Benzene and toluene, which are widely used aromatic hydrocarbons in workplace, are recently proved to cause health hazards due to their toxic effects. This study investigated the influence of toluene on the urinary excretion of benzene metabolite by administering short term exposure limit(STEL) of these compounds(i.e., 13.8mg/kg of benzene and 108.8mg/kg of toluene) intraperitoneally into Sprague-Dawley rats. After administration, urinary phenol concentration of rat was measured by gas chromatography for every three hours. Data were analyzed by non-parametric statistical methods using Kruskal-Wallis multi-sample test and Mann-Whitney U test. The following results were obtained: 1. Administration of STFL-benzene increased urinary phenol concentration in rats. 2. Urinary phenol concentration was increased logarithmically according to the dosage of benzene. 3. Excretion of phenol in urine was decreased when benzene and toluene were administered simultaneously compared with administering benzene alone. In Summary, these results reveal that administration of STEL of toluene has antagonistic effect of urinary excretion of benzene metabolite in rats.
Animals ; Benzene* ; Chromatography, Gas ; Hydrocarbons, Aromatic ; Metabolism* ; Phenol ; Rats* ; Rats, Sprague-Dawley ; Threshold Limit Values ; Toluene

Chromic acid has widely been used for decorative chromium plating, hard chromium plating, and surface treatment of raw materials. However, its strong oxidizing action has been found to cause corrosion of mucous membranes and skin, such as the nasal septum, conjunctiva, face, and hand skin. Excessive exposure to chmmic acid has frequently caused ulceration and perforation of a nasal septum. These ulcerations are painless and confined to the cartilaginous portion at the lower anterior part of the septum known as Kisselbach's or Little's area. This study was undertaken to investigate the general characteristics, actual conditions of the working environment and the prevalence rate of nasal septal perforation due to inhalation of chromic acid mist in workers employed at plating industries. This study was conducted on 627 workers who were exposed to chromic acid from July to November 1988. The results were summarized as follows: 1. The mean age of workers with septal perforation was 26 years and the mean working duration was 84 months. 2. The prevalence rates of nasal septal perforation and ulceration of mucosa of the plating workers were 31.7% and 10.5% respectively. 3. The significant variables related with occurrence of nasal septal perforation were age of workers, working duration, kinds of plating, efficiency of local ventilation and performance of health examinations. From the above results, occurrences of nasal septal perforation in plating workers were affected by the duration of chromium exposed work and state of the working environment. Prevention of occupationsl diseases fri plating workers will be accomplished by implementation of an industrial health care system which includes thorough health checkups for workers and regular environmental monitoring.
Chromium ; Conjunctiva ; Corrosion ; Environmental Monitoring ; Hand ; Inhalation ; Mucous Membrane ; Nasal Septal Perforation ; Nasal Septum ; Occupational Health ; Prevalence ; Skin ; Ulcer ; Ventilation

OBJECTIVES: In this study, radiotechnologists who work performing PET and PET/CT methodologies were analyzed in order to find the cause for the differences in radiation exposure as they applied to general characteristics, work characteristics, knowledge, and exposure recognition or conduct. METHODS: From April 15th, 2010 to May 14th, 2010, we conducted a retrospective analysis on 80 radiotechnologists using data garnered from their individual general characteristics, work characteristics, knowledge, and exposure recognition or conduct. Their average annual radiation exposure dosages were measured using a thermoluminescence dosimeter. A multiple regression analysis was performed as a statistical tool. RESULTS: Regarding the general PET and PET/CT characteristics, when the work experience was short, the exposure dose was higher. The factors of age, marriage, work experience in nuclear medicine, PET, PET/CT, and sex were found to have statistically significant effects. The knowledge, recognition, and conduct factors for the radiotechnologists were affected by unsecure radiation exposure at the moment of carrying, unsecure radiation exposure at the moment of injection, the application of protection at the moment of injection, and the use of auto distributor. It was found that, the use of an auto distributor, efforts in reducing the radiation exposure, unsecure exposure when with a patient, and the application of protective procedures at the moment of injection affected the overall factor of radiotechnologists radiation exposure dose. CONCLUSIONS: We believe that if radiotechnologists would reduce their radiation exposure by using auto distributors, make efforts to reduce the chance of exposure, and be conscious of radiation, they would be able to reduce the radiation exposure dose even during unavoidable circumstances.
Humans ; Lifting ; Marriage ; Nuclear Medicine ; Retrospective Studies

PURPOSE: Multiple chemical sensitivity (MCS) is a clinical syndrome representing multi-organ and psychological symptoms caused by chronic exposure to various chemicals in low concentrations. We evaluated the prevalence and related factors of MCS targeting Korean adults using the Quick Environmental Exposure and Sensitivity Inventory (QEESI(c)). METHODS: A total of 446 participants were recruited from Severance Hospital. Participants underwent a questionnaire interview including questions on sociodemographic factors, occupational and environmental factors, allergic diseases, and the QEESI(c). Among them, 379 participants completed the questionnaire and the QEESI(c). According to the QEESI(c) interpretation results, participants were divided into very suggestive (VS) group and less suggestive (LS) group. RESULTS: The estimated prevalence of MCS was higher in allergic patients than non-allergic participants (19.7% and 11.3%, respectively, P=0.04). In the multivariate logistic regression analysis, ages of 30-39 (OR, 2.94; 95% CI, 1.25-6.95) and those of 40-49 (OR, 2.51; 95% CI, 1.02-6.21) were significantly related to MCS compared to those aged less than 30 years. Female sex (OR, 2.16; 95% CI, 1.11-4.18), experience of dwelling in a new house (OR, 2.05; 95% CI, 1.04-4.03), and atopic dermatitis (OR, 1.95; 95% CI, 1.04-3.69) were also significantly related to MCS. However, only age of 30-39 in the allergic group was significant in the stratified analysis. CONCLUSIONS: The estimated prevalence of MCS was higher among allergic patients than non-allergic participants. People with experience of dwelling in a new house and atopic dermatitis were more at risk of being intolerant to chemicals. Further studies to provide the nationally representative prevalence data and clarify risk factors and mechanisms of MCS are required.
Adult* ; Dermatitis, Atopic ; Environmental Exposure ; Female ; Humans ; Logistic Models ; Multiple Chemical Sensitivity* ; Prevalence ; Risk Factors

Adenoid cystic carcinoma arises rarely in the nasal cavity and paranasal sinus. Treatment strategy showing the best survival rate includes surgical excision and adjuvant radiotherapy. There were a few case reports of radiation-induced osteosarcoma from adenoid cystic carcinoma overseas but not in Korea. We experienced a case of radiation-induced low-grade osteosarcoma in the middle skull base including sphenoid bone, which had arisen after 10 years of radiotherapy of adenoid cystic carcinoma. Authors present this case with serial imaging findings and literature review.
Carcinoma, Adenoid Cystic* ; Korea ; Nasal Cavity* ; Neoplasms, Radiation-Induced ; Osteosarcoma* ; Radiotherapy* ; Radiotherapy, Adjuvant ; Skull Base* ; Sphenoid Bone ; Survival Rate

After the trauma of frontoethmoidal sinus, post-traumatic mucocele may occur. Surgical removal of the lesions rarely produces cerebrospinal fluid (CSF) leakage and even delayed tension pneumocephalus. We experienced a case of fronto-ethmoid mucocele complicated with peri-operative CSF leakage and post-operative tension pneumocephalus which was improved by conservative treatment. It is imperative to take into account the potential for tension pneumocephalus when a patient suffers from severe headache after sinus surgery.
Cerebrospinal Fluid Leak* ; Cerebrospinal Fluid* ; Ethmoid Sinus ; Frontal Sinus ; Headache ; Humans ; Mucocele ; Pneumocephalus*

BACKGROUND: This study was conducted to evaluate vinly chloride exposure in vinyl chloride and poly vinyl chloride manufacturing factories. The object of this study was compare two different type of air sampling method that of, NIOSH and OSHA recommended and Investigate quantitative correlation between level of vinyl chloride exposure and urinary thiodiglycolic acid excretion. METHODS: Air sampling was conducted by two method and sampling mediums were located at workers breathing zone in the same location. Sampling mediums were changed in 60 minute interval and sampling pumps were recalibrated at the same time. Urine was collected before and end of shift were stored frozen and determined by GC/FID analysis. RESULTS: In NIOSH method, time weighted average was 3.562 +/- 2.898 ppm and OSHA method time weighted average was 4.051 +/- 3.700 ppm. Concentration of urinary TdGA in before shift was 0.527 +/- 0.828 g/g creatinine and end of shift was 4.190 +/- 7.665 mg/g creatinine. Difference of urinary TdGA between end of shift to before shift was 3.662 +/- 7.865 mg/g creatinine. In NIOSH method, correlation coefficient between 8hour-time weighted average (8hrs-TWA) and urinary concentration of TdGA was r=0.666. and last period vinyl chloride level (6th-TWA) and urinary TdGA concentration was r=0.972. In OSHA method, correlation coefficient between last period vinyl chloride level (6th-TWA) and urinary concentration of TdGA was r=0.976 and this was highest value. CONCLUSION: There was no statistically significant difference in NIOSH method and. OSHA method. A correlation were found between level of vinyl chloride exposure and urinary thiodiglycolic acid excretion. Also, vinyl chloride exposure had significantly effected on the urinary thiodiglycolic acid excretion.
Creatinine ; National Institute for Occupational Safety and Health (U.S.) ; Respiration ; United States Occupational Safety and Health Administration ; Vinyl Chloride*

The purpose of this study was to find a better evaluation method by comparison and analysis of the subdivision-score for preventive medicine with other subjects and total score. Among the 475 students who were second grade in 1983, 1984 and 1985, we analyzed the scores for all subjects at Yonsei University College of Medicine obtained by 443 students, with the exception of 32 students who had a temporary absence from school, failed or had been expelled. And we analyzed the score for preventive medicine of 162 students who were second grade in 1987 and 179 students who were second grade in 1988. Statistical analysis of the above was done using the correlation analysis, chi-square test and discriminating index. The results were as follows: 1. The correlations of the subdivision of preventive medicine in 1984, 1987 and 1988 were statistical significantly high(r=0.36-0.56). 2. The grades obtained for preventive medicine and for other subjects except pediatrics (clerkship) were not independent. 3. The discriminating indices that determined whether or not a pertinent evaluation was made were 0.42 in 1983, 0.52 in 1984 and 0.54 n 1985. These results were classified as excellent. These results suggest that the score of a subject is determined not by the characteristics of the subject, but by the amount of personal study.
Humans ; Pediatrics ; Preventive Medicine*

Workplace violence is related to various health effects including mental illness such as anxiety or depression. In this study, the relationship between the experience of workplace violence and depression in substitute drivers in Korea, namely, daeri drivers, was investigated. To assess workplace violence, questions regarding types and frequency of the experience of violence over the past year were asked to the daeri drivers. In order to assess the risk of depression, the Center for Epidemiological Studies Depression Scale was used. Odds ratios with 95% confidence intervals of depression were estimated using multiple logistic regression analysis. All of the daeri drivers had experienced instance of verbal violence while driving and 66 of the drivers (34.1%) had been in such a situation more than once in the past quarter of a year. Sixty-eight daeri drivers (42.2%) had experienced certain type of physical violence over the past year. Compared to daeri drivers who had experienced workplace verbal violence less than 4 times and who had not experienced workplace physical violence over the past year, higher odds ratio was observed in daeri drivers who had experienced workplace verbal violence or physical violence, more than 4 times and more than one time respectively, after adjustment. Experience of verbal or physical type of workplace violence over the past year increased the risk of depression in the daeri drivers. Because violence against drivers can compromise the safety of the driver, the customer, and all the passengers, it is imperative that the safety and health of daeri drivers be highlighted.
Adult ; Aged ; *Automobile Driving/psychology ; Depression/epidemiology/*etiology ; Driving Under the Influence/prevention & control/psychology ; Humans ; Male ; Middle Aged ; Occupational Health ; Odds Ratio ; Republic of Korea/epidemiology ; Surveys and Questionnaires ; *Workplace Violence

The objectives of this study were to develop optimal analytic methods for detecting urinary 2-thiothiazolidine-4-carboxylic acid (TTCA) and thiocarbamide simultaneously and to evaluate the usefulness of these metabolites to a biological exposure index (BEI) for carbon disulfide (CS2) exposure. For this experiment, synthesized TTCA and thiocarbamide were used. The synthesized TTCA was identified by infrared spectrophotometer, nuclear magnetic resonance spectrometer and thin layer chromatography. The recovery rates of both metabolites were calculated to find the optimum analytical method. The amounts of urinary TTCA and thiocarbamide were measured by using an ultraviolet detector connected to high performance liquid chromatography (HPLC) after the administration of CS2 (350, 700 mg/kg) into Sprague-Dawley rats intraperitoneally. The maximum absorbance wave lengths for TTCA and thiocarbamide were 272 and 236 nm, respectively. Ethyl acetate extraction with NaCl as a salting-out reagent was used as a simultaneous extraction method for these metabolites. HPLC conditions for these metabolites included using a NH2 column, 50 mM KH2PO4: acetonitrile (85:15) and pH 3. Excreted amounts of urinary TTCA and thiocarbamide were increased significantly following CS2 administration. TTCA, which was already adopted as a BEI for CS2 by the American Conference of Governmental Industrial Hygienists (ACGIH), seems to be a more useful BEI for CS2 exposure than thiocarbamide. However further studies are needed to increase analytical efficiency before thiocarbamide can be adopted as a BEI and to apply this analytic method for simultaneous analysis of these metabolites in workers exposed to CS2.
Animal ; Carbon Disulfide/pharmacology* ; Environmental Exposure* ; Rats ; Rats, Sprague-Dawley ; Thiazoles/urine* ; Thiourea/urine* ; Urea/urine*