentration and mortality in Korean women. The increased risk of mortality from hemorrhagic stroke in people with very low cholesterol concentration supports the previous report which proposed low cholesterol level as a significant risk factor of hemorrhagic stroke. In spite of the lack of statistical signi-ficance, greately increased risk of mortality from ischemic heart disease in people with cholesterol higher than 203mg/dl suggests that cholesterol concentration at the upper end of distribution can be a significant risk factor of ischemic heart disease in women.

Emerging and Re-emerging Infectious Diseases in Korea / 한국역학회지

No abstract available.

Reclassification of Reportable Disease in Korea

No abstract available.

Prevalence and Epidemiologic Characteristics of Hypertension in a Rural Adult Population / 한국역학회지

To determine the prevalence and risk factors of hypertension we performed cross-sectional study in a rural area. We measured BP and body mass index(BMI), and interviewed adult residents over 30-year-old age. 337 males and 357 females participated the survey. BP was checked twice and the mean was used to determine age and sex specific mean BP and prevalence of hypertension. Prevalence of definite hypertension(BP>or=160/95 or on medication) was 14. 0% in males and 17. 7% in females. Risk factor for hypertension was analysed by multiple logistic regression; age (10years: OR=l. 7) and BMI(1 BMI unit: OR=l. 2) were positively associated with hypertension but smoking(1 pack year: OR=0.9) was shown to have inverse relationship.

The Estimation of Prevalence of Diabetes Mellitus in a Rural Adult Population / 예방의학회지

The objectives of this study are to estimate the prevalence of diabetes mellitus(DM) and to identify risk factors associated with fasting blood sugar in a rural adult population. We carried out a cross-sectional study on the residents over 30-year old. Among the 1077 eligible subjects, 725 persons responded to the study; the study consisted of interview on family and past history of DM, anthropometry, blood pressure, and blood sugar level in each subjects. Only 707 subjects of 725 participants had fasting blood sugar(FBS) examined and the rest, 18 subjects were had casual blood sugar examined due to failure of fasting over 8-hour. When subjects had FBS >or= 140mg/dl, 2 hours postprandial blood sugar level was checked after 75g oral glucose loading. The prevalence of DM was 8.9%, and age standardized prevalence rate adjusted to Korean population of 1995 was 5.8%. Mean and SD of fasting blood sugar in men was 99.8 +/- 22.6, and in women was 111.5 +/- 29.9. Mean levels of fasting blood sugar were significantly higher in women than in man and as their ages advanced the prevalencies in creased in both sexes. PP2 blood sugar levels were significantly higher in elder age and in persons with higher FBS levels than others. The risk factors associated with FBS were past history of diabetes, sex, socioeconomic status and waist-to-hip circumference ratio; the risk of diabetes was increased in female, people with past DM history, central obesity and low socioeconomic state. The low socioeconomic status associated with DM in this study, which is different from other study results, should be pursued in further studies.

A study on lead exposure indices of male workers exposed to lead less than 1 year in storage battery industries / 예방의학회지

This study intended to obtain an useful information for health management of lead exposed measuring the lead exposure indices and workers and determine biological monitoring interval in early period of exposure by work duration in all male workers (n=433 persons) exposed less than 1 year in 6 storage battery industries and in 49 males who are not exposed to lead as control. The examined variables were blood lead concentration(PBB), Zinc-protoporphyrin concentration(ZPP), Hemoglobin(HB) and personal history; also measured lead concentration in air(PBA) in the workplace. According to the geometric mean of lead concentration in the air, the factories were grouped into three categories: A; When it is below 0.05mg/m3, B; When it is between 0.05 and 0.10mg/m3, and C; When it is above 0.10mg/m3. The results obtained were as follows: 1. The means of blood lead concentration(PBB), ZPP concentration and hemoglobin(HB) in all male workers exposed to lead less than 1 year in storage battery industries were 29.5+/-12.4 microgram/100ml, 52.9+/-30.0 microgram/100ml and 15.2+/-1.1 gm/100ml. 2. The means of blood lead concentration(PBB), ZPP concentration and hemoglobin(HB) in control group were 5.8+/-1.6 microgram/100ml, 30.8+/-12.7 microgram/100ml and 15.7+/-1.6 microgram/100ml, being much lower than that of study group exposed to lead. 3. The means of blood lead concentration and Zpp concentration among group A were 21.9+/-7.6 microgram/100ml, 41.4+/-12.6 microgram/100ml; those of group B were 29.8+/-11.6 microgram/100ml, 52.6+/-27.9 microgram/100ml; those of group C were 37.2+/-13.5 microgram/100ml, 66.3+/-40.7 microgram/100ml. Significant differences were found among three factory group(P<0.01) that was classified by the geometric mean of lead concentration in the air, group A being the lowest. 4. The mean of blood lead concentration of workers who have different work duration(month) was as follows; when the work duration was 1-2 month, it was 24.1+/-12.4 microgram/100ml,; When the work duration was 3-4 month, it was 29.2+/-13.4 microgram/100ml; and it was 28.9+/-34.5 microgram/100ml for the workers who had longer work duration than other. Significant differences were found among work duration group(P<0.05). 5. The mean of ZPP concentration of workers who have different work duration(month) was as follows; When the work duration was 1 2 month, it was 40.6 18.0 g/100ml, When the work duration was 3-4 month, it was 53.4+/-38.4 microgram/100ml; and it was 51.5+/-60.4 microgram/100ml for the workers who had longer work duration than other. Significant differences were found among work duration group(P<0.05). 6. Among total workers(433 person), 18.2% had PBB concentration higher than 40 microgram/100ml and 7.1% had ZPP concentration higher than 100 microgram/100ml; In workers of factory group A, those were 0.9% and 0.0%; In workers of factory group B, those were 17.1% and 6.9%; In workers of factory group C, those were 39.4% and 15.4%. 7. The proportions of total workers(433 person) with blood lead concentration lower than 25 microgram/100ml and ZPP concentration lower than 50 microgram/100ml were 39.7% and 61.9%, respectively; In workers of factory group A, those were 65.5% and 82.3%; In workers of factory group B, those were 36.1% and 60.2%; In workers of factory group C, those were 19.2% and 43.3%. 8. Blood lead concentration (r=0.177, P<0.01), ZPP concentration (r=0.135, P<0.01), log ZPP (r=0.170, P<0.01) and hemoglobin (r=0.096, P<0.05) showed statistically significant correlation with work duration (month). ZPP concentration (r=0.612, P<0.01) and log ZPP(r=0.614, P<0.01) showed statistically significant correlation with blood lead concentration. 9. The slopes of simple linear regression between work duration(month, independent variable) and blood lead concentration(dependent variable) in workplace with low air concentration of lead was less steeper than that of poor working condition with high geometric mean air concentration of lead. The study result indicates that new employees should be provided with biological monitoring including blood lead concentration test and education about personal hygiene and work place management within 3~4 month.

A study on renal function indices in lead exposed male workers / 예방의학회지

The influence of lead exposure on renal function was studied. Eighty nine lead exposed workers who worked in 2 storage battery factories, and seventy one control workers were chosen for this study. Blood lead(pbB) and zinc protoporphyrin in whole blood(ZPP) were selected as indicators of lead exposure. As indicators of renal function, urinary N-acetyl-beta-D-glucosaminidase(NAG), blood urea nitrogen(BUN), serum creatinine(S-Cr), total protein in urine(U-Tp),and serum uric acid(S-Ua) were selected. The results obtained were as follows: 1. while the mean values of lead exposure indicators of lead workers were significantly different from non-exposed ones, the mean values of NAG, U-TP, BUN and S-Cr of renal function indicators of exposed were also significantly different from non-exposed but their mean values were all within normal limits. 2. BUN, logarithmic U-TP, logarithmic NAG and S-Cr showed statistically significant correlation with pbB. 3. The proportion of workers whose values of renal function indicators were over the normal limits(NAG7.5 U/g cr; U-TP 10.9mg/dl; BuN20 mg/dl; S-Cr1.2 mg/dl; S-Ua7.0 mg/dl) by the level of lead absorption in terms of pbB and ZPP were calculated. The proportion of workers with over the normal limits of U-TP among total workers showed the dose-response relationship. when age is adjusted, U-TP showed significantly strong dose-response relationship with the level of pbB and ZPP.