Journal of Occupational Health
Online ISSN : 1348-9585
Print ISSN : 1341-9145
ISSN-L : 1341-9145
Volume 44, Issue 6
Displaying 1-10 of 10 articles from this issue
Review
  • Yuichi YAMADA, Masao ISHIZAKI, Ikiko TSURITANI
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 373-384
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    Obesity has been recognized as a global epidemic threatening health and life. Today in Japan, obesity defined as a body mass index (BMI) greater than 30 kg/m2 is found in 2-3% of adults, but one in five men and women is defined as overweight with a BMI greater than 25, and thus the prevention of obesity should be targeted in health promotion services at worksites. Vigorous research is required in workplaces because a few work-related factors, such as socioeconomic status including job and position, job stress, extended work including overtime, shift or night work and sedentary work, have been suggested in the literature to promote weight gain and abdominal fat accumulation. The obesity prevention programs at worksites should not be focused on reducing weight in a few current obese workers, but on maintaining the current weight in the majority of workers to prevent the development of obesity and its consequences. The measurement of waist circumference is indispensable for assessing the risk of coronary heart disease (CHD) in overweight and obese workers, and those at a high risk of CHD should be referred to medical professionals outside the workplace. The education programs at worksites on dieting and exercise for maintaining body weight should be conducted as a part of the whole lifestyle improvement programs on both a population and an individual basis. Considerable knowledge and skills for the education program are required for health care persons at worksites. Otherwise, professional support should be provided to them by some occupational health service agencies.
    Download PDF (1307K)
Originals
  • Fumi TAKEDA, Eise YOKOYAMA, Takeo MIYAKE, Takashi OHIDA
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 385-390
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    Mental health status and its association with job factors was explored in 55 social workers at seven social welfare offices in a prefecture in Japan. We found that 28 social workers (50.9%) scored in the “high burnout” category and 10 (18.2%) had from moderate to severe depression. There was a significant correlation between the burnout score and the SDS score. The burnout score and SDS score of male social workers were both significantly higher than those of male clerical staff. Male social workers had significantly higher burnout scores than females. Multiple regression analysis showed that burnout was significantly related to a large percentage of time spent on home visits per typical working day and low job satisfaction. Depression was significantly associated with low job satisfaction. These results suggest that social workers with lower job satisfaction may be at higher risk of burnout and depression, and that social workers who devote a large percentage of their work time to home visits may be more likely to suffer from burnout.
    Download PDF (458K)
  • Jun OJIMA
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 391-397
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    An experimental mock-up push-pull ventilation system was constructed in a laboratory and a dummy worker was placed in its ventilation area (uniform flow field). Within the uniform flow field, organic solvent work was modeled by setting up an alcohol vapor generator and a working table in front of the dummy worker. Reverse flow was observed in the breathing zone of the dummy worker when it was positioned in the uniform flow originating from behind the worker. The experiments showed that reverse flow increased the worker’s contaminant exposure significantly. With the 1.0 m/s uniform flow originating from behind the worker, the alcohol concentration in the breathing zone exceeded 300 ppm due to the reverse flow, but it was too low to be detectable when the worker’s orientation relative to the uniform flow was 90 degree. In order to control the reverse flow and minimize the contaminant exposure, the author invented a prototype of a reverse flow preventing system. The reverse flow preventing system reported in this study was designed to be set up in a position between the worker and the working table. It decreased exposure by means of locally supplied air blowing which blocked the reverse flow and contaminant transportation from the source.
    Download PDF (1418K)
  • Akizumi TSUTSUMI, Kazunori KAYABA, Makiko NAGAMI, Akiko MIKI, Yuri KAW ...
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 398-407
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    The validity of Siegrist’s effort-reward imbalance model was examined in Japanese workers: 105 dental technicians, 902 employees of production companies, and 2, 827 selected from staff of hospitals. After controlling for possible confounders, levels of the two stress measures, ‘effort-reward imbalance’ and ‘overcommitment’, were similar for both genders. The effort-reward imbalance was most prevalent in the 25-30 age employees and then decreased with age, but the level of overcommitment increased with age. Those with lower educational attainment and others who reported working long hours were more often exposed to effort-reward imbalance and those in the private sector reported higher overcommitment levels than their respective counterparts. Hospital staff (predominantly nurses) had almost twice as high a level of effort-reward imbalance as production workers. A review of empirical studies confirmed validity of the criterion with respect to a self-reported health outcome and the responsiveness of the measures to organizational changes. Nevertheless, the low prevalence of an effort-reward imbalance (originally formulated by Siegrist’s group on European samples) in Japanese employees seemed to reduce the statistical power of these tests. A subsequent change in exposure prevalence by defining the top quintile of the distribution of the logarithmic-transformed effort-reward ratio resulted in an improvement in the statistical fit. The Japanese evidence indicates promising applicability of the effort-reward imbalance model, particularly if statistical approaches that measure the model’s core notion are extended, and recommendation of repeated measures for exposure. Cross-cultural research on occupational stress is instructive in terms of health science.
    Download PDF (794K)
  • Kunio TSURUMI, Toru ITANI, Norihide TACHI, Toshimasa TAKANISHI, Hatsuk ...
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 408-413
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    This study aims to evaluate the availability of surface-electrode electromyogram (EMG) and acceleration to predict energy expenditure during sedentary work with upper limb movement. The following variables were measured in 12 female subjects: oxygen consumption (VO2), heart rate, EMG from the medial and anterior part of the deltoid muscle, and acceleration of wrist movement. The subjects were requested to perform four different sedentary tasks. In tasks 1, 2 and 3, subjects touched two points on a table (height 70 cm) alternatively. The distance between the two points was 50 cm in tasks 1 and 3, and 100 cm in task 2. The frequency of the movement was 100 touches per minute in tasks 1 and 2, and 152 touches in task 3. In task 4, the points were located vertically on a wall, so they had to move their upper limb vertically in this task. The height of the points was 10 cm below and 40 cm above the acromion height of the subject, and task frequency was 100 touches per minute. The correlation coefficient was 0.285, 0.581 and 0.676, between VO2 and heart rates, VO2 and acceleration, and VO2 and EMG from the deltoid, respectively. The coefficient of determination was 0.648, when employing multiple regression analysis, with acceleration and EMG as independent variables. These results suggest that energy expenditure during sedentary work with upper limb movement can be well estimated by using the data from acceleration of wrist movement and the EMG of the deltoid.
    Download PDF (782K)
  • Seichi HORIE
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 414-420
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    A newly devised earmuff that utilizes an active noise control system and a bone-conduction microphone was examined in an actual working environment where workers are required to communicate under noisy conditions. Thirteen experienced male workers aged 26 to 46 (mean ± SD; 37.5 ± 5.8) engaged in manufacturing steel pipes participated in the study. For 4 h working in a noisy environment (92 to 103 dBA), they used the conventional device (an earphone on one ear and an earplug in the other, and an ordinary microphone) or the new device. After wearing the new device, the temporary threshold shift (TTS) at 4 kHz was lowered (p<0.045, Wilcoxon’s sign rank test) and the number of workers who had TTS was reduced in all frequencies examined (p<0.001, two-way repeated-measures ANOVA). Many workers evaluated the new device superior to the conventional one especially in its “clearness of voice, ” but they did not give the new device a good overall rating mainly because of its heaviness. Although the new device needs improvement, it appears promising as a hearing protector.
    Download PDF (730K)
  • Kui-Cheng ZHENG, Makoto ARIIZUMI
    Article type: Original
    Subject area: Others
    2002 Volume 44 Issue 6 Pages 421-426
    Published: 2002
    Released on J-STAGE: March 28, 2003
    JOURNAL FREE ACCESS
    This study was aimed at investigating the cytokine status and their gene expressions in airways of asthmatic mouse caused by toluene diisocyanate (TDI). After the mice were exposed to TDI vapor for 5 consecutive days, bronchoalveolar lavage (BAL) was carried out and the cells in the BAL fluid were counted. Lung histological test was conducted to analyse the inflammatory status in the airways. Total serum IgE and IL-4 and IL-5 concentrations in the BAL fluid were determined with ELISA kits. RT-PCR was applied to investigate IL-4 and IL-5 mRNA from BAL cells. The airway cell count and histological analysis showed that TDI exposure resulted in airway inflammatory responses characterized by marked infiltration of eosinophils in the central and peripheral airways. Total serum IgE was significantly increased in the TDI-exposed mice. IL-4 and IL-5 productions in the BAL fluid were significantly enhanced in the mice exposed to TDI, but in BAL cells IL-4 and IL-5 mRNA were slightly enhanced without any significant difference compared to the control mice. These results further support the hypothesis that Th2 cytokines are predominantly produced in TDI-induced airway hypersensitivity, but our data were not able to indicate the exact source of these cytokines and we could not determine whether the change in cytokines in the airways was controlled by the gene transcription level.
    Download PDF (811K)
Short Communications
Case Study
feedback
Top