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To address the problem of petrochemical organic pollutants in water, specifically monoethylene glycol (MEG) present in industrial process streams, in this research, we synthesized and evaluated a multifunctional nanocomposite, Fe3O4@MC/MWCNT-CuO/Ag. The nanocomposite was produced by combining magnetic Fe3O4 nanoparticles, methylcellulose (MC), multi-walled carbon nanotubes (MWCNTs), and CuO/Ag nanoparticles by an integrated synthesis process. A consistent dispersion of nanoparticles, with diameters ranging from 30-40 nm, was discovered by FESEM analysis, showing effective integration without aggregation. Effective synthesis was demonstrated by well-doped and evenly dispersed CuO and Ag nanoparticles. Functional groups that improve electrostatic interactions with contaminants hence enhancing catalytic performance and adsorption efficiency, were validated by FTIR analysis. XRD indicated an unchanged crystal structure with an average crystallite size of 8.67 nm. The anticipated elemental composition was verified by EDS & mapping. A VSM study revealed magnetic characteristics (9.33 emu/g) that simplify nanocomposite separation and reuse. TGA proved thermal stability to be up to 600 °C. A BET study showed a highly specific surface area of 67.661 m2/g, enhancing adsorption. According to DRS and PL studies, the bandgap was lowered by 1.31 eV, which led to better optical absorption. The nanocomposite exhibited notable MEG removal efficiency, with 72 % in adsorption, 65 % in photocatalysis, and 56 % in sonocatalysis. This makes it a promising alternative for the remediation of organic pollutants in water treatment.

Addressing the urgent need to effectively manage landfill leachate as a harmful flow for human health and the environment, this research investigates how electrocoagulation (EC) processes could alleviate the pollution potential of leachate. So far, no experimental study has been carried out on reducing the leachate pollution index (LPI) under the EC process. For this purpose, in this novel research, the LPI was utilized as a key metric to evaluate the efficiency of the treatment process. Central Composite Design (CCD) as a subset of Response Surface Methodology (RSM) was applied to enhance the LPI parameters decreasing percentage. The data were analyzed by analysis of variance and multivariate regression and 3D plots assessed variable interactions. Under optimal conditions, it showed removal of 97.48 % for COD, 91.42 % for BOD5, 98.52 % for N-NH3, and 91.6 % for TDS. Significant reductions were observed in 94.81 % TKN, 87.20 %, 82.80 %, 96.66 %, and 99.28 %, 99.18 %, and 96.56 % for TKN, Cl−, CN−, As, Cr, Zn, and Ni, respectively. Moreover, the kinetics of COD removal indicated that it follows a first-order model. Thus, based on experimental results, the LPI of raw leachate decreased from 38.06 to 7.22 (81 % decrease) under the EC treatment method. The study indicated that the EC treatment method successfully reduced leachate pollution and met the leachate discharge standard.

The migratory lifestyle of nomadic communities, combined with the lack of a suitable health-related organizational structure, has made it difficult to provide health care services that can improve their health status. To achieve the concept of justice in health and sustainable development, it is imperative to improve the health status of all citizens in Iran, which consists of the nomadic communities, and urban and rural populations. In this ecological study national health indexes in nomadic tribespeople was Identified and prioritized by expert panel and fuzzy Delphi method. In the first step, the national health indexes were extracted from the literature, and then indexes that can be measured, evaluated and representative of the nomadic communities were extracted and prioritized by using fuzzy Delphi and TOPSIS methods, Questionnaire options were analyzed according to 3 criteria of economic efficiency, measurability, and simplicity in the form of 13 components and their indicators. The analysis of the results of the fuzzy Delphi method shows that the mental health component has the lowest real score in the criteria of measurability, simplicity and economic efficiency. The child care component has the highest real score in terms of economic efficiency and the vaccination component has the highest real score based on the criteria of measurability and simplicity in nomadic communities. The results of the TOPSIS method show that the components of vaccination, maternal care and child care have the highest priority for attention and investigation of their indicators in this segment of the population. In general, by designing and implementing systems to record the information of priority indexes extracted from the present study, it is possible for responsible organizations to make effective decisions and plans for the improvement of the health status of nomadic communities.

Abstract Exposure to heavy metals in contaminated drinking water is strongly correlated with various cancers, highlighting the burden of disease. This study aimed to assess the non-carcinogenic and carcinogenic risks associated with exposure to heavy metals (As, Pb, Cd, and Cr) in drinking water of Fars province and evaluate the attributed burden of disease. Non-carcinogenic risk assessment was performed using the hazard quotient (HQ) method, while the carcinogenic risk assessment utilized the excess lifetime cancer risk approach. The burden of disease was evaluated in terms of years of life lost, years lived with disability, and disability-adjusted life years (DALY) for three specific cancers: skin, lung, and kidney cancer. The average drinking water concentrations of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) were determined to be 0.72, 0.4, 1.10 and 0.72 μg/L, respectively. The total average HQ of heavy metals in drinking water in the study area were 0.127, 0.0047, 0.0009 and 0.0069, respectively. The average ILCRs of heavy metal in the entire country were in the following order: 1.15 × 10−5 for As, 2.22 × 10−7 for Cd and 3.41 × 10−7 for Cr. The results also indicated that among the various counties analyzed, Fasa experiences the greatest burden of disease in terms of DALYs, with a value of 87.56, specifically attributed to cancers caused by exposure to arsenic. Generally, it can be said that the burden of disease is a critical aspect of public health that requires comprehensive understanding and effective intervention.

In the study, the proliferation of industries has been associated with an increase in the production of industrial wastewater and subsequent environmental pollution, wherein dyes emerge as prominent pollutants. The characteristics of nanoclay modified with octadecylamine, were elucidated throughvarious techniques, including Field Emission Scanning Electron Microscopy/Energy Dispersive Spectroscopy (FE-SEM/EDS), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD), and Brunauer-Emmett-Teller Surface Area Analysis (BET). The research delved into the impact of variables such as pH, initial dye concentration, adsorbent dose, temperature, and ultrasonication time on the removal of Acid Black 1 (AB1) through an ultrasonic process, employing a central composite design (CCD). Optimal conditions for the adsorption process were determined: pH at 5.46, adsorbent mass at 4 mg/30 mL, initial dye concentration at 20 mg/L, ultrasound time at 20 min, and temperature at 50 °C, resulting in a remarkable 96.49% adsorption efficiency. The fitting of experimental equilibrium data to different isotherm models, including Langmuir, Freundlich, and Temkin, indicated thatthe Freundlich model was the most suitable. Analysis of the adsorption data with various kinetic models such as pseudo-first and second-order models, and intraparticle diffusion models, revealed the applicability of the second-order equation model. A thermodynamic study unveiled that the adsorption process was spontaneous and endothermic. In conclusion, the study highlights the significant capability ofmontmorillonite nanoclay modified with octadecylamine in removing AB1 dye, rendering it a viable option for wastewater treatment.

Abstract Widespread use of benzophenones (BPs), a group of environmental phenolic compounds, is suspected of interfering with human health. The association of prenatal exposure to benzophenone derivatives with birth outcomes including birth weight and length, head, arm and thoracic circumference, abnormalities, corpulence index and anterior fontanelle diameter (AFD) was investigated. Mother-infant pairs of 166 within PERSIAN cohort population in Isfahan, Iran, in the 1st and 3rd trimesters of pregnancy were assessed. Four common benzophenone metabolites including 2,4-dihydroxy benzophenone (BP-1), 2-hydroxy-4-methoxy benzophenone (BP-3), 4-hydroxy benzophenone (4-OH-BP) and 2,2′-dihydroxy-4-methoxy benzophenone (BP-8) were measured in maternal urine samples. The median concentration of 4-OH-BP, BP-3, BP-1 and BP-8 were 3.15, 16.98, 9.95 and 1.04 µg/g Cr, respectively. In the 1st trimester, 4-OH-BP showed a significant correlation with AFD in total infants, decreasing 0.034 cm AFD per a log unit increase of 4-OH-BP. Within the male neonates, 4-OH-BP in the 1st and BP-8 in the 3rd trimester were significantly associated with head circumference and AFD increase, respectively. Among female neonates in the 3rd trimester, increasing 4-OH-BP and BP-3 concentration was correlated with a decrease in birth weight and AFD, respectively. This study demonstrated that all the target BP derivatives can influence normal fetal growth at any age of the pregnancy, nevertheless, to support these findings further studies are needed in a large and different group population.

Abstract Polycyclic aromatic hydrocarbons (PAHs) are often formed when organic substances do not burn completely. This study evaluates the non-carcinogenic and cumulative risks associated with PAHs levels by testing blood and urine samples in kitchen workers and residents near restaurants in Shiraz, Iran. Metabolites of PAH in the urine samples as well as clinical parameters in the blood samples were measured. The non-carcinogenic and cumulative risk assessments from exposure of the study groups to PAH metabolites were also evaluated. The highest average concentrations of PAH metabolites were related to kitchen workers (2126.7 ng/g creatinine (ng/g cr)). The metabolites of 1-Hydroxypyrene (1-OHP) and 9-Phenanthrene (9-OHPhe) had the highest and lowest mean concentrations, respectively. A direct correlation was observed between the levels of PAH metabolites with malondialdehyde (MDA) and total antioxidation capacity (TAC) levels (p

Abstract Diesel oil is known to be one of the major petroleum products that can pollute water and soil. Soil pollution caused by petroleum hydrocarbons has substantially impacted the environment, especially in the Middle East. In this study, modeling and optimization of hexadecane removal from soil was performed using two pure cultures of Acinetobacter and Acromobacter and consortium culture of both bacterial species using artificial neural network (ANN) method. Then the best ANN structure was proposed based on mean square error (MSE) as well as correlation coefficient (R) for pure cultures of Acinetobacter and Acromobacter as well as their consortium. The results showed that the correlations between the actual data and the data predicted by ANN (R2) in Acromobacter, Acinetobacter and consortium of both cultures were 0.50, 0.47 and 0.63, respectively. Despite the low correlation between the experimental data and the data predicted by the ANN, the correlation coefficient and the precision of ANN for the consortium was higher. As a result, ANN had desirable precision to predict hexadecan removal by the cobsertium culture of Ochromobater and Acintobacter.

Introduction: Environmental and structural factors have a significant effect on the concentration of bioaerosols in the indoor air; however, this issue has not received enough attention in research. . Therefore, this study aimed to determine the distribution of bioaerosols and environmental factors affecting the concentration of bioaerosols by using an artificial neural network.Methods: In this study, the concentration of bioaerosols was determined using the inactive method for one hour in the human respiratory tract. The teypticas soy agar and sabouroud dextrose agar were used to culture bacteria and fungi; then, they were incubated at 15, 25, and 37° C. The independent variable includes three categories of structural variables (number of ward beds, room dimensions, and window dimensions), hospital management and management variables (ward air change per hour), and analytical variables (incubation temperature and type of culture medium). The effect of these variables was modeled by an artificial neural network with Levenberg–Marquardt algorithm.Results: This study showed that the distribution of bioaerosols in dialysis and surgery wards was higher than in other wards. Also, the artificial neural network can predict the effect of environmental and structural factors of the hospital on bioaerosols, especially fungi because the maximum and minimum concentrations of bacteria and fungi in the actual data were similar to the data predicted by the artificial neural network. In addition, the correlation coefficient for the fungi was 0.95, and the correlation rate between the actual data and the data predicted by the artificial neural network was higher than 0.92.Conclusion: ANN could be a desirable and reliable method for detecting bioaerosol in hospitals based on the environmental and structural parameters.

Abstract The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay is the most common method for the determination of cell toxicity, but some factors limit the sensitivity of this method, such as pH. Less attention had been paid to the interference effect of optical and plasmonic properties of SiO2 nanoparticles (NPs) in the wavelength range assigned to MTT. This study investigated the synergistic interference effect of SiO2 NPs and wavelength on MTT assay for the first time. The examined variables included the type of SiO2 NPs concentrations (1, 10, and 100 mM) and different wavelengths (470, 490, 520, and 570 nm). The results showed that optical density (OD) increased (p 0.05). According to polynomial regression modeling (PRM), the maximum interference effect was predicted at crystalline SiO2 NPs and wavelength > 550 nm. Besides, the synergistic effects of SiO2 NPs, wavelength, and concentration of NPs had been a good fitting with first-order PRM. Thus, the concentration of SiO2 NPs had a confounder factor in colorimetric for MTT assay. The best artificial neural network (ANN) structure was related to the 3:7:1 network (Rall = 0.936, MSE = 0.0006, MAPE = 0.063). The correlation between the actual and predicted data was 0.88. As SiO2 NPs presence is an interfering factor in MTT assay concerning wavelength, it is suggested wavelength use with minimum confounding effect for MTT assay.

Introduction: Air pollution from industrial sources is a growing problem increasing the amount of air pollution by emitting various gaseous pollutants such as Nitrogen Oxides (NOx). This study analyzed Nitrogen dioxide (NO2) emissions using American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) from the stacks and flares of a gas refinery in the Middle East. Materials and methods: The NO2 emissions were measured from the stacks and flare of the refinery (231 samples). The distribution of emissions was investigated over a statistical period of 1 year for an average time of 1 h using the AERMOD dispersion model in an area of 25×25 km2. The predicted concentrations were compared with national and international standards and are plotted for the desired zones. Results: Comparison of simulation results with national and international clean air standards showed that NO2 emission modeled in all periods of 4 seasons is higher than the standard. Examination of NO2 emission and distribution maps also showed that the maximum concentration of NO2 pollutants occurred in the central parts and the area close to the refinery. The highest maximum concentration of 1-h NO2 was 3744.3716 μg/m3 in summer in the west and south of the refinery. Validation results also showed a high correlation between the predicted and actual results. Conclusion: The power of resources in emission and distribution, topographic conditions, and meteorological characteristics of the region are three important and influential factors in the distribution of NO2 pollutants. So pollution reduction strategies are needed due to the different types of use, surrounding residential areas, personnel, and people involved in the gas refining company.

Background and Objective: The aim of this study was to investigate the effect of seasonal variation on the diversity of fungal airborne species in the composting process. Materials and Methods: Samples were taken based on the 0800 NIOSH method at a height of 1.5 m above the ground during the waste separation, turning of windrow and stabilization of compost. Air samples were collected in two various seasons; summer (108 samples) and winter (108 samples) at the composting plant in Shiraz. The culture media consisted of Sabouraud Dextrose Agar with chloramphenicol for the selective isolation of fungi, which was further incubated at 37 and 45°C. The results were analyzed by a t-test method using MATLAB 2018. Results: The highest mesophilic fungi density was related to the segregation process of composting. The variation of fungi observed was higher during summer throughout separation and stabilization process (p < 0.05). The predominant species were found to be Aspergillus flavus (4449.8 CFU/m3) (p < 0.05) and Paecilomyces (1850.9 CFU/m3) (p < 0.05), respectively. Furthermore, the highest varieties of fungal species in the turning of windrow mass were observed during winter (p < 0.05) and the predominant species was yeast (420.6 CFU/m3). At all stages of composting, the varieties of thermophilic fungal species were higher during summer with the large number of Aspergillus fumigatus, Mucoral, and Paecilomyces. Conclusion: The density and diversity of mesophilic fungi during summer was higher than winter. The concentration of Aspergillus, was beyond the guidelines set by the EPA, ACGIH, NIOSH and EU. Thus, the use of self-protection is essential.

Background: Discharging antibiotics into the environment could cause great concern for scientists. In the present study, tetracycline (TC) antibiotic was photodegraded with titanium dioxide (TiO2) and zinc oxide (ZnO) fixed on the polyurethane (PU) in the presence of ultraviolet (UV) irradiation and optimized through response surface methodology (RSM). Methods: This experimental study was conducted on the most effective variables (pH, contact time, TC concentration, and catalyst doses) for experimental design. The experiments of degradation with the process of PU/UV/nanocatalyst composite were conducted with a reactor glass vessel (1000 mL) as batch mode. Results: The results showed that the quadratic model can be used for the interpretation of experiments. The results of the model represented that all parameters had a significant effect on the tetracycline removal, and the degradation of antibiotics was obtained at the optimum condition that was 95% for ZnO/UV/PU and 97% for TiO2/UV/PU. The main radical for the degradation of TC was hydroxyl ions based on the scavenger study and the first-order kinetic model was best fitted with data. The highest removal efficiency was obtained at pH of 5.2, catalyst dose of 2.64g/m2, TC concentration of 25.21, reaction time of 82 min using ZnO/UV/PU and pH of 5.8, catalyst dose of 2.9 g/m2, TC concentration of 25.12, and reaction time of 90 min using TiO2/UV/PU. Conclusion: It could be concluded that the process of nanocatalyst fixed on polyurethane can significantly eliminate the antibiotic in the presence of ultraviolet irradiation from the effluent of the wastewater treatment plant.

Introduction: Hospitals, as one of the important elements in the health system, play an important role in patient’s health. Fungi are one of the effective parameters on indoor air quality. This study aimed to compare of fungal contamination of two hospitals in Shiraz City. Materials and Methods: Sampling was conducted based on NIOSH 0800 standard (1.5 meters above the ground level with one stage Anderson and Sabaroud dextrose agar enriched chloramphenicol as the growth media) in January-September 2017. The investigated wards included pathological laboratory, emergency rooms, neonatal specialist care, radiology, operating room, and maternity ward. The results showed that the variation and concentration of fungi were higher in hospital X than hospital Y, which was located in an agricultural area far from the city center. Results: The predominant fungi were Monillia, Aspergillus, and Penicillium in hospital Y, while they were Aspergillus and Penicillium in hospital X. The highest concentrations were found in emergency and laboratory wards. With regard to higher fungal contamination of hospital X and its different location, it can be concluded that the geographical properties and outdoor air are effective factors on indoor air contamination at hospitals. Conclusion: Appropriate management of patients' admission and visiting time can be effective on indoor air contamination at hospitals. Furthermore, efficient ventilation using high-efficiency particulate air and appropriate devices for elimination of fungi level are recommended to this end. Moreover, these parameters can provide physical and psychometric health problems for patients’ careers and other health workers.

Introduction: Pyrene and phenanthrene are polycyclic aromatic hydrocarbons (PAHs) are priority pollutants. The aim of this study was to investigate the ability of isolated bacteria from stabilized compost‌ for biodegradation of pyrene and phenanthrene from soil contaminated with municipal solid waste leachate. Materials and Methods: In this study, phenanthrene and pyrene were selected as priority PAHs pollutants. The degrading bacteria of these compounds were isolated from the stabilized compost and their ability to remove different concentrations of pyrene and phenanthrene investigated. The remaining concentrations of pyrene and phenanthrene were measured by GC-MS. The growth kinetics of bacteria were also studied using a spectrophotometer at 595-nm wavelength. One-way ANOVA was used to determine the statistical significance and plot the related curves, and the Excel software and SPSS version 24 to do statistical analysis. Results: The most potent bacteria in removing pyrene and phenanthrene were Paenibacillus and Bacillus, respectively. The concentrations to be studied were determined as 10, 25, 40 and 55 μg/kg according to the concentrations of PAHs in the soil contaminated with municipal solid waste leachate. At constant temperature of 30 °C after 30 days at these concentrations, the removal efficiency was, respectively, 96.3%, 83%, 77.8%, and 72.4% for pyrene and 100%, 99.6%, 95.9%, and 94.6% for phenanthrene. The growth kinetics of phenanthrene-exposed bacteria were better than those of pyrene-exposed bacteria. Conclusion: The results show that bacteria in stabilized compost are able to remove pyrene and phenanthrene. The bacteria of the highest efficiency for removal of pyrene and phenanthrene are Paenibacillus and Bacillus, respectively.

Abstract System dynamics is considered as a computer-aided approach to policy analysis and design. It includes the response and reaction of a system to external shocks. In the present research, following the sampling and testing phases, a system dynamics model was developed for modeling of phosphorus in facultative stabilization ponds. First, the scheme of soluble reactive phosphorous stock, its specifications and parameters were determined and created in the VenSim PLE 7.1 software. Then, mathematical relations were determined for each process. Finally, the model was calibrated and verified based on the data from the Yazd facultative ponds, Iran. Sensitivity analysis showed that the most important factors affecting phosphorus concentration in the ponds are the phosphorus settling rate, losses caused by algal respiration and excretion, while the losses caused by herbivorous zooplanktons, hydrolysis rate of inorganic carbon, and ratio of phosphorus to chlorophyll-a had the least importance. Results showed that, algal growth rate and phosphorus settling rate were important factors in phosphorus removal. Hence, with appropriate retention time in the pond, it can be managed more properly. The ratio of phosphorus to algae had less importance in the model. The ratio of carbon to phosphorus and rate of respiration of carnivorous zooplanktons did not affect the phosphorus concentration. It is recommended that this model can be used for pond management and overall assessment of facultative ponds.

Drinking water sources may be polluted by various pollutants depending on geological conditions and agricultural, industrial, and other human activities. Ensuring the safety of drinking water is, therefore, of a great importance. The purpose of this study was to assess the quality of drinking groundwater in Bardaskan villages and to determine the water quality index.Water samples were taken from 30 villages and eighteen parameters including calcium hardness (CaH), total hardness (TH), turbidity, pH, temperature, total dissolved solids (TDS), electrical conductivity (EC), alkalinity (ALK), magnesium (Mg2+), calcium (Ca2+), potassium (K+), sodium (Na+), sulphate (SO42−), bicarbonate (HCO3−), fluoride (F−), nitrate (NO3−), nitrite (NO2−) and chloride (Cl−) were analyzed for the purpose for this study. The water quality index of groundwater has been estimated by using the ANFIS. The spatial locations are shown using GPS. The results of this study showed that water hardness, electrical conductivity, sodium and sulfate in 66, 13, 45 and 12.5% of the studied villages were higher than the Iranian drinking water standards, respectively. Based on the Drinking Water Quality Index (DWQI), water quality in 3.3, 60, 23.3 and 13.3% of villages was excellent, good, poor and very poor, respectively. • Groundwater is one of the sources of drinking water in arid and semi-arid regions such as Bardaskan villages, which monitor the quality of these resources in planning for improving the quality of water resources. • The DWQI can clearly provide information associated with the status of water quality resources in Bardaskan villages. • The results of this study clearly indicated that with appropriate selection of input variables, ANFIS as a soft computing approach can estimate water quality indices properly and reliably. • Some parameters were in the undesirable level is some villages. Therefore, the government should try to improve the chemical and physical quality of drinking water in these areas with the necessary strategies. Protocol name: Estimation a water quality index in Bardaskan city, Keywords: Drinking water, WQI, Bardaskan villages, Iran

Introduction: Hospitals are one of the main water consumers in urbane area. Due to lack of enough information, the challenges and some of the solutions were investigated for optimization of water management. Materials and Methods: This study was a cross-sectional study in a Shiraz educational hospital. Data were collected by questionnaires with 146 items. The items was classified in several steps; (1) determination of present situation; (2) identification of challenges in water management; (3) identification of opportunities for reducing water consumption; (4) writing several practical scenarios; (5) cost-benefits analysis for each scenarios; (6) providing the results to the hospital for decision-making. Scenarios were including: installation of a bottle 1.5 litters in toilet flushing, substitution of water cooling with mixture ventilation system (natural and artificial air conditioning system), reuse of regeneration water from cation exchanger, substitution of flooding irrigation with dropping system, using the native or adaptable plants with dry climate. Results: According to the results, 48488 m3/month water was required; however, it was 431125 and 12491500 m3/month in winter and summer (present situation). The cost-benefit of scenario 1,2,3,4 and 5 were 960,170,2370000,13500 and 7500 USD, respectively. Moreover, the investment repayment were 4 years, 1 month, 3.06 years, lower than 1 month, and 3.8 years, respectively. Conclusion: Water consumption was 8-200 times higher than really water demand. It could be result of traditional distribution system and improper management. The scenario 4 was the best alternative for this hospital. Since the cost-benefit ratio to investment repayment period was higher than others.

Background: Simultaneous existence of excessive amounts of fluoride and nitrate in drinking water can cause health problems for humans. In this study, simultaneous removal of fluoride and nitrate from aqueous solutions was investigated using a combination of electroreduction and electrocoagulation processes in a batch reactor with different electrodes. Methods: In this study, at first, an optimum electrode was selected. Afterward, the effects of different operating parameters such as the current density (12- 36 mA/cm2), initial pH (5.5-8.5), NaCl concentration (0.5-1.5gr/L), and electrolysis time (15-120 min), ) on the removal of fluoride (initial concentration: 6 mg/L) and nitrate (initial concentration: 150 mg/) were evaluated, respectively. Results: The highest efficiency of the concurrent fluoride and nitrate removal with Al-Cu electrode and in optimal experimental conditions of the current density of 36 mA/cm2, pH of 7, NaCl concentration of 1gr/L, and electrolysis time of 90 minutes was obtained 87.04 and 89.70%, respectively. Conclusion: High catalytic activity of the copper cathode resulted in better performance than other cathodes in the simultaneous removal of fluoride and nitrate. Generally, it can be concluded that the electrochemical process can reduce the levels of fluoride and nitrate to the amounts below the WHO standard limits, 1.5 mg/L and 50 mg/L, respectively.

Introduction: Cutaneous leishmaniasis can lead to the loss of time, labor force, significant treatment costs and psychological problems. Also, cutaneous leishmaniasis is considered as an important health problem in Iran. This study was aimed at investigating the status of cutaneous leishmaniasis in Dashtestan district. Materials and Methods: This cross-sectional and descriptive-correlational survey was performed on all confirmed leishmaniasis cases (86 person) following up in Dashtestan district health care centers during 2013-2014. Patient’s general information such as age, sex, geographical region, number and site of ulcer, as well as the month and season of incidence were registered and analyzed by SPSS ver.24. All ethical issues were also addressed. Results: During 2013, the maximum percent frequency of the incidence of cutaneous leishmaniasis was related to the age-group of 0-4 years (41.9%) and during 2014, was related to the age group of 15-24 years (30.2%). During 2013 and 2014, the incidence of cutaneous leishmaniasis was higher in males than in females and the face was the most common site of the ulcer. During 2013 and 2014, autumn and winter had the most seasonal incidence and most of the cases were observed during September and January, respectively. Conclusion: Based on the study results, cutaneous leishmaniasis is high endemically in Dashtestan district. Therefore, control measures such as education, optimizing the environment and the application of appropriate coating for exposed age groups, especially children and young people are essential.

Background:Discharge of raw or treated wastewater containing linear alkyl benzene sulfonate (LAS) into the environment causes significant public health and environmental problems. The purpose of this study was the treatment of hospital wastewater using an intermittent cycle extended aeration system (ICEAS).Methods:Experiments were carried out on Yazd Shohaday-e-Kargar hospital wastewater treatment system and samples were collected in a 2 month period from the influent and effluent of the system. The used pilot study carried out consisted of two zones: pre-react and main react zones. They were divided using a baffle wall. Firstly, wastewater enters a pre-react zone and then through the opening at the bottom of the baffle wall it enters the main react zone. The cycle time and flow rate for the system were considered 6 h and 2 L/h, respectively. Then, the necessary tests were performed on the system’s influent and effluent.Results:The removal of BOD5, COD, and LAS by ICEAS were 94.54%, 92.97%, and 84.99%, respectively. The averages of SVI, F/M, MLSS and MLVSS in the system were 113 mL/g, 0.086 Kg.BOD5/Kg.MLSS.d, 4327 mg/L and 3172 mg/L, respectively.Conclusions:This work showed the excellent efficiency of ICEAS to effectively remove BOD5, COD, and LAS from hospital wastewater. The results of this research can help to manage wastewater treatment in hospitals.

Background: Atrazine is a widely used herbicide. The increasing salinity of many water resources has had a negative effect on atrazine biodegradation. The aim of this study was to isolate atrazine degrading bacteria in semi-salinity media. Methods: Nine selected bacterial species were cultivated on the mineral salt broth culture medium containing atrazine (50, 100, 500 mg/L), NaCl concentration (10 g/L), and 2% (wt/vol) agar. The bacteria with higher growths in the atrazine medium (500 mg/L) were selected. Then, those with higher growths were transferred to the medium with atrazine concentration of 1000 mg/L. The atrazine biodegradation rates by Ochrobactrum oryzae and consortium bacteria (all of the nine bacteria species) were compared by cultivating separately on the mineral salt broth containing atrazine concentration of 30 mg/l, and NaCl concentration of 10 g/L in the incubation time of 10 day and HPLC analysis. Results: The results indicated that Ochrobactrum oryzae had the highest growth compared to the other investigated bacteria (Acinetobacter radioresistens, Paenibacillus lautus, and Bacillus sp) in the mineral salt broth culture medium containing atrazine concentrations (1000 mg/L), NaCl (10 g/L), and 2% (wt/vol) agar. In the Ochrobactrum oryzae and bacterial consortium comparison, atrazine biodegradation rate in the culture medium containing NaCl, by Ochrobactrum oryzae, was higher than bacterial consortium and atrazine biodegradation rate in the culture medium with no NaCl addition, by Ochrobactrum oryzae, was lower than bacterial consortium. Conclusion: Based on the results, Ochrobactrum oryzae was significantly capable of atrazine biodegradation in the semisalinity aqueous environment

Background: Heavy metals have destructive and irreversible effects on the human, plants and animals. Some industries in Yazd enter industrial wastewater to municipal wastewater collection system. This can lead to high levels of heavy metals in wastewater and in turn in the wastewater treatment plant effluent. Methods: This study was carried out during four months from December 22, 2009 to May 20, 2010. The experiment was performed on the inflow, outlet of anaerobic pond and first and second facultative ponds of wastewater treatment plant and then transferred to the laboratory and measured by atomic absorption spectroscopy. Results: The results of the experiments showed that the average cadmium concentrations in the inflow, anaerobic pond outlet, and first and second facultative pond outlet were 0.0066, 0.0087, 0.0076, and 0.0083μg/l, respectively. The average amounts of chromium in the inflow, anaerobic pond outlet, and first and second facultative pond outlet were 0.0076, 0.0065, 0.0043, and 0.0056 μg/l, respectively. Cadmium concentration in the effluent was higher than standard. Conclusion: The comparison of the obtained data with Iranian standards for wastewater treatment for reuse in irrigation shows that the cadmium concentration exceeded the standard and the chromium concentration was lower than the standard. Therefore, it is not suitable for reuse in the crop farms and aquatic life

Background: Biogas is obtained by anaerobic decomposition of organic wastes buried materials used to produce electricity, heat and biofuels. Biogas is at the second place for power generation after hydropower and in 2000 about 6% of the world power generation was allocated to biogas. Biogas is composed of 40–45 vol% CO2, 55–65 vol% CH4, and about 1% non-methaneVOCs, and non-methane volatile organic compounds. Emission rates are used to evaluate the compliance with landfill gas emission regulations by the United States Environmental Protection Agency (USEPA). BTEX comounds affect the air quality and may be harmful to human health. Benzene, toluene, ethylbenzene and xylene isomers that are generally called BTEX compounds are the most abundant VOCs in biogas. Methods: Sampling of VOCs in biogas vents was operated passively or with Tedlar bags. 20 samples were collected from 40 wells of old and new biogas sites of Shiraz’ landfill. Immediately after sampling, the samples were transferred to the laboratory. Analysis of the samples was performed with GC-MS. Results: The results showed that in the collection of the old and new biogas sites, the highest concentration of VOCs was observed in toluene (0.85ppm) followed by benzene (0.81ppm), ethylbenzene (0.13ppm) and xylene (0.08ppm). Conclusion: The results of the study showed that in all samples, most available compounds in biogas vents were aromatic hydrocarbon compounds.These compounds’ constituents originate from household hazardous waste materials deposited in the landfill or from biological/chemical decomposition processes within the landfill.

Background: Contamination of water with arsenic has attracted the researchers’ attention as a global problem in recent years and has been observed in some parts of Iran. The purpose of this study is to assess the efficiency of welding iron waste in removing arsenic from aqueous solutions. Methods: In this study, the effects of different parameters, such as pH (3-9), initial concentration of arsenic (100-3000 μg/l), contact time (5-90min) and adsorbent dose (2.5-20 g/l), were studied. The final concentrations of arsenic were analyzed by atomic absorption. Results: The results indicated that at pH=3 and fixed dose of 1 g, arsenic removal efficiency of iron waste was 89.73%. By increasing the pH to 7, the removal efficiency increased to 96.44%. Also, an increase in the amount of iron waste from 2.5 to 10g/l, the removal rate increased from about 42.37% to 96.70%. For contact times of 5 and 30 minutes, the removal rate was 9% and 96.62%, respectively. Then, with increasing the contact time to 90 minutes, the removal rate increased to 99.24%. Correlation coefficient of Freundlich and Langmuir isotherms for As(III) was 0.7593 and 0.9979, respectively . Conclusion: The results of the study showed that welding iron waste has a high potential as an effective, fast and cheap method for removal of arsenate and arsenite from aqueous solutions.

Background: Among Alkanes, N-Alkanes with medium chain have been identified as the most important contaminants of the soil. N-hexadecane (C16H34) with low solubility in water also belongs to this group and has been used by many researchers as a model contaminant. The present study aimed to investigate the effect of the external source of carbon (glucose) as co-substrate on removal of hexadecane from the soil.Methods: In this study, a Slurry Sequencing Batch Reactor (SSBR) was used as a pilot by a bacterial consortium, including bacterium Acinetobacter radioresistens, Bacillus subtilis, and Pseudomonas aeruginosa, in order to remove different concentrations of hexadecane (1,4,7, and 10 percent).Sampling was performed four times during the sedimentation step. Then, the samples were analyzed by GC-FID and the results were analyzed statistically.Results: The results showed that hexadecane removal (%) by the microbial consortium was higher in lower initial concentrations in such a way that the biological removal of hexadecane was respectively 45.95%, 38.55%, 34.39%, and 32.40% in the concentrations of 1%, 4%, 7%, and 10% on the third day. Moreover, adding the external carbon source (glucose) on the first day caused a 16% increase in hexadecane removal, which is 1.4 times more than the amount of hexadecane removal in the conditions without co-metabolism.Conclusion: The results showed that SSBR could be used as an exit-situation effective method for hexadecane removal in low concentrations through considering the effective factors in its function, such as dissolved oxygen, pH, and temperature. Also, adding the secondary carbon source could be effective in hexadecane removal from the soil. Yet, this effect might vary on different days.

The need for predictive water quality modeling has arisen largely as a result of increased eutrophication of lakes throughout the world. In 1919 Nauman introduced the concept of oligotrophy and eutrophy, distinguishing oligotorophic lakes with little panktonic algae and eutrophic lakes containing much phytoplankton. The phytoplankton consist of the assemblage of small plants having no or very limited powers of locomotion. A variety of formulations have been developed to represent the effect of temperature, light, and nutrient on phytoplankton growth. A number of processes contribute to the loss rate of phytoplankton. These processes are: respiration, excretion and predatory losses. The zooplankton include animals suspended in water with limited power of locomotion. Phytoplankton as well as zooplankton are usually denser than water, and constantly sink by gravity to lower depths. System dynamics is a method of solving problems by computer simulation. The typical purpose of a system dynamics study is to understand how and why the dynamics of concern are generated and to search for managerial policies to improve the situation. In this paper phytoplankton and zooplankton are simulated by system dynamics approach. Then we integrated a limiting nutrient into our phytoplankton-zooplankton scheme to complete our fundamental picture of how nutrient/food-chain interactions are modeled.

Every natural river has an capacity to assimilate wastes; this is referred to as the river's self purification capacity. DO content is usually an important water quality index. The water quality of a polluted river can be improved either by increasing the river's self purification capacity or by reducing the amount of waste loading the river receivers. Traditional physically based water quality models do not evaluate separately a receiving river's purification ability and the effect of waste loading; thus, these models are not ideal analytical tools for water quality management. This paper introduces and discusses an alternative river water quality modeling approach based on the linear systems theory. Steady-state-system response matrix is a means to summarize the interactions of loadings and responses for linear water quality models. BOD-DO variation in a receiving river has been investigated by following traditional physically based water quality models. A simple physically based river BOD-DO model was derived by Streeter and Phelps (1925) based on their Ohio River water pollution study. The Streeter-Phelps model has been used by sanitary/environmental engineers for many years to evaluate the waste assimilative capacity of a receiving river; it provides a basis on which the treatment requirement for wastewater discharged into the river can be determined. The BOD-DO variation in a time-variable river system with a dispersive effect is traditionally solved by numerical methods. In this study, physical parameterization method is used. Using this method, the system impulse response function of a receiving river can be determined by solving the governing equation of the corresponding physically based model with a Dirac delta function input. This modeling approach is an extension of Green's function techniques that solve a linear differential equation. In a linear systems model, a receiving river's patura-purification capacity is represented completely by the model's impulse response function, whereas the amount of waste loading the river receives is represented by the model's input function. The Enhanced Stream Water Quality Model (QUAL2E) is a comprehensive and versatile stream water quality model. In this paper a river was simulated with QUAL2E. Then a response matrix was built for determination of DO deficiency in any point of river.

Aims: In this study, removal efficiency of linear alkylbenzene sulfonate (LAS) in Stabilization pond plant was investigated. Materials and Methods: In this study, 64 samples were taken for 1-year in stabilization pond plant of Yazd city, central of Iran, in 2010. The samples were analyzed according to the standard methods. Methylene blue active substances were used to determine the amount of anionic surfactants. Results: The most removal efficiency of anionic surfactants occurred in secondary facultative stabilization pond in summer and the least removal efficiency of anionic surfactant in anaerobic stabilization pond in the autumn was obtained. Conclusion: According to the environmental standards for discharge of treated wastewater to the surface water, agricultural water usage and discharge to absorbent wells with P < 0.5 have significant difference values are more than standards.

Aims: In this study, the amount, composition, and energy content of waste in Isfahan, Iran, were examined. Materials and Methods: A time series model was used to predict the amount of waste generation in the future. The past waste changes was the basis for predicting how and to what extent the components will chnage. The energy content of mixed waste was calculated by the common heating value of each component and Dulonge′s formula. Results: The estimation of the amount of waste generated in Isfahan showed that the amount of organic materials would reduce to 59.1% and plastic materials would increase to 24.44%. Heating values of mixed waste, coarse, and fine reject based on dry weight were estimated in the first method as 3230, 1911, and 370 MWh per day, respectively, and as 2656, 1160, and 329 MWh per day, respectively, using Dulong′s formula for the year 2019. Conclusions: The results showed that by separating the combustible part of the waste and incinerating it, a remarkable amount of energy would be produced from waste in Isfahan resulting in the reduction of required landfill space and greenhouse gas emissions.