reza shokoohi; Hossain Farji; Seyed Amir Ghiasian; Javad Faradmal; Salah Azizi; mahdi salari
Abstract
Background & Objective: Cadmium is considered as one of the most hazardous heavy metals, a non-essential, non-beneficial and highly toxic element to people. In the current study, the ability of aspergillus terreus fungi biomass was surveyed in the removal of cadmium from aquatic solutions. Materials ...
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Background & Objective: Cadmium is considered as one of the most hazardous heavy metals, a non-essential, non-beneficial and highly toxic element to people. In the current study, the ability of aspergillus terreus fungi biomass was surveyed in the removal of cadmium from aquatic solutions. Materials & Methods: This cross-sectional study was carried out in 2015 using fungal biomass culture on a shake flask. The dead biomass of aspergillus terreus fungi was applied as an adsorbent for the treatment of aquatic solution under the conditions of cadmium concentrations: 20, 40, 60, 80, 100 and 120 mg/l, pH: 3, 5, 7 and 9, retention time: 15, 30, 45, 60, 90, and 120 min and adsorbent dose: 0.1, 0.2, 0.5, 1 and 2 g. The remained concentrations of cadmium after adsorption were determined by atomic absorption spectrophotometer. Results: Results indicated that under condition of retention time: 90 min, pH: 7, initial cadmium concentration: 20mg/l and adsorbent dose: 1g, the biomass had a removal efficiency of 94%. Moreover, Adsorption process fitted to Freundlich isotherm with R2=0.9463 and first order kinetic with R2=0.9935. Conclusion: In current study, it was observed that the factors of pH, retention time, dose of aspergillus terreus fungi and initial cadmium concentration had a noticeable effect on the adsorption amount. with regard to the high adsorption capacity of the biomass in comparison to other adsorbents in the removal of cadmium, this biomass can be used as a good adsorbent in wastewater treatment.
behnam sepehrnia; azadeh navidmehr; fazllolah changani
Abstract
Background & Objective: One of the sources of municipal wastes is hospitals and health centers. At present in Iran, details regarding the quantity and quality of wastes generated in health centers are not available and specialists are facing many unknowns in planning, systematic and accurate management ...
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Background & Objective: One of the sources of municipal wastes is hospitals and health centers. At present in Iran, details regarding the quantity and quality of wastes generated in health centers are not available and specialists are facing many unknowns in planning, systematic and accurate management of wastes generated in these centers. Material & Methods: This cross sectional-exploratory and applied study was accomplished in 25 health centers in south of Tehran during 2012-15. In this study, weights and volumes of regular and infectious wastes have been determined in health centers with evaluation of the 250 checklist set during different seasons by environmental health experts. Results: Waste capitation per each person has been determined 41 gr, of which 22.5 gr and 18.6 gr belong to the regular and infectious wastes, respectively. The volume of produced regular and infectious wastes was also 0.07 and 0.056 (L/person/day), correspondingly. The density of the infectious and regular wastes was 329 and 320 (Kg/m3), in that order. Conclusion: The amount of waste generated in health-care centers is much lower than that is able to be a serious challenge for the waste management of these centers regarding the type of their activity, being usually administrative and educational. Appropriate waste separation and not mixing of infectious and regular wastes need to be provided training and greater supervision. The best performance of waste management system in these centers was the safe and accurate disposal of sharp wastes in Safety boxes.
Masoud Yosefi; Faria Hasanzadeh; Adeleh Tabatabei Zadeh; Hamid Reza Naderi; Majid Khadem Rezaiyan
Abstract
Abstract Background and Aim: Nosocomial infections have always been one of the major health problems, and it is becoming increasingly important and a challenge for the health system of different countries. In this study, the contamination in the environment and equipment of two hospitals of Mashhad were ...
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Abstract Background and Aim: Nosocomial infections have always been one of the major health problems, and it is becoming increasingly important and a challenge for the health system of different countries. In this study, the contamination in the environment and equipment of two hospitals of Mashhad were studied. Methods: This cross-sectional study was performed in two academic hospitals. The sampling method was convenient based on policy of infection control committee of each hospital. Environmental samples were collected from water, sink, patient bed and incubators. Samples were cultured in bacterial culture media and phenotypically identified. . Results: Out of 323 samples, 272 (84.2%) were from Qaem Hospital and 51 (15.8%) from Imam Reza Hospital. Overall, 47.1% of samples of Imam Ghaem hospital (128 samples) and 33.3% of samples of Imam Reza hospital (17 samples) were positive (p = 0.071). Overall, the most prevalent organisms were Bacillus (54 samples, 16.7%) followed by Staphylococcus epidermidis (22 samples, 6.8%) and Staphylococcus saprophyticus (16 samples, 0.5%). Others were consisted of Acinetobacter, Enterobacter and pseudomonas spp. Conclusion: Bacillus species have a high persistence in the environment due to Sporulation and their removal will be an indicator of proper environmental health. The presence of potentially pathogenic bacteria in the hospital environment reveals the importance of environmental health control and monitoring programs.
Tahereh Zarei Mahmoudabadi; Behrooz Behnejad; Pirooz Pasdar; Saeed Amooee; Baktash Behnejad
Abstract
Background & objectives: Build wastewater treatment plants alone will not resolve environmental concerns. But, for achieve optimal environmental standards, the performance of the treatment plants must be constantly monitored and evaluated. The purpose of this study was to feasibility of reuse of ...
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Background & objectives: Build wastewater treatment plants alone will not resolve environmental concerns. But, for achieve optimal environmental standards, the performance of the treatment plants must be constantly monitored and evaluated. The purpose of this study was to feasibility of reuse of output effluent wastewater treatment plant of Ardakan. Materials and Methods: This was a descriptive cross-sectional study. During a 6-month period from April 2019 to September 2019, 48 input and output samples were collected. The parameters studied included COD, BOD5, TSS, total coliform and fecal coliform. Which were measured according to the methods outlined in the Standard Method Book for Water and Wastewater Testing. Finally, the results were analyzed by statistical tests. Results: The results showed that, the mean COD, BOD5, TSS, Fecal coliform and Total coliform at the output were 14.36, 4.56, 2.6 mg/L, 41 MPN/100 mL and 11.2 MPN/100 mL, respectively. Also removal efficiency for COD, BOD5 and TSS, total coliform and fecal coliform were 96.27, 96.81, 98.84, 99.99 and 99.99 Percentage, respectively. Conclusions: The results showed that wastewater treatment plant Ardakan resulted in a significant reduction of organic matter and microbial contamination and was in good condition. And complies with standards in the reuse of wastewater for agricultural use, discharge into surface water and discharge to sorbent wells. Document Type: Research article
Seyed Reza Karimi; Nabiollah Mansouri; Lobat Taghavi; Mazaher Moeinaddini
Abstract
Background and Aim: This study aimed to measure heavy metal concentration in the suspended particles which compare it in five different land uses in district 21 of Tehran.Materials and Methods: The procedure was performed based on the ASTM D4096 and EPA standards. The sampling was performed using a high-volume ...
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Background and Aim: This study aimed to measure heavy metal concentration in the suspended particles which compare it in five different land uses in district 21 of Tehran.Materials and Methods: The procedure was performed based on the ASTM D4096 and EPA standards. The sampling was performed using a high-volume pump for 20 minutes. The sampling was done every six days from five stations in district 21 in the spring of 2021. A total of 20 active samples of total airborne particles were collected from the residential, semi-residential, industrial, semi-industrial, and park stations. The airborne particle concentration was analyzed by the gravimetric method, and heavy metals were attached to particles using the ICP-OES. Descriptive tests of SPSS statistical software were used to analyze the data.Results: The results show that the lowest concentration of TSP is in the residential station with 42.34 µg/m3 and the highest concentration is in the industrial station with 253.30 µg/m3. In all applications except the park station, the aluminum has the highest concentration, and the lithium has the lowest concentration. The average concentration of the heavy metals in district 21 is an increasing trend of Al> Cr> Zn> Fe> Mg> Sr> Ti> W> Pb> Li, respectively.Conclusion: The heavy metals in the airborne particles of district 21 have a high concentration and diversity. The factors affecting pollution in the study area include the resources, such as the industries, airports, and light vehicles.
Mahdi Sadeghi; Bay Abotaleb; Naser Bay; Nafiseh Soflaie; Mohammad Hadi Mehdinejad; Morteza Mallah
Abstract
Background & Objective: water, urban, industrial and agricultural centers are usually held near rivers. Surface water sources over other sources of water pollution are more at risk. The goal of this study was to evaluate the quality of the Zaringol River and the impact of agricultural drainage water ...
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Background & Objective: water, urban, industrial and agricultural centers are usually held near rivers. Surface water sources over other sources of water pollution are more at risk. The goal of this study was to evaluate the quality of the Zaringol River and the impact of agricultural drainage water was designed and implemented. Materials & Methods: In regard to agricultural activity around the Zaringol river stations studied and the samples from agricultural drainage water and streams in summer and autumn period specified were taken. NSF WQI index parameters including 9 parameter dissolved oxygen, fecal coliform, pH, BOD, temperature, phosphate, nitrate, turbidity, total dissolved solids, which were measured by using standard methods. Results: The results from the study showed that the index based on NSF WQI for all stations were between 54 to 61. Agricultural water drainage WQI index is between 45-37 that according to the index is poor quality. Conclusion: According to the NSF WQI index indicated that water quality in the river is moderate. But agricultural drainage water quality is bad and affects the quality of river water. Due to the relatively high levels of water quality in the middle class of nutrients, especially nitrates, coliform presence of E.coli that drainage water from agricultural and recreational activities in the upstream station is monitored.
Saeed Dehestaniathar; Shahram Sadeghi; Ebrahim Mohammadi; Esmaeil Ghahramani; Maryam Safay
Abstract
Background and Objectives: Constructed wetlands and conventional treatment methods have a same duty in wastewater treatment، but they have different methods and mechanisms. The aim of this study was to investigate the removal of phenol from synthetic wastewater using horizontal sub-surface flow constructed ...
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Background and Objectives: Constructed wetlands and conventional treatment methods have a same duty in wastewater treatment، but they have different methods and mechanisms. The aim of this study was to investigate the removal of phenol from synthetic wastewater using horizontal sub-surface flow constructed wetland and the aeration and hydraulic retention time effects on phenol removal efficiency. Materials and methods: This study was an interventional study that was carried out on a laboratory scale in horizontal sub-surface flow constructed wetland. In order to determine the effect of aeration on the efficiency of phenol removal,، one reactor was aerated and another one was non-aerated. Pumice was used as a media. The wetlands were planted by Phragmatis australis. Results: The results showed that phenol degradation in both aerated and non-aerated wetland was influenced by organic loading rate and hydraulic retention time. It was also found that the removal of phenol was completely accomplished in both aerated and non-aerated wetlands. This is while the phenol removal rate is higher in aerated wetland,، and in order to achieve the same results,، the hydraulic retention time in non-aerated reactor should be about twice as high as the aerated one. Conclusion: : Horizontal sub-surface flow constructed wetland has a high efficiency in phenol removal. Therefore, if the conditions of operation especially hydraulic retention time are optimized، it can be applied as an effective system for phenol removal from wastewater.
Mohammad Reza Atabaki; Mohammad Sakhaei; Hassan hoveidi; Mohammad Pooteh rigi; Ehsan Karimimanesh
Abstract
Introduction: suspended particles has numerous negative effects on human health and plants.it plays an extremely important role in global climate change as well. Objective:In this survey, variations and influence of meteorological parameters on the concentration of PM10 concentrations were studied. Methods: ...
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Introduction: suspended particles has numerous negative effects on human health and plants.it plays an extremely important role in global climate change as well. Objective:In this survey, variations and influence of meteorological parameters on the concentration of PM10 concentrations were studied. Methods: In this study, first, daily, monthly and seasonal concentrations variation of PM10 were investigated. Then, the degree of correlation between PM10 and meteorological parameters were analyzed by Pearson correlation. Also regression model was used to predict PM10 concentration. Findings: Daily average PM10 concentration during the study period indicates that the highest concentration was in the 22nd August (1077 µg/m3) and the lowest in the 8th march (42 µg/m3). It also shows the monthly average concentration was in August (301/06 µg/m3), While the lowest concentration is accounted November (152/16 µg/m3). Seasonal concentration showed that the highest concentrations are in the summer (272/76 µg/m3). Pearson correlation coefficient analysis shows that particulate matter has a direct correlation with temperature and wind speed, while reverse correlation with precipitation and atmospheric pressure. conclusion: Based on the results of Pearson correlation, it was found that rainfall and relative humidity have adverse effects but the temperature and wind speed have a direct impact on the concentrations of PM10. So that the increased rainfall will reduce the concentration of PM10. While the temperature and the wind speed increases the concentration of suspended particles. Also, the coefficient of determination in the regression model Suggests that 13, 25 and 6 percent of PM10 changes in spring, summer and fall are explained by meteorological parameters used in the model. Based on these results we can say that adverse meteorological conditions may lead to increased concentrations of PM10.
Anis Jahantigh; Hossien Kamani; Elham Norabadi; Edris Bazrafshan; Fateme Sancholi; Ali Meshkinian
Abstract
Abstract Backgroundandpurpose:Chlorophenols are one of the toxic compounds in the industries that are resistant to biodegradation and they last a long time in environment. Therefore, it is necessary to eliminate them and prevent pollution of the receiving waters. The aim of this study was evaluation ...
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Abstract Backgroundandpurpose:Chlorophenols are one of the toxic compounds in the industries that are resistant to biodegradation and they last a long time in environment. Therefore, it is necessary to eliminate them and prevent pollution of the receiving waters. The aim of this study was evaluation of ZnO nano-particles for removal of 2,4,6-trichlorophenol from aqueous solution based on the response surface methodology (RSM) model. Materials and methods: Effect of independent variables including pH, catalyst dose, contact time and the initial concentration of 2,4,6-trichlorophenol on response variable (removal of 2,4,6-trichlorophenolfrom) were evaluated based on the response surface methodology (box-behnken method). In this study, all experiments were carried out in a batch reactor containing ZnO nano-particles under 15 Watt UV lamp Results:The results showed that the best conditions for the removal of 2,4,6-trichlorophenolwere achieved at pH= 3,nano-particle concentration 0.4g/l, reaction time and74.72 min and initial concentration of 2,4,6-trichlorophenol50 mg/l contact time (95.85% removal efficiency). Results: The results showed that the best conditions for removal of 2,4,6-trichlorophenol were achieved at pH=3, nano-particle concentration 0.4g/l, reaction time 74.72 min, initial concentration of 2,4,6-trichlorophenol 50 mg/l (95.85% removal efficiency). Conclusion: The results showed that photocatalytic process was accelerated in the presence of ZnO nano-particle and enhanced removal of 2,4,6-trichlorophenol.
Amin panah; Abdolali Karamshahi; Javad Mirzaei; Mohsen Darabi
Abstract
Background and abjective: Cement factories are considered as one of the most important pollution sources, especially heavy metals pollution. At present, Phytoremediation is known as one of the best strategies to eliminate or reduce these pollutants. In the present study the phytoremediation ability of ...
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Background and abjective: Cement factories are considered as one of the most important pollution sources, especially heavy metals pollution. At present, Phytoremediation is known as one of the best strategies to eliminate or reduce these pollutants. In the present study the phytoremediation ability of Cd, Zn, pb and Mn by nine trees species including Ailanthus glandulosa, Fraxinus rotundifolia, Robinia Pseudo Acasia, Ulmus umbraculifera, Eucalyptus microtheca, Quercus branti, Cupressus arizonica, Pinus eldarica and Cupressus sempervirens were investigated around the Ilam Cement Factory. Material and Methods: For measuring the deposition of metals in the leaves of studied species, 0.2 grams of their biomasses were separately weighed then 4 ml nitric acid (65%) was added to each sample. After 24-hincubation at room temperature, the proportions of considered metals were determined by atomic absorption spectrometry.. The obtainedresults were analyzed by SPSS 20 software usingKolmogrov-Smirnov, Leven and One-way ANOVA Tests. Results: Results showed that the amount of Cd in electro filter of factory was approximately close to the amount of Cd deposited in leaves of considered species, however; the amounts of pb, zn and mn in electro filter of factory were much more than the amounts of these three metals in leaves. The maximum and minimum accumulation of pb were related to Eucalyptus microtheca and Cupressus sempervirens respectively. In addition, the maximum and minimum amounts of deposited Mn were in Ailanthus glandulosa and Pinus eldarica respectively. The results also indicated that the maximum and minimum accumulation of Zn were in Quercus branti and Fraxinus rotundifolia respectively. Conclusion: It can be concluded from the results; the broad-leaf species are much more efficient than narrow-leaf ones in heavy metals remediation, so; it is suggested that in future development plans of green space, the broad-leaf species, especially Quercus branti, Ailanthus glandulosa Desf and Eucalyptus microtheca are more considered.
Hossein Alidadi; Fatemeh Mohammadhosseini; Samaneh Gohari; Ziaeddin Bonyadi
Abstract
Background and Aim: Today, fluorescent lamps are the most common light source in the world and Iran. Mercury in these lamps may enter the environment and cause harmful effects. The aim of the present study was to investigate the effect of heterotrophic wastewater bacteria on the mercury removal from ...
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Background and Aim: Today, fluorescent lamps are the most common light source in the world and Iran. Mercury in these lamps may enter the environment and cause harmful effects. The aim of the present study was to investigate the effect of heterotrophic wastewater bacteria on the mercury removal from fluorescent lamps. Materials and Methods: In this study, different components of lamps were separated using a crushing machine and then mercury was separated from phosphorus powder by acid washing. Bacteria isolated from wastewater were exposed to mercury from acid wash and the mercury content in the lamps was measured by atomic absorption spectrophotometer. The highest concentrations of mercury extracted from lamps was 86.03 ppb in the ratio of 4 HCL: 1 HNO3, and the lowest mercury concentration was14.03 ppb in the 1HCL: 1HNO3 ratio. Results: The results of this study showed that heterotrophic bacteria can reduce mercury levels to less than 5 µg / L. 19 bacteria purified from wastewater were resistant to mercury chloride at concentrations of 5 and 10 mg. Also, 10 bacteria were able to reduce mercury. The highest rate of mercury reduction (92.24%) was related to Pseudomonas marginalis and the lowest rate (62.47%) was related to Pseudomonas simiae. Conclusion: This study showed that heterotrophic sewage bacteria can be used as an efficient, low-cost, and environmentally friendly method for detoxification of mercury from out-of-date fluorescent lamps.
Seyed Amir Hosseini Largani; Shahin Rafiee; Seyed Saeed Mohtasebi
Abstract
AbstractBackground and Aim: The impact of various types of waste produced in the system, transportation and treatment of waste, and diversity of pollutants due to waste collection are some standard problems that communities, including Iran, are straggling with. The city of Tehran, as the capital of Iran, ...
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AbstractBackground and Aim: The impact of various types of waste produced in the system, transportation and treatment of waste, and diversity of pollutants due to waste collection are some standard problems that communities, including Iran, are straggling with. The city of Tehran, as the capital of Iran, produces more than 7,000 tons of waste per day, and if this volume of waste is not properly managed, it will release excessive emissions into the environment.Materials and methods: In this research, a superstructure model for solid waste management was presented, with an approach to achieve the maximum avoided emissions. Optimization was done by normalizing the output of the emissions and then categorizing and sorting the data.Results: We examined 31250 different scenarios and based on the obtained results, the best scenario in terms of emission optimization was scenario 21303. Based on this scenario, organic materials, paper, and wood undergo anaerobic digestion while plastics, glass, and metals enter a recycling system. In this case, the amount of emissions avoided is equal to -837027 kg of carbon dioxide equivalent per day.Conclusion: Anaerobic digestion of organic materials, paper, and wood and recycling of plastics, glass, and iron can be selected as a sustainable model for the current waste management system in Tehran. In this case, the amount of emission avoided will be very high and it can be considered the best environmentally friendly option.Keywords: Superstructure, Optimization, Waste Management, Emissions, Tehran
Mahdi Sadeghi; Kaveh Khosravi; Seyed Mostafa Khezri; Abotaleb Bay
Abstract
Background and objective: Today, with the development, the need for water in the production processes is increasing and so we have sewage with high level of pollution. This study aimed at determining the effectiveness of electrocoagulation for treatment of dairy industry wastewater in a continuous flow ...
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Background and objective: Today, with the development, the need for water in the production processes is increasing and so we have sewage with high level of pollution. This study aimed at determining the effectiveness of electrocoagulation for treatment of dairy industry wastewater in a continuous flow (case study wastewater of Sabah cheese factory Gonbad-e Qabus). Materials & Methods: This study was descriptive and analytical with experimental approach. The samples were collected from Sabah dairy factory and put into the electrocoagulation reactor with continuous flow. At retention times of 20, 40 and 60 minutes with an electric current of voltages 20, 40 and 60 were purged. The samples were carried to the laboratory and various tests of COD, BOD, pH, turbidity, nitrate and phosphate were done. Then the results were compared and analyzed. Results: The mean of COD, BOD, nitrates, phosphorus and turbidity was 4933 ± 231, 600 ± 50, 48.6 ± 14.8, 28 ± 0.7 mg/L and1329 ± 297.6 NTU respectively. The most removal efficiency of these parameters during the study was 84.62, 66.67,55, 54.2 and 85.1 percent respectively. Conclusion:This study showed that electrocoagulation process as a pre-treatment process can remove organic matters, turbidity and nutrients. It can also reduce organic load and increase wastewater biodegradability and it can be an effective option for treating wastewater effectively and thereby preventing pollution in our environment and water resources.
SEYED VAHID RAZAVI TERMEH
Abstract
Background & objective:Cutaneous leech is one of the six major diseases and an example of epidemic diseases in tropical regions. Prevalence and spread of this disease is affected by environmental factors and climatic conditions as well as economic, social and cultural issues. In this research, Analytic ...
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Background & objective:Cutaneous leech is one of the six major diseases and an example of epidemic diseases in tropical regions. Prevalence and spread of this disease is affected by environmental factors and climatic conditions as well as economic, social and cultural issues. In this research, Analytic Hierarchy Process and network analyzes are used to prepare susceptible cutaneous leeches map. Considering high incidence of cutaneous leech in Khuzestan province, Izeh city was selected as a case study. Materials & Methods: For this purpose, the number of patients affected by this disease in Izeh was obtained from the Provincial Health Center from 2009 to 2014. Information layers of elevation, rainfall, temperature, humidity, distance from river, distance from rural areas and land use were identified as effective parameter and their maps were prepared in GIS environment. Parameters were compared in pairs by using AHP and ANP and weight of each factors determining their impacts was calculated in Expert Choice and Super Decision software. Then these parameters were combined based on their obtained weights in ArcGIS software and the final cutaneous leech map was prepared. Evaluation of these methods was performed using relative operation curve (ROC) and 16 points related to leech disease. Result: The results of weighting effective parameters using AHP and ANP showed that the highest weight is related to elevation, temperature and rainfall parameters, respectively. The results of ROC assessment showed that in preparing the map, ANP had an accuracy of 87.8% and AHP had an accuracy of 68.9%. Conclusion:The results of ANP showed that this model had suitable accuracy in preparing susceptible cutaneous leech map and AHP had moderate accuracy in preparing susceptible cutaneous leech map.
Ali akbar Mohammadi; Hossein Alidadi; Mohammad Bagher Delkhosh; Seyede Horriey Fallah; Abdoliman Amouei; Hosseinali Asgharnia; Vahid Taghavi manesh; Monireh Ghorbani
Abstract
Background and purpose: Exposure to the environmental noise originated from traffic is common in urban areas, and can lead to the adverse health effects. Present study aimed to determine average Sound Level Index (SLI) and noise pollution in overcrowded areas of Neyshabur, Iran. Materials and methods: ...
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Background and purpose: Exposure to the environmental noise originated from traffic is common in urban areas, and can lead to the adverse health effects. Present study aimed to determine average Sound Level Index (SLI) and noise pollution in overcrowded areas of Neyshabur, Iran. Materials and methods: This cross-sectional study was accomplished over three primary months of 2015 in Neyshabour city. Six stations in main and crowded parts of Neyshabour including Imam Khomeini, Enghelab Square, Khayyam Square, Azadi Square, Beasat crossroad and Attar Street were applied to measure the SLA in three time period of a day. The measurements were carried out using SVAN953 mean. Statistical analyses of the obtained data were performed by SPSS 18 software. Results: The achieved results revealed that the average SLI at the aforementioned stations were (100.06 ±5.16), (93.38 ± 5.15), (86.58 ± 4.96), (93.38 ± 5.15), (97.38 ± 4.15) and (96.90 ± 2.17) dB respectively. The maximum and minimum Equivalent sound levels were 125.4 and 80.2 dB at the Imam Khomeini station (as a commercial area) in the morning and Beasat station (as a residential area) in the evening correspondingly. Conclusion: In all stations, the measured sound pressure levels were higher than its permission limit for residential and commercial areas. Regarding the adverse health effects of noise pollution, it needs to perform required investigations to reveal the effective factors.
Mahdi Sadeghi; Sarah Jorjani; Ali Shahbazi; Kazem Babaei Ziyarati
Abstract
Background and Aim: Salinity is one of the most important factors affecting growth, photosynthesis and valuable metabolites regarding large scale cultivations. The aim of this research was studying the effect of salinity on growth and pigment composition of Chlorella sp. Collected from paddy-fields of ...
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Background and Aim: Salinity is one of the most important factors affecting growth, photosynthesis and valuable metabolites regarding large scale cultivations. The aim of this research was studying the effect of salinity on growth and pigment composition of Chlorella sp. Collected from paddy-fields of the Golestan Province for evaluating of the potentiality for large scale cultivation. Materials and Methods: Purification was done using N8 culture media at 2 uE.m-2.S-1 irradiance, 280C and continuous illumination at pH 7.2. Salinity treatments were Sodium Chloride at 0, 0.25.0.5 and 1% ( 17 to 170 mM) concentration. Survival and growth were assayed by turbidity, pigment composition as in vivo and in vitro were measured after normalization at the dry weight unit. Results: Results showed that the sharp increase in growth rate viewed at 5th day after inoculation at both control and treatments. Survivality would be keep at this salinity range. The optimum of growth and the highest degree of special growth rate were seen in 0.5% salinity. Difference between the growth at 0.5 and 1 % salinity were significant. The ability of carotenoide production at the 9th day after inoculation were significantly more than the other treatments and insignificant for chlorophyll production. Conclusion: The results show that Chlorella sp., have acclimatized potentiality against this degree of tension and regarding that would be considered as a suitable candidates for future bio fertilizer and soil conditioner inoculation in Golestan province. Document Type: Research ar
Abdolhamid Gohari; Hossein Alidadi; Aamazan Mirzaei
Abstract
Introduction: Swimming pools are one of the most important sport and recreational areas where health tips must be followed, or adverse results would threaten the health of the whole society. Objective: The aim of this study was to identify and evaluate the health and hygienic status of the swimming pools ...
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Introduction: Swimming pools are one of the most important sport and recreational areas where health tips must be followed, or adverse results would threaten the health of the whole society. Objective: The aim of this study was to identify and evaluate the health and hygienic status of the swimming pools as well as water health status in public pools in Mashhad in the first nine months of 2018. Methods: This practical research has been carried out to identify the relevant risks, as field observations for assessing the hygienic condition of indoor areas in 64 swimming pools For data collection in the present study, valid and reliable questionnaires of general information and human resources (14 question), health assessment (37 questions), and water quality control of Mashhad’s swimming pools were used. Parametric analysis of variance was utilized for normal data, and non-normal data were analyzed by Kruskal-Wallis nonparametric test by considering P <0.05. Results: The results of the evaluation of water quality by health centers indicated that the desirability amount of the residual chlorine, water pH, water temperature, water turbidity, microbial thermophile coliforms, heterotrophic bacteria, and water chemical quality was 86%, 96%, 95.44%, 92.44%, 96.49%, 94.96%, and 95.31%, respectively. Amount of the residual chlorine, water turbidity, and heterotrophic bacteria was below the expected level of 95%. The outcomes of the tests administered by Mashhad health and hygiene centers (supervision organization), and pool managers' self-control examinations revealed that the results of water pH, water temperature, thermophile coliform, and water chemical tests were in total accordance with standards (P <0.05). Conclusion: The results showed that most of the health risks were related to the residual chlorine, turbidity, and microbial contamination of water by heterotrophic bacteria. Training swimmers and hygiene culture development have a pivotal role in controlling health risks
Maryam Nikpour; Omid Rahaei
Abstract
Abstract:The interior of airport lounges is often exposed to a lot of noise, which can increase the risk to human health. Due to the dangers of high noise pollution for airport users, the present study was conducted to reduce noise pollution in the transit lounges of Ahvaz International Airport.Background ...
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Abstract:The interior of airport lounges is often exposed to a lot of noise, which can increase the risk to human health. Due to the dangers of high noise pollution for airport users, the present study was conducted to reduce noise pollution in the transit lounges of Ahvaz International Airport.Background and Aim:This study is considered interdisciplinary and applied research and its method is a combination of experimental, simulation and case study methods. firstly, the acoustic status of Ahwaz International Airport was obtained experimentally by measuring the amount of noise pollution during the test period (8 AM to 2 PM) by the Brüel & Kjær sound level meter model 2260 B&K in twelve places. Then the sound absorbing plates were tested with different geometric models. After proving the validity and reliability of the research, the experiments were performed by simulation using EASE 4.4 software.Materials and methods:In this study, the noise level of the airport lounge is considered as a dependent variable and four sound indices including, reverberation time (RT) (main index), indirect sound index (STI), total sound pressure level (SPL) and auditory error coefficient (〖AL〗_CONSE ) were evaluated according to the international standards ISO3382 and ISO 3382-1.Results:After the simulation, it was found that the use of raster pattern sound-absorbing plates (Model A in research) in walls and ceilings with different frequencies has the lowest sound pressure and the above-studied indices are at a desirable level. As a result, Model A has the greatest effect on reducing noise in the tested space.
Gholam Reza Darvishi; Majid Ehteshami; Naser Mehrdadi; Reza Abedini
Abstract
Today, plastics have a special place among the various issues that are considered as sources of pollution. Most of these plastics are in the dimensions of Micro and Nano. One of the most important sources of Microplastics transfer is wastewater treatment plants, where a large amount of these particles, ...
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Today, plastics have a special place among the various issues that are considered as sources of pollution. Most of these plastics are in the dimensions of Micro and Nano. One of the most important sources of Microplastics transfer is wastewater treatment plants, where a large amount of these particles, which are not removed in the treatment process, enter the receiving environment. The purpose of this study is to first determine the optimal method of identifying and extracting particles from wastewater for counting and then to investigate the amount of removal and also to determine the amount of particles leaving the treatment plant.Sampling of inlet and outlet of wastewater treatment plant located in Mazandaran province was done seasonally in three seasons of spring, summer and autumn to determine in which season of the year, the amount of microplastics in wastewater increases or decreases. Also, the extraction and identification method is based on acid washing operation and based on creating a density difference, which has resulted in a favorable result with optimization and innovation.Using this method, the amount of Microparticles and microfibers along with the size and shape of the particle was determined and it was determined to what extent the normal treatment process is able to separate Microplastics from wastewater. The treatment plant can remove an average of 95% of the particles, which means that the remaining 5% of the particles are removed with the effluent and enter the aqueous environment.Finally, it was found that the determined laboratory method can identify and extract Microplastics in very small sizes to a very desirable extent. Also, determining the appropriate parameters of liquid volume, salt consumption and the use of dual capacity iron increased the efficiency compared to other methods and led to the identification of smaller particles than previous research.
Fariborz Bahrami; Aslan Egdernezhad
Abstract
Background and Purpose: Due to the complexities in the nature of ground water systems, it sounds like a demanding job to model either the time or the location of ground water. However, artificial neural networks have a high capability to model both complicated and non-linear models. Besides, Geostatistic ...
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Background and Purpose: Due to the complexities in the nature of ground water systems, it sounds like a demanding job to model either the time or the location of ground water. However, artificial neural networks have a high capability to model both complicated and non-linear models. Besides, Geostatistic Methods are, to a good extent, accurate in modelling ground water.Material and Methods: The aim of this study is to simulate groundwater quality parameters (SAR, TDS and EC) of Dezful Andimeshk plain using ANN-PSO and geostatistical models. For this purpose, information from 61 observation wells in Dezful-Andimeshk plain has been used. Neural network model inputs including qualitative parameters SO42- ، pH ، HCO32-، Na+، Mg2+، Ca2+، TDS، SAR and EC were considered.Results: The results of simulation with intelligent model showed that the highest accuracy of ANN-PSO model in simulation is related to EC, SAR and TDS parameters, respectively. The results of interpolation by geostatistical method showed that the highest accuracy of Kriging model in simulation is related to EC, TDS and SAR parameters, respectively. The general results obtained from the simulation of groundwater quality parameters showed that the ANN-PSO model is more accurate in simulating the groundwater quality parameters of the plain in Andimeshk than the Kriging model. So that the value of R2 for simulating SAR, TDS and EC parameters using ANN-PSO model in the test phase is 0.92, 0.918 and 0.955 respectively and using kriging model is 0.902. 0.915 and 0.931 were estimated.Conclusion: The results of this study also showed that the combination of intelligent models with optimization algorithms is used as a useful tool to simulate groundwater quality parameters.
Mahdi Saghafi; Ali Hajiabdollahi Mamaghani
Abstract
Background and purpose: The objective of this study is to simulate the release of pollutant gases from the chimney of the Tabriz thermal power plant to ascertain the concentration of these pollutants in the vicinity of the power plant. Materials and Methods: The dispersion of pollutants emitted ...
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Background and purpose: The objective of this study is to simulate the release of pollutant gases from the chimney of the Tabriz thermal power plant to ascertain the concentration of these pollutants in the vicinity of the power plant. Materials and Methods: The dispersion of pollutants emitted by the Tabriz thermal power plant is modeled using AERMOD software to analyze the concentrations of sulfur dioxide and nitrogen dioxide in nearby areas and neighboring cities within a 44.85 km square. The data utilized for this modeling encompass one-year meteorological records, emission source particulars, and geographical data. This modeling calculated the distribution pattern of pollution and pollutant concentrations on the ground surface near the Tabriz thermal power plant for intervals of 1, 3, and 24 hours, as well as the annual average. Results: The calculated results reveal that the maximum concentrations of nitrogen dioxide in the studied area, for intervals of 1, 3, and 24 hours, and the annual average are 957, 510, 135, and 5.21 micrograms per cubic meter, respectively. Similarly, the maximum concentrations of sulfur dioxide, for the same intervals, are 3998, 2208, 584, and 22.6 micrograms per cubic meter, respectively. Conclusion: The findings indicate that the maximum concentrations of sulfur dioxide and nitrogen dioxide in certain densely populated residential zones exceed the permissible limits set by environmental standards for specific criteria. Consequently, the health of residents near this power plant could be at risk.
Mohammad Hadi Dehghani; Kamal Azam; Azam Mohammadi
Abstract
Background and objective: the role of swimming pools as a useful and interesting sport is obvious to everyone, which its curable aspect has been considered these days. On the other hand, we should not reject the possible threats of this sport. So, the purpose of this research is to consider the quality ...
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Background and objective: the role of swimming pools as a useful and interesting sport is obvious to everyone, which its curable aspect has been considered these days. On the other hand, we should not reject the possible threats of this sport. So, the purpose of this research is to consider the quality of swimming pools, Whirl pool and cool water basin in Tehran. Methods: in this descriptive- analytic inquiry which has been done in first six months of 1392, in 12, 13, 14 and 15 areas of Tehran municipality and within two parts, studied 27 active lidded swimming pools. At first stage, it has been got samples from all these pools and at the next stage, it has been got renewed samples after presenting suitable ways and instruction to the liable of swimming pools which have been polluted at first stage. All the stages of sampling, transferring to the lab and analyzing of samples from the aspects of remained free color quantity, PH, microbial contamination has done based on standard methods of water and sewer tests. Results: the results show the amount of remained free color at National standard limit of minimum 0 and maximum 4(1-3mg/L) in 48% of samples. 76/1% had standard pH(7.2-8) and also Heterotrophic bacteria of all samples were in a good situation. Conclusion: this study showed the most microbial contamination part was whirl pools and cool water basins in which the amount of remained free color was not on standard extent. Also, in renewed getting samples from pools which were contaminated at first stage of tests, all samples were lack of microbial contamination after considering necessary preparation by liable of swimming pools and giving structures by environmental hygiene inspectors of east hygiene center. Paper Type: Research Article
Ali Asghar Navaei fezabady; Hossein Alidadi; Ali Asghar Najafpoor; Mahmoud Dankoob; Mohsen Yazdani; Masoumeh Saghi; Mohammad Naser Shafiee
Abstract
Background & objective: Evaluation of the effects on environment is an executive view for sustainable development. Solid waste is one of the factors that pollute the environment and the management, control and proper hygiene play a key role in promoting the health of society. So, in establishing ...
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Background & objective: Evaluation of the effects on environment is an executive view for sustainable development. Solid waste is one of the factors that pollute the environment and the management, control and proper hygiene play a key role in promoting the health of society. So, in establishing the composting plants, the environmental issues should be considered and a proper place for these plants must be chosen. This can be one of the most important tasks in waste management programs in developing countries. The aim of this study was to determine the effects of these plants on environment and the procedures to be carried out in this field. Materials & Methods: This research was a review study. By Using the key words (such as compost plants, environmental impact assessment, Iran) the related articles on Web sites google schoolar, iranmedex , SID, Magiran and civilica were searched and studied. Results: In this study, Articles in the period 1995 to 2016 were studied and 40 papers were selected. One paper Environmental impact assessment study methods, One paper method Adkins and Brooke,7 paper method Leopold matrix, one paper matrix math,one paper matrix method of rapid, 2 paper Matrix interactions, the Check list for assessing and one paper matrix type III. Conclusion: In most reviewed studies, the method of Leopold matrix has been used to assess the environmental impact of compost plant. Leopold matrix method has been considered by researchers and experts because of its accuracy, surveying in the construction and operation phases, using two-dimensional tables to express the effects of a compost plant project on the environment, determining suitable place And finally scoring waypoint is placed by specialists for more Compost Plant
Abbas Ali Zamani; Elham Ahmadpour; Abdolhosein Zanganeh; Younes Khosravi
Abstract
Background & objective: Cement manufacturing is the most important and influential industry in the economic prosperity of the country. However, this can be an entrance source for heavy metals to environment. The main objectives of the present study were to identify the spatial variability and main ...
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Background & objective: Cement manufacturing is the most important and influential industry in the economic prosperity of the country. However, this can be an entrance source for heavy metals to environment. The main objectives of the present study were to identify the spatial variability and main sources of heavy metals including Cr, Mn, Ni, Co, Cu, Cd, As and Zn in surface soils of the closed Kurdistan cement factory zone by conducting multivariate geostatistical analysis assisted with ArcGIS 10.2 tool. Multivariate geostatistics was used to survey the spatial distribution of studied heavy metals and their reasons in the studied area. Materials & Methods: In the present study, 88 samples of surface soils were collected in radiuses of 500, 1000, 2000 and 3000 m from the center of the cement factory from two depths of 0–15 and 15-30 cm. Results: According to the gained results, three principal factors were appeared with more than 90% of the total variance through multivariate statistical analysis for heavy metals. For mapping the distribution of the heavy metals amounts, four different models including circular, spherical, exponential and Gaussian with methods of simple Kriging, ordinary Kriging, universal and simple Co-Kriging were identified as the optimum models using ArcGIS 10.2.. The accoracy of the methods were evaluated using coefficient determination, mean absolute error, mean bias error and root mean square error. Conclusion: Heavy metals mapping confirmed that the levels of Cd, As, Pb and Cu in surface soils closed to the factory are higher than global average amount. Also, it can be mentioned that geological structure of the area plays most important role in soil pollution. However, anthropogenic activities, particularly cement plant are considered as another effective factor on soil pollution in the studied area.
Abolfazl Rahmani Sani; Aalieh Tabasi; Mohammad Miri
Abstract
Abstract Background and Aim: Increasing wastewater production and increasing waste production are major threats to human health and the environment; therefore, wastewater treatment and waste reuse should be done. This study aimed to determine the efficiency of plastic, rubber, and electronic wastes for ...
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Abstract Background and Aim: Increasing wastewater production and increasing waste production are major threats to human health and the environment; therefore, wastewater treatment and waste reuse should be done. This study aimed to determine the efficiency of plastic, rubber, and electronic wastes for municipal wastewater treatment by the microbial electrochemical method. Materials and methods: This experimental-practical research was done on a pilot scale. Impacts of time and initial characteristics (temperature, pH, and EC) on the treatment efficiency were investigated. During the research, sampling (twice a week) was done from the input and output of the reactor, and BOD , COD, TSS, pH, and EC parameters were measured according to the standard methods. The results were analyzed by Excel 2010 software. Results: Mean BOD 5 , COD, and TSS in raw sewage were 227, 302, and 274 mg/l. BOD5 removal efficiencies by electronic, rubber, plastic and control wastes were 72.46, 69.74, 60.82, and 62.17%, respectively. Electronic wastes with 55.52% and 79.96% had the highest removal efficiencies of TSS and COD, respectively. Conclusion: Bed material affects BOD 5 removal efficiency. Substrates with electronic wastes and crumb rubber had a higher efficiency in removing BOD 5 , TSS, and COD, which shows the superior characteristics of wastewater treatment by these wastes. Key words: Municipal Wastewater Treatment; Chemical Electro Microbial Process; Electrobacter; Waste