Assessment of burden of disease induced by exposure to heavy metals through drinking water at national and subnational levels in Iran, 2019.

The burden of disease attributable to exposure to heavy metals via drinking water in Iran (2019) was assessed at the national and regional levels. The non-carcinogenic risk, carcinogenic risk, and attributable burden of disease of heavy metals in drinking water were estimated in terms of hazard quotient (HQ), incremental lifetime cancer risk (ILCR), and disability-adjusted life year (DALY), respectively. The average drinking water concentrations of arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and nickel (Ni) in Iran were determined to be 2.3, 0.4, 12.1, 2.5, 0.7, and 19.7 µg/L, respectively, which were much lower than the standard values. The total average HQs of heavy metals in drinking water in the entire country, rural, and urban communities were 0.48, 0.65 and 0.45, respectively. At the national level, the average ILCRs of heavy metal in the entire country were in the following order: 1.06 × 10-4 for As, 5.89 × 10-5 for Cd, 2.05 × 10-5 for Cr, and 3.76 × 10-7 for Pb. The cancer cases, deaths, death rate (per 100,000 people), DALYs, and DALY rate (per 100,000 people) attributed to exposure to heavy metals in drinking water at the national level were estimated to be 213 (95% uncertainty interval: 180 to 254), 87 (73-104), 0.11 (0.09-0.13), 4642 (3793-5489), and 5.81 (4.75-6.87), respectively. The contributions of exposure to As, Cd, Cr, and Pb in the attributable burden of disease were 14.7%, 65.7%, 19.3%, and 0.2%, respectively. The regional distribution of the total attributable DALY rate for all heavy metals was as follows: Region 5> Region 4> Region 1> Region 3> Region 2. The investigation and improvement of relatively high exceedance of As levels in drinking water from the standard value, especially in Regions 5 and 3 as well as biomonitoring of heavy metals throughout the country were recommended.

Effect of portable air purifier on indoor air quality: reduced exposure to particulate matter and health risk assessment.

We sought to investigate the impact of air purifiers in the removal of particular matter (PM)10, PM2.5, PM1, and particle number concentration (PNC) in the indoor air of dormitories located at Iran's largest medical university, Tehran University of Medical Sciences. Twelve rooms were selected and randomly assigned to two rooms: sham air purifier system deployed room (SR) and true air purifier system deployed room (TR). All study samples were drawn simultaneously from assigned rooms using portable GRIMM dust monitors for 24 h. The PM monitors of air were positioned in the middle of each room next to the air purifier at the height of the breathing zone (1.5 m in height). The mean PM10, PM2.5, PM1, and PNC removal efficiency in rooms with and without a smoker were measured to be 40.7 vs 83.8%, 31.2 vs 78.4%, 29.9 vs 72.3%, and 44.3 vs 75.6%, respectively. The results showed that smoking is an important influencing factor on the indoor air quality; smoking lowered the removal efficiency of PM10, PM2.5, PM1, and PNC by 43%, 47%, 43%, and 31%, respectively. An air purifier could decline the PM10 and PM2.5 even lower than the WHO 24-h guideline level in non-smoker rooms. This study revealed that using household air purifiers in rooms with smokers and non-smokers significantly reduces the non-carcinogenic risks of exposure to PM10 and PM2.5.

Air pollution exposure and mammographic breast density in Tehran, Iran: a cross-sectional study.

BACKGROUND: Air pollution is one of the major public health challenges in many parts of the world possibly has an association with breast cancer. However, the mechanism is still unclear. This study aimed to find an association between exposure to six criteria ambient air pollutants (PM2.5, PM10, SO2, NO2, O3, and CO) and mammographic breast density (MBD), as one of the strongest predictors for developing breast cancer, in women living in Tehran, Iran. METHODS: Participants were selected from women attending two university hospitals for screening mammography from 2019 to 2021. Breast density was rated by two expert radiologists. Individual exposures to 3-year ambient air pollution levels at the residence were estimated. RESULTS: The final analysis in 791 eligible women showed that low and high breast density was detected in 34.8 and 62.2 of participants, respectively. Logistic regression analysis after considering all possible confounding factors represented that an increase in each unit of NO2 (ppb) exposure was associated with an increased risk of breast density with an OR equal to 1.04 (95CI: 1.01 to 1.07). Furthermore, CO level was associated with a decreasing breast density (OR = 0.40, 95CI = 0.19 to 0.86). None of the other pollutants were associated with breast density. CONCLUSION: Higher MBD was associated with an increased level of NO2, as a marker of traffic-related air pollution. Furthermore, CO concentration was associated with a lower MBD, while other criteria air pollutants were not related to MBD. Further studies are needed to evaluate the association between ambient air pollutants with MBD.

Short-term effects of exposure to air pollution on biophysical parameters of skin in a panel of healthy adults.

Little research on impact of air pollution on human skin is available. We aimed to clarify the association between acute exposure to criteria air pollutant with biophysical characteristics of the skin. We followed a panel of 20 volunteers free of any skin diseases in skin evaluation study in Tehran, Iran from April 2017 to April 2018. Two distinct body parts including middle forehead and inside the right upper arm were evaluated at six time periods. The associations of the weighted averages of personal exposure to air pollutants at 24 hours up to 6 days, and multiday average before the skin assessment with biophysical characteristics of normal skin including sebum content, hydration, transepidermal water loss (TEWL), erythema index, melanin index, pH, temperature, friction, and elasticity were assessed in a random intercept linear mixed effects modeling approach. We observed significant positive association for the arm sebum content with exposure to PM2.5 , and SO2 ; the arm and forehead TEWL with NO2 , the arm and forehead friction with O3 , and forehead hydration with PM2.5 and PM10 in early lags. We found significant negative association for the arm melanin index, elasticity, and erythema index with exposure to O3 ; and forehead elasticity with PM2.5 and PM10 . Our results provided some evidence that short-term exposure to particulate and gaseous air pollutants have detrimental effects on biophysical and biomechanical properties of skin. The association varied across body area and depended on pollutant type.

Prenatal urinary concentrations of environmental phenols and birth outcomes in the mother-infant pairs of Tehran Environment and Neurodevelopmental Disorders (TEND) cohort study.

Daily exposure to environmental phenols can lead to potential undesirable effects on the health of pregnant women and fetuses. The present study is aimed to evaluate the relationship between maternal urinary concentrations of phenols in pregnancy and anthropometric birth outcomes. The studied population comprised of 189 pregnant women participating in the Tehran Environment and Neurodevelopmental Disorders (TEND) prospective cohort study, which had been ongoing since March 2016 in some hospitals and health care delivery centers in Tehran, Iran. Concentrations of bisphenol-A, triclosan, 4-nonylphenol, and parabens were determined in spot urine samples of pregnant mothers in the first trimester. Weight, length, and head circumference at birth were also extracted from the mothers' delivery files. Multivariable linear regression was used to examine the relationship between log-concentrations of phenols and birth outcomes. When we analyzed all samples regardless of neonates' gender, none of the urinary concentrations of phenols were associated with weight and length at birth. Indeed, in sex-stratified adjusted models, one log-unit increase of butylparaben was related to a 283.6 g (95% CI: 23, 544) increase in boys' birth weight. Prenatal urinary concentration of triclosan and propylparaben was respectively related to a decrease of 4.8 cm (95% C: -8.5, -1.1) in boys' length and 0.9 cm (95%CI: -1.8, -0.04) in girls' length. In the adjusted models for estimating the changes in head circumference, one log-unit increase of triclosan, methylparaben, and butylparaben led to a reduction of 1.6 cm (95% CI: -3.17, 0.03), increase of 0.8 cm (95% CI: -0.01, 1.6) and 0.7 cm (95% CI: 0.08, 1.4) in head circumference at birth respectively. Our results suggested that prenatal triclosan and parabens exposure might be associated with head circumference at birth. Furthermore, we observed a sexually dimorphic pattern between maternal triclosan and parabens exposure during pregnancy and fetal growth. However, these findings must be interpreted while taking into account the limitations of this study.

Sensitivity of Crosswise Model to Simplistic Selection of Nonsensitive Questions: An Application to Estimate Substance Use, Alcohol Consumption and Extramarital Sex Among Iranian College Students.

BACKGROUND: Nonrandomized response (NRR) models are a new generation of surveys for sensitive issues. This study aims to evaluate the validity of estimates from the crosswise model (as one of the efficient models) through employing different response probabilities of nonsensitive questions. METHODS: This cross-sectional study was conducted during October and November 2015 among 1777 students of Tabriz University of Medical Sciences. Estimates of monthly alcohol consumption, and at least one instance of illicit drug use and extramarital sex over the last year were determined using direct questioning (DQ) and the Crosswise model (CM). In the last model, the probability of positive response to the nonsensitive questions was determined by using five different methods: uniform distribution (I), Benford's law (II), and estimations based on data from three other studies (III, IV, V). RESULTS: Crosswise estimates of sensitive behaviors with different probabilities of a positive response to nonsensitive questions differed significantly. For example, estimates of history of using illegal opioids at least once in the last year among men varied significantly from 5.0% to 16.1% with different crosswise models based on the probability of being born in Spring using method I (0.250), III (0.287), IV (0.248), and V (0.310). The model based on Benford's law (II) was applied to estimate alcohol and cannabis consumption, and its estimates showed significant discrepancy with results of crosswise models I and V. CONCLUSION: Estimates from crosswise model is highly sensitive to the response probability of nonsensitive questions. It seems that if this question is not selected carefully, the mentioned models will provide overestimates or underestimates, and the more-is-better hypothesis is not always valid. To achieve valid estimates, the exact probability of a positive response to the nonsensitive question must be known for the studied population.

Unusual Route of Buprenorphine Administration: An Alternative Approach for Bypassing Adverse Drug Reactions.

Tramadol abuse is a critical and growing health concern in Asia. In Iran, tramadol abuse arises most commonly as a result of self-medicating that leads to tramadol dependence. Buprenorphine, a partial agonist of mu opioid receptors approved for the treatment of tramadol dependence, is administered sublingually due to its extensive first-pass metabolism and resulting low oral bioavailability. A 50-year-old man presenting with tramadol dependence after self-medicating for chronic low back pain experienced adverse reactions to a minimal dosage (0.8 mg) of sublingual buprenorphine. He was treated successfully with a modified protocol composed of swallowing sublingual tablets (0.2 mg/day initially, which increased to 0.2 mg every 12 hours during maintenance therapy). This unusual case suggests that swallowing buprenorphine sublingual tablets may prevent adverse effects and reduce the rate of treatment dropout.

Spatial and temporal variability of fluoride concentrations in groundwater resources of Larestan and Gerash regions in Iran from 2003 to 2010.

There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in groundwater resources of Larestan and Gerash regions in Iran were analyzed from 2003 to 2010 using a geospatial information system and the Mann-Kendall trend test. The mean concentrations of fluoride for the 8-year period in the eight cities and 31 villages were 1.6 and 2.0 mg/l, respectively; the maximum values were 2.4 and 3.8 mg/l, respectively. Spatial, temporal, and spatiotemporal variability of fluoride in overall groundwater resources were relatively constant over the years. However, results of the Mann-Kendall trend test revealed a monotonic trend in the time series of one city and 11 villages for the 8-year period. Specifically, one city and three villages showed positive significant Kendall's Tau values, suggesting an upward trend in fluoride concentrations over the 8-year period. In contrast, seven villages displayed negative significant Kendall's Tau values, arguing for a downward trend in fluoride concentrations over the years. From 2003 to 2010, approximately 52 % of the Larestan and Gerash areas have had fluoride concentrations above the maximum permissible Iranian drinking water standard fluoride level (1.4 mg/l), and about 116,000 people were exposed to such excess amounts. Therefore, our study supports for a close monitoring of fluoride concentrations from health authorities in monthly intervals, especially in villages and cities that showed positive trend in fluoride concentrations. Moreover, we recommend simultaneous implementation of cost-effective protective measures or interventions until a standard fluoride level is achieved.

Knowledge, Attitude, and Practice of Clerical Students with Respect to HIV/AIDS in Iran, 2011.

In this study, knowledge and attitude of Iranian clerical students toward HIV and AIDS was assessed. Through a cross-sectional study, 367 clerical students were surveyed, in convenience sampling method, in the Qom seminary in 2011, utilizing a self-administered structured questionnaire. The questionnaire was piloted on 20 clerical student volunteers, internal consistency measured with Cronbach's alpha was 0.89. Participants' scores of knowledge and attitude were calculated out of 100. The level of knowledge in 37.33 % of participants was good (scores >80), whereas 46.05 and 16.62 % had moderate (40 < scores ≤ 80) and poor (scores ≤40) levels of knowledge, respectively. The mean score of knowledge and attitude was 58.29 (95 % CI 56.11-60) and 77.26 (95 % CI 75.92-78.59) out of 100, respectively. A significant correlation was observed between level of knowledge and attitude (r = 0.33, P < 0.001). Knowledge score appeared to be significantly higher in women compared to men (p = 0.04). With an increase in age, the level of knowledge significantly decreased (r = -0.10, P = 0.02). We could also detect a statistically significant relationship between attending educational courses on HIV/AIDS and inclusion of HIV/AIDS topics in the individual's sermons (P < 0.001). Although clerical students had shown some sort of positive attitudes toward HIV, their knowledge still needs to be improved to enable them to deliver more accurate information to the community during the course of their speeches. Having HIV-related courses as part of their curriculum or aside may contribute a lot to this.

Estimating the prevalence of illicit drug use among students using the crosswise model.

OBJECTIVE: The aim of our study is to compare the prevalence of illicit drug use estimated through a technique referred to as the "crosswise model" (CM) with the results from conventional direct questioning (DQ). METHOD: About 1,500 students from Tehran University of Medical Sciences 2009-2010 were first interviewed by DQ and, then three months later, by the CM. RESULT: The CM yielded significantly higher estimates than DQ for lifetime prevalence of use of any illicit drug (CM = 20.2%,DQ = 3.0%, p < .001) and for lifetime prevalence of use of opium or its residue (CM = 13.6%, DQ = 1.0%, p < .001). Also, for use of any illicit drug in the last month and use of opium or its residue in the last month, the CM yielded higher point estimates than DQ, although these differences were not significant (any drug: CM = 1.5%, DQ = 0.2%, p = .66; opium: CM = 3.8%, DQ = 0.0%, p = .21). CONCLUSION: Our findings suggest that the CM is a fruitful data collection method for sensitive topics such as substance abuse.

Exposure to ambient gaseous air pollutants and adult lung function: a systematic review.

Exposure to hazardous air pollutants is identified as most obvious premature mortality factors in the world. Numerous epidemiological studies have estimated exposure to air pollutants may cause pulmonary toxicity and the incidence of respiratory diseases including chronic obstructive pulmonary disease (COPD), chronic bronchitis and asthma. The currently research was performed to evaluation the association between gaseous pollutants and lung function in healthy adults. Articles related to this study were selected from researches of Scopus, PubMed, and Web of Science databases. A total of 2,644 articles were retrieved and 39 records were reviewed after removing duplicates and excluding irrelevant studies. The result of this systematic review indicated that there is some evidence on decreasing lung function with exposure to gaseous air pollutants (NO2, SO2, and O3) which can have negative effects on human health. Although according to the evidence changes in lung function are mostly linked to the exposure to environmental pollutants including CO, O3, NO2 and SO2, the results should be interpreted with caution considering some following issues discussed in this review. Therefore, further studies are required considering well-designed studies in large scales to strengthen the evidence.

Burden of diseases attributable to second-hand smoke exposure in Iran adolescents from 2009 to 2020.

Exposure to second-hand smoke (SHS) is prevalent in many countries, but the problem's scope is poorly understood globally, especially in developing countries. We aimed to estimate SHS exposure and its national and subnational burden of diseases in Iran, the second-largest country in the Middle East, during 2009-2020. The burden of diseases from SHS was estimated as disability-adjusted life years (DALYs) for adolescents (10-18) year's non-smokers. Using comparative risk assessment methodologies, the calculations were based on disease-specific relative risk estimates with national and subnational SHS exposure data, and the uncertainty and sensitivity analysis was performed. The results of study showed that the trend of exposure to SHS is increasing in Iran. The highest DALY was related to lower respiratory infection (LRI), asthma, and otitis media, respectively. The national average asthma burden (DALY/100,000) has increased from 17.4 (11.8_23.9) in 2009 to 21.3 (13.9_30) in 2020, LRI decreased from 25.8 (21.5_30.2) to 19.8 (16.7_23.1), and national average burden of otitis media (DALY/100,000) has increased from 3.1(1.9_4.6) to 3.9(2.4_5.6). The increasing trend of otitis media and asthma DALYs attributable to SHS exposure in Iran requires more attention from policymakers to protect the population.

Effect of Early Bacillus Calmette-Guerin Vaccination of Pediatric Severe Combined Immunodeficiency Patients on the Outcome of Hematopoietic Stem Cell Transplantation Using a Reduced-Intensity Conditioning Regimen.

The eminence of Bacillus Calmette-Guerin (BCG) vaccine in newborn vaccination programs has been conspicuous throughout the years, especially in low-income developing countries where tuberculosis is prevalent; however, application of the BCG vaccine is not without constraints, especially in patients afflicted with immunodeficiency diseases, such as severe combined immunodeficiency (SCID). The present study aimed to evaluate whether the administration of BCG vaccine at birth could improve the outcomes of hematopoietic stem cell transplantation (HSCT) in pediatric patients with SCID. In this study, 30 SCID patients who underwent HSCT using a reduced-intensity conditioning regimen (RIC) were followed-up for 2 years post-HSCT. The outcomes of HSCT were evaluated in both non-BCG-vaccinated patients (n = 12) and BCG-vaccinated patients (n = 18). Our results show a higher incidence of acute graft-versus-host disease (aGVHD), but not of chronic GVHD, in the BCG-vaccinated patients, and a similar overall survival (OS) rate in the 2 groups. We speculate that the similar OS rate in the 2 groups, despite the risk of BGC vaccination, was because this group received an RIC conditioning regimen. There was no other difference between the 2 groups. Considering the effect of the BCG vaccine on HSCT outcome, we suggest that the administration of BCG vaccine be deferred until age 3 months so that APT testing without the interference of maternal antibodies can be performed. However, this study could benefit from a larger cohort to further validate our findings, as the possible reason for some factors not being statistically significant was our small sample size.

Ambient Air Quality Standards and Policies in Eastern Mediterranean Countries: A Review.

Objectives: National ambient air quality standards (NAAQS) are critical tools for controlling air pollution and protecting public health. We designed this study to 1) gather the NAAQS for six classical air pollutants: PM2.5, PM10, O3, NO2, SO2, and CO in the Eastern Mediterranean Region (EMR) countries, 2) compare those with the updated World Health Organizations Air Quality Guidelines (WHO AQGs 2021), 3) estimate the potential health benefits of achieving annual PM2.5 NAAQS and WHO AQGs per country, and 4) gather the information on air quality policies and action plans in the EMR countries. Methods: To gather information on the NAAQS, we searched several bibliographic databases, hand-searched the relevant papers and reports, and analysed unpublished data on NAAQS in the EMR countries reported from these countries to the WHO/Regional office of the Eastern Mediterranean/Climate Change, Health and Environment Unit (WHO/EMR/CHE). To estimate the potential health benefits of reaching the NAAQS and AQG levels for PM2.5, we used the average of ambient PM2.5 exposures in the 22 EMR countries in 2019 from the Global Burden of Disease (GBD) dataset and AirQ+ software. Results: Almost all of the EMR countries have national ambient air quality standards for the critical air pollutants except Djibouti, Somalia, and Yemen. However, the current standards for PM2.5 are up to 10 times higher than the current health-based WHO AQGs. The standards for other considered pollutants exceed AQGs as well. We estimated that the reduction of annual mean PM2.5 exposure level to the AQG level (5 µg m-3) would be associated with a decrease of all natural-cause mortality in adults (age 30+) by 16.9%-42.1% in various EMR countries. All countries would even benefit from the achievement of the Interim Target-2 (25 µg m-3) for annual mean PM2.5: it would reduce all-cause mortality by 3%-37.5%. Less than half of the countries in the Region reported having policies relevant to air quality management, in particular addressing pollution related to sand and desert storms (SDS) such as enhancing the implementation of sustainable land management practices, taking measures to prevent and control the main factors of SDS, and developing early warning systems as tools to combat SDS. Few countries conduct studies on the health effects of air pollution or on a contribution of SDS to pollution levels. Information from air quality monitoring is available for 13 out of the 22 EMR countries. Conclusion: Improvement of air quality management, including international collaboration and prioritization of SDS, supported by an update (or establishment) of NAAQSs and enhanced air quality monitoring are essential elements for reduction of air pollution and its health effects in the EMR.

Assessing capabilities of conducted ambient air pollution health effects studies in 22 Eastern Mediterranean countries to adopt air quality standards: a review.

Purpose: The Eastern Mediterranean Region (EMR) countries suffer from exposure to high levels of ambient air pollutants due to dust storms and have unique climatic as well as topographic and socio-economic conditions which lead to adverse health effects on humans. The purpose of the review was to evaluate the quantity and quality of published articles on air pollution and health-based studies in 22 EMR countries to determine if they can be applied to adopting air quality standards. Methods: We designed a review based on a broad search of the literature in the Scopus, PubMed, and web of science (WOS) databases published from January 1, 2000, to January 2, 2022, using combinations of the following relevant terms: air pollution, health, and EMR countries. The generic eligibility criteria for this review were based on the population, exposure, comparator, outcome, and study design (PECOS) statement. Results: The search results showed that following the PRISMA approach, of 2947 identified articles, 353 studies were included in this review. The analysis of the types of studies showed that about 70% of the studies conducted in EMR countries were Health Burden Estimation studies (31%), Ecological and time trend ecological studies (23%), and cross-sectional studies (16%). Also, researchers from Iran participated in the most published relevant studies in the region 255 (~ 63%) and just 10 published documents met all the PECOS criteria. Conclusion: The lack of sufficient studies which can meet the PECOS appraising criteria and the lack of professionals in this field are some of the issues that make it impossible to use as potential documents in the WHO future studies and adopt air quality standards. Supplementary Information: The online version contains supplementary material available at 10.1007/s40201-023-00862-1.

Evaluation of the relationship between psychological distress and sleep problems with annoyance caused by exposure to environmental noise in the adult population of Tehran Metropolitan City, Iran.

Purpose: The aim of this study was to investigate the association between the psychological distress and sleep problems with environmental noise annoyance in adult population. Methods: This is a cross-sectional study on 822 adult population of Tehran City in 2016. Integrated cluster stratified random sampling and Kish grid method were used. Noise annoyance, the day-night average sound level (Ldn), nighttime average sound level (Lnight), and daytime average sound level (Lday) were selected as noise exposure indicators. The prevalence of psychological distress and sleep problems were assessed using the Kessler Psychological Distress Scale (K10) and the PSQI questionnaire, respectively. Multiple logistic regression analysis was applied for data analysis. Results: Among the participants 46.03%% were exposed to a sound level higher than the daytime standard level (55 dB) and 84.6% were exposed to a level higher than the nighttime standard limit (45 dBA). According to the results, 49% of the subjects had poor sleep quality and 66% were highly sensitive to noise. In addition, 17.73% had a high risk of mental disorders and 16.48% were found to have a mild risk of mental disorders. There was found a statistically significant association between psychological distress and the noise annoyance at home (OR = 1.3 CI 95% (1.17-1.44)) and at work environment (OR = 1.18 CI 95% (1.08-1.28)). Conclusion: The findings indicated that the study population was highly sensitive to noise. In addition, the relatively high percentage of people who exposed to non-standard levels of sound indicates that this exposure has the potential to cause physical and mental consequences among them.

Burden of diseases attributed to traffic noise in the metropolis of Tehran in 2017.

Although road traffic noise is the most important source of environmental noise emission in large cities, little is known about health burden. The present study was conducted to estimate the burden of diseases attributed to traffic noise in the metropolis of Tehran in 2017. Using noise maps provided by the municipality of Tehran, we calculated population exposure distribution in term of Ldn and Lnight and the number of DALYs lost due to ischemic heart disease, hypertension, high sleep disturbance, annoyance and stroke endpoints based on the World Health Organization Environmental Noise Guidelines for the European Region. We applied published dose-response functions to estimate the traffic noise burden for high sleep disturbance and annoyance. We estimated 61,284 DALYs or 697 DALYs per 100,000 population attributed to traffic noise in Tehran for the reference year 2017. Highly sleep disturbance with a share of 58.74% of the DALYs was recognized as the most important contributor of disease burden, and noise annoyance with a share of 23.12% was ranked next. Ischemic heart disease (11.71%), stroke (5.12%), and hypertension (1.31%) were ranked third to fourth, respectively, in terms of the burden of disease caused by environmental noise. A considerable fraction of the population of Tehran lives in areas with an environmental noise higher than the standard level. The findings showed that traffic noise pollution is an important environmental risk factor in Tehran imposes the greatest burden on the community, mainly through highly sleep disturbance and noise annoyance endpoints.

Development and validation of an individual job performance questionnaire (IJPQ).

BACKGROUND: Developing reliable tools to tap into all the behavioral dimensions of individual job performance and identifying the right sub-dimensions is necessary for both research and practice. OBJECTIVE: This study aimed at developing and validating an IJPQ that addresses shortcomings of existing questionnaires. METHODS: After a comprehensive systematic literature review, a framework consisting of four dimensions, including task performance (TP), contextual performance (CP), counterproductive work behavior (CWB), and adaptive performance (AP) was structured for measuring IJP. As well, 45 sub-dimensions were identified for measuring IJP's dimensions. Content and face validity were evaluated, and item impact score (IS), content validity index (CVI), Kappa, and content validity ratio (CVR) were calculated. For reliability and confirmatory factor analysis (CFA), 525 workers completed the validated questionnaire and Cronbach alpha and goodness of fit indexes were determined, respectively. RESULTS: Of the 62 items generated to measure dimensions, 53 were approved. Based on item-level CVI, of the 53 items, only 45 items were accepted. Finally, the results of item level CVR led to the extraction of 27 questions to evaluate IJP. The obtained scale level CVI and scale level CVR were 0.91 and 0.68, respectively. Based on the results obtained from 525 Iranian workers, values of Cronbach's Alpha, X2/df, RMSEA, and P-value were in the acceptable range. CONCLUSIONS: Conclusively, a questionnaire containing 20 items was developed and validated for measuring IJP of Iranian worker's culture. The four dimensions of TP, CO, CWB, and AP consisted of 6, 5, 5, and 4 items each, respectively. Overall, IJPQ is a theory-based, reliable, and valid instrument for assessing job performance.

Design and ergonomic assessment of a passive head/neck supporting exoskeleton for overhead work use.

Overhead work is an important risk factor associated with musculoskeletal disorders of the neck and shoulder region. This study aimed to propose and evaluate a passive head/neck supporting exoskeleton (HNSE) as a potential ergonomic intervention for overhead work applications. Fourteen male participants were asked to perform a simulated overhead task of fastening/unfastening nut in 4 randomized sessions, characterized by two variables: neck extension angle (40% and 80% of neck maximum range of motion) and exoskeleton condition (wearing and not wearing the HNSE). Using the HNSE, significantly alleviated perceived discomfort in the neck (p-value = 0.009), right shoulder (p-value = 0.05) and left shoulder (p-value = 0.02) and reduced electromyographic activity of the right (p-value = 0.005) and left (p-value = 0.01) sternocleidomastoid muscles. However, utilizing the exoskeleton caused a remarkable increase in right (p-value = 0.04) and left (p-value = 0.05) trapezius electromyographic activities. Performance was not significantly affected by the HNSE. Although the HNSE had promising effects with respect to discomfort and muscular activity in the static overhead task, future work is still needed to investigate its effect on performance and to provide support for the generalizability of study results.