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The association between heat or heat waves and mortality should often be reported in a way that makes it sensible by health policymakers. In this study we aimed to assess the effect of heat and heat waves on mortality using attributable risks during 2005-2017. Nine heat waves were defined using a combination of severity and duration of mean daily temperature. Heat wave effects were assessed using added and main effects. Added effects were assessed as a binary variable and main effects were assessed by comparing the median temperature (in heat wave days) to Minimum Mortality Temperature (MMT). The effects of heat, mild heat and extreme heat on mortality were also assessed. Distributed Lag Non-linear Models were used to assess the relations in a bi-dimensional perspective in which the quadratic b-spline was chosen as the basis function for the dimension of the exposure and the natural cubic b-spline was chosen for lag dimension. The backward perspective was used to estimate the attributable risks. The total mortality attributed to non-optimal temperatures for all days was 1.91% (CI 95%: -6.36, 8.47). The attributable risks (AR) were 2.23%, 2.02% and 0.25% for heat, mild heat and extreme heat days, respectively. AR was more for females and the above 65 years old groups than other groups in heat, mild heat and extreme heat days. While the stronger heat waves defined based on temperature above the 95 and 98th percentile had a significant attributable risk for total mortality in the added effects; the weaker heat waves (defined based on temperature above of the 90th percentile (HW1, HW2, HW3) had higher attributable risks, significant for HW1 and HW2, in the main effects. Apparently weaker heat waves show more immediate effects, while stronger heat waves increase mortality over several days.

Noise levels experienced by industrial workers may cause both auditory and non-auditory harmful effects. We have studied the effects of chronic industrial noise exposure on DNA damage, blood pressure, and serum biochemistry in factory workers. Male workers (109 individuals) in three parts of a food factory in Shahroud, Iran were enrolled as the exposed group and male office workers (123 individuals) were the unexposed control group. Noise exposure was measured (dosimetry) and the comet assay was used to evaluate DNA damage in peripheral blood mononuclear cells. Glutathione peroxidase (GPx) and ceruloplasmin (Cp) levels were measured in serum samples. GPx levels, systolic and diastolic blood pressure, and DNA damage were significantly higher in the exposed group than in the control group. However, ceruloplasmin levels were not significantly different. Based on multivariate linear regression analysis, noise exposure was the most important predictor of GPx levels, systolic and diastolic blood pressure, and DNA damage.

School bullying is a major global public health problem that may associate with school factors. Few studies have been conducted in Middle East countries and in Iran about the association between the environmental characteristics of school and bullying victimization and perpetration. The Persian-OBQ and school environment scale of MDS3 Climate Survey was completed by 1540 Iranian students from 42 schools. This study examined the association of student perceptions about school environment both at the collective and individual level (including 4 dimensions: rules, physical comfort, support, and disorder) and the experience of involvement in bullying victimization, perpetration, and both of verbal, relational, physical, and cyber forms, using a contextual effect model in a two-level multinomial modeling. Results showed that higher individual-perception of physical comfort and support were related to lower levels of involvement in verbal, relational or cyber forms; and higher individual-perception of disorder was related to a greater level of involvement in verbal and relational forms. Whereas a higher collective-perception of rules, physical comfort, support, and disorder were related to a greater level of involvement in all forms, except the relational only-victim form. The implications of these results for building a supportive school environment are discussed.

Air pollution is likely to have adverse effects on human health. This study was conducted to determine the effect of air pollution on respiratory disease hospital admission in Ahvaz, one of the most polluted cities in the Middle East. Daily information about respiratory disease admissions and air pollutants during 2008–2018 were inquired. Adjusted Quasi-Poisson regression combined with linear distributed lag models were used. There was a significant relation between increased O3 and respiratory hospital admissions for 65–74 year olds, ≥75 year olds, and pyothorax-abscesses of the lung and mediastinum; between increased NO and respiratory hospital admissions for ≥75 year olds, chronic lower respiratory diseases, diseases of upper respiratory tract and respiratory diseases principally affecting the interstitium; between increased NO2 and respiratory hospital admissions for ≥75 year olds; between increased CO and respiratory hospital admissions and between increased SO2 and respiratory hospital admissions for ≥75 year olds. The risk of respiratory hospital admissions increased in both males and females for increase in PM2.5. Ambient O3, NO, NO2 CO and SO2 can increase admission for respiratory diseases on the same day and at short lags in Ahvaz. This evidence emphasizes the need to implement policies for reducing air pollution.

Recently there has been a lot of interest in global warming and temperature variation's effect on health. This study evaluates the impact of Diurnal Temperature Range (DTR) on mortality in Tabriz, northwest of Iran. Distributed Lag Non-linear Models combined with a quasi-Poisson regression were used to assess the impact of DTR on cause, age and gender specific mortality, controlled for potential confounders such as long-term trend of daily mortality, day of week effect, holidays, mean temperature, humidity, wind speed and air pollutants. As the effect of DTR may vary between the hot season (from May to October) and cold season (from November to April of the next year), we conducted analyses separately for these two seasons. In high DTR values (all percentiles), the Cumulative Relative Risk (CRR) of Non-Accidental Death, Respiratory Death and Cardiovascular Death increased in the cold season. In full year and high DTR value (percentile 90), the CRR of respiratory deaths increased as well (CRR, Lag 0-6:1.32(1.006, 1.75). Although there was no clear significant effect in low DTR values, high values of DTR increase the risk of mortality in the cold season, in Tabriz, Iran.

Cardiovascular disease is one of the main causes of death in Iran. The aim of this study was to determine the relation between air pollution and cardiovascular hospital admissions in Ahwaz, Iran. Daily information about cardiovascular hospital admissions (based on the ICD-10) and data on air pollutants during 2008-2018 were inquired. A quasi-Poisson regression combined with linear distributed lag models; adjusted for trend, seasonality, temperature, relative humidity, weekdays and holidays was used to assess the relation between hospital admission for cardiovascular diseases and the average daily air pollution. The results of this study showed a significant increase in cardiovascular hospital admissions in the total population and women's population in relation to O3. There was a significant increase in hospital admissions for cardiovascular diseases in the whole population as well as gender and age groups associated with NO2 and NO. A significant increase was found in hospital admissions for cardiovascular diseases in relation to CO in the 65-74-year-old population. Finally, the results of this study showed that there was a significant increase in hospital admissions for cardiovascular disease associated with SO2. The main results of the present study confirm the deleterious short term impact of air pollution on cardiovascular morbidity in Ahvaz city. This evidence empasizes the need to implement policies for reducing air pollution.

Introduction Heat stress disrupts blood hormones and reduces workers' cognitive performance. To further shed light on the dysfunction of heat stress, the present study aimed to evaluate its effect on cognitive performance of petrochemical workers. Materials and methods This descriptive-analytical cross-sectional study was conducted in 2020 in one of the Iranian petrochemical companies. Participants were divided into 2 case groups and 1 control group. They worked 12 h and their shift entialed one week working day and one week working night. According to the ISO 7243 standard, the heat stress index of employees was measured at the beginning, in the middle and at the end of the shift separately. Continuous Performance Test (CPT) and N-back cognitive performance tests were performed at the beginning, in the middle and at the end of the shift to determine the level of cognitive performance. The data were analyzed using SPSS software version 20 and the significance level was set at 0.05. Results Comparison of the results in the continuous performance test showed significant differences between the three groups with regard to the omission error and response time at the end of the shift. Moreover, according to the working memory test, participants reaction time during the shift significantly increased. Besides, average correct responses significantly reduced during the shift. Finally, the heat stress throughout the shift had a significant effect on the commission error and the response time of individuals. Conclusion Heat stress affects people's cognitive performance in such a way that it can decrease their cognitive performance by increasing the commission error and response time and reducing the average correct response of site operators, generally reducing the cognitive performance of people at the end of the shift., Heat; Cognitive performance; Petrochemical company; Continuous performance; Working memory.

Introduction In the process of treatment and prevention of relapsing to drug use, it is important to pay attention to mental health and supportive training interventions based on empowerment models. The present study was conducted to investigate the impact of training intervention based on the family - centered empowerment model upon the severity of damages caused by addiction among methamphetamine (MA) users. Material and methods This study was a randomized trial. Subjects were divided into the intervention (95 individuals) and control (95 individuals) groups, randomly. The data collection tools included a demographics checklist and the Addiction Severity Index (ASI) standard questionnaire which were completed before, and three and six months after the educational intervention. The educational intervention was conducted in nine 90-minute sessions using the 5As method, group discussion and distribution of educational pamphlets. Statistical tests like the independent and paired t-test were used to analyze data. Results The research findings indicated that the average scores of ASI subscales including family status, mental status and use of drugs were significantly different between before and three months after the training intervention in the intervention group (P Conclusions It was feasible to implement the family-centered empowerment model among MA users and it improved the severity of damages caused by drug abuse.

There are few epidemiological studies about climate change and the effect of temperature variation on health using human thermal indices such as the Physiological Equivalent Temperature (PET) Index in Iran. This study was conducted in Tabriz, the northwest of Iran and Distributed Lag Non-linear Models (DLNM) combined with quasi-Poisson regression models were used to assess the impacts of PET on mortality by using the DLNM Package in R Software. The effect of air pollutants, time trend, day of the week and holidays were controlled as confounders. There was a significant relation between high (30°C, 27°C) and low (-0.8°C, -9.2°C and -14.2°C) PET and total (non-accidental) mortality; and a significant increase in respiratory and cardiovascular deaths in high PET values. Heat stress increased Cumulative Relative Risk (CRR) for total (non-accidental), respiratory and cardiovascular mortality significantly (CRR Non Accidental Death, PET=30°C, lag 0-30=1.67, 95%CI: 1.31-2.13; CRR Respiratory Death, PET=30°C, lag 0-13=1.88, 95%CI: 1.30-2.72; CRR Cardiovascular Death, PET=30°C, lag0-30=1.67 95%CI: 1.16-2.40). Heat stress increases the risk of total (non-accidental), respiratory mortality, but cold stress decreases the risk of total (non-accidental) mortality in Tabriz which is one of the cold cities of Iran.

Diurnal Temperature Range (DTR) is a meteorological index which represents temperature variation within a day. This study assesses the impact of high and low values of DTR on mortality. Distributed Lag Non-linear Models combined with a quasi-Poisson regression model was used to assess the impact of DTR on cause, age and gender specific mortality, controlled for potential confounders such as long-term trend of daily mortality, day of week effect, holidays, mean temperature, humidity, wind speed and air pollutants. As the effect of DTR may vary between the hot season (from May to October) and cold season (from November to April of the next year), we conducted analyses separately for these two seasons. In high DTR values (all percentiles), the Cumulative Relative Risk (CRR) of Non-Accidental Death, Respiratory Death and Cardiovascular Death increased in the full year and hot season, and especially in lag (0−6) of the hot season. In the cold season and high DTR values (all percentiles), the CRR of Non-Accidental Death and Cardiovascular Death decreased, but the CRR of Respiratory Death increased. Although there was no clear significant effect in low DTR values. High values of DTR increase the risk of mortality, especially in the heat season, in Urmia, Iran.

Background Estimating the effects of climate change on human health can help health policy makers plan for the future. In Iran, there are few studies, about investigating the effects of climate change on mortality. This study aimed to project the effect of low (cold) and high (heat) temperature on mortality in a dry region of Iran, Kerman. Methods Mortality attributed to temperature was projected by estimating the temperature-mortality relation for the observed data, projection of future temperatures by the statistical downscaling model (SDSM), and quantifying the attributable fraction by applying the observed temperature-mortality relation on the projected temperature. Climate change projection was done by three climate scenarios base on Representative Concentration Pathways (RCP2.6, RCP4.5 and RCP8.5). Adaptation was considered by using different minimum mortality temperatures (MMT) and risk reduction approaches. The current decade (2010–19) was considered as the reference period. Results All three climate change scenarios, showed that the mean of temperature will rise about 1 °C, by 2050 in Kerman. The number of deaths attributed to heat were obviously higher than cold in all periods. Assuming no adaptation, over 3700 deaths attributed to temperature will happen in each decade (2020s, 2030s and 2040s) in the future, in which over 3000 deaths will be due to heat and over 450 due to cold. In the predictions, as Minimum Mortality Temperature (MMT) went up, the contribution of heat to mortality slightly decreased, and cold temperature played a more important role. By considering the risk reduction due to adaptation, the contribution of heat in mortality slightly and insignificantly decreased. Conclusion The results showed that although low temperatures will contribute to temperature-related mortality in the future, but heat will be a stronger risk factor for mortality, especially if adaptation is low.

Extremely low frequency electromagnetic fields have been classified as a possible human carcinogen by the International Agency for Research on Cancer and this has raised some concern about its health effects on employees extensively exposed to these fields at thermal power plants. In this study, the effect of using vitamin E and C supplements have been examined on employees working at a thermal power plant. In this randomized controlled, double-blind clinical trial, 81 employees from different parts of the thermal power plant were enrolled between July and November 2017, and divided into four groups: Group 1 received vitamin E (400 units/day), Group 2: vitamin C (1000 mg/day), Group 3: vitamin E + C and Group 4: no intervention. DNA damage was measured in peripheral blood lymphocytes using comet assay and apoptosis, using flow cytometry. Based on the results, tail intensity and tail length in the vitamin E group, and all comet assay indices in the vitamin E + C and vitamin C groups (except DNA damage index) significantly decreased after the intervention, while the comet assay indices did not change significantly in the control group. None of the flow cytometry indices including early apoptosis, late apoptosis and necrosis changed after intervention in either group. The use of antioxidant vitamins such as E and C, can increase the activity of the non-enzymatic antioxidant defense system, and protect DNA from damage caused by exposure to extremely low frequency magnetic fields. But, taking these vitamins has no effect on apoptosis. It seems that consumption of vitamin E affected all investigated comet assay indices and can be probably considered as the best intervention.

Concerning the high volume of wastewater containing dye in Iran and its adverse effects, it is necessary to develop scientific solutions for treating these wastewaters. The aim of this study was to evaluate the efficiency of the alumina-coated multi-walled carbon nanotubes in removing the Reactive Red 198 (RR 198) and Blue 19 (RB 19) dyes. Synthetic samples including dye with different concentrations were prepared. These samples were put in contact with different contents of alumina/multi-walled carbon nanotubes, in different pH values, in different contact times, different temperatures and the presence of sodium sulfate or sodium carbonate. The optimum pH, dye concentration and temperature for removal of the two dyes was 3, 50 mg l−1 and 25 °C, respectively. The optimum adsorbent dose for removal the RR 198 dye was 0.5 g l−1 and for Blue 19 was 0.4 g l−1. The optimum contact time for RR 198 was 150 min and RB 19 was 180 min. In this condition, maximum removal efficiency for RR 198 and RB 19 was 91.54% and 93.51%, respectively. The adsorption study was analyzed kinetically, and the results revealed that the adsorption fitted a pseudo-second order kinetic model. According to these results alumina/multi-walled carbon nanotubes can effectively remove RR 198 and RB 19 from aqueous solutions.

Iran has a high traffic fatality rate and a substantial proportion of those killed on the road are adolescents. The aim of the present study was to examine the relationship between dimensions of religiosity and the on-road behaviour of adolescents as pedestrians, cyclists and other non-driving activities. A total of 1111 students attending secondary schools in Tehran (Iran) completed the Adolescent Road User Behaviour Questionnaire (ARBQ) and the Duke University Religion Index (DUREL). This study found that adolescents who participated less often in private religious activities were more likely to be: male, have relatives or friends who had been killed in a road collision, previously involved in a road crash themselves and engaged more often in dangerous playing on the road. Adolescents reporting higher levels of religious attendance and intrinsic religiosity were more likely to be: male, without a traffic accident history, younger, from public schools, studying at schools in large urban areas and more frequently engaged in planned protective behaviours. Adolescents with higher involvement in intrinsic religiosity tended to be those: without an accident history, who did not have relatives or friends that had been killed in a crash and who engaged less frequently in unsafe road crossing behaviour. The findings of this study indicate that the different dimensions of religiousness are related to adolescents’ behaviour on the road. Thus, it appears that religion may have a role to play in improving the road safety of adolescents in Iran.

Electricity generation from microbial fuel cells which treat food processing wastewater was investigated in this study. Anaerobic anode and aerobic cathode chambers were separated by a proton exchange membrane in a two-compartment MFC reactor. Buffer solutions and food industry wastewater were used as electrolytes in the anode and cathode chambers, respectively. The produced voltage and current intensity were measured using a digital multimeter. Effluents from the anode compartment were tested for COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity. The maximum current density and power production were measured 527mA/m(2) and 230mW/m(2) in the anode area, respectively, at operation organic loading (OLR) of 0.364g COD/l.d. At OLR of 0.182g COD/l.d, maximum voltage and columbic efficiency production were recorded 0.475V and 21%, respectively. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO4 and alkalinity were 86, 79, 73, 18, 68, 62, 30 and 58%, respectively. The results indicated that catalysts and mediator-less microbial fuel cells (CAML-MFC) can be considered as a better choice for simple and complete energy conversion from the wastewater of such industries and also this could be considered as a new method to offset wastewater treatment plant operating costs.