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Lime is a significant material in many industrial processes, including steelmaking by blast furnace. Lime production through rotary kilns is a standard method in industries, yet it has depreciation, high energy consumption, and environmental pollution. A model of the lime production process can help to not only increase our knowledge and awareness but also can help reduce its disadvantages. This paper presents a black-box model by Artificial Neural Network (ANN) for the lime production process considering pre-heater, rotary kiln, and cooler parameters. To this end, actual data are collected from Zobahan Isfahan Steel Company, Iran, which consists of 746 data obtained in a duration of one year. The proposed model considers 23 input variables, predicting the amount of produced lime as an output variable. The ANN parameters such as number of hidden layers, number of neurons in each layer, activation functions, and training algorithm are optimized. Then, the sensitivity of the optimum model to the input variables is investigated. Top-three input variables are selected on the basis of one-group sensitivity analysis and their interactions are studied. Finally, an ANN model is developed considering the top-three most effective input variables. The mean square error of the proposed models with 23 and 3 inputs are equal to 0.000693 and 0.004061, respectively, which shows a high prediction capability of the two proposed models. [ABSTRACT FROM AUTHOR]

Nowadays, the amounts of infectious medical waste (IMW) have surged considerably so waste management has become a critical emergency in many developing countries. However, most large medical waste generation centers (MWGC) are equipped with treatment facilities, small MWGC faces the waste management problem. It reveals the significance of having a proper program for small health centers. This is an indisputable difficulty that governments bordered because it imposes great costs on societies, also the environmental problems caused by improper treatment are irreparable. To attend to all the essential aspects of the problem, this paper recommended a location-routing model with four objective functions to minimize the total costs, environmental pollution, the risk imposed on the population around disposal sites, and the total violation from the expected arrival time. Considering a multi-period problem with a maximum acceptable delay plays a key role to connect the assumptions to the real-world problem. In addition, for solving mathematical models based on case studies, the role of uncertainty is undeniable. The demand for dental waste treatment is not definite and is changed based on the different conditions thus fuzzy chance-constrained programming is proposed for this problem to tackle the uncertainty. The revised multi-choice goal programming method is considered to solve the model and a real case study for dental clinics in Babol city of Iran is investigated to illustrate the validation of the proposed model. The results indicate that the solution method can create a balance between four objective functions. Finally, sensitivity analyses are performed for some parameters to analyze the behavior of the objective functions. [ABSTRACT FROM AUTHOR]

Implementation of projects with an acceptable quality level in the minimum cost and time has always been the ultimate goal of managers and decision-makers in the construction industry. On the other hand, the construction industry is responsible for creating various environmental problems. Therefore, reducing the environmental destructive effects of project implementation is of utmost importance. The aim of this paper is to consider the environmental pollution along with the project iron triangle of cost, time, and quality in the scheduling of the construction projects. A multi-objective multi-mode resource-constraint project scheduling model is presented considering the generalized precedence constraints between project activities as well as the limitation of renewable resources and non-renewable resources. In this study, the environmental effects of construction projects as well as the three conflicting goals of cost (budget), time (duration), and quality are taken into account. Also, the limitations of renewable and non-renewable resources as well as the generalized activity precedence relationships are incorporated into the proposed model. The proposed model was implemented on a rural water supply project including 25 activities and was solved using the fuzzy goal programming approach with GAMS software. Different combinations of activity modes were presented along with the start time of each activity considering four objective functions. The results showed that this project would be completed in 190 days, at the cost of $15,394, with the quality level of 0.835, and environmental effects of 0.372, which are between the optimal and worst objective functions values. In addition, the sensitivity analysis indicates the high efficiency of the proposed model and its capability in assisting project managers and planners. [ABSTRACT FROM AUTHOR]

The relationship between the environment and green projects has become an important issue since the 1970s. This issue is of particular importance for Iran, which seeks to solve the problem of environmental pollution caused by the consumption of fossil fuels and also seeks to increase the participation of green energy in the economy through the development of green projects. This study aims to investigate the environmental impact of the Kahak wind farm project in the Qazvin province of Iran. In this regard, the opinions of 10 green project experts and the Riam matrix method were used as a flexible and acceptable method in calculating the environmental impact of economic projects in this paper. The results revealed that this wind farm project positively impacts air quality and climate, social welfare, and hydraulic resource. At the same time, patrimony, fauna, and vegetation are affected negatively by this project. As the practical policy implications, the paper recommends strategies to increase private sector participation, combined location of green projects based on feasibility and environmental impacts, and establishment of Regional Green Development Projects (RGDP). [ABSTRACT FROM AUTHOR]

Efficient investigation of sediment core samples is crucial for understanding the extent and sources of pollution in aquatic ecosystems. Accordingly, Anzali Wetland, located southwest of the Caspian Sea, is one of the most important and unique ecosystems in Iran. This paper evaluated the accumulation of metals, agricultural pesticides, and petroleum hydrocarbons in the core sample of sediment in the central area of Anzali Wetland. For this purpose, 180 cm core sediment was extracted. Then, accurate concentrations of metals, agricultural pesticides, and petroleum hydrocarbons were determined utilizing two general digestion and four-step chemical separation method, Gas Chromatography and Spectrofluorophotometer. Using cluster analysis, obtained data were analyzed and then discussed according to the standard indices, including the enrichment factor (EF), geoaccumulation index (Igeo), pollution load index (PLI), index of pollution (Ipoll), and Risk Assessment (RI). The results indicated that the sediment of this wetland has low to moderate pollution. However, the amounts of cadmium and mercury as toxic metals were high in some parts of the sediment, indicating that the impact of anthropogenic pollution was significant. The sedimentation rate was 6.7 mm per year, and Darzban (chlorpyrifos) was more than other agricultural toxins. Moreover, oil pollution was not detected in Central Anzali Wetland, while hydrocarbon pollution caused by vascular plants and the entry of vegetable oils into municipal wastewater was detected. The highest agricultural pesticide was 74 mg/kg. Besides, 14% increase was observed in the amount of organic matter which was attributed to the inflow of wastewater and the growth of Azolla. [ABSTRACT FROM AUTHOR]

The present paper addresses a novel two-echelon multi-product Location-Allocation-Routing problem (LARP). It also considers the integration of issues such as disruption, environmental pollution, and energy-efficient vehicles as currently critical issues in a Supply Chain Network (SCN) that includes production plants, central warehouses, and retailers. The aim of this study is to minimize the total cost, which involves costs related to the establishment, shipment processes, environmental pollution, travelling, vehicle usage, and fuel consumption, in a way to cover the total demand of retailers. The problem is NP-hard; thus, to solve it approximately, we developed Grey Wolf Optimization (GWO) and Particle Swarm Optimization (PSO) algorithms. The numerical analysis showed that the proposed algorithms yielded high-quality results in a short computational time where the average gaps of GWO and PSO against CPLEX are 0.78% and 0.9%, respectively. Then, a case study of a dairy factory in Iran is conducted to evaluate the applicability of the proposed methodology and find the optimal policy. Finally, a set of sensitivity analyses is carried out to suggest managerial insights and decision aids. [ABSTRACT FROM AUTHOR]

The development of agricultural, industrial, and urban activities creates an increase in pollution loading in rivers that may violate water quality standards which in its turn results in damages to the river systems. An efficient model of waste-load allocation plays a significant role in improving the water quality of the rivers. In this paper, a cost-based waste-load allocation model (C-WLA) is applied to guarantee the optimal management of both costs and river water quality. To determine the optimal loading pattern and threshold limits, the trade-off between treatment cost and pollution loss from the river is considered. In this regard, the MIKE11 model is coupled with the Particle Swarm Optimization (PSO) algorithm and applied to the Karoon River in Iran to demonstrate its practicality and efficiency. The sum of water treatment cost and pollution loading loss is minimized and the monthly optimal treatment percentages and threshold limit were determined. Then, different strategies under various operations of the river system are given with insights into the impacts of the trade-off policy between costs and losses for the discharger's TDS removal. The results demonstrated that the C-WLA model can achieve optimal management of pollution load in various operating of the river system. In addition, it is also shown that the proposed method is expected to offer better decision support to reasonable waste-load allocation where it can encourage dischargers to improve loading performance. [ABSTRACT FROM AUTHOR]

In recent decades, the risks and environmental damage caused by economic growth, population growth and energy consumption have become more apparent. Meanwhile, one of the new advances in the study of the relationship between economic factors affecting environmental quality is the attention to the spatial nature of environmental phenomena. Therefore, the aim of this study was to model the relationship between carbon dioxide (CO2) emissions and economic growth along with other influential factors. CO2 emissions as a criterion for environmental pollution in Iran have been studied using the Spatial Durbin Model (SDM) and in the framework of spatial panel data among the provinces of Iran during the period 2003-2017. The results of this study show that in total, real GDP per capita increases CO2 emissions at the provincial level, because the positive real GDP per capita coefficient is larger than the negative real GDP per capita coefficient of space. Another very important variable in increasing CO2 emissions in the provinces is the intensity of energy consumption and its spatial interruption, which has the highest significant and positive coefficients in the model of this paper. Also, the weighted price of provincial energy and its space interruption have had a significant and negative effect on CO2 emissions. Although increasing the degree of urbanization has not had a significant effect on CO2 emissions in the same province, but increasing the degree of urbanization in neighboring provinces has increased CO2 emissions. Finally, the spatial interruption coefficient of the dependent variable is significant and positive, which shows that the increase in CO2 emissions in neighboring provinces has increased CO2 emissions in the same province. [ABSTRACT FROM AUTHOR]

Owing to the rise in population, lifestyle changes, high traffic rates in urban areas and environmental pollution, respiratory diseases have become much more prevalent on both regional and urban scales. Respiratory diseases affect over 300 million people worldwide and are thus among the major threats to humans' general well-being. The identification of underlying factors and the specification of accompanying risk areas for the temporal exacerbation of respiratory diseases are effective steps in managing the damage caused by such disorders. Here, we demonstrate a strategy for modelling the risk zone of respiratory diseases temporally, using a location-based social network (LBSN) and an artificial neural network (ANN). The main contribution of this paper is to consider the environmental and infrastructural factors and identify their relationships with the geographical locations of respiratory attacks. The study also utilizes Telegram, which is the most popular and conventional social media platform, in order to observe temporal changes in the location of respiratory attacks in Iran, in the form of a developed Telegram bot known as @respiratoryassociation. The relations between the factors behind and the location of respiratory attacks are determined using a multilayer perceptron (MLP) ANN. All the required data have been collected on a daily basis over a 5-year period from December 2013 to December 2018 in Tehran, Iran. The results indicated air pollution, especially pollution from carbon monoxide (CO) and suspended particulate matter (PM) as the most decisive factors. Following air pollution, the amount of exposure to the polluted area was determined as the second most decisive factor, which in turn increased as a result of escalations in traffic jams. Land use was determined as the third most decisive factor. Furthermore, the results revealed that the ANN performed satisfactorily, implying that the model can be used to examine the spatio-temporal behaviour of the time series of respiratory diseases with respect to environmental and infrastructural factors. [ABSTRACT FROM AUTHOR]

This paper aimed to identify and evaluate the environmental factors that influence human health in Hashtpar. The town locates in the coastal plain of northern Iran and has an area of 1378 ha and a population of about 53,000 people. Fourteen indicators were included in the dataset and the data was collected in 34 data collection points through the evaluation of at least 5 experienced people or by calculations using Geographical Information System (GIS) and related shape files. First, it is used a descriptive and qualitative method and statistical parameters to analyze each determinant of health, regardless of its spatial differences, then the data entered into GIS to produce zoning maps using the Kriging interpolation tool. Findings show that generally, healthy environment indicators are higher than average level and the indicators are in better condition in central parts of the town than in its outskirts. [ABSTRACT FROM AUTHOR]

For over a decade now, decomposition analysis has become popular in energy and environment studies. This paper therefore identifies the factors that have influenced changes in CO2 emissions in Iran for the period 1990-2010. The Refined Laspeyres Index method has been utilized in order to decompose the CO2 emissions while four main factors of the observed changes have been identified: economic activity, energy intensity (energy use per unit of economic output), carbon intensity (CO2 emission per unit of energy use), and population effect. The study period has been divided into two decades, the first one encompassing the period from 1990 to 2000 and the second one from 2000 to 2010. Our empirical findings have revealed that the main factor which is accelerating CO2 emissions in Iran is the economic activity for the entire study period. Also within the first decade of the study, economic activity has been followed by energy intensity while in the second decade; it has been followed by population effect. Furthermore, the carbon intensity has made minor contributions to CO2 emissions in Iran throughout the study period. Given that Iran is an energy intensive and largely oil dependent country; we therefore suggest it would be better off in terms of reduced CO2 emissions by pushing down current energy intensity as its main environmental and economic policy objective. For the future studies, a sectoral CO2 emissions analysis could be conducted for Iran in order to examine the carbon emissions increasing and decreasing factors and provide some sectoral policy implications. [ABSTRACT FROM AUTHOR]

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Emission utilization permission is an interesting but complex issue regarding the environmental effect of pollution. This paper proposes a mathematical programming–based approach to emission utilization permission taking environmental efficiency into consideration. We use this approach for an environmental efficiency analysis and emission utilization permission (extra emission permission) of selected economic sectors in Iran, namely, agriculture, oil, industry, transportation, and domestic, commercial, and public. We use a gradually decreasing scheme for the process of emission utilization permission to investigate the condition of each sector during the process. The result reveals a vital need of improvement for two sectors, namely, oil sector and transportation sector, at the end of emission utilization permission process that is very tight in terms of emission permission. [ABSTRACT FROM AUTHOR]

Living organisms are affected by environmental pollution, one main source of which is the electric and magnetic fields (EMFs) of electrical distribution lines that produce high-voltage currents. Nowadays, electrical power transmission lines and distribution systems are becoming increasingly prevalent, with power distribution lines passing through cities and being located very close to buildings. For this reason, there has been significant public concern, which has escalated because of reports about the adverse health effects of the EMFs of power distribution systems. In this paper, the environmental pollution produced by several different configurations of electrical distribution systems in Iran is studied. The paper presents new software to calculate EMFs around electric power lines. Using this software and based on maximum allowable EMFs, a safe margin around selected power lines has been determined. According to the study results, it seems that in Iran this safe distance is not met. Therefore, the standards relating to power distribution lines should be reviewed. [ABSTRACT FROM AUTHOR]

Since the production and consumption of meat are known to be among the leading causes of greenhouse gas emissions and environmental pollution, this study examines the relationship between the consumption of various types of red meat by households and its impact on air pollution and environmental contamination in Iran. For this purpose, this article tests this relationship using annual time series data from 1980 to 2019 and the FMOLS method. The findings indicate that the consumption of red meat has a negative effect on environmental pollution because it leads to air pollution and increases environmental pollution. According to the results, the consumption of cow and veal meat has a greater contribution on air pollution and environmental pollution, and the consumption of camel meat has the lowest contribution. Furthermore, the growth of consumption, which leads to the development of production in the economy, can result in air and environmental pollution, as meat production is an energy and input-intensive process. In light of these findings, policymakers must focus on controlling household consumption and production of these products by implementing tax and incentive policies to decrease environmental pollution. [ABSTRACT FROM AUTHOR]

Background: Ecological conditions can change infection routes and increase the risks of outbreaks. The aim of this study is risk assessment of foodborne disease outbreaks based on dispersed regional climatic and demographic variables in Yazd Province, Iran. Methods: In this cross-sectional study, data of temporal climatic parameters and regional demographic factors linked to bacterial foodborne diseases were addressed. A multi-level regression analysis model was used to detect associations between the risk of outbreaks and ecological risk factors; the relationships were verified using (P<0.05). Results: Significant associations were observed between the outbreaks and age)P<0.001(, community type (P<0.001), temperature (P=0.04), rainfall (P=0.03) and dust pollution (P<0.001) in scattered parts of the province. The maximum rate of outbreaks was seen in spring, while the frequency of the outbreaks increased during April and October, compared to other months of the year (2012-2016). Conclusion: Consequences have revealed interventions of the environmental exposures in transmissions of microbial agents by complex ecological processes that caused the outbreaks. [ABSTRACT FROM AUTHOR]

Energy is one of the most important influential factors on economic growth. In recent decades, upward trend of energy consumption has caused many concerns about decrease in energy source and increase in pollution and global warming. Iran as one of the greatest oil and natural gas exporters with high consumption of gas, oil and electricity faces with pollution problems in cities and hence the necessity of a plan to decrease the energy consumption. In this paper, we study demand of energy consumption and predict consumption of diverse kinds of energy during 2010-2018. In this regard, by adopting Bayesian approach and with concern to data of 1970-2009, we forecast the trends of energy consumption. The result showed that during recent years, up to the average growth rate of energy consumption is equal to 1.8 per cent. The slower growth of energy consumption leads to a slower economic growth and in turn, causes a decline in energy consumption due to the structural changes in the Iran economy. [ABSTRACT FROM AUTHOR]

Mining is widely regarded as having adverse effects on environment of both magnitude and diversity. Some of these effects include erosion, formation of sinkhole, biodiversity loss and contamination of groundwater by chemical from the mining process in general and open-pit mining in particular. As such, a repeatable process to evaluate these effects primarily aims to diminish them. This paper applies Folchi method to evaluate the impact of open-pit mining in four Iranian mines that lacked previous geo-environmental assessment. Having key geologic resources, these mines are: Mouteh gold mine, Gol-e-Gohar and Chogart iron mines, and Sarcheshmeh copper mine. The environmental components can be defined as public health and safety, social relationships, air and water quality, flora and fauna hence, various impacting factors from the mining activities were estimated for each environmental component. For this purpose, each impacting factor was first given a magnitude, based solely on the range of possible scenarios. Thereafter, a matrix of weighted factors was derived to systematically quantify and normalize the effects of each impacting factor. The overall impact upon each individual environmental component was then calculated by summing the weighted rates. Here, Folchi method was applied to evaluate those environmental conditions. Based on the acquired results, the present paper finally concludes that amongst four case histories in Iran, Sarcheshmeh copper mine significantly affects the environment, with critical level of air pollution there. [ABSTRACT FROM AUTHOR]

Having heavy impacts on human's life, pollution adversely influences life. In this paper, a comprehensive model of the Arak's air pollution for different pollutant chemicals NOx, CO, and SO2 is developed. Here, all effective fixed and mobile sources of pollution are within 50 km distance of the city. The topology of ground surface and also climate patterns of different local areas were carefully considered to accurately model the distribution of pollution. Then, comparing the results with data taken from the ambient air monitoring, the model was validated. According to our findings maximum of NOx concentration in Arak city, Iran was 7.7 times of standard value. This figure is 2.2 and 17.5 times for CO and SO2 pollutants. Share of industry, for spring season, is 51%, 86% and 100% for NOx, CO, and SO2, respectively. Moreover, IRALCO itself has 31% share in total NOx pollution, while its share for CO and SO2 pollution dramatically increases to 85% and 100%, respectively. [ABSTRACT FROM AUTHOR]

Purpose: The present study aims at quantifying the likely impacts of an environmental tax on macroeconomic variables and pollution in Iran. Design/methodology/approach: The computable general equilibrium model, which allows the prediction of the economy-wide effects of any change in policy instruments, is applied. Findings: The main findings reveal that gross domestic product, private consumption and income in both urban and rural areas will follow a declining trend as a result of environmental tax imposition. In a scenario with the highest level of tax, the predicted percentage change to the gross domestic product and private consumption is estimated at −21.32 and −40.96, respectively. In the same scenario, pollution emissions would decrease by 12.4–22.6% for CO2, CH4 and N2O. Originality/value: This study uses a general equilibrium model to examine the effects of the carbon tax on environmental issues and household welfare, considering the unique conditions and regulations of Iran. While the related literature examines the CO2 tax, the current study covers more pollutants, including CO2, CH4, N2O, CO, SO2 and NOx. In addition, a distinguishing feature of the current study is that it applies a modified version of the social accounting matrix (SAM) database, which includes the heavy subsidies of energy products. Another significant feature of the current study is that it examines tax policy while tax rates are exerted endogenously (compared to previous studies). [ABSTRACT FROM AUTHOR]

The assessment of heavy metal(oid) concentrations in agricultural soil holds significant importance due to its impact on crop safety and quality, as well as the potential risks it poses to human health. This review utilized secondary online published data to evaluate the contamination levels of seven HMs (As, Cd, Cu, Cr, Ni, Pb, and Zn) in Iranian farmland soils. As a result, 31 research papers were collected to compile a dataset offering a comprehensive analysis of HM concentrations, distribution, sources, ecological risks, and potential health risks. The findings indicated that mean concentrations of Ni and Cd exceeded their corresponding permissible levels in farmland soils, while other HMs remained below this threshold. The mean Igeo (geoaccumulation index) values followed the sequence Ni > As > Cu > Cr > Zn > Pb > Cd, with Igeo values suggesting low to slight enrichment for the studied HMs. Pollution index (PI) results revealed notable contamination of As in various provinces, including Kurdistan, Hamedan, Tehran, Mazandaran, West Azerbaijan, Kermanshah, Hormozgan, Golestan, and the Kamfiruz region of Fars. Elevated contamination of Pb and Cd was observed in Fars (Shiraz region), and Cr and Ni in the Sabzevar area farmland soils. As, Cd, and Cu exhibited higher ecological risks (EI) compared to Zn, Cr, Ni, and Pb. The potential ecological risks (PER) ranged from 9.9 to 244.6, indicating low to moderate risk levels. Non-carcinogenic assessments indicated that ingestion was the primary exposure pathway to HMs in Iranian farmland soils, followed by inhalation and dermal contact. Total hazard index (HI) values for studied HMs did not exceed 1, indicating no significant non-carcinogenic risk for both population age groups. This study highlights the current lack of well-documented scientific reports on the status of HMs in agricultural farmland soils across 12 other provinces in Iran, emphasizing the need for further investigation. Moreover, the bioavailability of HMs in agricultural soils significantly influences HM content in crops, underscoring the need for future research to ascertain HM concentrations in different soil fractions. • Agricultural practices and geology are the main sources of HMs. • Pollution index of HMs falls in the category of serious to low contamination. • Children are more prone to being affected by HMs in Iran farmland soils. • As and Cr showed the most contribution to the no-carcinogenic and carcinogenic risks. [ABSTRACT FROM AUTHOR]

Environmental pollution is a serious threat to the sustainable development of Middle East countries, especially Iran. Therefore, in this article was analyzed the decoupling relationship between CO2 emissions energy-related and economic growth in 6 Middle East countries in period 1990-2019. First, CO2 emissions driving mechanisms were quantified using Logarithmic Mean Divisia Index (LMDI) method, and then decomposed into factors of CO2 emission coefficient, energy intensity, economic activity and population. The decoupling state findings using the Tapio model show that population and economic activities factors were main drivers of CO2 emissions in these countries. The results of decoupling elasticity showed that Iran was in a weak decoupling state in period of 1990-1999 and 2015-2019; It means the simultaneous increase of economic growth and carbon emissions, of course, by faster economic growth; Iran had also an expansive coupling state in period of 2000-2014, which indicates that CO2 emissions increase along economic growth. The UAE and Saudi Arabia have reached an ideal situation in recent years. These countries have moved from a negative decoupling and expansive coupling state to a strong decoupling state, where economic growth has been accompanied by a reduction in carbon emissions. The Kuwait and Turkey have been in weak decoupling and negative expansive decoupling states in the last 3 decades, in which economic growth was accompanied by an increase in carbon emissions. At the beginning, the Egypt has changed to a weak decoupling state and then moved to an expansive negative decoupling state. [ABSTRACT FROM AUTHOR]

Abstract: As global energy demand rises, natural gas (NG) plays a pivotal role in energy supply. Natural gas is the cleanest fossil fuel and it has high energy conversion efficiencies for power generation. Natural gas has been extensively investigated for use in spark-ignition (SI) and compression-ignition (CI) engines. This paper consists of two sections: the first section gives an overview of natural gas fuel in the world and highlights the share of natural gas in Iran energy market and then expounds the role of natural gas vehicles (NGVs) in the context of Iran environmental pollution and its sustainable development. It is concluded that natural gas is the promising alternative fuel for vehicles in Iran. In the second part, the paper reviews the research works on natural gas fueled engines by Iranian researchers, and reports the most achievements obtained by them in the field of the natural gas fueled engines which involve natural gas-fueled SI engines, dual fuel (natural gas/diesel) engines, and Homogenous Charge Combustion Ignition (HCCI) engines. It is found that Iranian researchers started investigations on NGVs along with world researchers and developed research in line with their needs and priorities. Recently they further focused on this topic and their contribution to this field is significant especially regarding dual fuel engines. [Copyright &y& Elsevier]

This paper investigates the impacts of urban growth on groundwater quality and quantity in the Zahedan aquifer, which is the sole source of water supply for the city of Zahedan, Iran. The investigation is based on the collection of available historical data, supplemented by field and laboratory investigations. Groundwater levels in 40 wells were measured in December 2000. In addition, 102 water samples were taken in two periods during November and December 2000. Of these, 43 samples were analyzed for major ions, 32 samples were analyzed for nitrogen and phosphorus and the remainder for bacteriological contamination. The water level data show that there has been a general decline since 1977 due to over-abstraction. The magnitude of this decline has reached about 20 m in some places. However, in one area over the same period, a rise of about 3 m has been observed. This occurs as a result of the local hydrogeological conditions of shallow bedrock and relatively low permeability materials down stream of this area that limits the flow of groundwater towards the northeastern part of the aquifer. The general fall in groundwater levels has been accompanied by a change in the direction of the groundwater flow and an overall reduction of the areal extent of the saturated region of the aquifer. The city now has a serious problem such that even if the abstracted groundwater is rationed, water is not available for long periods because the demand far exceeds the supply. The heavy impact of urbanization on the groundwater quality is shown through the observed high nitrate (up to 295 mg/l as nitrate) and high phosphorus values (about 0.1 mg/l as P). Significant changes in the chloride concentration are also observed in two areas: increasing from 100 mg/l to 1,600 mg/l and from 2,000 mg/l to 4, 000 mg/l, respectively. Furthermore, the bacteriological investigations show that 33 percent of the 27 collected groundwater samples are positive for total coliform and 11 percent of the samples contained fecal coliforms indicating that local sources are strongly influencing the observed chemical data. Greater depths to groundwater reduce the observation of coliform contamination. In general, the unplanned urban development in Zahedan has significantly degraded the region's water resources and significant actions such as upgrading the sewage waste disposal system, locating other sources of water supply, and strict groundwater management will all be needed to resolve the problems that have arisen. [ABSTRACT FROM AUTHOR]

There is a growing concern about the pollution of agricultural systems caused by plastic residue and debris. This pollution poses a threat to the quality of food products. To gain a deeper understanding of how to maintain cleaner farmlands and reduce plastic residue and debris pollution, this cross-sectional study investigated the intention and behavior of plastic residue management (BPRM) in farmlands. Using random sampling method, the study surveyed 338 farmers in northwestern Iran. The resulting evidence found that 37.6% of farmers perform the BPRM with a mean score above average. The path analysis cleared that among the conceptualized ecological, economic, and social connotations, only the ecological attitude had a significant and positive impact on the BPRM (β E c o A t t i → B H V = 0.28, p < 0.001). It was found that both fact feedback (β F F B s → Int = 0.76, p < 0.001) and causal feedback (β C F B s → Int = 0.22, p < 0.001) contribute to reducing plastic residue pollution and forecasting the intention to perform the BPRM. The intention, in turn, directly predicts BPRM (β Int → B H V = 0.30, p < 0.001). Using a 2 × 2 cross-tabulation of causal feedback and the scenario of landfilling, derived from perceived action-based life cycle analysis of plastic wastes, the association between the two variables was found to be statistically significant (x 2 (df) = 3.24(1), p < 0.05). The resulting evidence would provide essential information for farm management strategists and governmental authorities to reduce plastic residue pollution in farmlands. This can be achieved by implementing policy initiatives that aim to change farmers' intentions and behaviors. • Paper indicates how to keep farmlands cleaner from plastic residue pollution. • Factual feedback forecasts intention to perform plastic residue management behavior. • Cause feedback predicts intention to perform plastic residue management behavior. • Cause feedback links with scenario of landfilling from action-based life cycle. • Factual and causal feedback should be given to farmers. [ABSTRACT FROM AUTHOR]

The current study aims to evaluate the health risk of heavy metals for humans and animals in the Angouran mining complex (northwest of Iran). Twenty-five plant species and their corresponding soils (natural soils) were collected along with mine tailings samples. The carcinogenic and non-carcinogenic risks of heavy metals (Zn, Pb, Cd, Cr, and Co) for humans using the hazard quotient (HQ) and hazard index (HI) were evaluated. Moreover, the health risk caused by forage feeding to grazing ruminants (cow and sheep) and the risk associated with animal products consumption by humans in the soil-plant-animal transfer system were assessed. The value of HI in natural soils (rangeland use) was less than one (HI < 1), while regarding tailings, the HQ via oral ingestion and the HI were greater than one (HI & HQ > 1). The range of total carcinogenesis risk in natural soils exceeded the target risk (Risk < 10-6) and for tailings, it showed the probability of cancer risk, 1 person per 3636 populations, which is much higher than the acceptable or tolerable range (10-4 < Risk < 10-6). Regarding the animal health risk, the content of Pb and Cd in most of the animal organs was higher than the control values. In turn, dietary exposure to Pb and Cd is worrying for residents due to exceeding the provisional tolerable weekly intake (PTWI). This comprehensive study suggests the necessity of risk assessment of mining sites in Iran and immediate control measures to diminish pollutants. [ABSTRACT FROM AUTHOR]

Background: The present research addressed the spatiotemporal variations in such pollutants as benzene, toluene, ethylbenzene, and xylene (BTEX) in the atmosphere of Arak, a city in central Iran. Also, the health risk evaluation and ozone formation potential (OFP) were assessed. Methods: The air samples were collected and evaluated through gas chromatography-mass spectrometry (GC-MS) over a one-year period. Results: The overall BTEX levels ranged between 2.7-256 μgr/m³. The seasonal levels showed considerable variations among benzene, toluene, ethylbenzene, and xylene, and the levels of total BTEX. Comparison of the air samples between morning and evening for the concentrations of BTEX components revealed that the values were higher in the evening; however, there were no significant differences observed among them. The spatial map indicated that the maximal concentration of BTEX components occurred in high-traffic zones of the city. The maximal and minimal OFP levels were recorded in the summer (2 54.8 μgr/m³) and autumn (64.9 μgr/m³), respectively. The average toluene/benzene (T/B) ratio found to be 4.3, indicating the fuel combustion was the major source of atmospheric BTEX from vehicles. Conclusion: The measured cancer risk value for benzene (6.68×10-5) was higher than those recommended by the WHO and U.S. Environmental Protection Agency. Therefore, exposure to atmospheric benzene had a carcinogenic risk for Arak inhabitants. This needs further investigation in future studies. The acceptable hazard quotients (<1) for all BTEX species posed minimal risks of non-cancer diseases for the population. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is one of the main global pollutants that may biomagnify in food nets, especially in wetlands. Birds may be useful in the biomonitoring of Hg in such habitats and may even serve in vivo samples. This paper examined Hg concentration in the feathers of seven bird species foraging on Fereydunkenar International wetland (in 2013). Mean Hg concentrations found ranged from 0.005 ± 0.002 μg g−1 d.w. (dry weight) (Common hoopoe) to 0.38 ± 0.047 μg g−1 d.w. (Greylag goose). Significant differences in Hg concentrations were noted between bird species as well as between trophic levels (one-way ANOVAs, p < 0.001). The decrease in mean Hg concentration in feathers was as follows: Greylag goose > Northern pintail ≥ Gadwall ≥ Mallard > Eurasian bittern ≥ Little bittern > Common hoopoe. The position in the trophic chain significantly influenced Hg concentrations, which were the highest in omnivorous species. Hg concentrations may also depend on migration routes and breeding habitats, but the evaluation of the exposure exceeds the ambit of this paper. The Hg concentrations found generally were low, lower than the safe thresholds reported in the literature. [ABSTRACT FROM AUTHOR]

The aim of this research was to use a variety of leaching methods to see how different parameters affected the amount of lead leaching from tailings. Synthetic precipitation leaching procedure, toxicity characteristic leaching procedure, leachate extraction procedure, and field leach test protocols were utilized to assess the toxicity of the tailings. The impact of the liquid-solid ratio, particle size, contact time, and pH on lead release from tailings was also investigated. According to the findings, pH entirely effects on the release of lead from the tailings, and amphoteric leaching behavior was observed. The tailings were classified as hazardous material as a result of the TCLP leaching protocol's findings. S1 and S2 samples had lead mobility indexes of 51% and 5.6%, respectively. The solubility process influenced the discharge of lead from the tailings. In the particle size ranges of 0.3-0.5 mm and 0.6-1.0 mm, respectively, the maximum amount of lead was released from S1 and S2 samples. Various experiments have shown that the interaction between different factors will have complex and strong effects on the leaching process. To that end, managing of tailings and preventing lead emission into the environment necessitates a unique technique. Leachability is affected by a number of factors and often multiple factors can produce synergistically different releases than would be predicted by each factor alone. However, validation of the leaching approaches to field-collected and monitored cases indicates that combined effects are either captured by the test data or can be considered through fate and transport modeling. [ABSTRACT FROM AUTHOR]

Mojen Plain is an important agricultural and horticultural region in northeastern Iran. The main objective of this study was to evaluate the advert impacts of agricultural practices on the soil and groundwater resources of the Mojen Plain. The results of the study revealed that Cd, As, Cu, Zn, Ni, Cr, and Mn accumulations (with average concentrations of 0.6, 9.3. 16.4, 61.9, 22.1, 25.5, and 305.4, respectively) in the soils are due to agricultural practices which may result in the non-carcinogenic risk of As, Mn, and Cr through ingestion and dermal contact. In the groundwater of the study area, the average hazard quotient of As, Cd, Cr, Ni, Mo, Pb, and Cu through dermal contact route is higher than 1, indicating the probable non-carcinogenic risks of these elements. The average incremental lifetime cancer risk (ILCR) of dissolved As, Cd, and Pb through dermal contact exposure route was found to be higher than 1 × 10−4, implying a carcinogenic risk of these elements in the study area. While the water quality for irrigation purposes ranges from excellent to permissible, As and Cr content of water samples exceeds the WHO standards for drinking water. Nickel, Fe, Al, Pb, Zn, Cu, and Cd concentration in groundwater samples falls within the acceptable range of the WHO standard. Except for Ni and Co, a negative correlation exists between the concentration of toxic elements and the tube well depths, pointing to the anthropogenic origin of the toxic elements. The concentration of nitrate and phosphate, as the two major agricultural pollutants of groundwater, is generally higher in tube wells deeper than 175 m, reaffirming the impact of agricultural practice on groundwater quality. [ABSTRACT FROM AUTHOR]

The ever-increasing global demand for energy, oil production/supply and the necessity for alternative approaches regarding energy harvesting have opened a deeper horizon for natural gas utilization. The complexity of the demand–supply match of natural gas and the lack of an optimal pattern of energy consumption have been daunting tasks for the energy decision-makers in the last century. Although laws regarding energy efficiency are formulated and even implemented in some cases, there was no benchmarking analysis which takes all useful indexes into account until recently. However, in this article, by identifying the factors affecting the pattern of gas consumption through the system dynamic approach, regulations associated with productivity are assessed. For this, a regional dynamic integrated gas model is developed. The model effectiveness in handling the system dynamism and various scenarios are investigated through a real case study in Yazd—a central province of Iran—to ascertain the proposed approach. The results show that the developed targeted subsidy law is effective in the household sector. Despite the fact that the thorough implementation of the energy efficiency regulations has positive environmental and economic impacts, these regulations have not been fully implemented in many cases and do not have the required efficiency in the industry sector. [ABSTRACT FROM AUTHOR]

In the present study, lead, zinc and copper concentrations in the feathers of Common kestrel (Falco tinnunculus), Eurasian magpie (Pica pica), Common buzzard (Buteo buteo), Crested lark (Galerida cristata), Eurasian hoopoe (Upupa epops), Little owl (Athene noctua), Long-eared owl (Asio otus), Eurasian eagle-owl (Bubo bubo) and Long-legged buzzard (Buteo rufinus) from Sabzevar and Neghab, Khorasan Razavi of Iran were measured. Almost all of the specimens were obtained from birds that had collided with vehicles or were unable to fly. There were no significant differences in metal concentrations between adult and juvenile, diurnal and nocturnal raptors and species with different diets. Elemental concentrations were lower than toxicity threshold values, so exposure to these elements does not appear to pose a health risk to the studied species. It should be noted that this study was the first study of metals in Galerida cristata, Asio otus and Buteo rufinus. [ABSTRACT FROM AUTHOR]

Iran's agricultural production has expanded significantly in recent years. Environmental pollution caused by the use of energy and chemical fertilizers, depletion of groundwater resources, and soil erosion, on the other hand, demonstrates a lack of attention to the environmental dimension of production in this country. In addition to these issues, climate change has exacerbated the agriculture sector's difficulties. This study intends to investigate the asymmetric relationship between energy consumption, chemical fertilizer consumption, CO2 emissions, temperature changes, and production from 1961 to 2019 using the NARDL approach and Granger causality test in the frequency domain (Breitung and Candelon.). Short-term and long-term estimates revealed that the positive and negative shock effects of energy consumption on production are both positive. As a result, it was observed that the negative shock of increased energy consumption had a greater influence on agricultural output than the positive shock. In the long run, the positive shock of fertilizer use has a positive effect on and improves production. But the effect of a negative shock is insignificant. Furthermore, the negative shock of CO2 emission has a positive effect on production. Finally, positive and negative shocks in temperature changes were discovered to have an increasing and reducing influence on production. The results of the Granger causality test in the frequency domain test showed that there is a bidirectional causality relationship between energy consumption and agro-production in the long term. There is also unidirectional causality from CO2 emissions and fertilizer consumption to production and from production to climate change. According to the findings, reforming energy prices, investing in mechanized agriculture, shifting away from fossil fuel consumption towards renewable energy, and tending to green growth are all necessary to achieve multiple goals such as optimizing energy consumption, reducing environmental pollution, and improving efficiency. [ABSTRACT FROM AUTHOR]

Potentially toxic elements (PTEs) constitute a class of metals, semimetals, and non-metals that are of concern due to their persistence, toxicity, bioaccumulation, and biomagnification in high concentrations, posing risks to the ecosystem and to human health. A systematic literature review (SLR) was used in this study to identify natural and anthropogenic sources of PTEs for the aquatic environment. The databases consulted were ScienceDirect, Scopus, and Web of Science, in the period 2000–2020, using specific terms and filters. After analyzing the titles, abstracts, and full texts, 79 articles were selected for the SLR, in which 15 sources and 16 PTEs were identified. The main anthropogenic sources identified were mining, agriculture, industries, and domestic effluents, and the main natural sources identified were weathering of rocks and geogenic origin. Some places where environmental remediation studies can be carried out were highlighted such as Guangdong province, in China, presenting values of Cd, Cr, and Cu exceeding the national legislation from drinking water and soil quality, and Ardabil Province, in Iran, presenting values of As, Cr, Cu, Ni, Zn, and Pb exceeding the standard for freshwater sediments of USEPA, among others places. With the results exposed in this work, the government and the competent bodies of each locality will be able to develop strategies and public policies aimed at the main sources and places of contamination, in order to prevent and remedy the pollution of aquatic environments by potentially toxic elements. [ABSTRACT FROM AUTHOR]

To reduce environmental pollution, it is essential to use green processes in dyeing and meet its requirements. Most natural dyes have a low affinity to be used in the dyeing process. To refine this limitation, the mordanting flow is necessary for many dyeing cases. Pumpkin extract as a natural, metal-rich source can be used as a bio-mordant in green dyeing of natural yarns such as wool. Two natural dyes native to Iran, Reseda luteola and madder, were employed in this study. The effectiveness of bio-mordant presence on yarns was evaluated by FTIR-ATR test from mordanted and mordanted-dyed wool samples. The study of K/S (color strength) content of dyed samples showed that increasing the dye concentration increases the amount of K/S. Fastness performance of wool dyed with pumpkin alternated from good to excellent depending on natural dye type and concentration, due to the formation of complex structures. [ABSTRACT FROM AUTHOR]

The environment is one of the main concerns in global policies and affects many other factors including the economy. Trade liberalization would affect environmental quality through its effect on production. This study aims to express the effect of the trade liberalization policy on environmental pollution in the frame of a multi-regional system model. Thus, the GTAP-E model was utilized for the year 2019, so that the environmental consequences (in terms of measurement of CO2 emission) could be studied as the result of reducing the tariffs on import in the forms of two scenarios. In the first scenario, the import tariff on agricultural, industry and services products was reduced by 5%, and in the second scenario, the import tariff on the agricultural, industry and services sectors was reduced by 5%, 10% and 15%, respectively. The results obtained in both cases indicate a reduction in the effect of scale, technique and composition. The results indicate that an import tariff reduction in the various sectors of the economy reduces pollution emissions and its effects improve the environment. The second scenario has a greater effect on the different sectors and also is closer to the reality of Iran’s economy. [ABSTRACT FROM AUTHOR]

Background: Today, the environmental crisis of pollution of water resources with municipal and industrial wastewater containing microplastic (MP) pollutants has become a global problem. Likewise, in Ardabil Province, Iran, municipal wastewater is discharged into the water of the River Qarasu and is the primary source of the MP pollution crisis. Materials and Methods: In this descriptive cross-sectional study, the samples were taken from 5 stations in the Qarasu (Karkarq, Sarband, Anzab Sofla, Dolatabad, and Samian villages) under standard methods in 2020. The sample analysis and MP separation method were performed based on the density difference and digestion methodology. It was completed using stereo microscopy with a digital camera, fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Results: Studies show that WWTPs (Wastewater Treatment Plants) are the primary sources of releasing MPs into the environment. In addition to threats to water resources, MPs are consumed and digested by aquatic organisms. As a result, MPs can affect human health, the environment, and the river's living organisms. Conclusion: The study results showed that MPs had been introduced into the River Qarasu ecosystem. MPs can have dangerous effects on the environment and living organisms and lead to an environmental crisis of water resources. Therefore, continuous river pollution monitoring is vital in the environmental crisis. [ABSTRACT FROM AUTHOR]

A systematic approach was used on monthly data from three hydrometric stations located on the Gheshlagh River (west of Iran) to investigate the flow–concentration relationship and for river base flow analysis. According to the results of this study, the water quality of the Gheshlagh River has been affected by changes in river flow as well as human activities. Using the analysis of flow–concentration relationships obtained for Khalife Tarkhan station, the higher concentration of dissolved solids in groundwater (with a base flow rate from 0.1 to 0.7 m3/s) rather than surface runoff was estimated. Also, in this station, with the increase of river flow and improvement of river self-purification capacity, water quality parameters showed a decreasing trend compared to the groundwater. In Hossein Abad's upstream station, due to low average river flow and discharge of saline drainage from agricultural lands, an increasing trend in the dissolved solids both for groundwater and surface runoff was shown. The trend of spatial changes in river water quality also indicates the high impact of human activities such as fish farms and wastewater discharge of Sanandaj wastewater treatment plant, on increasing the concentration of dissolved solids in Dareh Kolleh downstream station. [ABSTRACT FROM AUTHOR]

Large amounts of environmental pollutants that occur in nature mean a serious problem. Improving productivity as one of the most important sources of economic growth means using efficient production for all resources including labor, capital and energy. The main purpose of this study is to investigate the relationship between energy efficiency and CO2 and SO2 emissions as a criterion for environmental pollution and consumption of energy carriers and to determine the most effective factor on energy efficiency in Iran's agricultural sector. In this study, to achieve the objectives of the research, annual data on the consumption of energy carriers and environmental pollutants during the period 1988–2016 for the agricultural sector of Iran using Eviews10 software and vector regression model have been used. The results show that the decrease in energy efficiency in the agricultural sector by 1.037 and the increase in energy consumption by 1771.2 and with one difference, The energy efficiency of the agricultural sector has increased by 0.53 which indicates the optimal and efficient use of energy. Labor has been positive with two interruptions, and capital is positive in the first interruption, which is the most important factor influencing the energy efficiency of the agricultural sector and shows an increase in energy efficiency of the agricultural sector. The highest CO2 emissions are related to electricity prices. Given the positive relationship between electricity prices and emissions, it can be said that the increase in electricity prices in the agricultural sector (26,714.39) should be partially replaced by fossil fuels, thus increasing pollution and reducing energy efficiency. [ABSTRACT FROM AUTHOR]

Applying the principles of healthy products through agriculture practices has become an important issue due to significant environmental impacts of agrochemicals application. The agrochemicals have been recognized as an essential component of modern agriculture, but they are also an important source of environmental pollution that threatens the human's health and are main sources of carbon emissions. Pesticides and fertilizers application are important in the process of Iran's food production. In Iran, intensifying the agricultural production has led to overuse of chemical fertilizers and pesticides. This work is the first effort to quantify and compare the decoupling index pollution from agricultural sector using Tapio decoupling indicator and predict climate change impacts on this index by using Bayesian network across the whole country of Iran. For this purpose, required annual data of predictor variables for the period of 2008 to 2018 was used to calculate the decoupling index. For projecting climate change impacts on this index by using Bayesian network, monthly mean values of climatic variables were used. While Iranian farmers are criticized for pesticide overuse, these study findings showed that during the period of 2008–2018, decoupling index for pesticides (agricultural pollution by using pesticide) and decoupling index for fertilizer (agricultural pollution by using fertilizer) in the selected provinces fluctuate between RD-SD, SD-SD, SD-SD, and RD-SD. Therefore, the decoupling states show that in most study years, there is a strong decoupling of agricultural growth in selected provinces. This means that in the selected provinces, pollutant emissions of chemical fertilizer and pesticides use for agricultural productions have decreased and it has been well controlled. Therefore, by expansion of agricultural sector, the situation of agricultural pollution in these provinces in most years has not been intensified. Control of agricultural pollution in these provinces has shown a positive and significant impact on public health. In selected provinces, the cleaner agricultural products and application of organic fertilizers have been increased. This study results also showed that the climate change will accelerate increment of pests population and thus pesticides application in different climatic regions. [ABSTRACT FROM AUTHOR]

Air pollution around refineries and factories is one of the major environmental challenges affecting forest ecosystems' health. Although there have been many studies on Iran's forest ecosystems, the physiological and morphological responses of Brant's oak (Quercus brantii Lindl.) leaves to the pollution of the gas refineries in the semiarid forests have not received much attention. We sampled healthy and mature leaves from four oak stands in different seasons (spring, summer, and autumn of 2019) and at various distances from the gas refinery (1,000, 1,500, 2,000, 2,500, and 10,000 m). The results showed that oak trees in different seasons and at different distances from the refinery had different physiological and morphological leaf trait responses to the pollution source. Oak trees with an air pollution tolerance index value of less than 11 were in a sensitive range to air pollution and can be used to biomonitor air pollution around the gas refinery in Zagros forests. Physiological traits in different seasons and at various distances in comparison with morphological traits (persistent reaction responses) were well distinguished from one another and were more affected by pollution. Oak trees in summer and autumn and at distances up to 2,500 m had rapid reaction responses, including oxidative stress indicators such as electrolyte leakage (EL), hydrogen peroxide, and different enzymatic and nonenzymatic antioxidants such as phenol, flavonoids, catalase, and proline. Because of their high sensitivity to atmospheric pollutant stresses, we recommend that these traits be used for rapid and low-cost environmental monitoring of pollution in different seasons and distances from pollution sources in semiarid ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: The Power Plants Generation Planning (PPGP) usually encountered complicated problems. In this paper, a new hierarchical approach is applied for generation planning in power plants. In hierarchical approach, the main integrated problem is separated into some sub problems which could be easily solved by multi level models. Higher level models include organization total strategy and lower level models is concerned with detailed accurate planning. When models are broken down into several levels, the solutions of higher level could be considered as inputs for the lower levels. In the proposed structure, amount of future demand is predicted to specify time periods in first level. In the second level, amount of demand for each aggregate period is allocated to different aggregate methods of electricity generation like; steam, gas, combined cycle and hydro power plants in Iran by using Analytical Hierarchy Process (AHP) and Fuzzy Aggregate Production Planning (FAPP). This allocation is carried out according to two criteria of “share of total electricity generated by each type of generation” and “amount of environmental pollution”. AHP and Fuzzy Disaggregate Production Planning (FDAPP) are applied to determine best utilizing power plants for generation in the final level. The proposed Fuzzy Hierarchical Production Planning (FHPP) outputs express optimal combination of power plants which contribute for demand satisfaction. [Copyright &y& Elsevier]

The present study was done to analyze and compare synoptic conditions during the most durable pollution and clean waves (MDPW and MDCW) in Tehran City (capital of Iran). For this purpose, air quality index (AQI) data were first obtained during 2009–2019 from the Tehran Air Quality Control Company in Tehran Province. Then, a threshold of (AQI ≤ 101) representing a polluted and unhealthy atmosphere was considered as MDPW, and a threshold of (AQI ≤ 50) representing a clean (good) air was selected as MDCW in Tehran City by identifying the polluted days. The results showed the presence of MDPW during 43 polluted days from November 21, 2010 to January 2, 2011. Intensity and frequency of the polluted days during statistical period showed a decreasing trend that coincided with an increasing trend of precipitation. Analysis of synoptic conditions occurred during 43 days of MDPW indicated penetration of Siberian high-pressure from the east at sea level and extension of sub-tropical anticyclone in mid-level from the west that led to development of an anticyclone circulation with descending and converging flow in Iran and surrounding region. As a result, a calm and sustainable climate and stable concentration of pollutants were observed throughout Tehran City. Backward trajectory of sources and entry route of the polluted air to Tehran City during peak days of pollution showed that desert regions of southern Iraq and central Iran along the southern and southwestern parts played a major role in increasing concentration of pollutants during occurrence of durable wave. Different routes were observed in entry of dusty and the polluted air to Tehran City according to hybrid single-particle Lagrangian integrated trajectory (HY SPLIT) model, but in most of peak days, the areas that were near and adjacent to Tehran City with height of less than 1000 m played a greater role in particle transport. Investigation of instability indices during MDPW showed that in most days of pollution, values of instability intensity were classified into weak class and lower troposphere (1000–850 hPa) compared to higher levels, and degree of stability and calmness of the atmosphere was more. So that, the highest frequency of temperature inversions occurred near the earth's surface. [ABSTRACT FROM AUTHOR]

Environmental pollution is a world-wide problem, heavy metals belonging to the most important pollutants. The progress of industries has led to increased emission of pollutants into ecosystems. Karoon is the biggest and only navigable river in the South of Iran. Along the Karoon industrial units such as piping, steel, paint making, agriculture, paper mill, fish cultivation, abbottiors, electroplating industries drain their wastewater into the river. In this study, the concentrations of heavy metals (Ni, Cr, Cu) in the Karoon river have been determined. Samples were collected from 16 stations along the river, in winter and spring 1996. Heavy metal concentrations were measured by graphite furnace atomic absorption spectrometry. The minimal and maximal concentrations of these metals in winter were 69.3–110.7, 1.7–118.3, and 5.5–70.3 μg/l, for Ni, Cr, and Cu, respectively. The minimal and maximal concentrations of these metals in spring were 41.0–60.7, 0.7–19.8, and 0.5–28.7 μg/l, for Ni, Cr, and Cu, respectively. The results show that the pollution has increased along the river, down to the estuary at the Persian Gulf. [Copyright &y& Elsevier]

Infantile methemoglobinemia, thyroid disorders, and probably some carcinogenic effects are health concerns associated with dietary nitrate. Isfahan province has a dry and semi-arid desert climate such that the main source of various applications in this province is groundwater resources. This study evaluated spatial analysis of the groundwater NO3− concentrations and its possible health risk to residents. Method 8171 Hach was used for nitrate measurement of 1319 groundwater samples from March 2018 to February 2019. Non-carcinogenic risk due to NO3− exposure through consumption of drinking water was assessed, and the associated zoning maps were presented using geographic information system (GIS). Nitrate concentrations in the rural and urban areas were within 0.4–137 mg/L NO3− and 2.9–209 mg/L NO3−, respectively. Also, 226 (25%) and 104 (24%) of samples in the rural and urban areas, respectively, were detected above the Iran and WHO guideline NO3− values of 50 mg/L. The highest levels of NO3−, which were found in the western and central groundwater resources, occurred in the agricultural and residential areas. The NO3− concentrations were higher in urban than rural areas in the many studied counties. Also, nitrate was higher in wet seasons than in dry ones. Infants' non-carcinogenic risks were higher than the other groups. Infants (HQ > 1) were the most vulnerable group compared with the other groups in some counties. Thus, there are potential risks of methemoglobinemia, especially for infants. It is critical to adopt specific strategies to reduce the nitrate concentration in the studied groundwater. [ABSTRACT FROM AUTHOR]

The pollution of Iranian agricultural soils with trace elements (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) was assessed and compared with other agricultural soils around the world. Experimental data on trace element content in Iranian agricultural areas in the west and north were collected from the literature: 39 studies covered a total of 46 agricultural sites of 17 provinces in Iran, in order to characterize their patterns of accumulation of trace elements. Two pollution indices, namely, the pollution index (PI) and the integrated pollution index (IPI), were used to evaluate trace element accumulation. The data revealed a remarkable variation in trace element content among soils in different areas. Exploratory data analyses (EDAs) showed that a number of trace elements (Pb, Cu, and Zn) are asymmetrically distributed and scattered. Surveys indicated that 45.5% of the studied samples had elevated PI values for Cd, 13.0% for Cu, and 16.7% for Pb, clearly indicating an anthropogenic contribution of these three elements. The IPI of the agricultural soils also indicated that most areas are classified as having moderate and high pollution. Higher contents of trace elements (except for Mn) were found in some cities of the Isfahan, Hamadan, and Tehran provinces. Excessive application of conventional and organic fertilizers, pesticides, animal manure, and sewage sludge for enhancing crop production is responsible for high trace element content in Iran's agricultural soils. This in turn, through the food chain, is a threat to human health. Analysis of the correlation between trace elements exhibited that Cu, Pb, and Zn (Cd, Pb and Zn) were very closely associated with each other, showing that their prevalent sources are common and the efforts to regulate them linked in common actions. We consider this evaluation as a viable approach to other similar areas in the Middle East and beyond, which could be used by environmental scientists for risk assessment and decision making. [ABSTRACT FROM AUTHOR]

The current study was done to evaluate the pH, electrical conductivity, bulk density, sand, silt, clay, available K and P, organic carbon, Zn, Cu, Mn, and Fe in agricultural soils of Alborz province, Iran. A total of 46 samples were collected as composite samples from 0–20 and 20–40 cm soil depths. The average values of Fe, Cu, Mn, and Zn were found lower than the European limits, Indian limits, and Earth's crust. Pearson's correlation analysis found that pH effects Zn retention and, Cu and Mn retention in soil samples. Cluster analysis and Principal component analysis established that HMs are originated from different sources. Contamination factor (CF) and ecological risk index (RI) results showed less contamination and ecological risk in soil samples. Enrichment factor (EF) and modified ecological risk index (MRI) results indicated high enrichment and ecological risk of Cu, Mn, and Zn in surface and sub-surface soil samples. [ABSTRACT FROM AUTHOR]

The study area is the Southern Caspian Sea. Three rivers, Chalous, Sardabroud and Namak Abroud, are effective in this area. Sediment loads carried by these three rivers are the source of environmental pollution in this area's seabed sediments. To identify environmental pollution in this research, a total amount of 80 samples were collected from sediment of the sea and the rivers. By measuring the amount of As, Cd, Co, Cr, Cu, Ni, Pb and Zn in these sediments, one can determine the pollution pattern in this area by calculating environmental indicators such as: Geoaccumulation Index, Enrichment Factor, Contamination Factor and Pollution Load Index. Granulometry experiments show that sedimentary facies are divided into two main groups: sand and mud. The amount of Geoaccumulation Index is unpolluted. Enrichment Factor of river and shallow water sediments, the amount of As, Cd, Pb, Zn is in the high to medium category and the amount of Co, Cr, Cu and Ni is in the low category. Contamination Factor shows that river and shallow water sediments are very high to low ranking. Pollution Load Index is showing heavy metal contamination in the river and shallow water sediments. Statistical studies reveal the relationship between the pollution indicators and the amount of elements more effectively. The concentration of heavy metals in river sediments is more than in marine sediments due to the use of pesticides and chemical fertilizers in agricultural lands. The results of contamination indicate their anthropogenic origin and the lithological does not in the production of environmental pollution. [ABSTRACT FROM AUTHOR]