Objectives: Cerebrovascular and cardiovascular diseases (CCVDs) and mental disorders, including suicide, are prevalent among overworked individuals in Japan. The 2014 legislation regarding the prevention of overwork-related deaths and disorders has accelerated the research in this field and ultimately the implementation of preventive actions.

Methods: To understand the current problematic situations, the Research Center for Overwork-Related Disorders of the National Institute of Occupational Safety and Health, Japan, conducted analyses of compensated claims for overwork-related CCVDs and mental disorders that were recognized from January 2010 to March 2015.

Results: The majority of CCVD cases were the men in their 50s. Transport and postal activities was the highest risk industry. Cerebrovascular cases were higher than cardiovascular ones. Long working hours was the principal factor for CCVDs. The mental disorder cases comprised approximately 70% men and affected younger age groups (peak in the third decade) with various industries at risk. In men, there was an almost equal number of F3 (Mood [affective] disorders) and F4 (Neurotic, stress-related, and somatoform disorders) diagnoses according to the 10th revision of the International Classification of Diseases and Related Health Problems. A larger number of women were diagnosed to have F4. The mental disorder cases were associated not only with long working hours, but also with injuries and disasters as well as interpersonal conflict at work.

Conclusions: Multiple, simultaneous actions need to be made by employees, employers, researchers, and the authorities to achieve the goal of reducing the number of workers suffering from the overwork-related CCVDs and mental disorders.

Objective: Overwork-related cardiovascular and cerebrovascular disease (CVD) has a large impact on workers' rights and labor standards across East Asian countries. This article describes the background and impact of policies regarding overwork-related CVD in the past decades in Taiwan.

Methods: We reviewed government policies, guidelines, literature, and news addressing the problems and impact of policy changes to prevent and recognize overwork-related CVD since the 1990s, and collected data on overwork-related CVD cases in Taiwan from 2006 to 2017.

Results: In 2017, overwork-related CVD accounted for 13% of all cases of occupational diseases, but 79% of all deaths due to occupational diseases. Guidelines for recognizing overwork-related CVD cases were established in 1991; however, under-recognition exists in Taiwan due to poor exposure data on working hours and psychological factors and because most medical expenses are covered by the national health insurance system. Amendments on the guidelines, and stricter policies on overwork prevention were enforced following calls from labor unions, nongovernmental organizations, and legislators, but health disparities were introduced when certain industries were exempted from restrictions.

Conclusions: Long working hours and other work characteristics increase the risk of overwork-related CVD. By reviewing the changes in policy for preventing overwork and recognizing overwork-related disease, we identified the need for clearly defined guidance on evaluating overwork-related CVD, with specific criteria for working hours and other risk factors regarding work characteristics. National policies that lead to better working conditions and prevent overwork-related diseases must be developed.

Objectives: Recently, overwork-related disorders have become a major public health concern in Korea. This study investigated the current trends of working hours, causes of death in the working population, and compensation rates.

Methods: We reviewed the current trends of working hours, cause of death statistics in the working population, industrial accident compensation insurance (IACI) statistics, issues of compensation and prevention of work-related cerebro-cardio vascular diseases (CCVDs), mental disorders, and suicide.

Results: Although weekly working hours and the proportion of long working days have decreased, workers in small companies with fewer than five employees and those in the service sector continue to work long hours. The age standardized mortality due to CCVD and suicide was highest among those with managerial roles. In total, 589 CCVD cases and 104 mental disorder or suicide cases were compensated as occupational diseases in 2017. Between 2016 and 2017, 61% of 59 compensated suicides were related to overwork, specifically: long working hours, increased responsibility, or increased workload. The Korean government has introduced various policies to reduce working hours and to increase compensation approval rate for overwork-related CCVDs. Stakeholders have called for the introduction of independent laws to prevent overwork-related disorders, change organizational culture, and address the blind spots of the IACI Act and Labor Standard Act.

Conclusions: Prevention and compensation policies have improved working conditions in Korea, but there remains much to be done. This review significantly contributes to the understanding of the overall policies and research to prevent overwork-related disorders in Korea.

Objectives: In dental clinics, dental hygienists are exposed to aerosolized pathologic bacteria, which can be transmitted to the oral cavity via lip cosmetics. Accordingly, such contamination poses a consistent health risk among staffs. Our study examined the bacterial contamination of lip cosmetics used by dental hygienists while in a clinic setting.

Methods: Sixteen dental hygienists were surveyed regarding their job assignments and habits associated with lip cosmetic. Subsequently, microorganisms were analyzed in collected samples of the hygienists' lip cosmetics using colony-forming unit (CFU) assays, 16s-rDNA polymerase chain reaction, and DNA sequencing.

Results: Notably, 81.3% of the submitted lip cosmetic samples were contaminated, with bacterial CFUs ranging from undetectable to innumerable. Many samples (43.8%) exceeded the microbial limits of cosmetic contamination. Of the lip cosmetic used for more than 6 months, 60% exceeded the microbial limit. When wearing a mask every time, only one of the six samples exceeded the microbial limit. More frequent dental mask changing was associated with a lower likelihood that the cosmetic sample would exceed the microbial limit. No samples from hygienists who changed their masks four times a day exceeded the microbial limit, compared to 33.3% from hygienists who only changed the mask when it became wet. Most isolated bacteria were gram-positive, facultative anaerobic, asporogenic, and opportunistically pathogenic, and the most prevalent species were Staphylococcus aureus, Streptococcus salivarius, and Staphylococcus epidermidis.

Conclusion: Our findings indicate that dental staff, including dental hygienists, should exercise more careful workplace habits, particularly with regard to infection control and cosmetic use.

Objectives: To simplify the procedures to estimate biological occupational exposure limits (BOELs) by use of the ratio of geometric mean (GM) concentration of un-metabolized organic solvent in urine (U-GM) over GM organic solvent concentration in air (A-GM) (the [U-GM/A-GM] ratio).

Methods: Occupational Exposure Limits (OELs) and BOELs were cited from publications from the Japan Society of Occupational Health (JSOH) and the American Conference of Governmental Industrial Hygienists (ACGIH). Data on [U-GM/A-GM] and the SLOPE of exposure-excretion regression line were collected from published articles (men and women were treated separately). Correlation analysis and paired t test were employed as the method to examine statistical significances.

Results: Significant linear correlation was established between the SLOPE and the [U-GM/A-GM]. Thus, it was considered to be possible to calculate the SLOPE value from the [U-GM/A-GM]. Previously established equation of BOEL = SLOPE × OEL allowed to estimate BOEL values in 22 cases of data sets. The comparison of the estimated BOELs with the existing BOELs (JSOH's BOELs and ACGIH's BEIs) in terms of the ratio of [(estimated BOEL)/(existing BOEL)] showed that the ratios for the 22 cases probably distributed log-normally with a GM of 0.85, and the maximum was 5. Therefore, the estimated BOEL may be generally applicable in occupational health when BOEL remains yet to be established. In the worst case, the estimated BOEL may be five times greater than it should be. The recommended procedures for application of estimated BOEL values were described.

Conclusion: Simplified procedures for estimation of BOEL values are proposed.

Objectives: Although many studies have examined locomotive syndrome (LS) among elderly people, few studies have examined LS in young- and middle-aged adults. This study aimed to provide basic data on the epidemiological characteristics of LS, including in young- and middle-aged adults.

Method: We conducted a cross-sectional survey of a nonrandom sample of 852 adults aged 18-64 (678 males, 174 females) working in five companies in Japan, between December 2015 and February 2018. LS stage was determined using the criteria proposed by the Japanese Orthopaedic Association (JOA). LS stage 0 was defined as No-LS, and stages 1 and 2 were defined as LS. Multiple logistic regression analysis was used to investigate the independent relationship between LS and sociodemographic, smoking, alcohol drinking (AD), frequency of breakfast consumption (FBC), dietary variety score (DVS), and the University of California Los Angeles (UCLA) activity score after adjusting for age and sex.

Results: We found that 23.1% of participants were evaluated as LS, including 21.5% of males and 29.3% of females (P < 0.05). Participants aged ≥45 years exhibited higher rates of LS (males: 23.1%, females: 43.6%) compared with those aged <45 years (P < 0.05). Logistic regression analysis revealed that age, body mass index (BMI), AD, UCLA activity score, and FBC were also related to LS.

Conclusion: Education initiatives about LS should be targeted not only to elderly populations but also to young- and middle-aged adults in the workplace.

Objective: The purpose of this study was to investigate the effect of changes in overtime work hours on depressive symptoms among Japanese white-collar workers.

Methods: Participant data were collected from a company's annual mental health survey in June 2013 and June 2014. The participants comprised 922 workers who responded to the survey in both the years and had records of monthly working hours in the past 2 years. We obtained information on monthly working hours from personnel records from June 2012 to May 2014. Depressive symptoms were measured by the Brief Job Stress Questionnaire. Changes in overtime work hours were measured by creating a five-category variable for each monthly average of overtime work hours in the past year: (a) stable short, (b) decreased, (c) stable medium, (d) increased, and (e) stable long groups. Analysis of covariance was conducted to estimate the degree of depressive symptoms of each group for changes in overtime work hours.

Results: Significant differences among the groups were observed (F = 3.67, P = 0.006). In the Bonferroni multiple comparison test, significantly lower depressive symptoms were observed in the decreased group (point estimate = 9.56) compared to the stable short (10.76), stable medium (10.71), and increased groups (10.99). There was no significant difference between the decreased group and the stable long group (10.98).

Conclusions: A decrease in overtime work hours may prevent the deterioration of mental health. This knowledge could support the necessity of mental health measures through decreasing overtime work hours proposed by national policy in Japan.