Objectives: Trichloroethylene (TRI) has the potential to cause generalized dermatitis complicated with hepatitis. The guinea pig maximization test (GPMT) also suggests that both TRI and its metabolite trichloroethanol (TCE) exhibit immunogenicity and possible sex differences in guinea pigs. However, TRI and TCE metabolisms in guinea pigs have not been elucidated in detail. The first issue to clarify may be the sex differences in relation to the immunogenicity. Methods: We collected urine from Hartley male and female guinea pigs 24 hours after intracutaneous injection of TRI, TCE or trichloroacetic acid (TCA) during a GPMT and measured the urinary metabolites by gas chromatography-mass spectrometry. Results: After TRI treatment, the amount of TCA was significantly greater in females than males, while there was no sex difference in the total amount (TCA + TCE). TCA was only detected in urine after TCA treatment. Interestingly, not only TCE but also TCA was detected in urine of both sexes after TCE treatment, and the amount of TCA was also greater in females than males. An additional experiment showed that TCE treatment did not result in the detection of urinary TCA in cytochrome P450 (CYP)2E1-null mice TCEbut did in wild-type mice, suggesting the involvement of CYP2E1 in the metabolism from TCE to TCA. The constitutive expression of CYP2E1 in the liver of guinea pigs was greater in females than males. Conclusions: The sex difference in urinary TCA excretion after TRI and TCE treatments may be due to variation of the constitutive expression of CYP2E1.(J Occup Health 2013; 55: 443–449)

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Objectives: Burnout is a psychological consequence of prolonged work stress. Studies have shown that it is related to physical and mental disorders. The safety outcomes of burnout have been studied to a lesser extent and only in the work context. This study explored the effect of burnout on future severe injuries regardless of their context. Methods: A total of 10,062 forest industry employees (77% men, 63% manual workers) without previous injuries participated in 1996 or 2000 in the “Still Working” study examining the work-related antecedents of health and mortality. Burnout was assessed using the Maslach Burnout Inventory-General Survey. Injuries leading to death or hospitalization were regarded as severe. We extracted such injuries from independent national registers. The relationship between burnout and new injuries was analyzed using Cox proportional regression. The analyses were adjusted for age, sex, marital status, and occupational status. Results: There were 788 new injuries over eight years. Injuries were more common among male and manual workers. After adjustments, each one-unit increase in the burnout score was related to a 9% increase in the risk of injury (95% confidence interval: 1.2–1.17). Experiencing symptoms at least monthly was related to a 1.18-fold adjusted injury risk (95% CI: 1.2–1.36). Of the subscales of burnout, exhaustion and cynicism but not lack of professional efficacy predicted injuries after adjustments. Conclusions: In addition to mental and physical disorders, burnout predicts severe injuries. Developing work conditions and optimizing workload may enhance safety and decrease health expenses related to all injuries.(J Occup Health 2013; 55: 450–457)

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Objective: The aim of this study was to analyze the associations between occupational stress, burnout and turnover intention and explore their associated factors among managerial staff in Guangzhou, China. Methods: This cross-sectional study recruited 288 managerial employees from a Sino-Japanese joint venture automobile manufacturing enterprise in Guangzhou. The questionnaire included questions about sociodemographic characteristics, smoking, drinking and physical activity and the Chinese versio ns of the Occupational Stress Indicator (OSI), Maslach Burnout Inventory (MBI), Eysenck Personality Questionnaire (EPQ), Simplified Coping Style Questionnaire (SCSQ) and Social Support Rating Scale (SSRS). The response rate was 57.6%. Stepwise regression analysis was performed to examine the associations between burnout and occupational stress and turnover intention and related factors. Results: The respondents had a high level burnout on the personal accomplishment subscale and had a high prevalence of turnover intention. Neuroticism, psychoticism, job satisfaction, occupational stress and social support were strong predictors of emotional exhaustion. Psychoticism, passive coping, occupational stress, objective support, utilization of support, male gender and job satisfaction were strong predictors of depersonalization. Active and passive coping and job satisfaction were strong predictors of personal accomplishment. Job dissatisfaction and emotional exhaustion were strong predictors of turnover intention.Conclusions: High occupational stress and low job satisfaction were associated with high burnout, particularly in the emotional exhaustion and depersonalization dimensions. Low job satisfaction and high emotional exhaustion were associated with high turnover intention among employees. Personality traits, social support and coping style were also found to be associated with burnout.(J Occup Health 2013; 55: 458–467)

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Objectives: The aim of this study was to investigate the clinical characteristics of HAVS in a tropical environment in comparison with a temperate environment. Methods: We conducted a series medical examinations among the forestry, construction and automobile industry workers in Malaysia adopting the compulsory medical examination procedure used by Wakayama Medical University for Japanese vibratory tools workers. We matched the duration of vibration exposure and compared our results against the Japanese workers. We also compared the results of the Malaysian tree fellers against a group of symptomatic Japanese tree fellers diagnosed with HAVS. Results: Malaysian subjects reported a similar prevalence of finger tingling, numbness and dullness (Malaysian=25.0%, Japanese=21.5%, p=0.444) but had a lower finger skin temperature (FST) and higher vibrotactile perception threshold (VPT) values as compared with the Japanese workers. No white finger was reported in Malaysian subjects. The FST and VPT of the Malaysian tree fellers were at least as bad as the Japanese tree fellers despite a shorter duration (mean difference=20.12 years, 95%CI=14.50, 25.40) of vibration exposure. Conclusions: Although the vascular disorder does not manifest clinically in the tropical environment, the severity of HAVS can be as bad as in the temperate environment with predominantly neurological disorder. Hence, it is essential to formulate national legislation for the control of the occupational vibration exposure.(J Occup Health 2013; 55: 468–478)

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Objectives: While bedtime may influence circadian rhythms, potentially leading to depression, epidemiological data on this issue are limited. We cross-section-ally investigated the association between bedtime and depressive symptoms in Japanese workers, taking sleep duration into consideration. Methods: The participants were 1,197 workers who participated in a health survey during a periodic checkup and had no history of psychiatric disease. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) scale. Usual bedtime and wake time were inquired about using a self-administered questionnaire, and sleep duration was calculated based on the difference between these two values. Multiple logistic regression was used to estimate the odds ratio of depressive symptoms for bedtime or sleep duration categories. Results: Short sleep duration (<6 hours) was significantly associated with an increased prevalence of depressive symptoms. Late bedtime was also significantly associated with an increased prevalence of depressive symptoms (CES-D score of £19); the multi-variable-adjusted odds ratio of depressive symptoms for a bedtime of 1:00 or later versus 23:00 to 23:59 was 1.90 (95% confidence interval, 1.16–3.12). After additional adjustment for sleep duration, however, the association was largely attenuated (odds ratio, 1.17; 95% confidence interval, 0.66–2.06). Conclusions: Late bedtime was associated with increased prevalence of depressive symptoms, but this association could be largely accounted for by short sleep duration. Avoiding a late bedtime and obtaining a sufficient sleep duration may prevent depressive mood among workers.(J Occup Health 2013; 55: 479–486)

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Objectives: A prospective study was conducted to assess factors associated with risk of turnover among care workers in group homes (GHs) for elderly individuals with dementia. Methods: In January, 2010, 51 out of 238 GHs in Sapporo City responded to our request for participation in a survey. During February and March of 2010, 438 out of 700 care workers (62.6%) in the GHs returned a completed questionnaire to us. They were followed up with until March of 2012, and 395 subjects (90.1%) responded to our survey, which was conducted twice. Over the course of 2 years, 91 subjects left their jobs. Cox's proportional hazards model was used for analysis, adjusting for gender and age. Results: Less provision of social support by supervisors, colleagues, family or friends was significantly associated with increased risk of turnover. Financial aids for off-the-job training was marginally significantly associated with reduced risk of turnover. Longer duration of working for frail elderly care was significantly associated with decreased risk of turnover. Habitual smoking was significantly associated with increased risk of turnover. Conclusions: Social support in the workplace may be important to reduce the risk of turnover in care workers at GHs. Further prospective studies are required in other areas in Japan.(J Occup Health 2013; 55: 487–494)

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Objectives: We performed the current study to (1) understand the distribution of culturable airborne bacteria over a one-year monitoring period, (2) confirm places in stations where airborne bacteria are highly detected, (3) understand the factors that affect concentrations of airborne bacteria and (4) compare the distributions of airborne bacteria and fungi in railway stations in Japan. Methods: Measurements of airborne bacteria were taken at stations A and B located in Tokyo. Station A had under- and above-ground concourses and platforms, whereas station B had spaces only above-ground. Airborne bacteria at each measurement position were collected with an air sampler on plate count agar media. After cultivation of the sampled media, the number of bacteria colonies was counted on each media. Results: (1) Airborne bacteria were highly detected in the above-ground concourse in station A. Almost all the indoor-to-outdoor (I/O) ratios of concentrations of airborne bacteria in the above-ground concourse in station A were higher than one throughout the year and were especially high in summer. (2) The factor that affects the concentrations of airborne bacteria seems to be the number of railway customers, not humidity. (3) The characteristics of the distributions of airborne bacteria and fungi were different, even though they were sampled in the same stations on the same days. Conclusions: In the case of controlling indoor air quality of stations in the future, the locations in railway stations that would require control of indoor air quality differ between airborne bacteria or fungi, respectively.(J Occup Health 2013; 55: 495–502)

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Objectives: This study was conducted to assess the size characteristics of particulate matter (PM) generated during waste collection and sorting, and to assess the effect of the type of waste-handling activity on levels of coarse and fine PM. Methods: A portable aerosol spectrometer calibrated to 1.2 //min was used to monitor PM generated during four types of waste-handling activities. The types of PM measured included inhalable particulate matter (IPM), PM₁₀, respirable particulate matter (RPM), PM_2.5 and PM₁. Twenty-eight data sets with 3,071 subsets recorded every 6 sec were categorized according to occupational and environmen¬tal classifications, including type of waste-handling activity. An ANOVA was used to compare PM levels characterized by size. Significant variables with p-values <0.25 were included in a multiple regression model for predicting levels of each PM. Results: The average levels of PM₁₀ and PM_2.5 greatly exceeded the air-quality levels enforced by the Korean Ministry of the Environment. The highest PM_2.5 fine-particle levels monitored were during waste-transfer work, while the highest IPM and PM₁₀ coarse-particle levels monitored were during waste-sorting work. The type of waste-collection activity was the only factor that significantly affected both PM25 and IPM, accounting for 36% (p=0.0034) and 40% (p=0.0049), respectively, of the observed variations. None of the factors affected PM₁₀ or RPM levels. Conclusions: Waste-collection and Waste-transfer work may be associated with the generation of high levels of fine PM, which can be influenced by environ Workmental conditions such as traffic levels and the type of waste transport vehicle.(J Occup Health 2013; 55: 503–510)

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Objectives: The aim of this study was to assess the risk of developing bile duct cancer among workers in the other printing industry in comparison with workers in all industries in general. Methods: Prevalence of bile duct cancer was compared between workers in the printing industry and age-standardized controls in all other industries using the claims database of the Japan Health Insurance Association, which insures workers of small-medium sized employers of all industries. Results: Young (aged 30–49) male workers in the printing industry showed an elevated but insignificant standardized prevalence rate ratio (SPRR) for bile duct cancer in comparison with workers in all other industries (SPRR: 1.78; 95%CI: 0.63–5.00). The risk was higher for intrahepatic bile duct cancer but remained insignificant (SPRR: 3.03; 95%CI: 0.52–17.56). Conclusions: The sharply elevated risk of bile duct cancer observed among proof-printing workers of a printing factory in Osaka may not be generalizable to workers in the printing industry nationwide.(J Occup Health 2013; 55: 511–515)

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Objectives: Education on occupational health and safety (OHS) is not a compulsory part of the curriculum of general secondary schools (GSSs) in many countries. Adolescence is a formative period. Mainstreaming education in OHS into GSSs is necessary in order to initiate in students a risk prevention culture. We explored the feasibility of using a photo competition (PC) concerning health protection at work as a health education tool by assessing the degrees of relevant responses of students aged 13–18, teachers, parents and private enterprises and by identifying the types of work and hazards selected in 17 state and non-state GSSs of a Greek municipality. Methods: Following the mayor's decision to hold a PC, prizes were secured from 11 private donors, the PC was publicized widely, and presentations on OHS were delivered to students by an occupational physician and suitably instructed teachers; the students then took photos of identifiable work situations containing OHS hazards, with protection either present or absent. Photos were assessed by juries of the Municipality and of the European Centre for the Environment and Health of the WHO. Results: The 87 photos submitted revealed that students had an understanding of 15 types of OHS hazards, mainly knocks and blows (28.7%) and falls from heights (26.4%) but also of diseases (respiratory, back pain, hearing loss), in 28 types of non-school work, mostly in transport (12.6%) and construction (9.1%), and recognized measures for protection in 50.5% of photos. Conclusions: This PC concerning OHS in GSSs is the first reported in the literature, and it proved to be a feasible, extracurricular educational activity that requires increased teacher collaboration within the school curriculum.(J Occup Health 2013; 55: 516–519)

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