Journal of Health and Safety at Work

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Introduction: Stress is one of the major problems of living in industrial societies. Job and career issues are the most important causes of stress. Job stress is one of the important factors in causing psychological injury and illness in staff and decreasing productivity in organizations. Since human resources are among the most important assets of any organization, identification of the factors causing job stress is very crucial. Therefore current study aimed to investigate the causes of occupational stress in the staff of different units of the legal medicine centers in the Northwest Provinces.
 
Materials and Methods: A Descriptive-analytical study was conducted was designed and conducted on 166 employees of the various units of the legal medicines centers of Tabriz, Urmia, Ardebil and Zanjan cities by census statistical method during 2016-2017. Data were collected using questionnaires consist of demographic information and Cooper job stress questionnaire. The  collected  data  were  analyzed  by  means  of  SPSS  software  using  t-test  for  independent  groups,  ANOVA,  chi square, Pearson and  Spearman  correlation  coefficients, at the significant level of P<0.05.
 
Results: It was found that about 50% of the staff had moderate job stress and more than 12% had severe job stress. The comparison of mean job stress between healthy and ill individuals showed that the patients had a higher mean of job stress than healthy individuals, and this difference was statistically significant (P<0.001). The study of interference between work and life issue (family) also showed that the people whose work always interferes with their life issues had higher mean job stress than the other two groups and the difference was statistically significant (P<0.001). The result of this study also showed that there is a significant direct relationship between job stress and smoking (P<0.045), work interference and life issue (P<0.001), and a significant inverse relationship (P<0.044) with literacy.  Lower incomes, shifting the place of work, the heavy work, the ignorance of the managers to work problems, dealing directly with the people, the pressures due to the completion or working against deadlines, and the lack of hope for job promotion, respectively, are the factors causing stress in the organization.
 
Conclusion: Compared with employees of other organizations, the legal medicines staff seemed to have a much higher prevalence of stress. The organizational authorities could help staff to improve the quality of life and reduce occupational stress by creating the correct communication, desirable support and generating the appropriate environment for job activities.

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Introduction: Many studies have been carried out on the effects of heat stress on cognitive functions, but the results are contradictory. Therefore, this study was conducted to review the effect of heat stress on cognitive functions.
Material and method:  In this study, all English articles conducted on effect of heat stress on cognitive, perceptual, and psychomotor functions from 1970 to 2018 were reviewed. For this, articles with keywords such as heat strain, heat stress, cognitive function, memory, comprehension, psychomotor, reaction time, mental performance, mood, mental response, error, task performance, fatigue, alertness, hyperthermia, and heat exhaustion in the  Scopus, Web of Science, Science Direct, Pub Med, Springer, Wiley Online Library and ProQuest databases were searched. Out of 157 retrieved articles, 39 articles were finally reviewed according to the inclusion criteria.
Results: Out of 157 retrieved articles related to the topic, according to the inclusion criteria, 39 articles were finally considered for review. Among this articles, 9 (%23) articles were published before 2000 and 30 (%77) after 2000. Two articles were in athletes, four articles (%10.2) in workers, four articles (%10.2) in students, four articles (%10.2) in military soldiers and twenty-five articles (%64.2) were conducted in ordinary people.Based on the results, heat stress was identified as a detrimental factor for decreased cognitive functions such as reading comprehension, memory, focus, mathematical processing, tracking test, reaction time, perception  and decoding text and numeric messages, visual alertness, mental computing, text reading , hidden figures test and verbal fluency.
Conclusion: Based on the results of these studies, heat stress has been introduced as a detrimental factor for disrupting cognitive functions, but conclusion based on the results of studies is a systematic method is difficult because many confounding variables such as type of work, exposure time, skill and adaptation plays a big role.

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Introduction: Occupational stress is known today as one of the biggest challenges to higher education policy-makers. Students with high levels of stress find themselves lacking in self-confidence, vulnerable in controlling academic processes, and unable to compensate for clinical weaknesses. The main purpose of this study was to assess the levels of occupational stress among clinical dental students of Alborz University of Medical Sciences, Alborz, Iran.
Material and Methods: This study was a descriptive-analytic research with a cross-sectional design. The statistical population included all dental clinical students enrolled in the 7th, 9th, and 11th semesters in 2018 (n=84). According to the Krejcie and Morgan’s table, the sample size was 70. The data were also collected through the Osipow Occupational Stress Questionnaire, and then analyzed using the SPSS Statistics software (ver. 22). Besides, t-test was employed to investigate the relationship between variables and stress.
Results: The results revealed that the mean score of the students was 150.8. The mean total stress in the age group above 26 years was also 158 and that was 147 for those under the age of 26 (P-value=0.027). Besides, the mean score of overall occupational stress was equal in women and men. Comparisons also demonstrated that students in the 9th and 11th semesters (mean=161) were undergoing more stress than the ones enrolled in the 7th semester (mean=147) (P-value=0.014).
Conclusion: It was concluded that these clinical dental students were suffering from moderate-to-severe occupational stress. Likewise, older students had more stress than younger counterparts did. As well, male and female students’ levels of occupational stress were the same. Resolving this issue accordingly required special attention by higher education policy-makers to provide support and counseling in this respect.

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Introduction: Determining methods for assessing heat stress in different work environments is one of the major challenges for researchers in this field. The purpose of this study was to validate WBGT index and heat pressure assessment (HPA) by some physiological responses in Iranian South Oil Company.
Material and Methods: This descriptive-analytical study was carried out on 154 employees of Kharg, Asalouyeh and Mahshahr oil terminals recruited from three different working conditions including indoor, outdoor and rest environments in the summer. The amount of heat stress in the workplace was evaluated by WBGT index HPA method. To meet this purpose, the environmental parameters i.e., temperature, wet temperature, radiation temperature, relative humidity, water vapor pressure and air flow rate were determined. In addition to the direct reading method by the WBGT meter, ISO 7243 was used to calculate the WBGT index. In order to validate the heat stress indicators, physiological parameters of oral temperature, tympanic temperature and work metabolism were measured.
Results: The results of paired sample t-test showed a significant difference between WBGT index and HPA in indoor and outdoor environment (P<0.05). Moreover, there was a significant difference between the physiological indices of oral and tympanic temperatures and work metabolism in the indoor and outdoor environment (P<0.05). Furthermore, the correlation test was significant between WBGT index as an independent variable and HPA as a dependent variable (P<0.05)  and showed a high correlation (R2=0.914) between WBGT index with oral temperature and tympanic temperature . Also, the rate of work metabolism was significantly related with the aforementioned parameters (P<0.05) and was equal to R2=0.423, R2=0.335, R2=0.552, respectively. The correlations were also significant between HPA with Oral temperature, tympanic temperature and work metabolism (P<0.05)and were equal to R2=0.632, R2=0.605, R2=0.557, respectively. The results showed also that the correlation rate between the HPA with physiological parameters is stronger than that between physiological parameters with the WBGT index.
Conclusion: This study showed that WBGT and HPA methods are useful for assessing the heat stress of Iranian South Oil Company. Also, the HPA method is more reliable for assessing heat stress in these regions.

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Introduction: Damage to occupational health is one of the major challenges in the industry. Various studies have shown that productivity in industries has a significant relationship with occupational health. In addition, employee’s health in the workplace can be affected by a variety of variables i.e., job stress, job satisfaction, and work in unconventional shifts. Therefore, the purpose of this study was to evaluate the causal relationships of shift work, job stress, job satisfaction with the occupational health level in a petrochemical industry.
Material and Methods: This cross-sectional study was implemented in 2017. The study sample consisted of 20 HSE experts selected using purposeful judgment sampling. A 4×4 matrix questionnaire consisting of four main parameters i.e., shift work, job stress and job satisfaction with occupational health level, was used for data acquisition. Data analysis was done using MATLAB software and Fuzzy DEMATEL method. Also, for each variable, two key values of D+R and D-R were calculated. These values show the degree of interaction and the type of interaction of the variable with other variables, respectively.
Results: Sixty percent of the experts participating in this study were male and 40.0% were female. Only 10.0% of the participants had a PhD degree. In addition, the mean age and the mean work experience of the subjects were 39.64±9.34 and 10.22±7.10 years, respectively. The parameters of shift work and job satisfaction were identified as an effective factor due to the positive values of D-R while occupational health variable with negative value of D-R, was considered as an affected factor. In addition, these results showed that the effect of these parameters on health is different with both direct and indirect mechanisms.
Conclusion: Using the Fuzzy DEMATEL method, our findings indicated that occupational health in the large industries can be influenced by different parameters with different sizes. Considering the interactions among these parameters in health analysis and the affecting factors, therefore, is very important. So, the health level in challenging industrial environment such as petrochemical industries can be affected by shift work as a root cause. This root cause, along with job satisfaction, has a significant effect on increasing stress levels and reducing health levels. Accordingly, any action to increase the health level should focus on improving shift patterns and increasing the level of job satisfaction of employees as a pivotal root and affecting causes on health level.

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Introduction: These days, there is a consensus that emotional intelligence plays an important role in the success of individuals in different areas of life. Persons with higher emotional intelligence had lower stress in dealing with demands and pressures in the workplace. The purpose of this study was to use artificial neural network to predict job stress and to compare the performance of this model with the multivariate regression model.
Material and Methods: In order to do that, 892 participants were selected randomly in different job categories. Then, 15 dimensions of Bar-On questionnaire, 10 job categories, age and education were considered as input variables and 7 dimensions of health and safety executive HSE were determined as output variables in models.
Results: The results revealed that an artificial neural network with hyperbolic tangent and sigmoid transfer functions respectively in hidden and output layers with 375 hidden neurons had significantly better performance than multivariate regression. So that, correlation of predicted values and job stress were only between 0.192-0.364 in regression model, but neural network had at least correlation 0.527 in all dimensions of job stress.
Conclusion: In predicting job stress using emotional intelligence, artificial neural network method was much better than multivariate regression model.

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Introduction: Heat stress is a critical problem in hot industries, especially in incredibly hot climates. It can greatly impair the work process and put the health of workers at risk. This study aims to investigate the applicability of the WBGT index in determining the allowable working time in very hot weather conditions in one of the steel industries in Ahvaz.
Material and Methods: This study was conducted in different sectors of a steel industry in Ahwaz. The physiological parameters of sixty workers working in different parts of the industry were evaluated. Environmental variables and the Wet-Bulb globe temperature (WBGT) Index were also simultaneously measured during work shifts. The acceptable work time was calculated based on the reserve heart rate (RHR) and the WBGT index.
Results: The heat stress index among all occupational groups, based on the WBGT index, was incredibly high and surpassed the recommended level (P<0.05). The statistical test results also indicated a significant difference between the two indices in predicting the adequate work time at different work stations (P <0.05).
Conclusion: The current study results revealed that using the WBGT index for assessing and managing the risk of heat exposure in a hot climate may not have sufficient reliability and performance. Consequently, it is recommended to use optimal indices based on environmental and physiological assessments in a hot climate in order to monitor and control the heat stress associated with heat exposure. 

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Introduction: Prevention of heat-related diseases requires the participation of the workers. For this reason, the aim of this study was the development and validation of the tools for evaluating awareness and practice related to heat stress among the workers of warm workplaces.
Material and Methods: The various items and factors related to the awareness and practice of the workers were identified by the literature review. Then, several questions for evaluating these items were designed. In the next step, the reliability and validity of the questionnaires were appraised using calculating the content validity ratio (CVR) and content validity index (CVI), and Cronbach’s alpha coefficient, respectively. After that, these questionnaires were completed by 2338 employees of six industries in various regions of Iran. Finally, collected data were analyzed using SPSS software.
Results: In total, 77 questions, including 53 questions on awareness and 24 questions on practice in six groups of water and beverages, food, snacks and additives, heat exchange, thermal strain risk factors, clothing and heat protection equipment, and heat-related disorders and body reactions, were designed. The values of content validity index (CVI) of remained questions in the questionnaires of awareness and practice were equal to 0.954 and 0.824, respectively. The values of Cronbach’s alpha coefficients of these questionnaires were calculated by 0.755 and 0.716, respectively. The values of the chi-square divided by degrees of freedom (CMIN/DF) and root mean square error of approximation (RMSEA) in the construction of the awareness questionnaire were computed as 4.58 and 0.079, respectively. These values in the construction of the practice questionnaire were calculated by 2.33 and 0.084, respectively.
Conclusion: The results showed that the designed questionnaires had appropriate reliability and validity and could be used to evaluate the awareness and practice in warm workplaces.

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Introduction: Studies show that in many cases, environmental hazardous agents such as heat, noise, as well as chemical pollutants cause adverse health effects through the mechanism of oxidative stress. This study has examined the effect of exposure to noise and whole-body vibration (WBV) on some parameters of oxidative stress (enzyme superoxide dismutase (SOD), total antioxidant capacity (TAC), and malondialdehyde (MDA)) of workers in a foundry industry.
Material and Methods: The workers were selected based on the calculations related to the sample size and taking into account the inclusion criteria as well as completing the informed consent form. The level of exposure to noise and WBV was measured according to ISO 9612 and ISO 2631, respectively. For each worker, the time-weighted average was calculated. The level of exposure of workers to the studied stressors was divided into three categories: low, medium, and high. The blood samples were taken from all participants between 7-9 am. Then, via ELISA method according to the protocol of the kit manufacturer, the samples were prepared and analyzed. Univariate analysis of variance was performed to determine the “effect size” of each physical stressors on the studied parameters.
Results: The mean levels of MDA, SOD, and TAC among participants were 22.48 (11.19) nmol / ml, 61.28 (10.97) U / ml, and 1.64 (0.90) mM, respectively. Among the exposure variables, noise had the largest effect on MDA level (B = 0.090), which was not statistically significant (P = 0.865). WBV had the largest effect on SOD level (B = -1.469) which was statistically significant (P = 0.016). None of the studied variables had a significant effect on the TAC level; however, among the exposure variables, the greatest effect was related to WBV (B = -0.077; P = 0.133).
Conclusion: The effect of noise on oxidative stress parameters was not statistically significant. The effect of whole-body vibration on oxidative stress parameters except SOD was not statistically significant. Noise and WBV had increasing effect on MDA and decreasing one on SOD and TAC levels.

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Introduction: Health workers, especially nurses, are facing a high risk of contracting the COVID-19 and consequent mental disorders such as stress, anxiety and depression. We aimed to study the relationship between anxiety, stress and the protective behavior of nurses during the Covid-19 pandemic.
Material and Methods: This cross-sectional study was conducted on nurses working in COVID -19 referral hospitals in Qazvin, Iran, in 2020. Out of 645 nurses working in two hospitals, 260 of them were selected randomly. Three questionnaires including demographic and contextual information, COVID-19 anxiety, stress and precautionary behaviors against COVID-19 were used. Descriptive statistical methods, Pearson correlation, t-test and one-way analysis of variance and binary logistic regression analysis were applied at 95% confidence interval.
Results: The prevalence of anxiety symptoms in nurses was 32.08%, the mean score of protective behavior was 18.45+5.66 and the maximum score was 22.06+4.7. The negative relationship between anxiety and nurses precautionary behavior) β=-0.36, P<0.05) and the significant effect of COVID-19 stress on nurses’ behavior) β=-0.22, P<0.05) were confirmed. Furthermore, adding stress as an interfering factor, affirmed the mediating role of stress in the relationship between anxiety and nurses’ precautionary behavior (β=-0.18, P<0.05). Nurses under 35 years of age were more likely (OR=1.62, P=0.004) to follow the protective rules; those with 6 to 10 years of hospital experience were respectively 32 times and 37 times more probable to use personnel protective equipment (PPE) (OR=1.32, P=0.002) .
Conclusion: The probability of effective use of PPE and observance of protective guidelines among nurses with severe and very severe anxiety levels was less than their counterparts. While in those with controlled level of stress level such obedience was much more probable. Therefore, all health service providers, need to develop supportive programs to emphasize on the promotion of employees’ mental health.

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Introduction: Climate change and hot processes in the workplaces has led to an increase in the effects of heat stress on employed people, which has become a major concern, especially in tropical and subtropical countries. Early detection of biomarkers in induction of heat stress-related DNA damage can be used in the identification and evaluation of health and safety, including occupational health professionals, as well as to prevent serious diseases caused by heat stress in various occupations with the nature of hot processes or to help different warm seasons of the year. Therefore, this review study was conducted to identify diagnostic biomarkers heat stress induced- DNA damage in occupational exposure.
Material and Methods: Databases such as PubMed, Scopus, Google Scholar, and Web of Science were systematically searched to meet the study’s goals. Moreover, references to relevant publications were examined. Finally, suitable articles were selected and analyzed using the inclusion (studies on different occupations, different biomarkers in hot work environments, all articles published without time limit until the end of April 2022 , and English and Persian language)  and exclusion criteria.
Results: The results of search in databases showed that 9234 articles were found in the initial search. After removing duplicate and unrelated articles, 2209 eligible articles were selected. Based on abstract full-text screening, 7166 studies were excluded, and based on abstract full-text screening, 21 studies were not accessible. Finally, seven articles were selected to be reviewed. The evidence showed that diagnostic biomarkers included the measurement of 8-hydroxy-2-deoxyguanosine (8-OHdG), micronuclei semen quality, heat shock proteins (HSP70), and leukocytes were extracted to heat stress induced- DNA damage in occupational exposure.
Conclusion: Based on a review of studies,  biomarkers identified are suitable for heat stress induced- DNA damage as a result of occupational exposure to extremely high heat climate conditions. Understanding and identifying appropriate biomarkers in inducing DNA damage can help health and safety professionals determine the amount and magnitude of heat stress responses in occupational exposure to different temperatures and take appropriate measures and interventions to control and reduce the hazard effects of thermal stress. This study can also be considered as a preliminary study for research in the future.

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Introduction: Many industries have multiple factors harmful to health, leading to simultaneous exposure of these factors to each other. Noise is one of the most common physical parameters in the work environment. On the other hand, heat is also increasing due to various energy processes in industries. Therefore, this study was conducted with the aim of determining changes in physiological parameters and visual-auditory attention in acute exposure to heat and noise.
Material and Methods: In this experimental study, 72 individuals (36 men and 36 women) aged between 23 and 33 years participated according to the inclusion criteria. In total, 12 different test modes were performed (3 temperature levels and 4 noise pressure levels). The test was conducted for each person in 4 steps during a specific day. The duration of exposure to each condition was half an hour, and a half-hour rest was given between each test condition. Saliva samples of each subject were collected before and immediately after exposure to noise and heat. Also, The Integrated Visual and Auditory (IVA) was recorded by the participants simultaneously.
Results: The results of combined exposure to noise and heat on visual and auditory attention showed that only two modes of combined exposure, SPL95+WBGT34 and SPL95+WBGT29, caused a significant increase (P < 0.05) in mental workload and a significant decrease (P < 0.05) in visual and auditory attention. In addition, the results showed that independent exposure to noise at the levels of 85 and 95 dB and exposure to heat at higher temperature levels of 34 and 29 degrees Celsius cause a significant increase (P < 0.05) in salivary cortisol after exposure. The results of the effect of combined exposure to noise and heat on salivary cortisol showed that three experimental modes of combined exposure (SPL85+WBGT34, SPL95+WBGT29, and SPL95+WBGT34) caused a noticeable and significant (P<0.001) increase in salivary cortisol.
Conclusion: Indeed, salivary cortisol can be recommended as a physiological index to evaluate noise and heat exposure. It’s also noteworthy that salivary cortisol is more affected by noise and heat exposure than cognitive performance.

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Introduction: Emergency technicians face workplace violence and increasing occupational stress. The purpose of this study was to investigate the impact of a virtual self-management training in communication skills on occupational stress and the degree of aggression among emergency technicians.
Material and Methods: This study involved 60 emergency technicians randomly assigned to either the intervention or control group. They completed surveys on workplace violence and occupational stress. The intervention group received six weeks of a virtual self-management training in communication skills. Data was collected after two months and analyzed using SPSS software.
Results: The findings showed that there was no statistically significant difference between the control group (110.08±11.92) and the two intervention groups (114.39±11.25) in terms of the average occupational stress before the intervention; The average job stress score between the intervention (94.0±12,70) and control (98.81± 20,81) groups significantly differed following the intervention (p=0.034); After the intervention, the intervention group had lower verbal and physical abuse frequencies compared to the control group.
Conclusion: The virtual self-management communication training demonstrated the potential to reduce occupational stress but did not significantly decrease the violence towards the emergency technicians. A comprehensive training program addressing violence factors and communication techniques, implemented over a longer period, is recommended.

 

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Introduction: Workers who work in warm situations need clothes with better thermal regulation. Nowadays, improving the thermal regulation properties of cotton fabric by treating it with phase change materials (PCMs) has been considered. The type of fabric plays an important role in providing thermal comfort. Cotton fabric is the most popular raw material in the textile industry due to its distinctive features. Therefore, this systematic review aims to investigate the effects of PCM nanoencapsulation in commonly used cotton fabrics, including morphology, thermal properties, thermal stability, tensile strength, abrasion resistance, leakage, water absorption, washing ability, and breathability of the fabric, related challenges, and future research trends.
Material and Methods: This research was conducted with the papers obtained from the systematic search in Science Direct, Web of Sciences, Scopus, and PubMed databases. Keywords “nanoencapsulated phase change materials”, “nanoenhanced phase change materials”, “cotton”, “cotton fabric”, and “cotton textiles” were used.
Results: Of the 1251 studies identified through search databases, 13 were selected according to the entry criteria. The results revealed that in all the studies, PCM nanocapsules were successfully synthesized and inserted into the cotton fabric, improving the fabric’s thermal properties. Most studies used in situ polymerization and mini-emulsion polymerization for nanoencapsulation. The pad-dry-cure method was also widely used for applying nanocapsules to cotton fabric.
Conclusion: This systematic review showed that synthesized nanocapsules of phase change materials and applied them to cotton fabric can improve the thermoregulating properties of the fabric. It is suggested to expand the research to design thermoregulating clothes made from treated fabrics and investigate their cooling performance.

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Introduction: Mental health in the workplace is a critical factor influencing both employee well-being and organizational productivity. However, issues such as stress, anxiety, depression, and burnout can significantly impair job performance and overall quality of life. While numerous tools have been developed to assess mental health, many are not specifically designed or updated for work environments. As the complexity of the workplace continues to increase, accurate identification and evaluation of these conditions become increasingly essential. This study aims to review available tools and identify the most proper methods for screening and assessing mental health issues in the workplace.
Material and method:  A scoping review approach was used to identify mental health assessment tools applicable to workplace settings. The PubMed, PsycINFO, Web of Science, and Scopus databases were searched using keywords related to mental health at work. Studies published after 2020 were included, focusing on tools developed and validated in work environments. Two authors independently extracted and reviewed data from selected studies. Tools were categorized based on their aims and specific characteristics.
Results: After screening, 12 studies were selected from a primary set of 746 papers.. The extracted tools were designed to assess stress, anxiety, depression, and burnout. While most tools were developed for general settings or the public, some were appropriated to specific occupational groups, such as military personnel and healthcare workers. Burnout assessment tools were the most frequently referenced category.
Conclusion: Newer tools, such as the Work Stress Screener, Occupational Depression Inventory, and Burnout Assessment Tool, offer potential advantages over older instruments. Shorter, specialized tools are recommended to assess job anxiety effectively. Organizations should prioritize selecting tools that align with their employees' specific working conditions to promote mental health and productivity.

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Introduction: Heat stress is a common environmental risk factor for many occupations, which can lead to increased fatigue during cognitive tasks. Fatigue is a multifactorial phenomenon that is affected by various environmental, physiological, and psychological factors, and can affect biomechanical, physiological, and psychological components. This study focuses on the impact of environmental, individual, and physiological factors, and burnout on general fatigue.
Material and Methods: This descriptive-analytical study was conducted among 189 employees of the Iran Oil Company at both indoor and outdoor workstations. Heat stress was measured using the (WBGT) index, and thermal strain risk was evaluated. Variables such as skin temperature, ear temperature, blood pressure, and heart rate were also monitored. To assess general fatigue and occupational burnout, (MFI) and the Maslach Burnout Inventory were completed by the employees.
Results: The results revealed that 79.9% of the employees were exposed to heat stress, with repair workers experiencing the highest levels of emotional exhaustion (23/38), depersonalization (15/34), general fatigue (10/00), and physical fatigue (9/05).  Statistically significant relationships were found between heat stress and fatigue and decreased motivation, between all components of burnout and general fatigue, and between core temperature, blood pressure, and general fatigue (p<0.05). Notably, demographic factors such as marital status, smoking status, and education level did not significantly influence fatigue scores.
Conclusion: Fatigue is strongly associated with heat stress, physiological variables such as body temperature and blood pressure, burnout, personal habits such as sleep duration and exercise, and the type of job. These findings suggest that in hot work environments, monitoring physiological variables and environmental factors can help identify and address fatigue issues.

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Introduction: Wearable thermal management systems and phase change materials (PCMs) have emerged as effective solutions for regulating body temperature and storing thermal energy. This study focuses on synthesizing and thermal optimizing a sodium sulfate decahydrate-based nanocomposite incorporating various nanoparticles to improve its performance for personal thermal regulation applications.
Material and Methods: The composite was prepared using sodium sulfate decahydrate as the base PCM. Potassium chloride (KCl) was added to adjust the melting point, borax (STD) served as a nucleating agent, and sodium polyacrylate (SPA) was included as a thickening agent to suppress phase separation. To evaluate the effect of nanoparticle additives, 0.05 wt.% of aluminum oxide (Al₂O₃), iron oxide (Fe₂O₃), graphene oxide (GO), and titanium dioxide (TiO₂) were separately incorporated into the base formulation. A field emission scanning electron microscope (FESEM) was used to analyze the surface morphology of the resulting nanocomposites. Differential scanning calorimetry (DSC) assessed thermal properties, including phase transition temperatures (melting and freezing points) and latent heat.
Results: Differential scanning calorimetry (DSC) analysis indicated that sample S-5-5 comprising sodium sulfate decahydrate with 3 wt.% KCl, 5 wt.% STD and SPA exhibited a melting temperature of 29.5 °C and a latent heat of 120 J/g. This composition remained stable without phase separation. The incorporation of nanoparticles raised the melting point of the base PCM by 0.6 to 1.72 °C. Aluminum oxide (Al₂O₃) and iron oxide (Fe₂O₃) reduced the latent heat of fusion, whereas GO and TiO₂ increased it.
Conclusion: These findings confirm that the thermal properties of sodium sulfate decahydrate-based PCMs can be tailored by including specific additives and nanoparticles. Hydrated salt nanocomposites demonstrate strong potential as PCMs for wearable body temperature regulation.

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Introduction: The rising daily consumption of gasoline has increased human exposure to its vapors. Direct contact with these vapors, due to their toxic properties, can adversely affect various organs, including the heart, lungs, skin, liver, and kidneys. Cinnamon, a widely utilized medicinal plant, is rich in antioxidants and exhibits protective effects on liver and kidney health, alongside therapeutic potential for various diseases. Therefore, this animal study aimed to investigate the protective effects of cinnamon extract against oxidative stress induced by gasoline inhalation in rat kidneys.
Material and Methods: Thirty adult male Wistar rats weighing 160–180 grams were randomly divided into five groups (n=6 per group): (1) Control, (2) Cinnamon extract only, (3) Gasoline exposure only, (4) Gasoline exposure plus 100 mg/kg of cinnamon extract, and (5) Gasoline exposure plus 200 mg/kg of cinnamon extract. After four weeks of exposure, the rats were weighed and euthanized. Serum samples were collected for biochemical, serological, and enzymatic analysis, and kidney tissues were examined for histopathological changes.
Results: Gasoline exposure significantly increased kidney function markers (BUN and cystatin C) and oxidative stress markers (MDA) while reducing endogenous antioxidant activities (GSH and GPx). Histopathological analysis revealed significant kidney damage, including hemorrhage, necrosis, and tubular degeneration in the gasoline-exposed group. Cinnamon extract notably alleviated gasoline-induced kidney toxicity by reducing kidney function markers and MDA levels while enhancing endogenous antioxidant activity. Histopathological findings further confirmed the protective effects of cinnamon extract, showing reduced tissue damage in treated groups.
Conclusion: Cinnamon extract significantly reduces kidney toxicity caused by gasoline, suggesting it may protect against gasoline exposure. Its antioxidant and anti-inflammatory properties likely support this protective effect.

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Introduction: Work-family conflict can lead to negative outcomes such as psychological distress in all employees, especially female nurses, as they face unique occupational challenges. However, the specific aspect of work-family conflict that contributes most significantly to psychological distress, as well as the underlying mechanisms involved, has not been thoroughly examined. The present study aimed to investigate the relationship between work-family conflict dimensions and psychological distress.
Material and Methods: This descriptive-analytical study was conducted in 2022 on 277 female nurses employed at public hospitals in Bushehr Province. The data collection tool consisted of work–family conflict and psychological distress questionnaires. The data were analyzed using SPSS v. 19 and PLS Graph v. 3, with path analysis.
Results: The direct effects of two dimensions of work-family conflict, namely “the interference of work with personal and family life” and “the interference of family life with work,” on psychological distress were found to be statistically significant (p < 0.05). In addition, the mediating effect of the “work interference with personal and family life” on the relationship between “insufficient facilities and support” and psychological distress was statistically significant (p < 0.05). Meanwhile, the mediating effect of the “family dissatisfaction” in the relationship between “the interference of work with personal and family life” and psychological distress was not statistically significant (p > 0.05).
Conclusion: The interference of work with personal and family life, and the interference of family life with work, were identified as significant factors that directly affect psychological distress. In addition, “insufficient support and facilities” can increase “the interference of work with personal and family life”, thereby leading to greater psychological distress among female nurses. Planning to enhance support measures in both the workplace and personal life can help reduce the negative consequences of work-family conflict, such as psychological distress in female nurses. 

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Introduction: Climate change is a major global challenge, strongly influencing the Wet Bulb Globe Temperature (WBGT) index and heat stress among steel industry workers. This study evaluates the impact of geographical location and climate change on occupational heat stress exposure in Iran’s steel sector.
Material and Methods: This qualitative-analytical study used data from the SABA system and the Iranian Occupational Heat Stress Atlas. Information on steel industries, their distribution, and production capacities across eight climate zones was extracted. WBGT measurements were collected in collaboration with industrial units in different zones. Data analysis was performed using ArcGIS and SPSS. The effects of climate change on heat stress were assessed for three future horizons: 2040, 2060, and 2080.
Results: The findings revealed that climate zones G1 (eastern, southeastern, and desert regions) and G4 (Persian Gulf coastal provinces including Hormozgan, Bushehr, Fars, and Khuzestan), which host the highest steel production capacities, are exposed to the highest levels of heat stress (WBGT index) and water resource scarcity. WBGT values in zones G4 and G6 (Gilan province) exceeded permissible limits, whereas zones G2 (including North Khorasan, Razavi Khorasan, Tehran, Alborz, Qazvin, Hamedan, Markazi, and Chaharmahal-Bakhtiari), G5 (Kurdistan, Kermanshah, Lorestan), and G7 (Ilam, Kohgiluyeh and Boyer-Ahmad) showed the lowest WBGT levels. Considering projected temperature increases in the three future horizons and the acceptable correlation coefficient (0.40) between annual daytime temperature and WBGT index per climate zone, predicted temperature changes may lead to increased WBGT levels, particularly in zones G3, G6, and G8.
Conclusion: Given climate projections and the spatial distribution of steel industries, it is essential to develop climate-responsive policies, implement sustainable water resource management, and reconsider the siting of steel production units. These measures can enhance the resilience of Iran’s steel industry against future climate change and mitigate occupational health and environmental risks.