bluuebunny/crossref_metadata_2025 huggingface dataset:
Therapeutic Efficacy of a Few Diesters of Meso 2,3‐Dimercaptosuccinic Acid during Sub‐Chronic Arsenic Intoxication in Rats
Authors: Flora S.J.S. , Pant B.P. , Tripathi Neelima , Kannan G.M. , Jaiswal D.K.
Published: February 2008

Therapeutic Efficacy of a Few Diesters of Meso 2,3‐Dimercaptosuccinic Acid during Sub‐Chronic Arsenic Intoxication in Rats: S.J.S. Flora, et al. Division of Pharmacology and Toxicology, Defence Research and Development Establishment—The therapeutic efficacy of four diesters derivatives of meso 2,3‐dimercaptosuccinic acid (DMSA) was investigated in subchronic arsenic intoxication in rats. Dimethyl DMSA (DMDMSA), diethyl DMSA (DEDMSA), diisopropyl DMSA (DiPDMSA) and diisoamyl DMSA (DiADMSA) were the diesters of DMSA with methyl, ethyl, isopropyl and isoamyl alcohols and were administered for two 5 day courses of treatment in male rats pre‐exposed to 100 ppm arsenic (III) for 8 weeks. The results show that treatment with these diesters was effective in decreasing blood and soft tissue arsenic contents but was only moderately effective in recovering biochemical indicators. The results suggest that these diesters could be effective arsenic chelators but may be inferior to DMSA in recovering biochemical/clinical indicators following sub‐chronic arsenic exposure.
Relations between Exposure to o‐Dichlorobenzene and Concentrations of Urinary Metabolites
Authors: Kumagai Shinji , Matsunaga Ichiro
Published: February 2008

Relations between Exposure to o‐Dichlorobenzene and Concentrations of Urinary Metabolites: Shinji Kumagai, et at. Department of Occupational Health, Osaka Prefectural Institute of Public Health—The present study aimed to examine the relation between exposure to airborne o‐dichlorobenzene (o‐DCB) and concentrations of four urinary metabolites, i.e., 3,4‐dichlorocatechol (3,4‐DCC), 4,5‐dichlorocatechol (4,5‐DCC), 2,3‐dichlorophenol (2,3‐DCP) and 3,4‐dichlorophenol (3,4‐DCP). Subjects were ten male workers exposed to o‐DCB in synthesizing intermediate products for dyes. Individual exposure to o‐DCB was monitored with a passive dosimeter. Urine samples were collected during the workshift and at the end of the workshift. The concentrations of urinary 3,4‐DCC, 4,5‐DCC, 2,3‐DCP and 3,4‐DCP were determined with a high performance liquid chromatograph. The mean recovery rates for urinary metabolites obtained by our analytical method were 93.2 to 102% with coefficients of variance of 2.7 to 7.5%. The concentrations of 3,4‐DCC, 4,5‐DCC, 2.3‐DCP and 3,4‐DCP in urine collected at the end of the workshift and those during the last four hours of the workshift were shown to be well correlated to the 8‐hr time weighted average (8‐hr TWA) value for the exposure concentration of o‐DCB. The mean ratios (as moles) of 3.4‐DCC to 4,5‐DCC, that of 2,3‐DCP and that of 3,4‐DCP at the end of the workshift were 0.78, 0.42 and 0.37, respectively. The time series of the concentrations of the four metabolites showed that these concentrations varied with time in a similar pattern.
Benzene‐Associated Leukemia and its Risk Assessment
Authors: Kaneko Takashi , Wang Pei‐Yu , Sato Akio
Published: February 2008

Benzene‐Associated Leukemia and its Risk Assessment: Takashi Kaneko, et al. Department of Environmental Health, Medical University of Yamanashi—There is sufficient epidemiological evidence indicating that benzene is a human carcinogen. Although some reports suggest an association of benzene with multiple myeloma, malignant lymphoma and lymphatic leukemia, the closest association is found with the development of acute myeloleukemia. In contrast to epidemiological findings, benzene has induced a variety of tumors in tissues other than bone marrow in experimental animals. Attempts to induce acute myeloleukemia in rodents by benzene have not been fully successful until recently. While relatively low doses of benzene have been confirmed to induce chromosomal aberrations, sister chromatid exchanges and micronuclei in rats and mice, it has not been proven that similar changes occur in humans. For evaluation of the dose‐response relation of benzene‐induced leukemia, the epidemiological studies with a Pliofilm (rubber hydrochloride) cohort are considered most reliable and useful. According to recent re‐examinations of the Pliofilm cohort, it is highly possible that the past epidemiological studies with this cohort under‐estimated the benzene exposure level, and thus over‐estimated the risk of benzene toward leukemia. Many extrapolation models including a linear model, a linearized multistage model, a conditioned log‐logistic model, a quadratic model and a proportional hazards model have been used in the calculation of benzene risk. The risk values calculated so far with the Pliofilm cohort greatly differ according to the extrapolation models employed, and thus it cannot be determined which model is superior. While benzene exposure in the workplace is decreasing, petroleum containing a few percent of benzene has become an important source of benzene exposure for both industrial workers and the general population. Some reports suggest a positive association between gasoline exposure and the development of acute myeloleukemia.
Estimates of Occupational Cancer in Korea
Authors: Cho Soo‐Hun , Kang Daehee , Ko Kyung‐Sim , Kwon Ho‐Jang , Kim Dong‐Hyun , Ha Mina , Han Sang‐Hwan , Ju Yeong Su
Published: February 2008

Estimates of Occupational Cancer in Korea: Soo‐Hun Cho, et al. Department of Preventive Medicine, Seoul National University College of Medicine—An accurate estimation of the contribution of occupational exposure to cancer is very difficult. In order to evaluate the magnitude of the problem of occupational cancer in Korea, the numbers of these cancers were estimated. A panel of physicians was asked to complete a questionnaire survey asking about potentially important occupational cancers. The numbers of occupation‐related cancers in Korea were estimated, based on the numbers of employees exposed to selected occupational carcinogens, the relative risks of affected cancers among exposed employees, and the incidence of those cancers among the general population. More than 90% of physicians who participated in the survey indicated their belief that many occupational cancers have occurred previously without being detected. Preventive medicine specialists reported a greater contribution (5‐30%) than clinical oncologists and cancer surgeons (1‐10%) of occupational exposure to cancer. Participant physicians indicated that lung, bladder, hematopoietic and skin cancer will in the future be major occupational cancers in Korea. The reported chemicals and industries in which occupational cancer will be important included asbestos, petrochemicals, benzene, dyes, radiation, coke oven emissions, polycyclic aromatic hydrocarbons, plating work, and chrome. The estimated annual total of occupational cancer cases in Korea was 5‐28 after subtracting the number of cases in the general population from the number among employees exposed to occupational carcinogens. Although this study has several limitations, it was the first attempt to estimate the number of cases of occupational cancer in Korea. Future studies to accurately estimate the number of employees exposed to occupational carcinogens and to link the existing database on cancer occurrence (e.g. cancer registry, medical insurance data, etc.) with exposure data are needed.
Psychometric Properties of Stress Check List for Self and its Relationship to Health Satisfaction and Psychological Traits (Extroversion‐Introversion)
Authors: Kawada Tomoyuki , Kato Keiko , Iijima Toshihide
Published: February 2008

Psychometric Properties of Stress Check List for Self and its Relationship to Health Satisfaction and Psychological Traits (Extro‐version‐Introversion): Tomoyuki Kawada, et al. Department of Public Health, Gunma University School of Medicine—This study focused on the reliability and validity of the Stress Check List for Self (SCL‐S). Relationships of the SCL‐S to types of work, health satisfaction, psychological traits, current medication, and stress coping were also tentatively analyzed. A self‐administered questionnaire was distributed to employees of a railroad company, of whom 1,706 men aged 18 to 55 were selected randomly and 1,045 (61.3%) responded. The SCL‐S consists of 30 items, each of which is scored 1 or 0, depending on whether or not a symptom is present. The SCL‐S score is defined as the summation of each binary datum. Health satisfaction is scored as 1 (satisfied), 2 (moderately satisfied), or 3 (not satisfied). The psychological trait item is scored as 1 (extrovert) or 2 (introvert). Present medication is scored as 1 (yes) or 0 (no). We also asked the respondents whether they had experienced stress coping, hobbies and consultation with others. Each of these items was scored as 1 (yes) or 0 (no). There was a difference in the mean SCL‐S value among age‐groups as a whole (p < 0.05). Cronbach's alpha coefficient for the target group was 0.817. Principal factor analysis was conducted on 30 items of the SCL‐S. Three factors were extracted. Factor 1 consisted of three items which related to motivation. Factor 2 consisted of six items which related to physical symptoms. Factor 3 consisted of six items which related to symptoms of autonomic imbalance. These three factors explained only 18.2% of total variation. The mean SCL‐S value was quite high in the groups characterized by intro‐version (p<0.01), having no one to consult (p<0.05), and not having a hobby (p<0.01). The higher health satisfaction score was, the lower the mean value of the SCL‐S and this was significant (p<0.01). Multiple regression analysis was conducted to predict SCL‐S scores by other variables. Significant standardized partial regression coefficient items increasing the SCL‐S value were introversion trait (p<0.05), not having a hobby (p<0.05), and health dissatisfaction (p<0.01). Among these three variables, health dissatisfaction contributed most to the SCL‐S. The adjusted coefficient of determination was 0.185. These results raise the possibility that the SCL‐S can be based on division into three different scales. Internal consistency was nearly acceptable with the adoption of an alpha value over 0.8. In addition, health satisfaction was most closely related to subjectively reported stress or stress response judged by SCL‐S.
Trichloroethylene Induced Cancer in Animals and Its Relevance to Humans
Authors: Green Trevor
Published: February 2008

Trichloroethylene Induced Cancer in animals and its relevance to Humans : Trevor Green. Zeneca Central Toxicology Laboratory—Tri‐chloroethylene has been manufactured on an industrial scale since the beginning of this century. During that time widespread human exposure has occurred in industry and in the general population through the environment and from its uses in medicine, food and consumer products. Following the discovery in 1976 that trichloroethylene was an animal carcinogen, there have been numerous animal toxicology and human epidemiology studies evaluating the risks associated with exposure to this chemical. Tri‐chloroethylene has been shown to cause tumours in both rats and mice in lifetime bioassays, principally liver and lung tumours in the mouse and kidney tumours in the rat. The mechanisms involved in the development of these tumours have been studied in detail and have been shown to be either species specific or a result of the use of cytotoxic dose levels. There is little or no evidence for genotoxicity playing a major role in these mechanisms. In mice, liver tumours are associated with peroxisome proliferation and increased cell division, the lung tumours are linked to cell damage and increased cell division. None of these effects are seen in rats due to metabolic and pharmacokinetic differences nor can they be replicated in human tissues. The low incidences of rat kidney tumours seen in some cancer bioassays appear to be linked to high dose toxicity. Human epidemiology studies based on large well defined cohorts support the findings of the mechanistic studies in animals and the overall conclusions that trichloroethylene is not a cancer hazard at current occupational and environmental levels.
A Retrospective Cohort Study on Digestive Cancer in the Rubber Tire Industry in Shanghai
Authors: Chen Jigang , Wei Xing , You Xueyun
Published: February 2008

A Retrospective Cohort Study on Digestive Cancer in the Rubber Tire Industry in Shanghai: Jigang Chen, et al. Shanghai Institute of Industrial Hygiene and Occupational Diseases—8,316 subjects, who had been employed in three tire factories in Shanghai for more than 1 year before December 31, 1972, were investigated in a retrospective cohort study to ascertain the relationship between digestive cancer and the job types in the rubber tire industry in Shanghai. Every subject was assigned to one of 27 jobs grouped into 8 types. The observation period was from January 1, 1967 to December 31, 1988. The Results show that several sites of cancer in the digestive system were associated with some main jobs in factories for both sexes. For example, stomach and liver cancers in workers in milling (SIR=202.8 and 229.2), inner tube curing (SIR = 231.3 and 252.3) and material handling (SMR = 209.6 for stomach cancer) in males; pancreatic cancer in tire curing (SIR = 349.4) in males and in inner tube and tire buildings (SMR = 372.5) in females; esophageal cancer in the production of non‐tire products (SMR = 275.31) in males; and rectal cancer in Building and Multiple jobs for non‐tire work in males (SMR = 483.7) and females (SMR = 245.0). The authors thought the high incidence of cancer in the digestive system was a prominent phenomenon in several types of jobs in the rubber product manufacturing industry.
Pulmonary Function in Jute Dust‐Exposed Workers: A Dose‐Response Relationship
Authors: Chen Jie , Lou Jiezhi , Guo Xiaofang , Zhou Chen
Published: February 2008

Pulmonary Function in Jute Dust‐Exposed Workers: A Dose‐Response Relationship: Jie Chen, et ai. Department of Pneumoconiosis, China Medical University School of Preventive Medicine—Pulmonary function tests were carried out on 488 jute‐exposed workers in a jute mill and 332 control workers. An industrial hygiene survey was also conducted. Most workers in the mill were exposed to dusts containing less than 6% silica, whereas a few workers were exposed to dusts containing approximately 10‐16% silica. The cumulative dose of dust exposure [dust level (mg/m3) X exposure year (yr)] was used as an exposure index to relate pulmonary function injury in jute workers. The results showed that jute workers had lower percentages of predicted pulmonary function than those of control workers. As the cumulative dose of dust exposure increased, average levels of pulmonary function (FVC, FEV1, MMF, V50, V25) in smoking male jute workers and V50, V25 in nonsmoking female jute workers significantly declined, and pulmonary function abnormalities (less than 80% of predicted FEVt or less than 70% of predicted V50) significantly increased as the cumulative dose of dust exposure increased. Examination of the effects of dust exposure and smoking on pulmonary function injury showed that not smoking but jute dust exposure was a factor associated with the decline in pulmonary function; Moreover, smoking interacted with dust exposure in causing declines in FEV1 Our results demonstrated that there is a dose‐response relationship between dust exposure and pulmonary function injury in jute workers. Based on this dose‐response relationship and by using the life‐table method, an exposure limit for jute dust was proposed as 4 mg/m3.
Cancer Mortality among Carbon Workers in China: Retrospective Cohort Study
Authors: Liu Ning , Wang Zhongxu , Dong Depu , Chen Kejie , Qin Lijun
Published: February 2008

Cancer Mortality among Carbon Workers in China: Retrospective Cohort Study: Ning Liu, et al. Institute of Industrial Health Anshan Iron & Steel Complex—A retrospective cohort study was performed on a group of 6,635 male workers employed for more than 15 years during the period 1970‐1985 in seven factories including the carbon plants and the potroom and carbon department in an aluminium reduction plant. The SMRs for lung cancer and liver cancer among the workers highly exposed to coal tar pitch volatiles (CTPV) were 4.30 (p<0.01) and 2.25 (p<0.01), respectively. The SMRs for lung cancer and cancer of the esophagua among moderately CTPV‐exposed workers were 1.52 (p<0.05) and 5.46 (p < 0.01) respectively. Results showed that the numerous deaths from lung cancer were correlated with CTPV in the carbon‐producing process in carbon plants.
Assessment of Workers’ Exposure to Antimony Trioxide in Korea
Authors: Kim Ki‐Woong , Choi Byung‐Soon , Kang Seong‐Kyu , Kim Hyeon‐Yeong , Park Sang Shin , Cho Young‐Sook , Song Moon‐Gi , Moon Young‐Hahn
Published: February 2008

Assessment of Workers’ Exposure to Antimony Trioxide in Korea: Ki‐Woong Kim, et al. Industrial Health Research Institute, KISCO—The assessment of workers’ exposure to antimony trioxide was conducted for the workers at three antimony trioxide factories located in Kyeonggi‐do, Chungnam, Cheonnam, Korea during the period of September 4 to October 28, 1995. The objective of this study was to investigate any exposure of workers to antimony. The results were as follows: 1. Mean of the total antimony concentration in the air near the workplace was 0.0223 mg/m3 in the oxidation part and 0.2806 mg/m3 in the packing part (p<0.05). 2. Mean of the respirable antimony concentration in air near the workplace was 0.0028 mg/m3 in oxidation and 0.0034 mg/m3 in packing (p<0.05). 3. The average urinary antimony level in the oxidation part was 0.1827 mg/g creatinine and that of packing part was 0.1371 mg/g creatinine. But they were not statistically significant (p>0.05).
Working in Moderate Cold: A Possible Risk to Health
Authors: Griefahn Barbara , Mehnert Peter , Bröde Peter , Forsthoff Alfons
Published: February 2008

Working in Moderate Cold: A Possible Risk to Health: Barbara Griefahn, et af. Institute for Occupational Physiology, University of Dortmund—Many worktasks in the food industry are carried out in moderately cold climates (— 5 to 15°C), a situation which is assumed to contribute to the genesis and manifestation of several chronic diseases. The present report concerns a cross‐sectional study, in which 1,213 workers in cold environments, mainly from distributors, meat productions, and from breweries completed an extended questionnaire where personal variables and a large spectrum of working conditions, of acute and chronic symptoms, complaints and diseases were ascertained. High prevalences were found for non‐specific symptoms, gastrointestinal complaints, pains in the back and in the joints, rheumatic and bronchitic complaints, colds, hearing problems, and the symptoms of the white finger disease. Some of them were significantly associated with the climate at the workplace, particularly with cold, changes in temperature, and drafts. The results support the hypothesis that moderate cold at the workplace constitutes a health risk and form the basis for further, more directed analytical studies.

Key words: Food industry, Thermal sensation, Health disorders, Working conditions, Cross‐sectional study
Estimation of Trunk Inclination by Means of an Inclinometer
Authors: Seo Akihiko , Kakehashi Masayuki , Tsuru Satoko , Yoshinaga Fumitaka
Published: February 2008

Estimation of Trunk Inclination by Means of an Inclinometer: Akihiko Seo, et af. Department of Public Health, Hiroshima University School of Medicine—In an effort to estimate trunk inclination by means of a simple inclinometer, a theoretical model analysis was carried out to clarify the relation between “true” trunk inclination and the inclinometer reading. The effects of inclinometer location on the trunk, working posture, and weight handled were also investigated experimentally. The theoretical model was based on work by Anderson et a!. to estimate pelvic rotation from trunk inclination. The theoretical results indicated that the relation between trunk inclination and the inclinometer reading would change according to the location of the inclinometer. The curves were concave, straight, and convex when the inclinometers were fixed on the trunk at low, intermediate, and high levels, respectively. In the experimental study, twelve male subjects held 1,5, and 1 0 kg boxes at 0, 20, 40, and 60 cm from the floor in forward‐bending and squatting postures. The inclinometers were fixed on the back at L4, Th12, and Th5. The relation between trunk inclination and the inclinometer reading in measurement data showed concave, straight, and convex curves at L4, Th12, and Th5, respectively, as the theoretical model analysis had indicated. At L4 and Th5, however, the relation could be regarded as linear because the coefficients of determinations (R2) of the theoretical models calculated by the regression analyses agreed closely to those of the simple linear models. The difference between the forward‐bending and squatting postures was large at L4, but small at Th12 and Th5. The effect of the weight handled was small and negligible in making these estimates.
Prevention of Work‐Related Falling/Slipping Accidents in Taiwan
Authors: Li Kai Way
Published: February 2008

Prevention of Work‐Related Falling/Slipping Accidents in Taiwan: Kai Way Li. Department of Industrial Management, Chung‐Hua Polytechnic Institute—The prevention of slipping and falling accidents in the workplace has received very limited attention in Taiwan. Official statistics on work‐related falling accidents in 1994 revealed that subsequent losses from those accidents were significant. The R.O.C. Institute of Occupational Safety and Health (IOSH) recently recommended that safety footwear be worn in certain private sectors, but standards governing the slip‐resistance of sole materials for safety footwear have not yet been established. In this study, a Chung‐Hua Polytechnic Institute machine is designed and fabricated to measure the friction coefficients of shoes, floor, and contamination combinations. A model to continuously improve work place safety is also presented to reduce the risk of slipping/falling accidents.
Cytochrome P450 Isoforms and the Metabolism of Volatile Hydrocarbons of Low Relative Molecular Mass
Authors: Nakajima Tamie
Published: February 2008

Cytochrome P450 Isoforms and the Metabolism of Volatile Hydrocarbons of Low Relative Molecular Mass: Tamie Nakajima. Department of Hygiene, Shinshu University School of Medicine—Cytochrome P450 isoforms responsible for the metabolism of volatile hydrocarbons of low relative molecular mass are reviewed. Rat CYP2E1 catalyses the metabolism of all hydrocarbons with a low Km, whereas CYP1A1/2, CYP2B1/2 and CYP2C11/6 catalyse the metabolism of many hydrocarbons with a high Km, although the contribution of the first two is minimal. The metabolism of hydrocarbons is affected by physiological and environmental factors, changes in the expression of P450 isoforms and the affinity of the chemicals for the isoforms. Human CYP2E1 also catalysed all of the hydrocarbons investigated, with the same kinetics as that of rat CYP2E1. Human CYP2B6 and CYP2C8 catalyse the metabolism of some hydrocarbons, but with slightly different catalytic properties for the formation of o‐ and p‐cresol from toluene. Although CYP2B1/2 is poorly expressed in liver microsomes from control rats, CYP2B6 is found immunochemically to be constitutive in human liver microsomes. Human CYP1A2 also catalyses the metabolism of some organic solvents, with varying kinetic and catalytic features. The contribution of human CYP3A3, CYP3A4 and CYP3A5 to metabolism is very low. In conclusion, CYP2E1 is an essential isoform for the metabolism of hydrocarbons in both rodents and humans, especially at low concentrations.
Diver's Lung Function: Influence of Smoking Habit
Authors: Suzuki Shinya
Published: February 2008

Diver's Lung Function: Influence of Smoking Habit: Shinya Suzuki. Japan Maritime Self‐Defense Force Undersea Medical Center—To assess the influence of smoking habit on divers’ lung function, we measured static lung volumes, dynamic lung volumes and flows and diffusing capacity for carbon monoxide (DLco) on 71 healthy, male, JMSDF active‐duty uniformed divers (46 smokers and 25 nonsmokers). All measurements were conducted with an automated system (CHESTAC‐25V model; Chest Ltd., Tokyo, Japan). Comparison of lung functions between smokers and nonsmokers was assessed using a Mann‐Whitney rank‐sum test. Vital capacity in smokers was 120.4 ±11.3 (mean ± SD)% of the predicted value for age and height, and in nonsmokers was 119.9 ± 15.1%. In the static lung volumes there were no differences between smokers and nonsmokers. Although the forced vital capacity (FVC), the forced expired volume in the 1st second (FEV10), and the forced expiratory flow rate at 75% of FVC expired (V75) showed no difference between two groups, the peak expiratory flow rate (PEFR) in smokers was lower than that in nonsmokers (p<0.005). The forced expiratory flow rate at 25% of FVC expired (V25) showed no difference, while the DLco in smokers was worse than in nonsmokers (p<0.01). Lung Volumes of the divers in JMSDF were larger than predicted values in the general population. Judging from the ratio of the residual volume to total lung capacity, emphysematous change with aging was negative. PEFR, FEV10 and V75 depend on the ventilatory muscle strength and diameter of the large respiratory tract. To investigate the reason why only PEFR was lower in smokers than nonsmokers in this population, more data should be collected. The finding of no difference in V25 between the two groups could not indicate that smokers had emphysematous change compared to nonsmokers. The decrease in DLco with age in smokers compared to nonsmokers, however, suggested the possibility of emphysema. Considering that emphysema is a contraindication for diving, a diver should not smoke.
Prolonged Exposure to Industrial Noise: Cochlear Pathology does not Correlate with the Degree of Permanent Threshold Shift, but is Related to Duration of Exposure
Authors: Śliwińska‐Kowalska Mariola , Jedlińska Urszula
Published: February 2008

Prolonged Exposure to Industrial Noise: Cochlear Pathology does not Correlate with the Degree of Permanent Threshold Shift, but is Related to Duration of Exposure: Mariola Śliwińska‐Kowalska, et al. Department of Physical Hazards, The Nofer Institute of Occupational Medicine—It has been shown that the damaging effects of noise on the mammalian inner ear strongly depend upon parameters of exposure, such as the intensity of noise, the duration of exposure, etc., but the relationship between permanent hearing loss and cochlear damage still remains unclear. In this study, we were interested in the damaging effects of exposure to typical steady‐state, wide‐band industrial noise acting for as long as 12 weeks on guinea pigs. The aim of the study was to evaluate the relationships among the duration of exposure to industrial noise, the level of permanent hearing loss and the degree of cochlear injury and to assess the possible mechanisms of industrial noise‐induced hearing loss. The results of the study indicate that 1) prolonged exposure to industrial noise causes in guinea pigs a relatively fast increase in permanent hearing threshold shift (PTS) up to 30 dB, which reaches the asymptotic level after 4 weeks of exposure; 2) the first 30 dB of PTS is caused almost exclusively by the damage to outer hair cells; 3) the degree of cochlear damage is not related to the level of permanent threshold shift; 4) the progression in cochlear pathology depends upon the duration of exposure; 5) both micromechanical and metabolic mechanisms seem to be involved in the development of industrial noise‐induced hearing loss.
Equilibrated Vapor Concentrations for Bicomponent Organic Solvents
Authors: Hori Hajime , Tanaka Isamu
Published: February 2008

Equilibrated Vapor Concentrations for Bicomponent Organic Solvents: Hajime Hori, et al. Department of Environmental Management I, School of Health Sciences, University of Occupational and Environmental Health, Japan—The equilibrated vapor concentrations for bicomponent organic solvents of toluene‐o‐xylene, methanol‐ toluene and methanol‐o‐xylene mixtures were measured at various compositions. The equilibrated vapor concentration of each component for the toluene‐o‐xylene system was almost proportional to its liquid phase molar fraction. For the methanol‐ toluene and the methanol‐o‐xylene systems, however, methanol vapor occupied 80‐90% of the total organic vapor in the gas phase, even the molar fraction of methanol in the liquid phase was less than 5%. For the toluene‐o‐xylene system, because the solution was regarded as an ideal solution, the equilibrated vapor concentrations could be estimated from the saturated vapor concentrations of pure solvents and their liquid molar fractions. On the other hand, the methanol‐ toluene and the methanol‐o‐xylene systems could not be regarded as ideal solutions. For these systems, the equilibrated vapor concentrations could be estimated by introducing the activity coefficients calculated with the Margules equation.
Immune Response in Guinea Pigs Injected with Insoluble Beryllium Compounds
Authors: Yoshida Tsutomu , Shima Shogo , Nagaoka Kaoru , Kurita Hideki , Ootani Naoko , Asada Yasuki , Taniwaki Hiroshige , Morita Kunihiko
Published: February 2008

Immune Response in Guinea Pigs Injected with Insoluble Beryllium Compounds: Tsutomu Yoshida, et al. Department of Public Health, Fujita Health University School of Medicine—The changes in immune response of guinea pigs intrapleurally injected once with beryllium oxide (BeO) or beryllium copper alloy (Be‐Cu) were examined. To evaluate the changes in immune response of guinea pigs, two indicators, beryllium lymphocyte transformation test (Be‐LTT) and complement hemolytic activity (CH50), were used. The BeO or Be‐Cu injection groups was divided three groups, a high concentration injection group (36 μg Be dose), a low concentration injection group (3.6 jug Be dose) and the control group. The Be‐LTT and CH50 were determined in the blood of guinea pigs at 4, 8 and 16 weeks after Be administration. The Be‐LTT value at the 4th week in the BeO groups (a high or low concentration injection group, respectively) showed a statistically significant increase (p <0.01) compared with that of the control. In the Be‐LTT value for BeO at 8 and 1 6 weeks after Be injection and the Be‐Cu groups, there were no statistical difference between the Be administration groups and the control. On the other hand, only the CH50 of the high concentration group at the 8th week in the BeO injection group was significantly decreased (p <0.01) compared with that of the control. In the other Be injection group, no significant changes in the CH50 was observed compared with the control group. On the basis of the results observed in the present study, there may be a slight difference in the effect on the immune response of guinea pigs caused by BeO or Be‐Cu administration. The immunotoxicity of Be in guinea pigs may manifest itself more intensely in the cellular immune response than in the humoral immune response.
Electrophysiological and Biochemical Effects of Exposure to 2,5‐Hexanedione on Peripheral Nerve in Experimental Diabetic Rats
Authors: Kimura Takashi , Misumi Junichi , Goto Toshio , Zhao Wenyuan , Aoki Kazuo
Published: February 2008

Electrophysiological and Biochemical Effects of Exposure to 2,5‐Hexanedione on Peripheral Nerve in Experimental Diabetic Rats: Takashi Kimura, et al. Department of Public Health and Hygiene, Oita Medical University—Both 2,5‐ hexanedione (2,5‐HD) and diabetes mellitus (DM) cause peripheral neuropathy. Workers with asymptomatic DM could possibly be exposed to n‐ hexane converted to 2,5‐HD in liver. To clarify 2,5‐HD influences on peripheral nerves in DM, electrophysiological and biochemical changes in DM rats were compared in 2,5‐HD treated and untreated groups. Four groups of rats were studied: the Control group consisted of non‐diabetic rats treated with a placebo: the HD group, of non‐diabetic rats treated with 2.5‐HD; the DM group, of diabetic rats treated with a placebo: the DM+HD group, of diabetic rats treated with 2.5‐HD. 2,5‐HD was administered at 100 mg/kg/day, five days a week for 8 weeks. The motor nerve conduction velocity (MCV) and motor distal latency (DL) in the rat 's tails and glucose, fructose, sorbitol and myo‐ inositol levels in the sciatic nerves were measured. The MCV in the DM+HD group was significantly reduced from the 4th week compared with those in the other groups. 2,5‐HD had no influence on the levels of glucose, fructose, sorbitol and myo‐inositol in either the diabetic or non‐diabetic group. These results indicated that exposure to 2,5‐HD hastened the onset of peripheral neuropathy in experimental diabetic rats. This study indicates that 2,5‐HD in combination with DM enhances the neurotoxicity. But the mechanisms of the neurotoxic interactions between 2,5‐HD and DM are still unknown. It can be hypothesized that workers with hyperglycemia can suffer from neuropathy due to exposure to n‐hexane earlier than those without hyperglycemia.
A SAS Program for the Stratified Analysis of Follow‐Up Data
Authors: Honda Yasushi , Macaluso Maurizio , Brill Ilene
Published: February 2008

A SAS Program for the Stratified Analysis of Follow‐Up Data: Yasushi Honda, et al. Environmental Health Sciences Division, National Institute for Environmental Studies—Mantel‐ Haenszel (M‐H) estimators are robust measures of association for the stratified analysis of epidemiologic studies. This paper describes a SAS macro developed to compute the M‐H rate ratio(RR) for a binary exposure and its confidence interval from follow‐up data. The program accommodates a virtually unlimited number of stratification factors, allows setting the confidence level, and can easily be applied to the analysis of multi‐level categorical exposure variables. Printed output includes stratum‐specific rates and RRs and summary M‐H RRs and confidence intervals. Summary measures of association are meaningful only if effects are homogeneous across strata. The printed output of the program allows inspection of stratum‐ specific rate ratios to check this important assumption.
Relationship between Body Weight and Somatological Factors by Sex and Age
Authors: Fukuda Yoshiharu , Futatsuka Makoto
Published: February 2008

Relationship between Body Weight and Somatological Factors by Sex and Age: Yoshiharu Fukuda, et al. Department of Public Health, Kumamoto University Medical School—To determine the relationship between relative body weight and the somatological factors of blood pressure, serum lipid, liver function and blood sugar by sex‐age groups, and to evaluate the effectiveness of BMI as a screening index for abnormality in blood tests, we studied cross‐sectional health examination data drawn from a population consisting of 6,989 officials aged 18‐65 years in municipalities in Kumamoto prefecture, Japan. Results showed the association between body mass index (BMI) and somatological factors is very strong in young adult males, but weak in middle‐aged males. Furthermore, the receiver operating characteristic curve analysis showed that BMI is valid in screening for blood test abnormalities in young adult males. From these results, BMI was found to be a comprehensive parameter of health status and an efficient screening index for blood tests in young adult males. The intervention in obesity appears to be a most advisable goal in primary prevention in young adult males.
Occupational Exposure to Low Concentrations of Organic Solvents in Shipyards
Authors: Katsuyama Hironobu , Tsuchiya Goro , Saijoh Kiyofumi , Sumino Kimiaki
Published: February 2008

Occupational Exposure to Low Concentrations of Organic Solvents in Shipyards: Hironobu Katsuyama, et al. Department of Public Health, Kawasaki Medical School—Because shipbuilders have to use organic solvents in very confined spaces, they have a higher risk of inhaling the solvents than workers working in an open space. The working environment at 14 workplaces with very limited space was examined and biological monitoring was performed on 18 workers who worked in such places. Out of 14 workplaces, only 4 did not exceed the assessment criterion. Although exhaust ventilation fans and chemical cartridge respirators were used to avoid exposure to solvent vapor irrespective of the concentrations of solvents, biological samples revealed inhalation of solvent vapor. Urinary excretion of hippuric acid and methylhippuric acid varied from 0.07 to 0.92 g/ g Cr and 0.02 to 0.42 g/g Cr at the end of the shift, respectively. Concentration of toluene and xylene in the end‐exhaled air varied from <0.1 to 5.0 ppm and <0.1 to 10.6 ppm, respectively. The concentration of metabolites in urine and the concentration of solvent in the end‐exhaled air revealed a strong correlation in the case of xylene but not toluene. Because of the limitation of space, the mean concentration of solvents in the working environment is not always available in shipyards, which make it difficult to estimate the amounts inhaled by workers. Biological monitoring of the end‐exhaled air provides useful information to make it possible to avoid continuous and/or unexpected exposure of workers who have to work in a very limited space.
Liver Damage among Environmental Disinfestation Workers
Authors: Tomei Francesco , Biagi Marco , Baccolo Tiziana Paola , Tomao Enrico , Giuntoli Paola , Rosati Maria Valeria
Published: February 2008

Liver Damage among Environmental Disinfestation Workers: Francesco Tomei, et al. Occupational Medicine Dept., “La Sapienza” University, Rome—It has been reported that exposure to high doses of insecticides can damage the liver. It is now becoming apparent that even exposure to low doses may affect the liver and blood. Studies on the effects on the health of disinfestation workers are scant. This study investigated 37 males doing environmental disinfestation work. They all employed the same types and amounts of pesticides. They were compared with 60 controls not exposed to hepatotoxic substances. In the presence of a physician, all subjects completed a clinical‐history questionnaire. They all underwent a general clinical examination and specific blood chemistry tests were done. In the exposed group we found liver test values to be higher than controls (p<0.001), including AST (pcO.025), alkaline phosphatase (p<0.001), and total bilirubin (p<0.001). We found no abnormal hematological changes. The findings indicate that the use of pesticides in environmental disinfestation alters liver function and that this screening protocol is valid for identifying subjects at risk for hepatotoxicity.
No Evidence for a Diuretic Effect of Benzisothiazolinone (BIT) in an Experimental Animal Model Employing Anaesthetised Rats
Authors: Hellman Björn , Sjöquist Mats , Anundi Helena , Edling Christer
Published: February 2008

No Evidence for a Diuretic Effect of Benzisothiazolinone (BIT) in an Experimental Animal Model Employing Anaesthetised Rats: Bjorn Hellman, et al. Department of Occupational and Environmental Medicine, University Hospital, Uppsala—The diuretic effects of benzisothiazolinone (BIT), vapours from a water‐based paint, and the reference compound furosemide, were investigated in an experimental model employing anaesthetised rats. BIT (90 mg/kg body weight) was given orally 2 or 12 hr before the rats were anaesthetised. The paint vapours and furosemide were administered during anaesthesia. Urinary flow, osmolality, urinary concentrations of sodium and potassium, and blood pressure were measured as indicators of renal function. Whereas all these parameters were significantly affected after an injection with furosemide, neither BIT nor the vapours from the paint were found to induce any biologically significant effects. Provided that the experimental model with anaesthetised rats is relevant when studying the mechanisms for diuresis in man, the results of the present study suggest that previously reported problems with frequent urination among painters working with water‐based paints are symptoms not related to a direct diuretic effect of BIT or the vapours from these paints.
Effects of Breathing Resistance While Inhaling 3% Carbon Dioxide during Steady‐State Exercise
Authors: Takahashi Masayoshi , Mano Yoshihiro , Shibayama Masaharu , Yamami Nobuo
Published: February 2008

Effects of breathing resistance while inhaling 3% carbon dioxide during steady‐state exercise: Masayoshi Takahashi, et al. National Institute for Resources and Environment—The purpose of the study was to determine the effects of breathing resistance on the human body while inhaling 3% carbon dioxide and to evaluate the appropriateness of self‐contained self‐rescuer (SCBA) criteria in the Japan Industrial Standard (JIS). Eight male subjects volunteered for the study and breathed both normal air and 3% carbon dioxide with both low and high breathing resistance during moderate steady‐state exercise. The high breathing resistance produced a pressure level that was almost the same as the upper permitted limit for SCBA in the JIS. Increasing the breathing resistance did not cause any significant effect on the human body while breathing normal air but, in the case of 3% carbon dioxide, the high resistance increased end‐tidal carbon dioxide significantly and caused strong distress in the test subjects. Based on these results, it is recommended that carbon dioxide levels be kept low to improve human performance while wearing SCBAs.
Onset of Peptic Ulcer and Its Relation to Work‐Related Factors and Life Events: A Prospective Study
Authors: Sugisawa Atsuko , Uehata Tetsunojo
Published: February 2008

Onset of Peptic Ulcer and its Relation to Work‐Related Factors and Life Events: A Prospective Study: Atsuko Sugisawa, et al. Department of Mental Health Administration Studies, National Institute of Mental Health, National Center of Neurology and Psychiatry—Although peptic ulcer (PU) is counted as one of the various work‐related diseases, little is known about the risk factors other than health habits. The authors used data from the Japan Workers Stress and Health Survey—an 18‐month follow‐up study—to ascertain whether psychosocial factors play any role in the development of PU in the working population. The subjects were 9,204 men, working at various occupations and firms, aged 30 through 59 years, who had no prior history of PU at baseline. People with extremely severe life event stress had an increased risk of PU compared with those who had no such experience. An increased risk was found when the frequency of late night work was 10‐12 times a month compared with none. Five items related to perceived work overload—too much responsibility, poor relations with superior, understaffing, excess of evening/holiday business meetings, and physically too tiring —were each positively associated with PU. Life event stress, frequency of late night work, and perceived work overload were all independently associated with the onset of PU after controlling for age and smoking. These results provide evidence that psychosocial factors play an important role in the development of PU.
The Effect on Workers' Knowledge, Attitudes and Behavior of a Group Health Care Program for Small‐Sized Plants in Pusan, Korea
Authors: Sohn Hae‐Sook , Lee Soo‐Kyung , Lee Chae‐Un
Published: February 2008

The Effect on Workers' Knowledge, Attitudes and Behavior of a Group Health Care Program for Small Sized Plants in Pusan, Korea: Hae‐Sook Sohn,et al. Department of Preventive Medicine, Medical College, Inje University—To investigate the effect of a group health care program by observing differences in knowledge, attitudes and behavior (K, A and B) regarding occupational health services, a cross sectional survey of 201 workers served under a Group Health Care Program (GHCP) was carried out from November, 1995 to January, 1996. The K, A and B of workers were assessed by questionnaires about occupational health services. Subjects were divided to two groups according to the duration they had been served with group health care (Group I: <1 year, Group II: > = 3 years). K, A and B were compared in the two groups. All measures of K, A and B related to occupational health services, except satisfaction with the GHCP, were higher in Group II than in Group I. Group II was significantly higher in K, A and B (P<0.01) about personal protective equipment. This study confirmed that workers' K, A and B were positively influenced by the GHCP. The fact that the percentages of workers wearing personal protective equipment (PPE) and of proper use of PPE in Group II were significantly higher indicates that GHCP may be effective in the prevention of some aspects of occupation‐related diseases.
Protective Efficacy of Solanum Hainanense Hance during Hepatotoxicity in Male Mice with Prolonged and Small Oral Doses of Trinitrotoluene
Authors: Thai Nguyen Phuc , Van Trung Le , Hai Nguyen Khac , Huynh Le
Published: February 2008

Protective efficacy of Solanum Hainanense Hance During Hepatotoxicity in Male Mice with Prolonged and Small Oral Doses of Trinitrotoluene: Nguyen Phuc Thai, et al Department of Occupational Health, Military Institute of Hygiene and Epidemiology—A cluster of patients with anemia, aplasia, methemoglobinemia and hepatotoxicity were found among workers in explosive material factories in Vietnam. Trinitrotoluene (TNT) was suspected of causing the disorders. This study aims to evaluate the use of Solanum hainanense Hance for liver protection of white mice which were poisoned with prolonged and small oral doses of TNT. Thirty‐six mice were assigned equally to 3 groups: control group, poisoned group and protected group. The poisoned group received a TNT oral dose of 100 mg/kg body weight daily 6 times weekly for 6 wk, and the protected group were administered a Solanum hainanense hance solution dose of 6 g/kg body weight daily 4 h before receiving the same dose as the poisoned group. They were followed up for 6 wk. Body and liver weights were measured, tissues were histopathologically examined and laboratory tests (glucose, MetHb, ‐SH concentrations and serum AST, ALT) were done at the end of the experiment. The results were as follows: Serum AST and ALT activities were significantly different in the three groups (Control group: 280 ±107 and 55.2 ± 22.5 U/l; Poisoned group: 486 ± 267 and 102.8 ± 44.9 U/l; Protected group: 288 ±164 and 78.3 ± 9.6 U/l). MetHb, glucose and ‐SH concentrations were changed by TNT, and these changes were increased in the Solanum hainanense hance‐protected group but the increase was not statistically significant. The cut off point at 1483 mg and ratios of hepatomegaly were significantly different in the three groups (Control group: 1/12; Poisoned group: 10/ 12; Protected group: 6/12). The cut off point at 58.7% and ratios of increase in density of the liver and of body weights were significantly different in the three groups (Control group: 1/12; Poisoned group; 6/12; Protected group 3: 1/12). Histological examination of the livers showed normal histological features in control mice, histopathological lesions in TNT‐poisoned mice and the alleviation of TNT‐induced lesions in protected mice. TNT has caused histopathological lesions and changed liver function tests. These lesions and changes in biochemical tests could be significantly restricted by Solanum hainanense Hance solution. The results suggest that Solanum hainanense hance could protect against TNT‐induced liver damage.