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This study examined whether a fan-attached jacket (FAJ) may mitigate the heat strain in hot or humid environment.Nine healthy men engaged in 60-min sessions on a bicycle ergometer (4 metabolic equivalents [METs] workload) in hot-dry (40°C and 30% relative humidity) and warm-humid (30°C and 85% relative humidity) environments. Both are equivalent to an approximately 29°C wet-bulb globe temperature. The experiment was repeated-once wearing an ordinal jacket (control condition) and once wearing a long-sleeve FAJ that transfers ambient air at a flow rate of 12 L/s (FAJ condition)-in both environments.Increases in core temperatures in hot-dry environment were not statistically different between control and FAJ; however, that in the warm-humid environment were significantly different between control and FAJ (0.96 ± 0.10°C and 0.71 ± 0.11°C in rectal temperature, P .0001; and 0.94 ± 0.09°C and 0.61 ± 0.09°C in esophageal temperature, P .0001). Changes in heart rate were different between control and FAJ in both environments (62 ± 3 bpm and 47 ± 7 bpm, P .0001 in hot-dry environment; and 61 ± 3 bpm and 46 ± 5 bpm, P .0001 in the warm-humid environment) and decrease of %weight change was different in hot-dry environment (1.59 ± 0.12% and 1.25 ± 0.05%, P = .0039), but not in the warm-humid environment.Wearing a FAJ may mitigate heat strain both in hot or humid environments.

Background With the COVID‐19 pandemic, the idea of universal mask wearing to prevent infecting others when one becomes infected has prevailed among people. In general, any workplace is not exempt and workers are required to wear a mask while working at the sites. Objectives This study aims to integrate information to assist workers to select effective protectors for the prevention of droplet infection even at workplaces without occupational health personnel. Methods A total of 94 studies were included in this study: 91 studies were identified in MEDLINE, which was used for the literature search, and an additional three studies were identified from other information sources. The studies were checked to eliminate duplication and narrowed down to 31 based on the titles and abstracts. The contents of the 31 studies were read through and then 19 studies were extracted for careful reading. Results and Conclusions Regarding the protectors used at workplaces, it was suggested that (1) workers continue to use respiratory protectors as needed at sites where respiratory protectors such as an N95 respirator had to be used even before the spread of COVID‐19 and (2) wear surgical masks, multi‐layer cloth masks, or hybrid fabric masks made of several types of fabrics that are recommended in terms of preventing dissemination of droplets and protecting against inhalation of droplets, selected according to the working conditions, taking account of air permeability, breathability, and durability.

We examined whether blowing hot air above body temperature under work clothing may suppress core temperature. Nine Japanese men engaged in two 30-min bicycle ergometer sessions at a workload of 40% VO2max at 40 °C and 50% relative humidity. The experiment was conducted without wearing any cooling apparatus (CON), wearing a cooling vest that circulated 10.0 °C water (VEST), and wearing a fan-attached jacket that transferred ambient air underneath the jacket at a rate of 30 L/s (FAN). The VEST and FAN conditions suppressed the increases of rectal temperature (CON, VEST, FAN; 38.01 ± 0.19 °C, 37.72 ± 0.12 °C (p = 0.0076), 37.54 ± 0.19 °C (p = 0.0023), respectively), esophageal temperature (38.22 ± 0.30 °C, 37.55 ± 0.18 °C (p = 0.0039), 37.54 ± 0.21 °C (p = 0.0039), respectively), and heart rate (157.3 ± 9.8 bpm, 136.9 ± 8.9 bpm, (p = 0.0042), 137.5 ± 6.5 bpm (p = 0.0023), respectively). Two conditions also reduced the estimated amount of sweating and improved various subjective evaluations. Even in the 40 °C and 50% relative humidity environment, we may recommend wearing a fan-attached jacket because the heat dissipation through evaporation exceeded the heat convection from the hot ambient air.

Objectives To examine the thermoregulatory and fluid‐electrolyte responses of firefighters ingesting ice slurry and carbohydrate–electrolyte solutions before and after firefighting operations. Methods Twelve volunteer firefighters put on fireproof clothing and ingested 5 g/kg of beverage in an anteroom at 25°C and 50% relative humidity (RH; pre‐ingestion), and then performed 30 minutes of exercise on a cycle ergometer (at 125 W for 10 minutes and then 75 W for 20 minutes) in a room at 35℃ and 50% RH. The participants then returned to the anteroom, removed their fireproof clothing, ingested 20 g/kg of beverage (post‐ingestion), and rested for 90 minutes. Three combinations of pre‐ingestion and post‐ingestion beverages were provided: a 25℃ carbohydrate–electrolyte solution for both (CH condition); 25℃ water for both (W condition); and a −1.7℃ ice slurry pre‐exercise and 25℃ carbohydrate–electrolyte solution post‐exercise (ICE condition). Results The elevation of body temperature during exercise was lower in the ICE condition than in the other conditions. The sweat volume during exercise was lower in the ICE condition than in the other conditions. The serum sodium concentration and serum osmolality were lower in the W condition than in the CH condition. Conclusions The ingestion of ice slurry while firefighters were wearing fireproof clothing before exercise suppressed the elevation of body temperature during exercise. Moreover, the ingestion of carbohydrate–electrolyte solution by firefighters after exercise was useful for recovery from dehydration.

Rising global temperatures, coupled with decreasing access to clean drinking water, may enhance the effects of heat exposure to general and working populations across the globe. People working in jobs that require moderate or heavy manual labor in hot environments are at particular risk caused by the combined effect of exposures to high environmental heat and internal heat production. Exposures to heat can lead to a range of clinical health effects such as fatigue, exhaustion, heat syncope, fainting, heat stroke or even death. Furthermore, heat-related physical exhaustion leads to a reduction of the worker's ability to work with consequent productivity losses that may cause substantial economic losses for the businesses. The result of such continuous heat exposures, manual work and repeated dehydration are also known to cause acute kidney injuries that can further develop into chronic kidney diseases. With the predicted rise in temperatures due to climate change, the health effects for the working population are expected to become worse without appropriate interventions. With this background, the present review focuses on the heat-related health illnesses with special attention to kidney disease among workers engaged in manual physical labor in different occupational sectors.

none 13 si Among other purposes, companies and regulatory agencies from around the world often adopt International Standard Organization (ISO) standards to determine acceptable practices, equipment and criteria for preventing occupational injuries and illnesses. ISO standards are based on a consensus among individuals who participate in the process. This discussion paper examines the scientific process for the development of several ISO standards on biomechanical factors, comparing it with processes used by other professional organizations, including scientific committees working on the development of clinical guidelines. While the ISO process has value, it also has clear limitations when it comes to developing occupational health and safety standards that should be based on scientific principles. open Armstrong, Tom J; Burdorf, Alex; Descatha, Alexis; Farioli, Andrea; Graf, Maggie; Horie, Seichi; Marras, William S; Potvin, Jim R; Rempel, David; Spatari, Giovanna; Takala, Esa-Pekka; Verbeek, Jos; Violante, Francesco S Armstrong, Tom J; Burdorf, Alex; Descatha, Alexis; Farioli, Andrea; Graf, Maggie; Horie, Seichi; Marras, William S; Potvin, Jim R; Rempel, David; Spatari, Giovanna; Takala, Esa-Pekka; Verbeek, Jos; Violante, Francesco S

Background Mesothelioma is increasingly recognised as a global health issue and the assessment of its global burden is warranted. Objectives To descriptively analyse national mortality data and to use reported and estimated data to calculate the global burden of mesothelioma deaths. Methods For the study period of 1994 to 2014, we grouped 230 countries into 59 countries with quality mesothelioma mortality data suitable to be used for reference rates, 45 countries with poor quality data and 126 countries with no data, based on the availability of data in the WHO Mortality Database. To estimate global deaths, we extrapolated the gender-specific and age-specific mortality rates of the countries with quality data to all other countries. Results The global numbers and rates of mesothelioma deaths have increased over time. The 59 countries with quality data recorded 15 011 mesothelioma deaths per year over the 3 most recent years with available data (equivalent to 9.9 deaths per million per year). From these reference data, we extrapolated the global mesothelioma deaths to be 38 400 per year, based on extrapolations for asbestos use. Conclusions Although the validity of our extrapolation method depends on the adequate identification of quality mesothelioma data and appropriate adjustment for other variables, our estimates can be updated, refined and verified because they are based on commonly accessible data and are derived using a straightforward algorithm. Our estimates are within the range of previously reported values but higher than the most recently reported values.

We aimed to develop a practical method to estimate oesophageal temperature by measuring multi-locational auditory canal temperatures. This method can be applied to prevent heatstroke by simultaneously and continuously monitoring the core temperatures of people working under hot environments. We asked 11 healthy male volunteers to exercise, generating 80 W for 45 min in a climatic chamber set at 24, 32 and 40 °C, at 50% relative humidity. We also exposed the participants to radiation at 32 °C. We continuously measured temperatures at the oesophagus, rectum and three different locations along the external auditory canal. We developed equations for estimating oesophageal temperatures from auditory canal temperatures and compared their fitness and errors. The rectal temperature increased or decreased faster than oesophageal temperature at the start or end of exercise in all conditions. Estimated temperature showed good similarity with oesophageal temperature, and the square of the correlation coefficient of the best fitting model reached 0.904. We observed intermediate values between rectal and oesophageal temperatures during the rest phase. Even under the condition with radiation, estimated oesophageal temperature demonstrated concordant movement with oesophageal temperature at around 0.1 °C overestimation. Our method measured temperatures at three different locations along the external auditory canal. We confirmed that the approach can credibly estimate the oesophageal temperature from 24 to 40 °C for people performing exercise in the same place in a windless environment.

The use of Information and Communication Technology devices (ICT) has spread globally; therefore, increasing exposure to these display devices is an important health issue in the workplace. The association between ocular axial length (AL) elongation and ICT use was investigated among 7334 middle-aged Japanese male workers. Detailed ICT use information was obtained using a self-administered questionnaire. The high AL group was defined as the group with AL above the 75th percentile for each 5-year age interval. Logistic analysis showed that the odds ratio (OR) for the high AL group of >8 hours/day, adjusted for potent confounding factors, was significantly elevated relative to

In Japan, compensable occupational diseases are officially listed in Appended Tables 1 and 2 of Ordinance for Enforcement of the Labor Standards Act. The category No. 3 (diseases caused by work with extreme physical tension) includes subcategories of (b): Low back pain due to work to handle heavy objects, those done in unnatural postures or others which involve excessive tension to low back, and (d): musculoskeletal disorders of the back of the head, neck, shoulder girdle, upper arm, forearm, or fingers due to work which require repeated input into a computer or other operation involving excessive tension on the upper limbs. Local labour standard bureau is in charge of judging the work-relatedness.

We thank Drs. Colombini and Occhipinti for their personal reply to our Discussion Paper (1, 2). We share the overall goal of preventing workplace injuries and welcome a discussion of the ISO process on workplace ergonomics standards; this was the primary aim of the Discussion Paper. We hope that other members of the relevant ISO working groups will also participate in the discussion. However, Drs. Colombini and Occipinti misinterpret our paper. Our aim was not to “addresses the scientific basis of ISO standards on biomechanical risk factors and more specifically the OCRA methodology”. The purpose was to point out that “while the ISO process has value, it has also clear limitations when it comes to developing occupational health and safety standards that should be based on scientific principles”. It is true that our paper discussed the OCRA method, but only as an example, in a single paragraph. We noted that the OCRA method was promoted as the preferred method by the ISO working group even though there were other risk assessment methods which, at the time (and currently), were at least as scientifically valid (3). The discovery that, while on the ISO working group, Drs. Colombini and Occipinti elevated the risk assessment method that they developed (OCRA) over the other methods, demonstrates one of several limitations of the ISO process, namely, the lack of attention to conflict of interest. Finally, we would like to draw attention to the note by Drs. Colombini and Occhipinti that “the ISO standards in question were actually developed by the working group, as mandated by ISO, over the period 2000‒2004”. This long-elapsed time, without an update to the standard, should be a concern for all scientists given the large quantity of quality scientific literature published since then (eg, 3‒6). Fourteen years is well beyond what is recommended in the ISO guidelines. References 1. Colombini D, Occhipinti E. Scientific basis of the OCRA method for risk assessment of biomechanical overload of the upper limb, as preferred method in ISO standards on biomechanical risk factors. Scand J Work Environ Health ‒ online first. https://doi.org.10.5271/sjweh.3746 2. Armstrong T J, Burdorf I A, Descatha A, Farioli A, Graf M, Horie S, Marras W S, Potvin J R, Rempel D, Spatari G, Takala E P, Verbeek J, Violante FS. Scientific basis of ISO standards on biomechanical risk factors. Scand J Work Environ Health ‒ online first. https://doi.org/10.5271/sjweh.3718 3. Takala EP, Pehkonen I, Forsman M, Hansson GA, Mathiassen SE, Neumann WP, Sjogaard G, Veiersted KB, Westgaard RH, Winkel J. Systematic evaluation of observational methods assessing biomechanical exposures at work. Scand J Work Environ Health. 2010;36:3-24. https://doi.org/10.5271/sjweh.2876 4. Paulsen R, Gallu T, Gilkey D, Reiser R, Murgia L, Rosecrance J. The inter-rater reliability of Strain Index and OCRA Checklist task assessments in cheese processing. Applied Ergonomics. 2015; 51,199-204. https://doi.org/10.1016/j.apergo.2015.04.019 5. Kapellusch JM, Gerr FE, Malloy EJ, Garg A, Harris-Adamson C, Bao SS, Burt SE, Dale AM, Eisen EA, Evanoff BA, Hegmann KT, Silverstein BA, Theise MS, Rempel DM. Exposure-response relationships for the ACGIH threshold limit value for hand-activity level: results from a pooled data study of carpal tunnel syndrome. Scand J Work Environ Health. 2014;40:610-20. https://doi.org/10.5271/sjweh.3456 6. Violante FS, Farioli A, Graziosi F, Marinelli F, Curti S, Armstrong TJ, Mattioli S, Bonfiglioli R. Carpal tunnel syndrome and manual work: the OCTOPUS cohort, results of a ten-year longitudinal study. Scand J Work Environ Health. 2016;42:280-90. https://doi.org/10.5271/sjweh.3566

In Japan, compensable occupational diseases are officially listed in Appended table 1 and 2 of Ordinance for Enforcement of the Labour Standards Act. The category No. 3 (diseases caused by work with extreme physical tension) includes a subcategory of (d): musculoskeletal disorders of the back of the head, neck, shoulder girdle, upper arm, forearm, or fingers due to work which require repeated input into a computer or other operation involving excessive tension on the upper limbs. Local labour standard bureau is in charge of judging the work-relatedness. The detailed criterion was first published as a notice from the Labour Standard Bureau, Ministry of Labour on Feb 5, 1975, as ‘Judgment criterion for work-relatedness of upper extremity disorders from keypunching work’ (Notification No. 59, 1975) and revised on Feb 3, 1997, as ‘Judgment criterion for work-relatedness of diseases from upper extremity work’ (Notification No. 65, 1997). Target diseases of the criterion include humeral epicondylitis, cubital tunnel syndrome, supinator syndrome, wrist tendonitis, carpal tunnel syndrome and cervico-omo-brachial syndrome (COBS; nonspecific symptoms of neck, shoulder and upper extremity). Three indispensable conditions of the required exposure for determining work-relatedness are: long (≥6 months in general) and heavy workload to the upper extremity, excessive (≥10% increase, ≥20% increase/day for 10 days/months or ≥20% increase/hour for ≥1/3 hours/day) workload for 3 months preceding symptoms and reasonable time course. The criterion requires careful and comprehensive judgment of the work-relatedness of individual cases referring to the working environment, heteronomous and restrictive nature of the work, their age, physical strength, life style at home, etc. It recommends avoiding diagnosing as COBS; however, it still allows use of COBS when the specified diagnoses are difficult. According to the workers’ compensation statistics in 2016, there were 153 cases of upper extremity diseases out of 7361 cases of occupational diseases in total with 4 or more lost work-days.

Introduction In Japan, the prevention of fatal heat strokes at work has become more important along with the global warming. Methods This research introduces the transition of methods to prevent heat stroke at workplaces in Japan within the latest 20 years. Results The number of fatal heat stroke at work in Japan had been less than 20 until 1993; however, it exceeded 20 in 1994 and in 1995, consecutively because of the heat wave attack during summer. Therefore, in 1996, the guideline on prevention of heat stroke at work was formulated and publicised by the Labour Standard Bureau, Ministry of Health, Labour and Welfare. It advocated fundamental methods for the prevention of heat stroke such as working environment management, work management, health management and occupational health education at workplaces exposed to heat stress. Besides, the government started to announce the number of compensated cases of heat strokes every year. In 2005, another guideline was issued advocating the measurement of WBGT at the workplaces and the utilisation of the value for appropriate countermeasures. In 2009, the first guideline was totally revised by adding many new contents: the utilisation of WBGT, the promotion of heat acclimation, the method of desirable water and salt intake, the consideration for vulnerable persons with underlying diseases and the management of daily physical conditions. In addition, due to the impact of the Great East Japan Earthquake in 2011, nuclear power generation in Japan was temporarily suspended, and the need for the development of measures against heat stroke that did not use electric power as much as possible had increased, from the viewpoint of energy saving. Therefore, sports drinks and oral rehydration, salt candy, cool best to cool the body, clothing of quick-drying/cool feeling materials, etc. have started to be sold and widely spread. Discussion Although the motivation for the prevention of heat strokes have spread rapidly during the last 20 years, according to the guidelines formulated by the government, the number of mortality often exceeds 20, including 47 in the historically worst year of 2010. While easy and inexpensive devices to prevent heat stroke such as nutritional supplements and special wears have become widespread, it is important to verify its effectiveness in an objective manner and to standardise the definition of devices able to cool down the body heat.

Introduction In Japan, people scoring 8 to 14 points by the Alcohol Use Disorder Identification Test (AUDIT) are recommended to receive the health guidance to avoid risk of alcoholism and those scoring 15 or higher are considered to need the specialised medical treatment of their problem drinking. There are many risk factors of alcohol related disorders among workers such as a managerial role, a shift work, smoking (Brinkman index 400 or more) and the result of the alcohol patch test; however, they have not been verified by the scores of AUDIT. Methods We conducted a survey using a self-administered questionnaire including AUDIT among 2915 employees of a manufacturing worksite who received a periodic medical examination in fiscal 2015. We used binomial logistic regression analysis to explore the risk factors to predict development of the condition scoring 15+points by AUDIT among various independent variables: age, managerial position, shift work, smoking, the result of the alcohol patch test to screen variant aldehyde dehydrogenase. Statistically significant level was set at p Result We analysed the data obtained from 2299 male employees under 60-year-old who answered to all questions, and found 183 workers (8.0%) scored 15+points by AUDIT. The significantly increased risks were found with managerial roles (OR: 1.74), with negative result of the alcohol patch tests (OR: 6.87) and with smoking habit (OR: 1.71); however, the significant relationship was not found with shift work. Discussion Our result may reflect the tendency that managers are likely to excuse their drinking habit as a means of business practice and communication, and people with high social standing can afford to drink. There may be a synergistic effect between drinking and smoking. Occupational health should be more cautious to prevent problem drinking based on personal and social characteristics.

Introduction Prolonged walking, sitting and standing were thought a risk factor of low back pain. We wanted to measure the prolonged walking, sitting and standing time among workers at the workplace to evaluate their low back pain. But it was difficult to measure these times. Foot planter pressure shifts according to the walking, sitting and standing modes. We handmade an insole typed foot planter pressure data logger and algorithm to presume the walking, sitting and standing time from the foot planter pressure data. Methods The foot planter pressure data logger was composed by two resistive pressure sensors, a microcontroller, a micro SD card memory and a lithium ion battery. The foot planter pressure data downloaded to a personal computer and analysed to presume walking, sitting and standing time using visual basic software. We validated the presumption time of walking, sitting and standing from 10 min real activity time of running, walking, static sitting, dynamic sitting, static standing, dynamic standing, and taking off the shoe, respectively. This protocol did three times by one parson. Results Concordance rate between the presumption time and the real activity time was running 83%±12%, walking 100%±0%, static sitting 96%±6%, dynamic sitting 100%±0%, static standing 93%±6%, dynamic standing 73%±38%, and taking off the shoe 97%±6%, respectively. To join the running and walking time to the walking time, the static and dynamic sitting time to the sitting time, the static and dynamic standing time to the standing time, the concordance rate was up to 98.5%±3%, 100.2%±3%, and 100.2%±7%, respectively. Conclusion The insole typed foot planter pressure data logger had almost 98% concordance rate between the presumption time and the real activity time of walking, sitting and standing. We could measure the walking, sitting and standing time of workers during their working time.

Introduction Karoshi (death from overwork) has been a difficult challenge in Japanese society for a long time. In July 2015, the cabinet of Japan approved a guideline required by the Act on Promotion of Preventive Measures against Karoshi and other Overwork. In response to the guideline, the University of Occupational and Environmental Health, Japan (UOEH) launched a project to develop human resources to prevent harmful health effects from overwork. This report summarises the programmes for human resources development provided by UOEH Methods The Centre for Stress-related Disease Control and Prevention (CSDC) was established at UOEH to perform development of human resources in April 2016. At first, the CSDC created a special training programme for 35 experienced occupational physicians who are certificated by the Japan Society for Occupational Health, to improve their understandings of health issues arising from overwork. Those physicians who completed this programme were appointed as on-site lecturers of UOEH. Then, the CSDC delivered various seminars together with the on-site lecturers, targeting occupational physicians, nurses, hygienists and human resource personnel around Japan to let them prevent and overcome the adverse health effects from overwork. Questionnaires were provided to the participants in the seminars for their improvement. Results All except for one occupational physicians completed the special training programme in 2016. Regarding the seminars, the total number of participants by July 2017 was counted as 355. All together 69% of the participants responded to the questionnaires and 93.4% of the responders were satisfied with the seminars. Furthermore, 86.7% of them thought the skills and knowledge provided through the seminars were applicable to their work. Conclusion The CSDC, an organisation at UOEH, was established to rise on-site lecturers and to deliver seminars with them for the prevention of the adverse health effects from overwork.

Introduction Inhalation resistance of respirators may induce additional burden for workers breathing. Powered air-purifying respirators (PAPR) are considered to reduce this burden by assisting inhalation with powered fan. While there are mainly two types of blower system; breath response type and constant air flow type, no study has been conducted to clarify the difference of their physiological effects as far as we searched. We conducted this study to elucidate the physiological effects of wearing different types of PAPR by measuring physiological parameters and the microclimate inside the PAPRs. Methods Eight healthy males participated in the study. They took a 40 minutes-exercise with ergometer at 20, 30, 40% and 50% VO 2 max while wearing three types of masks; half mask facepiece with breath response type (BR–PAPR), half mask facepiece with constant air flow type (CF–PAPR) and mask of expiration gas analyzer (control). We continuously measured their auditory canal temperature ( t ac ), heart rate (HR) and SpO 2 . We also measured the microclimates (temperature, humidity, O 2 , CO 2 ) inside the two PAPRs. Their subjective symptoms were also surveyed. Statistical analysis was performed by IBM SPSS Statistics22.0. Result There were few differences in the trend of t ac , HR and SpO 2 among the masks. SpO 2 gradually declined but remained within normal level. The temperature and humidity inside masks were higher in BR-PAPR. During inhalation period, the proportion of time which O 2 concentration became lower than 18% or which CO 2 concentration exceeds 3% inside the respirators were lower in CF-PAPR. The participants’ perception of hotness or humidity coincided with the microclimates. Discussion BR-PAPR is known for the better durability of battery compared with CF-PAPR. There were few differences in physiological parameters among those respirators. However, with respect to the microclimate inside respirators, CF-PAPR was better than the BR-PAPR, hence it may affect comfort of the workers.

Introduction Primary causes of heat-related illness (HRI) at work are: extreme heat and humidity, heavy work load, continuous exertion and infrequent rest, clothes with poor vapor–permeability, and personal health condition. Empirical research has not been performed to investigate the effect of underlying health problems to HRI. Methods A case-control study was performed by asking occupational health staffs to report all HRI cases occurred at their workplaces in 2015 and 2016. One co-worker control of the same gender at the closest in age was also reported for each case. Target population included: 26 large manufacturing factories, 15 major construction companies, all traffic guard companies in Japan, and a fire stations in Kitakyushu city. Their results of the periodic health examination were collected to evaluate the underlying health problems of obesity (BMI >25), impaired glucose tolerance, IGT (HbA1c≥6.5%, fast blood sugar ≥126 mg/dL, and/or casual blood sugar ≥200 mg/dL), high blood pressure, HBP (≥140/90 mmHg), and dyslipidemia (LDL-C ≥140 mg/dL, HDL-C Results Overall incidence rate of HRI at the examined workplaces was 0.065% (114 cases/1 76 094 person-year). A total of 102 pairs (n=204) could be compared. Cases showed higher BMI (p=0.046) and visceral circumference (p=0.045). Cases and controls included 12 and 2 persons with IGT, respectively (p=0.005). Multiple logistic regression analysis revealed increase of HbA1c elevated the risk of developing HRI (OR 16.76 [95% CI: 2.44 to 165.5], p=0.0014), whereas LDL-cholesterol showed protective effect (OR 0.97 [0.95–0.99], p Conclusion Significantly elevated risk of developing heat-related illness was observed among workers with IGT. Impaired endothelium-dependent vasodilatation among workers with IGT may decrease heat dissipation by conduction, convection, radiation, and sweat evaporation and may pose a risk to develop HRI.

Introduction Workers often drink alcohol for releasing stress. However, many reports show that heavy drinking is a risk of depression. Some mentioned the influence of not only the amount of drinking alcohol but also the wrong way of using alcohol like binge drinking should be examined. Alcohol Use Disorders Identification Test (AUDIT) can evaluate the way of one’s using alcohol and the amount of drinking. Thus it is able to examine the more accurate influence of alcohol for depression. In this study, we analysed the relationship between AUDIT score and depression from work-related stress by The Brief Job Stress Questionnaire (BJSQ). Methods 4799 workers in a manufacturing company participated in this study. We analysed the data obtained from 4709 male employees without any missing value in logistic analysis and categorised depression as the dependent variable (13:high score group, 12≧: low score group), AUDIT score (0–14: group I, 15–19: group II, 20-: group III), job status (managerial or not), overtime work (per month, 80 hours: severe), quantitative overload (high/middle/low), qualitative overload (high/middle/low), stress with interpersonal relationships (high/middle/low), and job control (high/middle/low), as independent variables. Results Depression tended to be higher in group II of AUDIT(OR: 1.40, 95% CI: 0.99 to 1.96, p=0.54) and group III (OR: 2.45, 95% CI: 1.36 to 4.42, p=0.003). About overtime-work, the severe group was more depressive than mild group (OR: 2.38, 95% CI: 1.45 to 3.90, p Conclusion Higher AUDIT score seemed to show higher risk of developing depression. The wrong way of using alcohol may be an exacerbating factor of depression. We should be careful to drinking on the purpose of releasing stress.

Introduction It is known that heat stroke is likely to occur when workers are not acclimatised to heat. The purpose of this study is to clarify if the physiological responses of heat acclimatisation are different by the seasonal difference of the temperature in living environment. Methods Four healthy males in twenties repeated a 20 minutes-exercise on an ergometer at 40% VO 2 max for three times in three different thermal environments in the artificial climate room controlled at 28°C, then elevated to 34°C and finally to 40°C where relative humidity was fixed at 50%. Each exercise was followed by 20 minutes-rest period kept seated in the adjunct room at 24°C. They were asked to exercise consecutively for five days. This series of intervention was repeated during summer and winter seasons. We continuously measured their auditory canal temperature ( t ac ) and heart rate (HR). We also examined their sweat Na + and K + concentration and estimated their sweat volume from the body weight loss. Result The observed t ac and HR at the end of the exercise were generally higher in winter compared to summer. The sweat volume gradually increased for five days and the volume during the first exercise period at 28°C was larger in summer; however, the amount of increase was larger in winter. The sweat Na + concentration positively correlated with sweat volume and we observed smaller elevation of Na + concentration along with the increase of sweat volume in summer. Discussion The lower t ac and HR, earlier sweating, and smaller elevation of Na + concentration during heat acclimatisation in summer seem to be caused by the different thermal condition of living environment

Introduction SAS is known to cause drowsiness and lack of concentration at work and poses a serious job-fitness risk as a train driver. E company launched the initial screening program in 2003 using Epworth Sleepiness Scale (ESS) and induced pulse oximetry in 2007, and examin all train drivers every three years. Methods Ased on ESS and pulse oximetry the detailed examination using sleeping polysomnography (PSG). Crews who need medical treatment such as continuous positive airway pressure (CPAP) were subject to work restrictions until the improvement was confirmed. Results According to the statistics for 9 years until October 2016, 5500 crews examined 151 crews were subject to work restrictions. After treatment, more than 90% of the cases have recovered their AHI to less than 30% of previous level, and all drivers successfully returned to their original jobs in about 2 weeks. Discussions Arger proportion of SAS patients (2.7%) than average Japanese population (1.7%, Guidelines for Diagnosis and Treatment of Sleep Disordered Breathing in Cardiovascular Disease), company is still experiencing false negative cases improve the drivenvironment to prevent daytime drowsiness and educations for crew members.

Background: The transcription factor, zinc finger protein 143 (ZNF143), positively regulates many cell-cycle-related genes. The ZNF143 would show high expression of multiple solid tumours related closely to cancer cell growth, similar to the widely accepted Ki67 (MIB-1) protein, but the underlying mechanisms for ZNF143 remain unclear. We investigated the association of ZNF143 expression with clinicopathological features and prognoses of patients with lung adenocarcinoma. Methods: Expressions of ZNF143 and MIB-1 were immunohistochemically analysed in 183 paraffin-embedded tumour samples of patients with lung adenocarcinoma. The ZNF143 expression was considered to be strong when >30% of the cancer cells demonstrated positive staining. Results: Strong ZNF143+ expression showed a significantly close relationship to pathologically moderate to poor differentiation and highly invasive characteristics. The ZNF143 positivity potentially induced cell growth of lung adenocarcinoma, correlated significantly with high MIB-1 labelling index (⩾10%). Univariate and multivariate analyses demonstrated that both strong ZNF143+ and the high MIB-1 index group have only and significantly worse survival rates. Conclusions: The combination of strong ZNF143 expression and high MIB-1 index potentially predicts high proliferating activity and poor prognosis in patients with lung adenocarcinoma, and may offer a therapeutic target against ZNF143.

Prehypertension is a known risk factor for hypertension in individuals aged less than 20 or more than 35 years, but no large studies have investigated this risk in individuals aged 20-34 years. This study investigated progression to hypertension in nonhypertensive individuals aged 20-34 years and compared this group with individuals aged 35-64 years.A total of 12,639 nonhypertensive individuals aged 20-64 years were followed from 1999 to 2008. Hazard ratios for progression to hypertension were calculated for men and women according to three blood pressure (BP) categories (optimal BP:120/80 mmHg; normal BP: 120-129/80-84 mmHg; high-normal BP: 130-139/85-89 mmHg) and three age groups (20-34, 35-49 and 50-64 years).Progression to hypertension occurred in 4617 individuals (36.5%). The risk of progression to hypertension increased significantly with increasing baseline BP category in men and women in all age groups. The association between baseline BP and progression to hypertension was stronger in the group aged 20-34 years than in the older age groups, especially in men.The results of this study confirm that normal or high-normal BP increases the risk of progression to hypertension in individuals aged 20-34 years. In men, the association between baseline BP and progression to hypertension is stronger in this age group than in older age groups. Health providers should be aware that normal or high-normal BP is a risk factor for progression to hypertension even in individuals aged 20-34 years.

Hearing conservation of elderly workers is important to keep their quality of life and to prevent occupational accidents. We performed this study to measure the age difference of hearing acuity in noisy environment. Subjects were total of 16 elderly (45 years old or more) and 21 healthy young people (35 years old or less). The two-syllable speech intelligibility with/without earplugs, with/without exposure to pink noises at 80 dB(A), 85 dB(A), and 90 dB(A) were measured in an anechoic room. For both age groups, the differences between the speech level required for 90% intelligibility and the noise level were nearly constant when the subjects wore ear plugs in noisy environment. Wearing ear plugs will be beneficial not only to protect hearing acuity but also to converse easily while wearing earplugs. However, special attention must be paid to talk loudly while wearing earplugs considering the Lombard effect.

Workers working in hot or cold environments are at risk for heat stroke and hypothermia. In Japan, 1718 people including 47 workers died of heat stroke in 2010 (Ministry of Health Labour and Welfare, Japan 2011). While the American Conference of Governmental Industrial Hygienists (ACGIH) recommendation lists the abnormal core temperature of workers as a criterion for halting work, no method has been established for reliably measuring core temperatures at workplaces. ISO 9886 (Ergonomics-evaluation of thermal strain by physiological measurements. ISO copyright office, Geneva, pp 3-14; 2004) recognizes urine temperature as an index of core temperature only at normal temperature. In this study we ascertained whether or not urine temperature could serve as an index for core temperature at temperatures above and below the ISO range. We measured urine temperature of 31 subjects (29.8 ± 11.9 years) using a thermocouple sensor placed in the toilet bowl at ambient temperature settings of 40, 20, and 5˚C, and compared them with rectal temperature. At all ambient temperature settings, urine temperature correlated closely with rectal temperature exhibiting small mean bias. Urine temperature changed in a synchronized manner with rectal temperature at 40˚C. A Bland and Altman analysis showed that the limits of agreement (mean bias ± 2SD) between rectal and urine temperatures were -0.39 to +0.15˚C at 40˚C (95%CI -0.44 to +0.20˚C) and -0.79 to +0.29˚C at 5˚C (-0.89 to +0.39˚C). Hence, urine temperature as measured by the present method is a practical surrogate index for rectal temperature and represents a highly reliable biological monitoring index for assessing hot and cold stresses of workers at actual workplaces.

We estimated the level of noise that telephone operators were exposed to through headphones by a two-step method using an artificial ear technique and a manikin technique. In the artificial ear technique, the sound pressure level (Leq) of the total work hours was 81.5 dB, whereas the Leq of the total duration of phone calls was 89.3 dB. Therefore, we conducted a more accurate measurement by the manikin technique (ISO11904-2). By this method, we could simulate the headphone-wearing condition of the workers and convert the measurements to a diffuse-field related L(Aeq). By this manikin technique, the corrected L(Aeq) of the total work hours was 68.3 dB, whereas the corrected L(Aeq) of the total duration of call was 76.6 dB, which was below the standard of the Occupational Exposure Limits of the Japan Society of Occupational Health. We confirmed that in a workplace where the background noise is low (51.3 dBA), a good signal-noise ratio is maintained so that operators don't have to listen to loud sounds through headphones. Neither the gender nor the type of the telephone equipment of the callers affected the sound pressure levels.

We reviewed the effect of lunar dust (regolith) on humans by the combination of the hazard/exposure of regolith and microgravity of the moon. With regard to the physicochemical properties of lunar dust, the hazard-related factors are its components, fibrous materials and nanoparticles. Animal exposure studies have been performed using a simulant of lunar dust, and it was speculated that the harmful effects of the simulant lies between those of crystalline silica and titanium dioxide. Fibrous materials may not have a low solubility judging from their components. The nanoparticles in lunar dust may have harmful potentials from the view of the components. As for exposure to regolith, there is a possibility that particles larger than ones in earth (1 gravity) are respirable. In microgravity, 1) the deposition of particles of less than 1 µm in diameter in the human lung did not decrease, 2) the functions of macrophages including phagocytosis were suppressed, 3) pulmonary inflammation was changed. These data on hazard/exposure and microgravity suggest that fine and ultrafine particles in regolith may have potential hazards and risks for humans.

Background: It remains unclear how much coronary risk factors contribute to the prediction of myocardial infarction among Japanese populations.Methods and results: A nested case-control study of Japanese male workers aged 35 to 65 years was conducted between 1997 and 2000 in the Morbidity of Myocardial Infarction Multicenter Study in Japan (3M Study). Two hundred four myocardial infarctions were identified and two controls per case were selected by matching for age. We calculated odds ratios using a conditional logistic regression model, and constructed risk predictive models for the risk of myocardial infarction using coronary risk factors. The multivariable odds ratios (95 percent confidence intervals) of myocardial infarction were 2.02 (1.29-3.16) for high blood pressure, 2.33 (1.51-3.59) for high LDL-cholesterol, 4.16 (2.36-7.33) for low HDL-cholesterol, 1.49 (0.94-2.35) for high triglycerides, 1.46 (0.89-2.39) for high glucose, and 2.95 (1.90-4.59) for current smoking. A large reduction of the predictive value for myocardial infarction was shown after exclusion of high LDL-cholesterol (reduction of predictive value was -3.4%), further exclusion of low HDL-cholesterol (-7.1%), and further exclusion of current smoking (-16.4%).Conclusions: High LDL-cholesterol and low HDL-cholesterol as well as current smoking had high predictive values for myocardial infarction among Japanese middle-aged male workers.