Objectives: Several European studies showed that low organizational justice (i.e., procedural justice and interactional justice) was associated with major depressive disorders. In these studies, however, the diagnosis of major depressive disorders may be underestimated because they identified only individuals who visited a doctor and received a diagnosis. Moreover, these studies did not consider neurotic personality traits, which can affect the occurrence of major depressive disorders. The purpose of the present study was to investigate the cross-sectional association of organizational justice with major depressive episodes in the past 12 months more precisely in Japanese employees. Methods: A total of 425 males and 708 females from five branches of a manufacturing company in Japan completed self-administered questionnaires measuring organizational justice, other job stressors (i.e., job strain, social support at work, and effort-reward imbalance), neuroticism, and demographic characteristics. A web-based self-administered version of the computerized Composite International Diagnostic Interview Version 3.0 (CIDI 3.0) was used to assess major depressive episodes. Logistic regression analyses were conducted. Results: In the univariate analysis, low procedural justice and low interactional justice were significantly associated with major depressive episodes in the past 12 months. After adjusting for other job stressors and demographic characteristics, only the association of interactional justice remained significant. The moderating effect of neuroticism on the association of organizational justice with major depressive episodes in the past 12 months was not significant. Conclusions: Low interactional justice may be associated with major depressive disorders regardless or other job stressors or neurotic personality traits.(J Occup Health 2013; 55: 47–55)

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Objectives: The aim of the present study was to investigate whether PON2 gene polymorphisms (rs7493, rs12026, rs12704796, rs7785846 and rs7786401) are associated with susceptibility to noise-induced hearing loss (NIHL) in the Chinese population. Methods: A case-control study was conducted using 615 cases selected without any restriction in age or sex and 644 controls who were matched with the cases in terms of age, gender and the intensity and duration of exposure to noise. Information on these subjects was gathered by questionnaires that were administered through face-to-face interviews by trained interviewers. Results: We found that the rs7493 CG + GG genotype (OR=1.36, 95% CI, 1.08–1.72), rs12026 CG + GG genotype (OR=1.34, 95% CI, 1.06–1.70), rs7785846 CT + TT genotype (OR=1.36, 95% CI, 1.07–1.71) and rs7786401 GT + TT genotype (OR=1.33, 95% CI, 1.05–1.68) were risk factors for NIHL. Conclusions: PON2 gene polymorphisms may be associated with susceptibility to NIHL in the Chinese population.(J Occup Health 2013; 55: 56–65)

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Objectives: This study was a cross-sectional survey of Japanese workers regarding the relationship between touching the eyes or nose and susceptibility to URTI in workers. Methods: The survey respondents were 4,663 Japanese workers. Subjects were surveyed via a self-administered questionnaire regarding their susceptibility to URTI and how often they touched their eyes or nose. In addition, subjects were surveyed regarding their preventive behaviors and routine behaviors thought to be associated with URTIs. A multiple logistic regression model was used to assess the relationship between susceptibility to URTI and how often the eyes or nose are touched. Results: Responses from 3,663 individuals who answered the self-administered questionnaire were analyzed. There were 1,590 individuals (42.9%) with a “frequent incidence of URTIs”, defined as URTIs more than once a year. In terms of how often the eyes or nose are touched, the odds ratios (95% CI) for a frequent incidence of URTIs among the groups responding “sometimes” and “often” were 1.41 (1.21–1.63) and 1.96 (1.59–2.42) (trend test: p<0.001) compared with the groups responding “never” and “almost never”. Multivariate-adjusted odds ratios adjusted for confounding factors, i.e., behaviors to prevent URTIs, routine behaviors associated with URTIs, age, sex and BMI, were 1.33 (1.14–1.54) and 1.69 (1.36–2.09) (trend test: p<0.001). Conclusions: The present cross-sectional study indicates that susceptibility to URTI and how often the eyes or nose are touched are significantly associated in Japanese workers, independent of preventive behaviors and routine behaviors associated with URTIs.(J Occup Health 2013; 55: 66–73)

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Objective: The aim of this study was to assess the effect of a health promotion program with 2–3-month Internet or printed material support without a face-to-face intervention at a large-scale worksite. Methods: An uncontrolled intervention was conducted. In 2005, 22,429 employees underwent a health check-up and a lifestyle assessment. In 2006, 2,096 employees were recruited to participate in an intervention group (IntG), and the remaining 20,228 employees were allocated to a control group (ConG). After one-year follow-up, 1,888 employees in IntG and 15,474 employees in ConG were analyzed by Breslow's lifestyle index, overall prevalence of cardiovascular risk (OPCR) and 10% 10-year risk based on cardiovascular risk factors in 2007. Results: Breslow's lifestyle index (over 5 points) in IntG showed a higher OR (1.13 with a 95% CI of 1.01–1.26) than that in ConG. Compared with those with a poor lifestyle, the subjects who had maintained or improved their lifestyle showed a lower OPCR (OR 0.88, 95% CI 0.79–0.97; OR 0.84, 95% CI 0.74–0.95 [p for trend=0.003]) and 10% 10-year risk trend (OR 0.38, 95% CI 0.31–0.47; OR: 0.29, 0.22–0.37 [p for trend <0.001]). Conclusion: The present study showed that there was a modest lifestyle behavior change using a program without face-to-face contact. The employees who maintained and improved their lifestyle had a lower OPCR and 10% 10-year risk. Future study should increase the number of employees actively attempting to improve their lifestyles at a worksite.(J Occup Health 2013; 55: 74–83)

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Objectives: The aim of this study was to describe outdoor workers' sun-protective practices, workplace sun-safety culture and sun-protective equipment provision; investigate the association of demographic, personal and occupational factors with sun-protective practices; and identify potential strategies for improving workers’ sun protection. Methods: The present study used a clustered survey design with randomly identified employers in nine occupations. Employees provided questionnaire measures of demographics, personal characteristics (skin type, skin cancer risk perceptions, tanning attitudes, sun-exposure knowledge), personal occupational sun protection practices (exposure reduction, use of sun-protective clothing, sunscreen and shade), workplace sun-protective equipment provision and perceived workplace sun-safety culture. Summative scores were calculated for attitudes, knowledge, workplace provision and culture. A multivariable model was built with worker and workplace variables as plausible predictors of personal sun protection. Results: In this study, 1,061 workers (69% participation) from 112 workplaces provided sufficient information for analysis. Sex, age, prioritized ethnicity, education and risk perception differed significantly between occupational groups (p<0.001), as did workers' sun-protective practices and workplace sun-protection equipment provision and supportive culture. After adjustment, each one-point increase in Workplace Sun-safety Culture 2013Score (range 12 points) was associated with a 0.16 higher Personal Sun-Protection Score (p<0.001), and each one-point increase in Workplace Provision Score (range 4 points) was associated with a 0.14 higher score (p<0.001). Sun Protection Score was significantly associated with skin response to sun exposure (p<0.001), female sex (p=0.021), tanning attitudes (p=0.022) and occupation (p=0.049), but not ethnicity, age education, knowledge or skin cancer risk perception. Conclusions: Protective equipment provision and sun-protective workplace culture are promising components for the development of comprehensive programmes to improve outdoor workers' sun-protective practices.(J Occup Health 2013; 55: 84–97)

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Objective: The aim of this study was to examine the relationship between age and the lost-time workers' compensation claims in British Columbia, Canada, over three time periods (1997–98, 2001–02 and 2005–06). We examined if the relationship between age and risk of lost-time claims is consistent over time and for different nature of injury categories. Methods: Secondary analyses of lost-time workers' compensation claims combined with estimates of person-years of exposure generated from the Canadian Labour Force Survey were performed. Analyses examined the relationship between age and claim risk using sex-stratified regression models, adjusting for time period, occupational characteristics and whether the claimant was employed in the goods or service industry. Multiplicative interaction terms were used to examine if the relationship between age and lost-time claim risk changed over time. Seven separate regression models were generated to explore the variation in the effect of age across nature of injury groups. Results: We observed important differences in the relationship between age and risk of injury depending on the nature of injury examined. A negative relationship was observed between age and lost-time claims for open wounds, while a positive relationship was observed for traumatic injuries to bones, nerves and the spinal cord. We found no evidence that the relationship between age and risk of lost-time claims changed over time periods. Conclusions: The association between age and risk of lost-time claims depends on the nature of injury under investigation. We found no evidence that the relationship between age and overall lost-time claim risk has changed over time in British Columbia.(J Occup Health 2013; 55: 98–107)

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Objective: The objective of this study was to examine reliability and validity of the Japanese version of the Inventory of Violence and Psychological Harassment (IVAPT) (Pando, 2006), a 22-item measure of psychological harassment at work and presence and intensity of psychological violence widely used in Latin American countries. Methods: The IVAPT was translated into Japanese, and the translation was amended through a small pretest and a back-translation and finalized. A total of 1,810 out of 4,072 civil servants completed a questionnaire including the IVAPT. Results: Cronbach's alpha of the scale was 0.97 for psychological violence and 0.94 for psychological harassment at work. An exploratory factor analysis showed that the first factor explained 64.5% of the total variance. Data did not well fit to previously reported one- or three-factor structures. Psychological violence and harassment at work were more frequent among older respondents. Intensity of psychological violence was well concordant with other scales of workplace bullying, i.e., Leymann Inventory of Psychological Terrorization (LIPT) and Negative Acts Questionnaire-Revised (NAQ-R), and psychological harassment at work was well concordant with the NAQ-R. Conclusions: The Japanese version of the IVAPT showed high internal consistency reliability. While the first factor explained a large proportion of the variance, the IVAPT seems to have a unique factor structure in the Japanese sample. Concurrent validity of the IVAPT was supported by the comparison with the other scales. (J Occup Health 2013; 55: 108–119)

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Objectives: The purpose of this study was to examine the cause of an accidental death from acute poisoning resulting from exposure to a cleaner containing tetramethylammonium hydroxide (TMAH) and to consider measures to prevent future cases. Methods: The authors examined the details and the reason for the accidental death from acute poisoning based on the autopsy report. Results: The victim was a 39-year-old male researcher with 7 years of work experience employed by a surfactant production company. The accident occurred when he was conducting a field test of a newly developed cleaner, containing 8.75% TMAH solution. The researcher spilled the cleaner on his work clothes in the area of both the hands/arms and legs. He was unconscious when discovered. An autopsy found no damage or injury that could have resulted in death other than burns to 12% of his body, and the cause of death was found to be acute poisoning by TMAH. Discussion: TMAH is widely used in the electronics industry as a developer or cleaner. It is a dangerous material, causing neurotoxicity leading to respiratory failure by ganglion block that occurs through skin absorption, and no antidote has been developed yet. For this reason, it is best to completely prevent exposure by wearing proper personal protective equipment. Despite this fatal toxicity of TMAH, it is not classified in Korea as a “chemical requiring legal control”. For this reason, it is urgent to raise awareness of the toxic properties of TMAH to prevent additional cases of TMAH poisoning.(J Occup Health 2013; 55: 120–124)

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