Introduction. The aim of this review was to investigate the possible association between noise exposure and cortisol hormone in all noise-exposed job classifications. Materials and methods. In this systematic review, the Medline (PubMed), Scopus, Web of Science, and Embase databases were searched from 1 January 1991 to 28 September 2021. As a result, all English relevant papers among any group of workers, in any workplace, and at any noise level were included. Abstracts without full texts, editorials, letters, case reports, conference proceedings, reviews, in-vitro, and animal studies were excluded. Furthermore, studies were removed in the case that they were conducted on children or general population, did not measure the noise levels in work environments, and simulated the workplace noise or used a noise chamber. Results. The initial search retrieved 5784 articles. Finally, 13 articles were considered for qualitative synthesis. Among all the included studies, most of them (10 vs. three), conducted in various industries reported a statistically significant association between occupational noise exposure and increased levels of cortisol hormone. Conclusion. Our qualitative synthesis of available evidence proposed a potential relationship between occupational noise exposure and cortisol hormone. So, noise can be considered an occupational health concern.

Background: Road accidents, as the main causes of mortality and disability in the world, have been seriously endangering human health. Human factors are among the most significant causes of road accidents. This study aimed to investigate the association between high-risk behaviors among truck drivers with their fatigue and drowsiness in the occurrence of road accidents and near miss accidents. Materials and Methods: This descriptive study was conducted recruiting 200 truck drivers in Tehran using two-stage cluster sampling method, in 2019. A standard driver safety questionnaire was used to collect data, with its reliability measured by the testretest method. The Fisher's test, a chi-squared test, and the Pearson's correlation were used to analyze the data. Results: The mean age of the drivers and the mean hour of driving were 47.5 ± 9.05 years and 10.66 ± 2.52 hours, respectively. In addition, the number of accidents had a significant association with the drivers' age, drowsiness, talking on the cell phone, texting, eating snacks, and driving hours. However, it had no significant relationship with drinking tea and smoking. Furthermore, the rate of road accidents had a significant correlation with the drivers' driving time and rest hours. Conclusion: Behaviors and factors, such as talking on the cell phone, texting, eating snacks, long hours of driving per day, long hours of nonstop driving, low rest hours, and drowsiness were among the major causes of accidents among trucks drivers. In this regard, authorities are recommended to run educational courses to modify high-risk driving behaviors so as to reduce road accidents.

Background: activity in hot environments is among the most common physical dangers in work environments that not only creates diseases resultant from heat which influences on staff’s health but also increases job injuries and accidents. Job injuries, diseases, and reduction in workers' efficiency in exposure to heat stress have caused increasing anxiety. Most of the study results are demonstrative of diseases as a result of heat and less related to job injuries and accidents. Therefore, the present study aims at reviewing previous studies in the field of job injuries and accidents in exposure to the work environment's heat stress. Methods: this review study has systematically reviewed publications and articles from 2000 to 2019 in databases. Keywords including "heat stress”, “heat strain”, “heat exposure”, “heat wave", "heat injuries”, “job accidents”, “job exposure”, “hot environment” and “air change" have been used and finally, 30 articles included into the study. Results: study articles consist of 29 jobs and 1 military environment. Study occupations consist of one study about military forces, textile, aluminum smelting, cleaners of oil reservoirs, two studies about mineworkers and metal and iron industries, three studies about building workers, four studies about agricultural workers and 15 studies about different occupations. Also, 11 studies conducted in open environments, seven studies in closed environments and 12 others conducted both in open and closed environments. 17 analytical studies, three correlational, cross-sectional, cohort studies, one cohort, and descriptive study and two descriptive-analytical studies have been conducted. Most job injuries and accidents happened during summer and men especially the young have involved in such problems and job injuries and accidents have increased due to extreme temperature increase. Generally, job injuries and accidents include burn, slip, collision with things and collision with mobile things. Conclusion: there is a strong relationship between temperature in hot environments and risk increase in injuries and accidents of work environments which differ based on employees' features (such as age, gender, occupation, and industry). However, dominant mechanisms on the happening of such injuries have not been determined yet. It necessitates more expertise to determine especial injuries and accidents happening in hot environments. Policymakers and employers have to be more aware of job injuries and accidents in heat exposure and suitable educational resources have to be provided to prevent such injuries.