Geospatial analysis for environmental noise mapping: A land use regression approach in a metropolitan city.

Environmental noise can lead to adverse health outcomes. Understanding the spatial variability of environmental noise is crucial for mitigating potential health risks and developing influential urban strategies for reducing noise levels. This study aimed to measure noise levels and develop a land use regression (LUR) model to determine the spatial variability of environmental noise in Shiraz, Iran. A grid-based technique was used to establish 191 noise measurement sites (summer) across the city to generate the LUR model based on two noise metrics: Lden and Lnight. Leave-one-out cross-validation (LOOCV) and 38 additional measurement sites (winter) were used for the LUR model assessment. The mean values of Lden and Lnight during summer were 68.20 (±8.05) and 58.95 (±9.55), respectively, while during winter, the corresponding values were 69.46 (±5.46) and 58.81 (±6.79). The LUR models explained 67% and 65% of the spatial variability in Lden and Lnight, respectively. LOOCV analysis demonstrated R2 values of 0.64 and 0.61. Moreover, findings indicated mean absolute error (MAE) values of 3.96 dB(A) for Lden and 4.74 dB(A) for Lnight. Validation based on an additional set of 38 measurement sites revealed R2 values of 0.62 for both Lden and Lnight, with MAE of 2.78 and 3.31, respectively. In addition, the adjusted R2 values were 0.54 and 0.53. The results indicated no significant temporal variations between summer and winter. The results revealed that road-related variables significantly influenced noise levels. Moreover, the results indicated that Lden and Lnight levels were higher than the World Health Organization recommendations for exposure to road traffic noise. The results of our study showed that the LUR modeling approach based on geographical predictors is an effective tool for assessing changes in ambient noise levels in other cities in Iran and around the globe.

Strategic analysis of Iran's climate resilient health system.

INTRODUCTION: Climate change is a long-term systematic climate variability caused by human activities that alters the composition of the global atmosphere. Health systems should be adaptive and resilient to climate change. Hence, this research aimed to strategically analyze the resilience of Iran's health system to climate change. METHOD: This study utilized a multiple methods approach. First, in-depth semi-structured interviews were conducted with 32 key climate change and health experts to identify the strengths, weaknesses, opportunities and threats of the Iranian health system's resilience to climate change. Purposeful and snowball sampling techniques were used to ensure maximum diversity among the participants. Then, a questionnaire was developed based on the findings of the first stage and was completed by 33 climate change and health experts. Finally, the strategic position of Iran's health system's resilience to climate change was determined using the internal - external factors matrix. FINDINGS: A total of 84 internal factors and 101 external factors were identified that affect the resilience of Iran's health system against climate change. The internal factors were categorized into seven dimensions (i.e., governance and leadership; health financing; health workforce; facilities, equipment and medicines; health information system; health services delivery, and key results). The external factors were categorized into six dimensions (i.e., political, economic, social, technological, environmental, and legal factors). The average score of internal and external factors were 2.47 and 2.12, out of 4 respectively. Iran's health system was found to be in the strategic position of V in terms of resilience to climate change. Therefore, precautionary strategies such as strengthening the climate resilience of healthcare facilities, promoting healthcare facilities' adaptation to climate change, public-private partnership, strengthening the health service delivery system, quality management and cost management, should be implemented to strengthen the resilience of Iran's health system to climate change. DISCUSSION: Iran's health system is facing significant weaknesses and challenges that have hindered its resilience to climate change. Iran's health system can better prepare and respond to the health impacts of climate change, and safeguarding the health and well-being of its population by addressing these challenges and implementing adaptive and resilience strategies.

Hidden health effects and economic burden of stroke and coronary heart disease attributed to ambient air pollution (PM2.5) in Tehran, Iran: Evidence from an assessment and forecast up to 2030.

Air pollution is one of the main causes of global disease burden, especially in low-income and middle-income countries. Estimation of the current situation and prediction of the future health effects of death and incidence of stroke and coronary heart disease (CHD) attributed to PM2.5 were done using BenMAP-CE software. Estimating and forecasting the economic burden of these diseases were done in 4 scenarios: Stability of the current PM2.5 concentration, annual 10 % reduction of PM2.5 concentration, reduction to 5 µg/m3, and reduction to 12 µg/m3, with three approaches for calculating the economic burden in mortality costs, including the human capital(HC), years of life lost(YLL) and value of statistical life(VSL) was performed. With the stability of the PM2.5 concentration, the economic burden of stroke attributed to PM2.5 with the approach of calculating the cost of death with the HC, the YLL, and VSL will reach from 64, 82 and 172 million USD in 2020-849, 1120 and 2703 million USD in 2030 and these costs for CHD in the mentioned approaches of calculating the cost of death will reach respectively from 499, 568 and 898 million USD in 2020-7096, 8088, and 13,621 million USD in 2030. We find that the morbidity economic burden (including direct, indirect, and intangible costs) of stroke compared to the cost of death with the HC, and YLL approaches are 67.58 times, 3.15 times respectively, and in the VSL approach is 47.32 % of stroke death cost. Also, the costs of CHD morbidity economic burden compared to the cost of death in the method of calculating the cost of death with the HC, YLL, and VSL approaches are 42.09, 7.25, and 1.16 times, respectively. This study provides comprehensive baseline information for health policymakers to understand the benefits of air pollution control policies globally, especially in LMICs.

A systematic review and meta-analysis on dropout of infertility treatments and related reasons/factors.

Dropout of infertility treatments is a common phenomenon and many patients avoid continuing infertility treatments. Determining the total rate of treatment dropout, and related factors was the objective of the present systematic review and meta-analysis study. We performed an electronic literature search in Web of Science, Scopus, Embase, Cinhal, ProQuest and Medline databases and a manual search in Google scholar by using a set of Standard keywords. We included descriptive studies in English or Persian, from August 2000 to 2019. Finally, we extracted data of 25 papers for systematic review and 11 papers for meta-analysis. Data analysed by RevMan software. The results of the meta-analysis analysed by the random-effects model and studies heterogeneity analysed using the I2 calculation index. We tried to control high heterogeneity (because of the small amounts of p value and chi-square and large amount of I2) with statistical methods such as subgroup analysis and using random-effects model. The results showed that factors related to treatment, psychological and demographic/personal factors are the most common factors for dropout. It seems that educational and supportive programs on psychological, financial, therapeutic, demographic and personal factors can play an important role in reducing the incidence of infertility treatment's drop out before completing the course of treatment.

Assessment of hydrogeochemical characteristics and quality of groundwater resources in relation to risk of gastric cancer: comparative analysis of high- and low-risk areas in Iran.

The chemical quality of groundwater supplies in two high-risk area (HRA) and low-risk area (LRA) for gastric cancer in Iran was assessed through hydrogeochemical analysis and water quality indices. For this aim, Piper and Schoeller diagrams and water quality index (WQI) were applied. In addition, exposure to nitrate via drinking water and its corresponding risk were also assessed using Monte Carlo simulation technique. Data on physicochemical properties of groundwater resources were obtained from Iran Water Resources Management Company. Sampling and analysis of tap water for nitrate concentration were conducted in two cities of Shiraz (as a representative of LRA) and Ardabil (as a representative of HRA). According to Piper diagrams, the dominant hydrogeochemical facies of groundwater supplies in HRA and LRA were Na-HCO3 (43.75%) and Ca-HCO3 (41.77%), respectively. The predominant cations in groundwater resources of HRA were found to be Na+ (68.06%) and Ca2+ (31.94%). For LRA, the typical cations were in decreasing trend: Ca2+ (39.64%) > Mg2+ (18.35%) > Na+ (17.26%). For two areas, HCO3-, SO42- and Cl- were, respectively, the most frequent anions. Two-sample Wilcoxon test showed that there were statistically significant difference between two areas in terms of anions and cations concentrations (p value < 0.05). The mean of total hardness (Ca2+ + Mg2+) concentration of water supplies in LRA (528.1 mg/L) was higher than HRA (263.1 mg/L), whereas the mean of Na+ concentration was found to be lower in LRA (90.6 mg/L) compared with HRA (108.1 mg/L). The sum of nitrate intake and its risk in LRA was higher than HRA. WQI results showed that drinking water quality in HRA and LRA ranged from excellent to poor and most water resources were of a good quality class. Further studies are suggested to investigate the role of drinking water in the etiology of gastric cancer in Iran.

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.

The concentration of BTEX compounds and health risk assessment in municipal solid waste facilities and urban areas.

In this study, human exposure to benzene, toluene, ethylbenzene, xylenes (BTEX), along with their respective risk assessment is studied in four major units (n = 14-point sources) of the largest municipal solid waste management facilities (MSWF) in Iran. The results were compared with four urban sites in Tehran, capital of Iran. Workers at the pre-processing unit are exposed to the highest total BTEX (151 µg m-3). In specific, they were exposed to benzene concentrations of 11 µg m-3. Moreover, the total BTEX (t-BTEX) concentrations measured over the conveyor belt was 198 µg m-3 at most, followed by trommel (104), and active landfills (43). The mean concentration of ambient t-BTEX in Tehran is 100 µg m-3. On average, xylenes and toluene have the highest concentrations in both on-site and urban environments, with mean values of 24 and 21, and 41 and 37 µg m-3, respectively. Even though the non-carcinogenic risk of occupational exposure is negligible, BTEX is likely to increase the chance of carcinogenic risks (1.7E-05) for workers at the pre-processing unit. A definite carcinogenic risk of 1.3E-04, and non-carcinogenic effect, of HI = 1.6 were observed in one urban site. With the exception of the pre-processing unit, the citizens of Tehran had higher exposure to BTEX. Overall, BTEX concentrations in the largest MSWF of Iran remains an issue of public health concern.

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.

Prospective cohort study on the social determinants of health: Tehran University of Medical Sciences employees` cohort (TEC) study protocol.

BACKGROUND: In this study, the association between the social determinants of health (SDH) as well as other health risk factors and outcomes will be evaluated at different socioeconomic layers. METHODS/DESIGN: This is a prospective cohort study that was launched in January 2018 on Tehran University of Medical Sciences' employees. The initial enrolment phase will continue up to March 2021, or until a sample size of 5500 is reached. In addition to annual phone-calls, the participants will be followed thrice at 5-year intervals. Data are collected through blood and urine samples, complete physical examination, anthropometric evaluation, and the completion of questionnaires related to SDH, such as socioeconomic status and social capital, history of diseases, lifestyle (including, nutrition, physical activity, cigarette and hookah smoking), occupational exposures (including psychosocial factors at work and work-family conflicts), and different aspects of physical, mental and occupational health as health outcomes. The association between independent variables and health (objective or subjective) are examined using multiple models and by controlling the confounding effects. Moreover, the trend in lifestyle changes and its impact on health are evaluated. DISCUSSION: Our study will explore the key social determinants as well as other factors including socioeconomic status and social capital, history of diseases, lifestyle and occupational exposures that affect health. This will provide social and occupational health decision-makers and stakeholders with new and valuable evidence in an era in which we are witnessing huge changes in lifestyle.

Dropout of infertility treatments and related factors among infertile couples.

BACKGROUND: Dropout of infertility treatments is a global issue and many factors play role in this phenomenon. It is one of the most challenges in life of infertile couples. The purpose of this study was to determine dropout rate and related factors/reasons in the world and in Iran. METHODS: We will conduct a mixed method study with sequential exploratory design (systematic review, qualitative and quantitative phase). In the first stage a systematic review on dropout rate of infertility treatments and related factors will be done. In second stage (quantitative-qualitative study), a retrospective cohort study will be conducted on infertile couples to determine dropout rate of infertility treatments. The follow-up period to assess the discontinuation of treatment in patients, who have discontinued the treatment, will be considered 6 months after the treatment cessation. Data would be analyzed by descriptive statistics. We want to determine proportion and percentage of discontinuation rate among different groups with different causes of infertility. Then, we also will use Chi-square test to compare discontinuation rates among these groups. In qualitative section of second stage, semi-structured interviews would be performed with infertile female who had the history of infertility treatments failure. In this stage, participants will be selected using purposeful sampling method with maximum variation in terms of age, education, occupation, type of infertility, type of treatments, number of unsuccessful treatment and infertility duration. Data would be analyzed using conventional content analysis. DISCUSSION: Determining dropout rate and its related factors/reasons would be helpful for future studies to plan suitable interventions for supporting infertile couples. It also helps politicians to have a better understanding of infertility and its consequences on infertile couple's life. In today's world, infertility is a common phenomenon due to postponement of childbearing following the older age of marriage, tendency to reach higher educational level, economical problems and etc. Infertility brings many challenges and stresses to the individuals by itself and it is very hard to cope with. The problem gets worse, when it is associated with failure in treatments. Many of infertile couples cannot tolerate this failure and may decide to discontinue treatments before achieving pregnancy for ending many stressors which are associated with treatments. As we know, childbearing and having at least one child has important position in some societies such as Iranian culture; so ending the treatment before achieving optimal result may have some adverse consequences in the families such as divorce, remarriage, family conflicts, et. Absolutely many factors play role in dropout of infertility treatments, and many studies around the world have suggested many factors/reasons in dropout of infertility treatments, but there are still many gaps about this subject, especially among Iranian society. This study would be conducted in three consecutive stages, in the first stage; we will do a complete review of existing studies of the world to find out related factors/reasons of dropout in detail. In second stage, dropout rate of infertile couples (380 couples) after at least one unsuccessful cycle of treatment would be achieved by assessing medical records and telephone interview. Data of the first and second stage will help us to have better vision about the issue of dropout and would be used to construct a semi structured interview for the last stage. And finally in the third stage, reasons of dropout would be asked by an in depth interview from infertile couples. We hope the information from this study will help politicians better understand and plan for dropout of treatment.

Exposure to endotoxins and respiratory health in composting facilities.

The impact of bioaerosols in municipal solid waste management is nowadays identified as a growing health concern worldwide. In this study, exposure to endotoxin in composting facilities and its association with lung function and clinical symptoms was investigated in Tehran municipal solid waste management complex (Aradkooh) as one of the largest solid waste management facilities in the Middle East. Airborne endotoxins were collected between June and July 2019 and the concentrations were determined by Limulus Amebocyte Lysate (LAL) method. Healthy workers with no history of respiratory disease were recruited and data on clinical symptoms (cough, phlegm, wheezing, dyspnea, fatigue, headache, eye irritation, runny nose, runny eyes, and sore throat) was obtained by the modified American Thoracic Society questionnaire, and spirometric measurement was performed by an expert. The binary logistic regression test was used and adjusted for confounding variables. The results didn't show any difference in lung function parameters (FEV1, FVC, FEV1/FVC, PEF, FEF25-75%), and most of the respiratory symptoms despite a relatively high difference in the concentration of endotoxin observed in air samples of different locations. Only the increased risk of cough (OR 10.5, 95% CI: 2.4 to 44.8 in the moderately exposed group and 7.8, 95% CI: 1.6 to 39.1 in highly exposed ones), fatigue (OR 3.7, 95% CI: 1.2 to 11.7), and headache (OR 6.02, 95% CI: 1.4 to 24.5) were found in the exposed groups compared to controls after adjusting for age, active and passive smoking. However, findings of the study might be underestimated due to some issues including healthy worker effect, intra and intersubject variability, and self-reporting bias, thereby the results should be interpreted with caution. Although we did not find any relationship, due to the high concentrations of endotoxins observed in some sites, it is recommended to consider some possible prevention measures such as using personal protective equipment to reduce the exposure of workers at an acceptable level.

Association Between Leukocyte Telomere Length and Serum Concentrations of PCBs and Organochlorine Pesticides.

Exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) through food, water, and air occurred during the life, which may change telomere length (TL) in peripheral blood leukocytes. The present study was designed to investigate the association between TL and serum levels of PCBs and OCPs in Tehran male's population. Whole blood samples were randomly taken from 300 adult males, aged between 25 and 40 years. TL was determined by real-time PCR to measure the number of the telomere (T) repeats to the number of a single-copy gene (S). We applied the multivariate linear regression model to compare the effect of each lipid adjusted serum levels of PCBs and OCPs congener on the TL, with adjustment for age, body mass index, education, smoking, and food patterns. Each doubling of the nondioxin-like PCBs, dioxin-like PCBs, and OCPs levels were associated with 1.9% [95% confidence interval (CI) - 0.70 to 5.40%], 2.5% (95% CI 0.30-8.3%), and - 2.4% (95% CI - 0.70 to - 6.2%) variation in the TL, respectively. The percent difference in the TL with exposure to nondioxin-like PCBs, dioxin-like PCBs, and OCPs for participants with older than age 37 years were 6.45% (95% CI 2.81-16.50%), 4.52% (95% CI 1.60-10.54%), and - 7.44% (95% CI - 1.55 to - 15.51%), respectively. Exposures to nondioxin-like PCBs (except for PCB 28 and 52) with high chlorine in structure and dioxin-like PCBs were related to longer TLs. Conversely, serum levels of OCPs can be associated with oxidative stress and systemic inflammation that lead to telomere shortening.

Association between ambient gaseous and particulate air pollutants and attention deficit hyperactivity disorder (ADHD) in children; a systematic review.

ADHD is a common neurodevelopmental disorder highly attributed to genetics, but the combination of other social and environmental determinants, as well as potential gene-environment interactions, can also be responsible. This paper aims to review relevant literature published up to April 2018 for determining whether air pollution caused by ambient gaseous (NO2, SO2, PCDD/Fs, Benzene) and particulate matters (PM10, PM2.5, PM7, PAH, BC/EC) as an environmental risk factor is associated with increased risk of ADHD in children. Relevant literature was identified through electronic searches of PubMed, Embase, Web of Science, Scopus database and gray literature. A total of 872 articles were initially identified 28 of which meeting the defined inclusion criteria were included. The methodological quality of the included articles was evaluated using the modified Critical Appraisal Skills Programs (CASP) and confounding variables, exposure and outcome measurement were assessed. The results of this systematic review revealed that there is more evidence on the detrimental effects of EC, BC, and PM on ADHD compared to PAH. Among gaseous air pollutants, association was found between SO2 and urinary level of t,t-MA (trans, trans-muconic acid) as a proxy-biomarker of NO2 exposure, not merely benzene. However few studies related to NO2 (0.46%) found detrimental effects. Overall, the number of studies reporting an association between air pollution and increased risk of ADHD is relatively higher compared to the number of studies reporting no association. However, the findings of the studies provided limited evidence to support the idea that exposure to air pollution may be linked to increased risk of ADHD. Well-designed and harmonized studies considering standard methods for individual exposure assessment, critical windows of susceptibility, and appropriate tools for outcome measurement, can improve the quality of epidemiological studies and strengthen the evidence. Since ADHD with its long-term consequences can impose large costs to communities and impact the children performance, determination of the risk factors in children and particularly the role of the environment as priorities for research should be considered.

Prenatal exposure to parabens and anthropometric birth outcomes: A systematic review.

Parabens are ubiquitous substances commonly used as preservatives because of their antibacterial activity. The estrogenic activity of parabens may cause undesirable health effects and adverse birth outcomes. The objective of the present systematic review was to investigate the association between prenatal exposure to parabens and anthropometric birth outcomes. PubMed, Web of Science, Scopus, and Embase databases were systematically searched until April 18, 2018. Of 326 records that remained after removing duplicates, 6 original articles were included in the final analysis after excluding irrelevant articles. The included studies indicated that most of the pregnant mothers were exposed to parabens, especially methyl and propyl parabens. However, no definitive association was found between the prenatal urinary concentration of parabens and birth weight or head circumference. In addition, a positive but non-significant association was detected between birth length and maternal exposure to parabens. The present systematic review revealed that assessment of significant associations in current epidemiological studies is impermissible due to methodological limitations and absence of inter-study consistency. Furthermore, because of the complexity of the effect of environmental factors on health, future large-scale studies with proper study design are required to investigate the effect of parabens exposure on birth outcomes.

Prevalence of diarrheal illness and healthcare-seeking behavior by age-group and sex among the population of Gaza strip: a community-based cross-sectional study.

BACKGROUND: In the Gaza strip, diarrhea is one of main reasons for children visiting primary healthcare centers. Hence, we investigate predictors of the diarrheal illness and health care-seeking behavior among different age groups. METHODS: This community-based cross-sectional survey was conducted from August 2017 to June 2018 among 1857 households. A pretested structured questionnaire included information about socio-demographic, sanitation, hygiene, source of water, diarrheal illness, and seeking healthcare in households was administered to head of household. To achieve representativeness for the five Gaza's governorates, a cluster random sampling was applied. RESULTS: Of the 1857 household's heads, 421 (22.7%) reported an episode of diarrhea during the 48 h preceding the interview resulting an overall prevalence rate of 3.8 per 100 individuals. The prevalence of diarrhea was statistical significant greater in males (5.4/100) compared to females (1.3/100) in all age groups (p <  0.05). Socio-demographic, economic, water, sanitation, and hygiene factors were predictors of the diarrheal illness and seeking of non-professional healthcare for diarrhea illness treatment among. A transition behavior from professional to non-professional and vice versa in seeking healthcare in each diarrheal episode was found. CONCLUSIONS: We recommend improving the status of water, sanitation, and hygiene in the Gaza strip's households to reduce diarrhea among the population of Gaza strip. Community sensitization about the importance of seeking care at primary health centers because treatment of children is available for free or in low costs.

Advantages and disadvantages of different pre-cooking and cooking methods in removal of essential and toxic metals from various rice types- human health risk assessment in Tehran households, Iran.

The aim of present study was to evaluate the effects of different pre-cooking and cooking methods on the concentration of toxic (As, Cd and Pb) and essential (Fe, Cu, Co and Zn) metals in widely consumed rice types by Tehran households, Iran. In this regard, a total of 90 samples were obtained from Iranian, Pakistani and Indian rice brands (30 samples from each brand), and were examined in order to determine the concentration of toxic metals including As, Cd, Pb, Fe, Zn, Co and Cu using ICP-OES. Among these rice brands, the most contaminated one was selected in order to evaluate the effects of washing and soaking processes in different time points (1, 5 and 12 h), as well as different cooking methods (Rinsing and Kateh) in reducing the concentration of subjected metals. Nine samples were analyzed for each process, which were 54 samples in total. Our results show that the preparation and cooking methods applied for all rice brands (except for Indian rice) could effectively reduce the non-carcinogenic risk associated with these metals to the acceptable level; however, this is not true about the carcinogenic risk associated with arsenic. Finally, according to our findings it can be concluded that all cooking methods can lead to considerable removal of rice toxic metals (this is partially true about all available rice brands in Iran), however, a large amount of essential metals were also eliminated by these methods. Moreover, after cooking of different rice types in Iran, this food has still carcinogenic risk associated with arsenic.

A systematic literature review for some toxic metals in widely consumed rice types (domestic and imported) in Iran: Human health risk assessment, uncertainty and sensitivity analysis.

In present study we aimed to investigate the literature in the form of systematic review to determinate the concentrations of some toxic metals (arsenic, lead, and cadmium) in widely consumed rice brands in Iran and their related health risks. International and Iranian national databases were searched carefully with appropriate keywords for papers on toxic metal contamination of rice from Agust-2000 to Agust-2018. Initially, 560 articles were found, of which only the 50 papers fit the inclusion criteria and were selected for further analysis. The Monte Carlo Simulation was applied to generate missing data (mean, standard deviation, data distribution and sample size) of toxic metal concentration in some papers. Then, statistical analysis, health risk assessment, and uncertainty and sensitivity analysis were performed. The results indicated that approximately 88% of rice consumed in Iran (including Iranian, Pakistani and Indian rice) do not meet the national standard and WHO/FAO guideline requirements and their related health risks are unacceptable. The risks of arsenic and lead in Indian rice and cadmium in Iranian rice were considerably higher than others. In conclusion, according to our findings, In conclusion, it is necessary to prevent toxic metals contamination of rice by modifying cultivation patterns and, also, prevent low-quality rice brands to be imported.

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.

Carcinogenic and non-carcinogenic risk assessments of arsenic contamination in drinking water of Ardabil city in the Northwest of Iran.

Based on the environmental health assessment framework of the United State Environmental Protection Agency, a quantitative health risk assessment of arsenic in contaminated drinking water in a city in the northwest of Iran has been carried out. In the exposure assessment step, arsenic concentrations in drinking water were determined during four seasons. In addition, the water ingestion rate for different age groups in this region was determined. The concentration of arsenic in 163 collected samples from different locations during four seasons ranged from 0 to 99 µg L-1. Furthermore, a high percentage of the samples manifested higher levels than the permissible limit of 10 µg L-1. The total daily water intake rates of four age groups 1 to <2 (group 1), 2 to <6 (group 2), 6 to <16 (group 3), and ≥16 years (group 4) were estimated as 0.86, 1.49, 2.00, and 2.33 L day-1, respectively. Calculating the lifetime average daily dose of arsenic indicated that adults (group 4) had the highest and children (group 1) had the lowest daily intake of arsenic in their entire life. The results of risk characteristic showed that the order of excess lifetime cancer risk via arsenic exposure in the four groups was 4 > 3 > 2 > 1. The estimated risks for all age groups were higher than the acceptable range (1E-6 to 1E-4). The hazard quotient values for all of the classified groups were lower than the recommended limit values (<1), but it cannot be concluded that potential non-carcinogenicity risks are non-existent since the possible exposure to arsenic via food and skin may also pose the risk.

Land Use Regression Models for Alkylbenzenes in a Middle Eastern Megacity: Tehran Study of Exposure Prediction for Environmental Health Research (Tehran SEPEHR).

Land use regression (LUR) has not been applied thus far to ambient alkylbenzenes in highly polluted megacities. We advanced LUR models for benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene (BTEX), and total BTEX using measurement based estimates of annual means at 179 sites in Tehran megacity, Iran. Overall, 520 predictors were evaluated, such as The Weather Research and Forecasting Model meteorology predictions, emission inventory, and several new others. The final models with R2 values ranging from 0.64 for p-xylene to 0.70 for benzene were mainly driven by traffic-related variables but the proximity to sewage treatment plants was present in all models indicating a major local source of alkylbenzenes not used in any previous study. We further found that large buffers are needed to explain annual mean concentrations of alkylbenzenes in complex situations of a megacity. About 83% of Tehran's surface had benzene concentrations above air quality standard of 5 µg/m3 set by European Union and Iranian Government. Toluene was the predominant alkylbenzene, and the most polluted area was the city center. Our analyses on differences between wealthier and poorer areas also showed somewhat higher concentrations for the latter. This is the largest LUR study to predict all BTEX species in a megacity.