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Assessment of indoor air quality is especially important, since people spend substantial amounts of time indoors, either at home or at work. This study analyzes concentrations of selected heavy metals in 40 indoor dust samples obtained from houses in the highly-industrialized Asaluyeh city, south Iran in spring and summer seasons (20 samples each). Furthermore, the health risk due to exposure to indoor air pollution is investigated for both children and adults, in a city with several oil refineries and petrochemical industries. The chemical analysis revealed that in both seasons the concentrations of heavy metals followed the order of Cr > Ni > Pb > As > Co > Cd. A significant difference was observed in the concentrations of potential toxic elements (PTEs) such as Cr, As and Ni, since the mean (±stdev) summer levels were at 60.2 ± 9.1 mg kg−1, 5.6 ± 2.7 mg kg−1 and 16.4 ± 1.9 mg kg−1, respectively, while the concentrations were significantly lower in spring (17.6 ± 9.7 mg kg−1, 3.0 ± 1.7 mg kg−1 and 13.5 ± 2.4 mg kg−1 for Cr, As and Ni, respectively). Although the hazard index (HI) values, which denote the possibility of non-carcinogenic risk due to exposure to household heavy metals, were generally low for both children and adults (HI < 1), the carcinogenic risks of arsenic and chromium were found to be above the safe limit of 1 × 10−4 for children through the ingestion pathway, indicating a high cancer risk due to household dust in Asaluyeh, especially in summer.

Cigarette butts are hazardous wastes that are not properly discarded by most smokers. They are one of the most abundant litters in the environment and a threat to various organisms because they leak numerous pollutants. This study aimed to assess the distribution of cigarette butts in a coastal city south of the Caspian Sea in Mazandaran Province, Iran. Observations were performed using the visual survey technique based on standardized protocol. The results showed 11,261 littered cigarette butts in 15 studied urban areas ( an average of 0.306 units per square meter). Also, the average density of littered cigarette butts on the studied beaches was 0.106 per square meter. The littered cigarette butts had significant spatial variation, and the number of counts was 135 to 2090. The land-use has a significant effect on the density of littered cigarette butts due to its population density. The inquiry's index demonstrated that 33.3% of the studied urban areas are high pollution and severe pollution, while all beaches are high and severe. Therefore, a significant focus must be considered to reduce cigarette butts littering due to the collection problems and challenges of cigarette butt management. Because the pollution on the beaches is higher than in urban areas, improving waste management services and establishing a regular cleaning program are essential., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.

Research in urban geochemistry has been expanding globally in recent years, following the trend of the ever-increasing human population living in cities. Environmental problems caused by non-degradable pollutants such as metals and metalloids are of particular interest considering the potential to affect the health of current and future urban residents. In comparison with the extensive global research on urban geochemistry, Iranian cities have not received sufficient study. However, rapid and often uncontrolled urban expansion in Iran over recent years has contributed to an increasing number of studies concerning contamination of urban soil and dust. The present work is based on a comprehensive nationwide evaluation and intercomparison of published quantitative datasets to determine the contamination levels of Iranian cities with respect to potentially toxic elements (PTEs) and assess health risks for urban population. Calculation of geoaccumulation, pollution, and integrated pollution indices facilitated the identification of the elements of most concern in the cities, while both carcinogenic and non-carcinogenic risks have been assessed using a widely accepted health-risk model. The analysis of secondary, literature data revealed a trend of contamination, particularly in old and industrial cities with some alarming levels of health risks. Among the elements of concern, As, Cd, Cu, and Pb were found to be most enriched in soils and dusts of the studied cities based on the calculated geochemical indices. The necessity of designing strategic plans to mitigate possible adverse effects of elevated PTE concentrations in urban environments is emphasized considering the role of long-term exposure in the occurrence of chronic carcinogenic and non-carcinogenic health problems., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Heavy metal pollution significantly reduces the quality of the environment and threatens human health, especially in industrial cities. This study investigated toxic metals concentrations, pollution levels and human health risks assessment of urban soils in Yazd City, as an industrial city in center of Iran. Soil surface samples (0-10 cm) were collected from 30 points in the area for geochemical analysis. The concentrations of heavy metals were determined using an inductively coupled plasma mass spectrometry (ICP-MS). The values of the mean concentrations of toxic metals (mg kg -1 ) in the urban soils decrease in the order of Zn (83.9) > Pb (34.5) > Cr (32.6) > Cu (23.5) > Ni (23.4) > As (5.86) > Co (4.86) > Cd (0.27). The mean concentration of Zn, Pb, As and Cd elements was higher than the background and the crust values. A pollution assessment by Geo-accumulation Index (I geo ), Pollution Index (PI), Contamination Degree (C D ), the Integrated Pollution Index (IPI), the Pollution Load Index (PLI) and Integrated Nemerow Pollution Index (INPI) showed that As, Cd and Pb were moderately enriched and the study area polluted considerably by these toxic metals. Based on PI results, 88.9% of the urban soil samples highly polluted by As. Overall, the quality of the urban soil in Yazd City is clearly affected by toxic metals. Due to the prevailing wind direction, the route of the north-south highway of Iran and the population density and traffic of the northwestern and southern areas of the study area were found the highest level of pollution indicators (IPI > 1.8; LPI > 1.3; C D  > 15 and INPI > 4.3). The results of Pearson correlation analysis indicated that all pollution evaluation indicators were influenced by As and Cu, and showed high significant correlation with these two elements, while neither of them had a significant relationship with Pb and was found also a weak link statistically with Cd. Health risk assessment of toxic metals has been performed in both carcinogenic and non-carcinogenic sectors. The results indicate that oral intake is the main pathway that toxic metals can harm human health for both the child and adults. The carcinogenic risks (RI) of adults and child by toxic metals were as follows: Ni > Pb > Cr > As > Cd. Hazard quotients (HQ) and hazard index (HI) values for child also were higher than these for adults. Generally, the results demonstrated that the potential carcinogenic health risks for adults of toxic metals were in an acceptable range in study area, whereas for Cr, Ni and Pb with RI > 10 -4 , the risk of cancer in child probably increases., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V. part of Springer Nature.)

In this work, a sand and dust storm vulnerability mapping (SDS-VM) approach is developed to model the vulnerability of urban blocks to SDS using GIS spatial analysis and a range of geographical data. The SDS-VM was carried out in Ahvaz, IRAN, representing one of the most dust-polluted cities in West Asia. Here, vulnerability is defined as a function of three components: exposure, sensitivity, and adaptive capacity of the people in the city blocks to sand and dust storms. These components were formulated into measurable indicators (i.e. GIS layers) including: PM 2.5 , wind speed, distance from dust emission sources, demographic statistics (age, gender, family size, education level), number of building floors, building age, land surface temperature (LST), land use, percentage of literate population, distance from health services, distance from city facilities (city center, shopping centers), distance from infrastructure (public transportation, main roads and highways), distance from parks and green spaces, and green area per capita. The components and the indicators were weighted using analytical hierarchy process (AHP). Different levels of risks for the components and the indicators were defined using ordered weighted averaging (OWA). Urban SDS vulnerability maps at different risk levels were generated through spatial multi-criteria data analysis procedure. Vulnerability maps, with different risk levels, were validated against field-collected data of 781 patients hospitalized for dust-related diseases (i.e. respiratory, cardiovascular, and skin). Results showed that (i) SDS vulnerability map, obtained from the developed methodology, gives an overall accuracy of 79%; (ii); regions 1 and 5 of Ahvaz are recognized with the highest and lowest vulnerabilities to SDS, respectively; and (iii) ORness equal to 0 (very low risk) is the optimum SDS-VM risk level for decision-making to mitigate the harmful impacts of SDS in the deposition areas of Ahvaz city., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The COVID-19 pandemic has caused unprecedent negative impacts on our society, however, evidences show a reduction of anthropogenic pressures on the environment. Due to the high importance of environmental conditions on human life quality, it is crucial to model the impact of COVID-19 lockdown on environmental conditions. Consequently, the objective of this study was to model the impact of COVID-19 lockdown on the urban surface ecological status (USES). To this end, the Landsat-8 images of Milan for three pre-lockdown dates (Feb 13, 2018 (MD1), April 18, 2018 (MD2) and Feb 3, 2020 (MD3)) and one date over the lockdown (April 14, 2020 (MD4)), and Wuhan for three pre-lockdown dates (Dec 17, 2017 (WD1), March 23, 2018 (WD2) and Dec 7, 2019 (WD3)) and one lockdown date (Feb 9, 2020 (WD4)) were used. First, pressure-state-response (PSR) framework parameters including index-based built-up index (IBI), vegetation cover (VC), vegetation health index (VHI), land surface temperature (LST) and Wetness were calculated. Second, by combining the PSR framework parameters based on comprehensive ecological evaluation index (CEEI), the USES were modeled on different dates. Thirdly, the USES during the COVID-19 lockdown was compared with the USES for pre-lockdown. The mean (standard deviation) of CEEI for Milan on MD1, MD2, MD3 and MD4 were 0.52 (0.12), 0.60 (0.19), 0.57 (0.13) and 0.45 (0.16), respectively. Also, these values for Wuhan on WD1, WD2, WD3 and WD4 were 0.63 (0.14), 0.67 (0.15), 0.60 (0.13) and 0.57 (0.13), respectively. Due to the lockdowns, the mean CEEI of built-up, bare soil and green spaces for Milan and Wuhan decreased by [0.18, 0.02, 0.08], [0.13, 0.06, 0.05], respectively. During the lockdown period, the USES improved substantially due to the reduction of anthropogenic activities in the urban environment., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

It is imperative to comprehend the level and spatial distribution of soil pollution with heavy metals to find sustainable management approaches for affected soils. Selected heavy metals (Mn, Zn, Pb, Cu, Cr, Ni, As, Co, and Cd) and physiochemical parameters were appraised for 620 samples from industrial, agricultural and urban sites in Northern Ireland using the Tellus database. The findings of this study showed that among the analyzed heavy metals, Mn content was the highest and Cd content the lowest. Pearson's correlation analysis revealed that heavy metals were highly correlated with each other, signifying similar sources for the heavy metals. Mixed factors (anthropogenic and lithogenic) were responsible for the contribution of heavy metals as revealed by multivariate statistical analysis. The results of contamination factor and enrichment factor analyses suggest that As, Cd, and Pb showed very high risk for pollution in the study area. The geoaccumulation index revealed that with the exception of Cd, all analyzed heavy metals showed severe accumulation in the soils. The potential and modified ecological risk indices inferred that Cd, As, and Pb represented ecological threats in the soils of Northern Ireland. The findings of this study will aid in forming approaches to decrease the risks associated with heavy metals in industrial, urban and agricultural soils, and help create guidelines to protect the environment from long-term accumulation of heavy metals.

This literature review was conducted to collect present data on microplastics pollution in Iran's ecosystems. Most of the studies performed in aquatic environment were conducted in Persian Gulf & Oman Sea (70%). The Persian Gulf, along with the beaches of Bushehr and Hormozgan Provinces, are the most studied areas. Moreover, most of the studies were conducted in aquatic environments and only four studies were conducted in terrestrial environment (4/42). One study has assessed microplastics in commercial salt and another study has reported the microplastics presence in Iranian bottled mineral water brands. The investigation of microplastics associated with biota was highlighted, customarily for fish species. Microplastics were also present in urban wastewater samples in Sari and Bandar Abbas cities. Three studies were performed in freshwater ecosystems until now (Haraz River, Anzali wetland, and Taleqan dam). The need for further studies in this field still exists, especially in terrestrial and freshwater compartments., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The levels of Cd, Cr, Cu, Fe, Mn, Pb and Zn were determined in floor dusts from mechanical (MRWs) and battery repairing workshops (BRWs) in Yazd, Iran. The study aimed to evaluate the anthropogenic contribution to the presence of heavy metals (HMs), the possible sources and the related risks that could arise from occupational exposure in the studied workplace microenvironments. Among the analyzed heavy metals, Cu, Pb and Zn exhibited enhanced concentrations in the floor dusts. The EF calculations showed an extremely severe enrichment of HMs, especially for Cd, Cu and Pb, while floor dusts were characterized as "extremely polluted" with regards to those metals. In any case, both EF and I geo values were significantly higher in the BRWs. These results were also supported by NIPI and PLI values, while contour maps of PLI values in both MRWs and BRWs outlined workshops in N-NE part of Yazd as more impacted compared to other spatial locations. Principal component analysis (PCA) and Pearson's correlation outscored workshops activities as the principal sources of heavy metals. The health risk assessment suggested considerable non-carcinogenic risks regarding Pb in the BRWs which exhibited HQ ing (mean 2.91) and HI (mean 3.03) values higher than safe level. Regarding carcinogenic risks, CR values for both Cd and Cr were below the safe level (1.0 × 10 -6 ). The occupational exposure to Pb was evaluated through the predicted BLL values, where with averages of 3.33 μg/dl and 21.4 μg/dl for MRWs and BRWs workers, respectively, indicated a severe Pb exposure for BRWs workers., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Wind is one of the main factors affecting people's outdoor thermal sensation. Ongoing urbanization and urban densification are transforming the urban climate and complicating the pedestrian-level wind environment. Therefore, the main aim of this research is to evaluate the potential wind-cooling effect on human outdoor thermal conditions. Accordingly, the current research attempts determine the best wind directions for thermal comfort at the studied stations and how these factors will be changed under the effects of global warming. Outdoor thermal conditions were modeled based on the physiologically equivalent temperature (PET) thermal index using RayMan software for the decades of the 2000s and the 2040s in different climate types of Iran (Csb, BWh, Csa, and BSh) To estimate the potential cooling effect of wind, the PET was calculated (1) under actual wind conditions, and (2) under calm wind (0.05 m/s) conditions. Then, the ΔPET for these two conditions, which indicates the cooling potential effect (CPE) of the wind, was calculated for four representative stations (Ardebil, Bandar Abbas, Gorgan, and Shiraz). In comparison with the 2000s, the results indicated that by the 2040s, the predicted wind cooling potential will have increased in Ardebil, Shiraz, Bandar Abbas and Gorgan (CPE of 13.2 °C, 13.1 °C, 11.2 °C, and 11 °C, respectively). Based on the overall average of two climate change scenarios (A2 and B1) used in this study, the occurrence of "comfortable" conditions by the 2040s will have increased in Bandar Abbas, Shiraz, and Ardebil by 1.1%, 0.4%, and 0.3%, respectively, while it will have decreased in Gorgan by 1.5%. Accounting for the cooling effect of wind, the comfort cooling potential of wind is predicted to rise by an average of 1.6 °C in the 2040s compared with the 2000s in all the studied stations. Therefore, this will affect the microclimates positively and could reduce the urban heat island effects., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This paper aimed to explore knowledge, attitudes, and practices (KAP) of women towards the municipal solid waste (MSW) management in Tehran, Iran, to provide a basis for experts and decision-makers to develop or improve practical waste management strategies. Women's contribution could markedly promote accomplishment of MSW management strategies, which has been neglected in many developing countries. A cross-sectional study was conducted in two stages: first, a random sample of 384 respondent women was selected from the 22 urban districts of Tehran, then 64 of them were randomly selected and trained face-to-face. The second phase was aimed at determining the effectiveness of face-to-face training and its impact on women's performance in waste management. In both stages, data were collected using a structured self-administered questionnaire containing 21 questions in four categories. Chi square (χ 2 ) and Pearson correlation tests were applied to identify the association among variables. Results indicated that 69.6% and 72.9% of the women had adequate knowledge and attitude, respectively, while only 46.0% performed moderate practice on MSW management. Overall, significant association between education level, occupation, and marital status of the women with KAP towards reduction, reuse, recycling, and recovery of MSW were yielded (p < 0.05). Adequate knowledge and positive attitude did not necessarily lead to the proper practice in this study. However, face-to-face training positively affected women's practice in solid waste recycling and source separation. Conducting training programs and motivation of women by municipalities and decision-makers to elevate women's environmental performance could substantially promote MSW management strategies in developing nations.

Transformational management properties could make the weakest organizations strong with the right and efficient approach build. The aim of this study was to determine the transformational management properties among hospital managers in Gonbad-e-Kavus. In terms of data collection, the present study is an an applied research involving objective and descriptive-analytical surveys. The statistical population includes all staff hospitals that were selected randomly in Gonbad-e-Kavous city. The present study was performed including 7 hospitals and 346 respondents. Castiglion transformational management properties questionnaire (2006) was used to collect the required data, with Cronbach's alpha coefficient (0.946). Based on the findings of the research, 67.3% (233 subjects) of the participants in the study evaluated the transformational management properties of the managers of the hospitals at a good level (with a score of 140. 76 ± 27.76), with Payambar Hospital having the highest (151.57 ± 20.31) and Taleghani Hospital the lowest score (130.22 ± 28.10) attributed to the management properties affecting change management. Based on the findings of the research and the impact of effective transformational management properties among the managers of the understudy hospitals, it is recommended to form all effective management transformational management properties, through founding special educational units and holding classes for hospital managers, in order to form various skills and competencies such as communication skills, skills to influence others, trusting, attention skills, and providing sufficient independence which all play an essential role in the success of managers and pave the ground for the flourishment of transformation and innovation in the hospitals., (©Carol Davila University Press.)

Green space and its spatial formation are important elements of public welfare in urban environments and green ecosystems in big cities largely contribute to the mental and physical health of citizens. Tehran is Iran's biggest and most polluted city and air pollution in this city causes loss of human lives due to respiratory diseases. The effect of green area has been less studied in former researches in Tehran, and the reducing effects of green landscape on the mortality of respiratory diseases have not yet been evaluated. To measure the effects of green area landscape patterns (fragmentation, area-edge, shape, and aggregation) on public health, the current study evaluated the pathways and effects of green space on air pollution and the mortality of respiratory diseases using structural equation modeling approach and the partial least squares method. The results of the study indicated green space has a significant mitigating effect on air pollution and mortality of respiratory diseases and also air pollution has a meaningful increasing effect on mortality due to respiratory diseases in Tehran. The most important latent variable in green space is class area that indicates more area of green space is correlated with less mortality of respiratory diseases. The most important indicator of air pollution was the PM 2.5 that needs to be considered and controlled by urban policymakers. Accordingly, maximizing the green area and its cohesion and minimizing fragmentation and green patch edge can contribute to a reduction in air pollution and consequently lower mortality of citizens.

Background: Cardiovascular disease (CVD) is the leading cause of death in the world. With effective intervention and control of cardiovascular risk factors, mortality rates may be reduced. The aim of this study was to investigate the prevalence of modifiable risk factors across five municipalities in Yazd city., Methods: Ten thousand residents of the Yazd greater area aged 20-69 years were selected using cluster random sampling method. Overall, 200 clusters were randomly selected based on the postcodes of residents who lived in the five municipalities of Yazd. Those who lived in Yazd annexed cities and rural areas were excluded. A valid questionnaire was completed and physical examination performed as done (94.9% response rate). Instances of self-reported diabetes mellitus, high blood cholesterol, tobacco smoking, and unhealthy diet were recorded. Blood pressure, height, and weight were measured and physical activity was classified by International Physical Activity Questionnaire (IPAQ). A chi-square test was used to analyze the differences in variables across municipalities. Statistical analyses were performed using SPSS V. 16., Results: We analyzed 8749 participants' data from Yazd city. The prevalence of diabetes mellitus, hypercholesterolemia, and hypertension were 14.1, 16.7 and 18.6%, respectively. One in every four people consumed the recommended five servings of vegetables per day. Fish consumption was less than 5% at least once a week among participants. An unhealthy diet (85.7%); low physical activity (52.2%), hypertension (36.7%) and obesity (26.3%) were the most common cardiovascular risk factors. Only 2.1% of adults had no risk factors for CVD, and almost 75% of people had more than one risk factor. The prevalence of risk factors (excluding hypertension) was significantly different across the municipalities. Residents of region three had the highest prevalence of all risk factors aside from inactivity and unhealthy diet., Conclusion: unhealthy dietary habits and inactivity are the most common modifiable risk factors of CVD in Yazd. Spatial variations of cardiovascular risk factors observed. This geographic health inequality requires more attention from policymakers to control CVD risk factors across different municipalities accordingly. Promoting healthy lifestyle is the top priority of health intervention programs. It is recommended to increase access to sport arenas and restrict access to tobacconist in high-risk areas.

Due to population growth and the considerable increase in usage of the resources, Human environment quality has been highly threatened by pollutants in recent decades. Polycyclic aromatic hydrocarbons (PAHs) are widespread, persistent organic pollutants which are of great concern due to their carcinogenicity. The present study is the first investigation that assesses contamination, sources and cancer risk of 16 priority PAHs proposed by US EPA in urban dust samples (n = 80) taken in different land-uses of Tehran metropolis, the capital of Iran. Gas chromatography-mass spectrometry (GC-MS) is used to measure PAHs concentrations. The results showed that the average concentration of the total 16 PAHs and the average Benzo[a]pyrene total potency equivalency were 566 μg kg -1 dry weight and 36.4 μg kg -1 , respectively. In the commercial and residential land-uses high molecular weight (HMW) PAHs were dominated, whereas in green lands, light molecular weight (LMW) PAHs showed maximum contribution. The highest concentration of total PAHs were observed in the commercial areas due to limited air circulation and heavy traffic loads. Incremental Lifetime Cancer Risk (ILCR) model was applied to evaluate the cancer risk of exposure to PAHs contaminated dust. Based on the results, Tehran's residents (children and adults) in various land-uses except for green lands, are in high potential cancer risk of PAHs via ingestion and dermal contact exposure routs. Ace, Chr, Pyr, and BghiP which are indicators of traffic emissions, were found to be predominant PAH contributors in urban dust of commercial areas. Also, Ace, Fl, Phe, and BghiP which are derived from fossil fuel combustion, were mainly observed in the industrial land-use. Based on the results of factor analysis and diagnostic ratios, Diesel/gasoline engine vehicular emissions and combustion were found to be the main sources of PAHs in urban dust of Tehran., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Increased atmospheric particulate matter (PM) concentrations are commonly observed during desert dust days in Iran, but there is still no evidence of their effects on human health. We aimed to evaluate the association between daily mortality and exposure to PM 10 and PM 2.5 during dust and non-dust days in Tehran and Ahvaz, two major Middle Eastern cities with different sources, intensity, and frequency of desert dust days., Methods: We identified desert dust days based on exceeding a daily PM 10 concentration threshold of 150 µg/m 3 between 2014 and 2017, checking for low PM 2.5 /PM 10 ratio typical of dust days. We used a time-stratified case-crossover design to estimate the short-term effects of PM 10 and PM 2.5 concentrations on daily mortality during dust and non-dust days. Data was analyzed using conditional Poisson regression models., Results: Higher concentrations of PM and frequency of desert dust days were observed in Ahvaz rather than Tehran. In Ahvaz, the effect of PM 10 at lag 0 was much higher during dust days, an increment of 10 μg/m 3 was associated with 3.28% (95%CI = [2.42, 4.15]) increase of daily mortality, than non-dust days, 1.03% (95%CI = [-0.02, 2.08]), while in Tehran, was slightly higher during non-dust days, 0.72% (95%CI = [0.23, 1.23]), than in dust days, 0.49% (95%CI = [-0.22, 1.20]). No statistically significant associations were observed between PM 2.5 and daily mortality in Ahvaz, while in Teheran the effect of PM 2.5 increased significantly during non-dust days at lag 2, 1.89% (95%CI = [0.83, 1.2.95] and lag 3, 1.88% (95%CI = [0.83, 1.2.95])., Conclusion: The study provides evidence that exposure to PM during Middle East dust days is an important risk factor to human health in arid regions and areas affected by desert dust events., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Maximizing resource recovery from waste streams (e.g., energy) is a critical challenge for municipalities. Utilizing the ultimate analysis and high heat value (HHV), we investigated the energy recovery and emission characteristics for 252 solid wastes of a diverse range of geographical origins classifications (e.g., 30 paper, 12 textile, 12 rubber and leather, 29 MSW mixture, 34 plastic, 61 wood, 20 sewage sludge and 53 other wastes) under the thermal waste-to-energy operation. Given the significance of wastes' HHV data, we proposed a rapid and cost-effective methodology for filling the gaps in the experimental data by prediction of the missing or uncertain wastes' HHV. We further employed wastes' nitrogen and sulphur contents to assess their atmospheric emissions. The results from this analysis show the highest energy content belonged to plastic waste, but higher levels of air pollution (mainly due to nitrogen and sulfur) could be emitted during thermal energy recovery of sewage sludge, rubber, and textile wastes. Also, we demonstrated more significant potential for recovering energy from plastic, wood, and paper wastes, while emitting less nitrogen and sulphur compounds to the atmosphere. Finally, our presented HHV models outperform concerning generalizability, validity, and accuracy when comparing the obtained results to those of previously published models. The results from this present study are particularly advantageous in designing sustainable thermal waste-to-energy systems to facilitate cities' transition into a circular economy., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

By growing urban population, Iran faces numerous environmental issues and solid waste management is on the top of these problems. Studies showed that a daily average of 700-1000 g of wastes are produced per person in Iran, in which organic waste accounts for a significant amount. On the other hand, hospital waste represents a part of the wastes, which need careful consideration from the environmental point of view. In the present study, the amount, composition, and management of urban and hospital wastes were evaluated in 7 Iranian metropolises, which account for about 30% of the population and produce about 35% of the country wastes. Based on prior surveys, landfill method is the current main method for waste management in these cities, which is generally not completely sanitary and therefore causes many environmental problems. The other common methods for waste management in these cities are composting of organic wastes, and the use of waste conversion methods to energy. However, the latter is ongoing only in Tehran which also includes some limitations. Therefore, the study also evaluated the future perspectives and feasibility of waste-to-energy conversion as a promising economic route for waste disposal.

Low impact development (LID) methods have been shown to be efficient in reducing the peak flow and total volume of urban stormwater, which is a top priority for effective urban stormwater management in many municipalities. However, decision-makers need information on the effects of LIDs and their associated costs before allocating limited resources. In this study, the Storm Water Management Model (SWMM) was used to investigate the effects of five different LID scenarios on urban flooding in a district in Tehran, Iran. The LID scenarios included rain barrel (RB) at two sizes, bio-retention cell (BRC), and combinations of the two structures. The results showed that significant node flooding and overflow volume would occur in the study area under the existing conditions, especially for rainfall events with longer return periods. BRC and combinations of BRC and RBs were the most effective options in reducing flooding, while the smaller-size RB was the cheapest alternative. However, normalized cost, obtained through dividing the total cost by the percent reduction in node flooding and/or overflow volume, was smallest for BRC. The results of this study demonstrate how hydraulic modeling can be combined with economic analysis to identify the most efficient and affordable LID practices for urban areas.

Regulating ecosystem services provided by urban forests are of great importance for the quality of life among city dwellers. To reach a maximum contribution to well-being in cities, the urban regulating ecosystem services (URES) must match with the demands in terms of space and time. If we understand the matches or mismatches between the current urban dwellers' desired quality conditions (demand) and the supply of URES by urban forests (UF) in the cities, this will facilitate integrating the concepts of ecosystem services in urban planning and management, but such an assessment has suffered from major knowledge limitations. Since it is complex and problematic to identify the direct demands for URES and the spatiotemporal patterns therein, improving the demand indicators can help to determine the actual requirements. In this paper, a methodological approach based on indicators is presented and demonstrated for two important URES: air quality improvement and global climate change mitigation provided by urban trees and shrubs. Four air quality standards and greenhouse gas reduction targets were used and compared to supplies of the URES in Tabriz, Iran. Our results show that the mean contribution of the URES supply to air quality standards and greenhouse gas reduction targets is modest. Hence, in Tabriz, there is a strong mismatch between demand and supply. Mismatches at the city scale will have to be reduced by both a reduction in pollutant emissions and an increased provisioning of URES supply through urban greenery. The presented assessment approach and the results for Tabriz make it explicit how different the demands and supplies of the two studied URES are, and we expect similar mismatches in many other cities. Therefore, our approach, relatively simple but still realistic and easy-to-apply, can raise awareness about, and the utility of, the ecosystem services concepts for urban planning and policymaking., Competing Interests: The authors have declared that no competing interests exist.

The PM 2.5 as one of the main pollutants in Tehran city has a devastating effect on human health. Knowing the key parameters associated with PM 2.5 concentration is essential to take effective actions to reduce the concentration of these particles. This study assesses the relationship between meteorological (humidity, pressure, temperature, precipitation, and wind speed) and environmental parameters (normalize difference vegetation index and land surface temperature of MODIS satellite data) on PM 2.5 concentration in Tehran city. The Geographically Weighted Regression (GWR) was employed to assess the impact of key parameters on PM 2.5 concentrations in winter and summer. For this purpose, first the seasonal average of meteorological data were extracted and synchronized to satellite data. Then, using the ordinary least square model, the important parameters related to PM 2.5 concentration were determined and evaluated. Finally, using the GWR model, the relationships between parameters related to PM 2.5 concentration were analyzed. The results of this study indicate that meteorological and environmental parameters in winter season (71%) have a much higher ability to explain PM 2.5 concentration than summer season (40%). In winter, PM 2.5 concentration has a negative correlation with vegetation at most parts of the study area, a negative correlation with LST in the western and a positive correlation in the eastern part of the study area, a positive correlation with temperature, and a negative correlation with wind speed in the northeastern part of the study area. Precipitation has a positive correlation with PM 2.5 concentration in most parts of the study area in both seasons. But, it was investigated in case of higher precipitation (more than 2 mm), PM 2.5 concentration decreases. But, there is no negative relationship in any of the dependent parameters with PM 2.5 concentration in summer. In this season, the air temperature parameter showed a high correlation with PM 2.5 concentration. Also, spatial variations of the local coefficients for all parameters are higher in winter than in summer.

Air pollution is a major concern in some megacities of Iran. Specific cities in the country have reached an extremely harmful level of air pollution which poses a serious risk to the daily lives of Iranians. According to news reports, the air quality index of the city of Tehran hovers around 159, which is more than three times the World Health Organization's advised maximum. For the purpose of air pollution abatement, it is necessary to precisely know the air pollution distribution in the area. In order to obtain this figure, it is necessary to properly locate the city's air quality monitoring stations that measure the spatial pollutant distribution. According to various reports, the city must have at least 56 air quality monitoring stations to properly measure Tehran's air quality. However, there are currently only 20 stations within the city. Thus, the main purpose of this study was to identify the most sufficient areas for deploying new air quality monitoring stations. This study provided an integration of hybrid multi-criteria decision-making (MCDM) theories and geographical information system (GIS) processes in order to determine suitable areas to establish air quality monitoring stations. Unlike traditional models, the proposed MCDM method, ANP-OWA, is an efficient decision analysis which considers dependencies between criteria and defines different scenarios between pessimistic and optimistic conditions for decision makers. This method was applied to several parameters such as point, area, and line sources; population density; sensitive receptors; distance from current air quality stations; prediction error; and spatial distribution of CO, NO 2 , SO 2 , and PM 10 pollutants. The output results specified several suitable locations to establish air pollution monitoring stations within Tehran Province. The stability and reliability of the output results were evaluated with a robust sensitivity analysis method. Moreover, the results demonstrated that the proposed method can produce stable results. Obtaining knowledge regarding population density, distance from current air quality stations, and spatial distribution of CO pollutant criteria is essential when selecting locations for air quality monitoring stations.

This study aims to study the waste management process and recycling of municipal waste in Tehran. Currently, Kahrizak is the defined landfill area which collects the waste generated from 22 districts of Tehran. The organic wastes undergo to the windrow composting method in order to manage the partial of the waste generated in the city. Samples from the compost pile generated in Kahrizak were examined to evaluate its fertilizer value to be used further by the farmers. The results show that the obtained compost does not reach the acceptable quality to be used further in agriculture, due to lack of homogeneity, aeration and presence of heavy metals. Overall, it has been concluded that, due to the improper waste segregation and management prior to sending to landfill and presence of non-organic materials such as hazardous metals and medical wastes, causes difficulties in proper waste management, implementation and producing high quality compost. Based on this study the existence of stakeholders, society, economy and proper handling rules can effectively improve the waste management system in the country and leads to the sustainable green environment.

Soils play a vital role in the quality of the urban environment and the health of its residents. City soils and street dusts accumulate various contaminants and particularly potentially toxic elements (PTEs) from a variety of human activities. This study investigates the current condition of elemental concentration in the urban soils of Hamedan, the largest and the fastest-growing city in western Iran. Thirty-four composite soil samples were collected from 0 to 10 cm topsoil of various land uses in Hamedan city and were analyzed for total concentration of 63 elements by ICP-MS. The possible sources of elemental loadings were verified using multivariate statistical methods (principal component analysis and cluster analysis) and geochemical indices. The spatial variability of the main PTEs was mapped using geographic information system (GIS) technique. The results revealed a concentration for As, Co, Cr, Mn, Mo, Ni, and V in the soil samples comparable to the background values as well as a range of associations among these elements in a single component suggesting geogenic sources related to geological and pedogenic processes, while the soils mostly presented a moderate to considerable enrichment/contamination of Cd, Zn, Pb, and Sb and moderate enrichment/contamination of Cu, Zn, and Mo. It was found that anthropogenic factors, vehicular traffic in particular, control the concentration of a spectrum of elements that are typical of human activities, i.e., Cd, Cu, Hg, Pb, Sb, and Zn. Lead and Sb were both the most enriched elements in soils with no correlation with land use highlighting general urban emissions over time and the impact of transport networks directly on soil quality. The highest concentrations of As were recorded in the southern part of the city reflecting the influence of metamorphic rocks. The effect of the geological substrate on the Co and Ni contents was confirmed by their maximum concentrations in the city's marginal areas. However, high spatial variability of urban elements' contents displayed the contribution of various human activities. In particular, the increased concentration of Cd, Sb, and Pb was found to be consistent with the areas where vehicular traffic is heaviest.

Wastewater disinfection processes are typically designed according to heuristics derived from batch experiments in which the interaction among wastewater quality, reactor hydraulics, and inactivation kinetics is often neglected. In this paper, a computational fluid dynamics (CFD) study was conducted in a nondeterministic (ND) modeling framework to predict the Escherichia coli inactivation by peracetic acid (PAA) in municipal contact tanks fed by secondary settled wastewater effluent. The extent and variability associated with the observed inactivation kinetics were both satisfactorily predicted by the stochastic inactivation model at a 95% confidence level. Moreover, it was found that (a) the process variability induced by reactor hydraulics is negligible when compared to the one caused by inactivation kinetics, (b) the PAA dose required for meeting regulations is dictated equally by the fixed limit of the microbial concentration as well as its probability of occurrence, and (c) neglecting the probability of occurrence during process sizing could lead to an underestimation of the PAA dose required by as much as 100%. Finally, the ND-CFD model was used to generate sizing information in the form of probabilistic disinfection curves relating E. coli inactivation and probability of occurrence with the average PAA dose and PAA residual concentration at the outlet of the contact tank.

This articles presents the status of municipal solid waste (MSW) management practices in the city of Isfahan, Iran. It provides an overview of the generation, collection, separation, recycling and disposal of MSW. Field studies were carried out from 2009 to 2010. According to this study, the city generates about 399,000 metric tons of MSW per year, of which 72.5% is organic matter. In Isfahan more than 90% of the MSW is collected by official municipal forces and the other 10% is collected by informal collectors. About 70% of the MSW in Isfahan is composted to produce a humus material, 5% is rejected and 25% is stockpiled for future use as fuel in a waste-to-energy incineration plant. Non-compostable waste and other residues are landfilled. This investigation also includes an analysis of economic benefits that could be realized by implementing incineration and a discussion of the challenges confronted in Isfahan for implementing changes to the city's existing MSW management system. This article concludes with recommendations for improving the city's MSW management system.