Shayesteh Keivan; Mehran Khojasteh; Niayesh Shayesteh; MohammadJavad Khani; Farzad Zahmati; Vahid Vahid fard
Abstract
Background & objective: Balkhli River, which flows into Yamchi Dam, is the main supplier of drinking water in Ardabil City. This research aims to investigate the effect of the Ghaynarjeh Spring on Balkhli River based on surface waters quality indices.Materials & Methods: First, monthly monitoring ...
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Background & objective: Balkhli River, which flows into Yamchi Dam, is the main supplier of drinking water in Ardabil City. This research aims to investigate the effect of the Ghaynarjeh Spring on Balkhli River based on surface waters quality indices.Materials & Methods: First, monthly monitoring and analysis of Ghaynarjeh spa spring (station 1), river before acceptance and after acceptance of spring water (stations 2 and 3) was done for one year. Despite the low discharge of the spring compared to the river, The concentration of some cations and anions in the river increased greatly. In this article, by determining IRWQISC as the surface water quality index of Iran and NSFWQI as an international index, the water quality for three stations was determined.Results: The results showed that the quality of the river water after entering the spring water was degraded; In other words, the IRWQISC index of the quality of the river's water quality decreased from relatively good to average. Due to the presence of about 2,000 ppb of arsenic, about 7,000 ppb of iron and about 2,500 ppb of manganese in Ghaynarjeh Spring of Nir City, Therefore, the IRWQIST index was also considered in this research. As a result of entering the spring into the river, the river's toxicity index dropped two levels from a relatively good condition to a relatively bad one.Conclusion: Considering the high impact of ghaynarjeh spring on the quality of Balkhli Chai River from the perspective of IRWQISC and especially IRWQIST indicators and considering the importance of Balkhli Chai River in supplying drinking water in Ardabil city, the necessity of purifying the spring water before entering the Balkhli Chai River is quite evident.
Maryam Namdari; Mohammad Reza Atabaki
Abstract
Background and Objectives: Today, sewage sludge disposal methods include drying, burning and application in land, but each of these methods has its own vulnerability. Sewage sludge management is difficult not only because of high levels of production, but also because of high concentrations of heavy ...
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Background and Objectives: Today, sewage sludge disposal methods include drying, burning and application in land, but each of these methods has its own vulnerability. Sewage sludge management is difficult not only because of high levels of production, but also because of high concentrations of heavy metals and pathogens. Research has shown that the transfer of sewage sludge to organic fertilizers, including organic fertilizer, is due to its many advantages, including less heavy metals, easy to use with irrigation systems, faster absorption by plants, and increased their growth efficiency etc. which have been very much considered. The purpose of this study was to investigate the properties of sewage sludge and the liquid fertilizer produced from it.Materials and Methods: In this study, biological sludge was transformed into liquid fertilizer using a 0.25 molar solution. Characterization of biological sludge and liquid fertilizer by conducting heavy metal concentration tests (Zn, Pb, Cd, Cr, Ni, Fe and Cu), total nitrogen, total phosphorus, soluble potassium, total sodium concentration, electrical conductivity and pH was done.Results: The results showed that total nitrogen, soluble potassium, heavy metals concentration decreased with increasing of organic matter extraction from sludge whereas, the amount of phosphorus, total sodium content, electrical conductivity and pH increased.Conclusion: The results of this study showed that the liquid fertilizer produced from sewage sludge due to its characteristics can be used as a soil modifier in agricultural sector.
Samira Abduolrahimi; Ali Akbar Safari Sinegani
Abstract
Background and purpose: Municipal and hospital waste land fills that have various contaminants, especially pharmaceuticals, provide a suitable habitat for resistant bacteria which play a special role in the transfer of resistance genes. Therefore, the abundance of microorganisms and the antibiotic resistance ...
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Background and purpose: Municipal and hospital waste land fills that have various contaminants, especially pharmaceuticals, provide a suitable habitat for resistant bacteria which play a special role in the transfer of resistance genes. Therefore, the abundance of microorganisms and the antibiotic resistance of bacteria in soil and leachate samples of municipal and hospital waste burial sites in Hamedan city were investigated.Materials and methods: The characteristics of soil and leachate as well as the abundance of their microorganisms were tested and counted. Also, the percentage of bacteria resistant to ten commonly used antibiotics ampicillin, amoxicillin, cefixime, gentamicin, streptomycin, tetracycline, doxycycline, chloramphenicol, lincomycin and metronidazole was investigated. In addition, the response of bacteria from two virgin soils and new rubbish landfill to different concentrations of three antibiotics, ampicillin, gentamicin and tetracycline, were measured.Results: The log of population of fungi, actinomycetes, pseudomonas, and enterobacters, was the highest in new rubbish landfill. They were 5.35, 5.28, 6.13, and 5.98 respectively. The percentage of bacteria resistant to all ten antibiotics was higher in samples of new rubbish landfill than in other locations and lower in virgin soil than in other locations. These results were also seen in the dose response of ampicillin, gentamicin and tetracycline antibiotics. The inhibitory concentrations of these antibiotics for new rubbish landfill bacteria were 1500, 1000 and 100 mg/l, respectively. But for virgin soil, they were much less (10, 18 and 50 mg/l respectively).Conclusion: In general, this research showed that municipal and hospital waste landfills provide a suitable habitat for antibiotic-resistant bacteria, which may increase the transfer of resistant genes among soil native bacteria. Therefore, the bacteria that reach the soil through waste can be more harmful.
Hamed Ramezani Awal Riabi; Seyed Alireza Hajiseyed Mirzahosseini; Ali Firoozi Chahak; Ali Reza Mohammad zadeh; Jalil Imani Harsini
Abstract
Background and purpose: Today, polyethylene plastics have become a big problem of environmental health, i.e. excessive production of waste, and it has endangered the environment. But insects have come to the aid of the environment, and in the meantime, the large wax-eating moth (Galleria mellonella) ...
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Background and purpose: Today, polyethylene plastics have become a big problem of environmental health, i.e. excessive production of waste, and it has endangered the environment. But insects have come to the aid of the environment, and in the meantime, the large wax-eating moth (Galleria mellonella) is able to digest polyethylene plastic, polyester, aluminum foil, and even fabric masks with the help of the microbiome of its larva's stomach. This study was also designed to investigate the ability of G. mellonella larvae to remove polyethylene plastic .Materials and methods: First, G. melonella larvae were collected from Gonabad honey apiaries in June 2022. The larvae were reared in the Gonabad University of Medical Sciences medical entomology laboratory with beeswax and synthetic food in plastic boxes and dark rooms (temperature 25±2 oC and humidity 33%). To feed the larvae, pieces of plastic film were cut into diameters (10×10 cm) from the freezer, garbage, and shopping bag (so-called with handles) and placed on ten Petri dishes with a diameter of (8×8 cm) containing ten larvae. Another petri dish (with a hole for larvae to breathe) was placed on the polyethylene films. The produced biomass of larvae related to each type of plastic was analyzed separately with Fourier transform infrared spectrometry (FT-IR).Results: Analysis of 8 types of biomass produced by larvae feeding from wax (control) compared to polyethylene plastics (target item) with FT-IRIt revealed functional groups C-CL, C=O, C=C, R-OH, CH2, -C-C-, which is a sign of polyethylene plastic degradation. Also, the comparison of the amount of plastic removal among the larvae fed on different types of polyethylene film revealed a significant difference (P<0.05).Conclusion: G. melonella larvae as a biological method can be effective in removing plastic from nature in the future.
Maryam Sarkhosh; Ali Asghar Najafpoor; Mona Tabriziazad
Abstract
Treatment of Fresh Leachate From Municipal Solid Waste This study aimed at the examination of the efficiency of roughing filter in nitrate and chemical oxygen demand removal (COD), obtained in the fresh leachate from municipal solid waste landfill. Sampling was done in 3 rates 0.5m/h, 1m/h and 1.5 m/h, ...
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Treatment of Fresh Leachate From Municipal Solid Waste This study aimed at the examination of the efficiency of roughing filter in nitrate and chemical oxygen demand removal (COD), obtained in the fresh leachate from municipal solid waste landfill. Sampling was done in 3 rates 0.5m/h, 1m/h and 1.5 m/h, including simultaneous sampling from input and output filtering, to determine the concentration of nitrate and COD. The average efficiency of COD removal in filtration rates of 0.5 m/h, 1 m/h and 1.5 m/h was equal to 84, 88 and 85 % respectively. The average removal efficiency of nitrate in filtration rates of 0.5 m/h, 1 m/h and 1.5 m/h was equal to 88, 88 and 85 % respectively. Output values of COD and nitrate were lower than the environmental organization standard (p < 0.05). Based on the results of this study, the nitrate removal with a roughing filter was better than that obtained with COD. Keywords: Roughing Filter, Nitrate, Chemical Oxygen Demand,
Nayereh Sadat Hosseini; Soheil Sobhan Ardakani
Abstract
Background and Aim: Road transportation is one of the most important and main sources of metal pollution, which has turned roadside ecosystems into metal sensitive areas. Therefore, this study was conducted to analysis and source identification of Zn, Pb, Cd, Co, Cr, Cu, Mn, and Ni in the surface soils ...
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Background and Aim: Road transportation is one of the most important and main sources of metal pollution, which has turned roadside ecosystems into metal sensitive areas. Therefore, this study was conducted to analysis and source identification of Zn, Pb, Cd, Co, Cr, Cu, Mn, and Ni in the surface soils along some roads in Hamedan Township in 2019.Materials & Methods: In this study, a total of 63 surface soil samples were collected along 700 m from a 9 km section of Goltepe (G), Razan (R) and Kermanshah (K) roads. After preparing soil samples, the contents of elements were determined using ICP-OES. The enrichment contamination severity index (CSI) was also calculated. All statistical analyses of the obtained data were performed using SPSS software.Results: The highest amounts of all the analyzed elements were found in the samples collected from the R site with 122, 0.320, 1.92, 17.3, 334 and 22.2 mg/kg for Zn, Cd, Co, Cr, Mn, and Ni, respectively, and from K site with 26.4 and 25.0 mg/kg for Pb and Cu, respectively, showing the effect of traffic volume. The values of the CSI index showed the acceptable quality of the soil in the studied sites. Also, the results of multivariate statistical analyzes (PCC, PCA and HCA) showed that Mn in roadside soils is probably caused by soil raw materials and exhaust emissions. While the origin of Zn, Pb, Cd, Co, Cr, Cu and Ni emission was mainly from non-exhaust sources (such as wear of brakes, tires, engines and lubricating oil).Conclusion: The findings were indicated the impact of traffic activities on soil contamination with heavy metal in the study areas; therefore, regular and periodic monitoring of soil samples is recommended to control of emission sources of pollutants in order to maintain the health of ecosystems and humans.
Batoul Zarif Gharaati Oftadeh; Najmeh Afsharkohan; Mohammad Zanguoe; Mohammad Rashidi; Reza Barati; Sedigheh Majidian; Ali Akbar Dehghan
Abstract
Background and purpose: The COVID-19 pandemic swiftly swept across the globe as an infectious disease months after its initial reports. This study aims to identify the factors influencing employees’ adherence to health protocols using the health belief model within the Khorasan Razavi Regional ...
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Background and purpose: The COVID-19 pandemic swiftly swept across the globe as an infectious disease months after its initial reports. This study aims to identify the factors influencing employees’ adherence to health protocols using the health belief model within the Khorasan Razavi Regional Water Company context.Materials and Methods:In 2019, a descriptive-analytical (cross-sectional) investigation involved 65 Khorasan Razavi Regional Water Company employees. The data collection process involved a meticulously designed questionnaire fashioned by the researcher. This questionnaire encompassed 11, 24, and 18 inquiries about employees’ knowledge, attitudes, and practices. The responses were collected through an online survey platform, followed by meticulous analysis through the employment of SPSS software.Results: : Examination of the interplay between demographic variables and knowledge, attitudes, and behavior constructs revealed that mean scores for knowledge, attitudes, and behaviors did not display any significant variance amongst gender, educational, or occupational categories (p<0.05). Intriguingly, a significant positive correlation emerged between awareness and attitudes (p<0.01), as well as between awareness and behaviors (p=0.02). Other variables exhibited negligible correlation (p <0.05). Furthermore, the outcomes demonstrated that the structure of awareness significantlyimpacted the studied individuals’ behaviors (p =0.01). Employees’ knowledge and attitudes about coronavirus prevention exhibited a commendable standard.Conclusion: This study underscores the pivotal role of employee knowledge and attitudes in shaping their adherence to COVID-19 prevention practices. Consequently, it is recommended that educational initiatives be introduced as potent tools for augmenting the knowledge and attitudes of Khorasan Razavi Regional Water Company personnel.
Samad Jalilian; Sima Sabzalipour; Ebrahim Rajabzadeh Ghatrami; Amir Hossain Mazarei
Abstract
Background and Purpose: BTEX compounds cause adverse effects on thehealth of employees in various industries, including the oil industry. This studywas conducted with the aim of measuring these compounds and their effecton serum lipid parameters of Abadan oil refinery workers.Materials and Methods: In ...
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Background and Purpose: BTEX compounds cause adverse effects on thehealth of employees in various industries, including the oil industry. This studywas conducted with the aim of measuring these compounds and their effecton serum lipid parameters of Abadan oil refinery workers.Materials and Methods: In this study, 80 workers (40 exposed peoplefrom operational units and 40 non-exposed people from administrativedepartments) were investigated. Sampling and measurement of employees’respiratory area was done using individual sampling pump and measurementof lipid parameters of employees’ blood was done using commercial kits ofPars Azmoun company.Results: The obtained results showed that the average concentration oftoluene, ethylbenzene and xylene compounds in the respiratory area ofthe exposed employees was lower than the standard limit, but the averageconcentration of benzene compound was higher than the recommendedstandard limit. The results obtained from the comparison of blood serum lipidparameters showed that there is no significant difference between the twogroups of exposed and non-exposed employees. The results of Spearman’stest did not find any significant relationship between these parameters anddemographic characteristics in the two groups. However, Pearson’s statisticaltest showed that there is a significant relationship between some blood serumlipid parameters in two groups, and in both groups of employees, the averageblood plasma lipid parameter was higher than the normal range.Conclusion: The results showed that the concentration of benzene compoundis higher than the permissible limit of the standards and the effect ofbenzene on employees should be prevented with adequate engineering andmanagement controls and periodic inspection.
Akram Ghorbani; Mohammad javad Alipoor; Mohammad Ghafoori
Abstract
Background and Purpose: Distribution of heavy metals in all types of sediments is one of the important and new topics in environmental sedimentology. This study was conducted with the aim of investigating the amount of factor pollution, concentration of cadmium and lead metals, geochemical accumulation ...
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Background and Purpose: Distribution of heavy metals in all types of sediments is one of the important and new topics in environmental sedimentology. This study was conducted with the aim of investigating the amount of factor pollution, concentration of cadmium and lead metals, geochemical accumulation index and ecological risk category in the soil downstream of Taibad Landfill.materials and methods: 15 stations were selected at a distance of 100 meters from each other and along the waterway exiting the site from a distance of 100 to 1500 meters. After sampling 5 samples and repeating 3 times from each station, the samples were taken to the laboratory for analysis.Results: In stations 2 and 6, because the pollution factors (CF) are between 1 and 3, the level of pollution in these stations is average, in station 10 it is very high, and for the rest of the stations, because the pollution factors are between 3 and 6, the level of pollution is high. For cadmium metal, the pollution factor (CF) in all stations is between 3 and 6 and the pollution is high. Based on the results, the amount of lead and cadmium metals in the risk category They are ecologically average.Conclusion: The amount of lead metal pollution in station 2 and 6 is moderate, station 3 is very high and in other stations it is high. Cadmium metal contamination was reported in all stations. Both metals are in the medium category in terms of ecological risk.The concentration mentioned metals in the soil downstream of the landfill is significantly higher than the global soil average and the earth's crust. It seems that this pollution is caused by the landfill, which was spread to the downstream lands by seasonal runoff
Adele Abdi; Ozeair Abessi; Ehsan Khavasi
Abstract
Background and Purpose: More than 90% of people’s lives are spent indoorsand indoor air pollution is the cause of more than 2.2 million deaths annuallyworldwide. Contrary to popular belief, the dangers of pollutants in enclosedspaces are greater than in open environments. In this study, the ability ...
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Background and Purpose: More than 90% of people’s lives are spent indoorsand indoor air pollution is the cause of more than 2.2 million deaths annuallyworldwide. Contrary to popular belief, the dangers of pollutants in enclosedspaces are greater than in open environments. In this study, the ability ofthe computer models to simulate flow behavior in the interior space of anindustrial workshop was investigated to may check the satisfaction of theenvironmental standardsMaterials and Methods: The flow pattern and flow mixing and dilution wereinvestigated by developing a specific solver in Open FOAM and comparing theresults with the experimental data.Results: Due to the initial buoyancy, the plume enters from the lower openingwith high concentration and after diluting in indoor space, goes out fromthe roof opening. It is then observed that while there are no openings, theconcentration of Carbon Monoxide in the breathing height of workers willreach the dangerous limit of (100 ppm <) in different models.Conclusion: In this study, the concentration of Carbon Monoxide in thebuilding’s interior space was estimated far higher than the maximum allowablecentration mentioned in the standards. Therefore, the high level of pollutionconcentration in indoor spaces indicates the inadequacy of natural ventilationand the need for mechanical ventilation to could decrease pollution down tothe breathing standard of ocupants.
Ali Toolabi; Fateme Hassanabadi; Elham Ahmadi Beldachi; Nasrin Rezaizad; Ziaeddin Bonyadi
Abstract
Background and Purpose: Nitroaniline is a derivative of aniline known for its high toxicity, potential carcinogenicity, and mutagenic effects. A practical method for removing these compounds from aqueous solutions is applying advanced oxidation processes (AOPs). This study aims to investigate the efficiency ...
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Background and Purpose: Nitroaniline is a derivative of aniline known for its high toxicity, potential carcinogenicity, and mutagenic effects. A practical method for removing these compounds from aqueous solutions is applying advanced oxidation processes (AOPs). This study aims to investigate the efficiency of the activated persulfate process in removing nitroaniline from aqueous solutions under controlled laboratory conditions.Materials and Methods: To conduct this study, the impact of various variables, including pH levels (ranging from 3 to 11), contact time (15 to 120 minutes), nitroaniline concentration (ranging from 1 to 30 mg/L), and persulfate concentration (ranging from 100 to 800 mg/L), on synthetic samples was examined. Post-treatment, the remaining nitroaniline concentration was measured using a UV-vis spectrophotometer at 530 nm. Independent t-tests and descriptive statistics, including mean and standard deviation, were employed to analyze the acquired data.Results: The activated persulfate process with pulsed light achieved the highest nitroaniline removal efficiency at 98.2%. This result was obtained under specific conditions: a contact time of 90 minutes, a pH level of 8, an activated persulfate concentration of 600 mg/L, and a nitroaniline concentration of 1 mg/L. Our findings indicate that the photocatalytic process of persulfate activated by pulsed light adheres to the second-order kinetic model.Conclusion: Based on the outcomes of this study, the persulfate process activated by pulsed light displayed significant effectiveness in removing nitroaniline from aqueous solutions. Therefore, owing to its high removal efficiency, cost-effectiveness, and straightforward management, it is recommended to employ this process to remove organic and resistant pollutants from aqueous solutions.
Akram Ghorbani; Marjan Ziaee; Shabnam Hoshdar Tehrani; Mitra Mohammadi
Abstract
Background and Purpose: 80% of air pollution in urban areas comes fromheavy vehicles. The purpose of this study is to investigate the amount of CO2,CO, HC, NOX pollutants, types of diesel cars and their relationship with the lifeof the car.Materials and Methods: In this study, out of all diesel cars ...
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Background and Purpose: 80% of air pollution in urban areas comes fromheavy vehicles. The purpose of this study is to investigate the amount of CO2,CO, HC, NOX pollutants, types of diesel cars and their relationship with the lifeof the car.Materials and Methods: In this study, out of all diesel cars in Mashhad, whichis 5861 cars, 425 cars were randomly selected and after recording the year ofcar production, using OPTIMA7 NDIR five-gas pollutant device in bright enginemode (Engine operation). Sampling was performed continuously (except forthe first to the fourth of April) in the period of December 6, 2017 to May 9,2017 at nine to twelve and fifteen to twenty o’clock and Then, using SPSSsoftware and statistical tests. The relationship between these pollutants andvehicle life was investigated.Results: According to the amount of sig (p=0/531>0/05) between the life of thecar and carbon monoxide, the amount of sig (p=0/571>0/05) between the lifeof the car and the amount of hydrocarbon, the amount of sig (p=0/153>0/05)between the life of the car and carbon dioxide output and the amount ofp=0/290>0/05 (sig) there is no significant relationship between car life andnitrogen oxides.There is an inverse correlation between the car’s year of manufacture andCO2 and NOX pollutants, So that the higher the car’s year of manufacture,the lower the amount of carbon dioxide and nitrogen oxides. And there is apositive correlation between HC and CO pollutants.Conclusion: The significant level value (sig) between car life and all pollutantsis greater than 0.05, so there is no statistically significant relationship betweencar life and all exhaust gas pollution. Therefore, the amount of air pollution bydiesel cars should be reduced by taking correct management methods.
Pezhman Gheitasian; Seyed Mohammad Tabatabaee jabali; Ahmad Jonidi Jafari; Mohsen Farhadi; Javad Golshani asl; Behzad Valizadeh; Maryam Meserghani
Abstract
Background and Purpose: Tetracycline represents the most prevalent antibiotic group in production and utilization and is extensively employed for the prophylaxis and treatment of infectious diseases in both human and veterinary medicine. The primary objective of this investigation was to assess the efficacy ...
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Background and Purpose: Tetracycline represents the most prevalent antibiotic group in production and utilization and is extensively employed for the prophylaxis and treatment of infectious diseases in both human and veterinary medicine. The primary objective of this investigation was to assess the efficacy of electro-activated persulfate (EC/PS/HR) for eliminating tetracycline from aqueous solutions.Materials and Methods: This study was conducted in a batch mode utilizing an electro-activated persulfate (EC/PS/HR) system. All experiments were carried out under constant temperature conditions. Response surface methodology (RSM) in conjunction with a central composite design (CCD) was employed to optimize the variables associated with the electro-activated persulfate and hydrogen peroxide process, including pH, current density, and the persulfate/hydrogen peroxide molar ratio, with the aim of tetracycline removal. Data analysis in this study was performed using Data Designer 8.0.6 software.Results: The results of this study revealed the use of a quadratic model to predict the impact of independent variables on the efficiency of tetracycline removal in the process. The exceedingly low (p <0.0001) and the high correlation coefficient (R2) of the obtained model signify a robust correlation between experimental and predicted data. The optimal conditions for achieving maximum efficiency in the degradation of tetracycline through electro-activated persulfate were determined to be a pH of 5.6, a persulfate/hydrogen peroxide molar ratio of 1.1, and a current density of 31 mA. Under these conditions, tetracycline degradation reached approximately 95.2%.Conclusion: Based on the findings of this investigation, it can be deduced that the advanced oxidation process relying on electro-activated persulfate (EC/PS/HR) is capable of eliminating contaminants in aqueous environments, influenced by various factors such as hydrogen peroxide dosage, catalyst concentration (persulfate), and pH. The study highlights the capability of the electro-activated persulfate (EC/PS/HR) hybrid process to decompose recalcitrant pollutants like tetracycline from aqueous environments. Overall, the electro-activated persulfate process demonstrates promise for the degradation of tetracycline in aqueous solutions.
Nafiseh Sarabi Mohajer; Maryam Sarkhosh; Ali Asghar Najafpoor; Hossain Alidadi; Sima Baridkazemi
Abstract
Background and Purpose: Consumers often think that food is safe whenstored in refrigerators at 4°C. However, food can still spoil and causefoodborne illness, which is one of the most important health challenges.The present study was conducted with the aim of investigating bacterial andfungal contamination ...
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Background and Purpose: Consumers often think that food is safe whenstored in refrigerators at 4°C. However, food can still spoil and causefoodborne illness, which is one of the most important health challenges.The present study was conducted with the aim of investigating bacterial andfungal contamination in domestic refrigerators.Materials and Methods: In this study, 30 domestic refrigerators wereexamined. First, microbial plates including blood agar and Saburo were placedon the refrigerator shelves for one hour. Then the bacterial cultures wereincubated for 48 hours at 36°C and the fungal cultures were incubated for 5days at 28°C and the colonies were counted. Finally, in order to check the levelof contamination of the refrigerator surfaces, treated samples were preparedfrom the surface of the refrigerator shelves using moist sterile swabs.Results: Based on the results, 100% bacterial contamination and 58% fungalcontamination were observed in the air of household refrigerators, and theamount of bacterial and fungal contamination on the surface of domesticrefrigerators was 4.7-8.9 and 3.6-7.2 (log CFU/cm2) respectivelyConclusion: As seen in this study, bacteria enter food through unwashedhands, raw foods, leaking packaging, unwashed shelves, refrigerator surfaces,and long-term storage of food in the refrigerator. Therefore, if refrigeratorsare not maintained properly, they become a place for the growth ofmicroorganisms and directly and indirectly contaminate the refrigerator andfood and make people sick
Mana Abazari; Habib Allah Tayebi; Khadijeh Aghajani
Abstract
Background and Purpose: the investigation of the adsorption of pollutantsfrom aquatic environments with the least number of experiments, is one ofthe concerns of researchers. In the present study, the aim is to model theadsorption process of acid dye 62 by a metal-organic framework containingaluminum ...
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Background and Purpose: the investigation of the adsorption of pollutantsfrom aquatic environments with the least number of experiments, is one ofthe concerns of researchers. In the present study, the aim is to model theadsorption process of acid dye 62 by a metal-organic framework containingaluminum (MIL-53(Al)-NH2).Materials and Methods: In this study, MIL-53(Al)-NH2 was synthesized fromthe raw material of 2-amino terephthalic acid and aluminum nitrate. Afterexamining the effective parameters on dye adsorption, artificial neuralnetwork (ANN), multiple linear regression (MLR) and multiple nonlinearregression (MNLR) have been used to predict the amount of dye adsorption.Results: The results of XRD, FE-SEM and FTIR analyzes indicated theappropriate synthesis of MIL-53(Al)-NH2. The optimal conditions are: pH=2,time 60 minutes, adsorbent dosage 0.02g and temperature 25°C. Accordingto the results, in the comparison between the three used methods, the neuralnetwork model has the highest prediction accuracy. The output of this modelhas the lowest root mean square error (RMSE) and the highest correlationcoefficient (CC) with true data in comparison with multiple linear and nonlinearregression models.Conclusion: According to the results, it can be seen that the MIL-53(Al)-NH2is an efficient compound and in addition, due to the high efficiency of theartificial neural network model, this model can be used to ensure the resultsof dye removal and reduce costs by reducing the number of experiments.
Fatemeh Sahraei; Ali Shojaei; Zahra Aghababaei; Zahra Hashemi; Mohammad javad Shokoohizadeh; Mahdi Khodabakhshi; Samira Khamutian
Abstract
Background and Purpose: Drinking water the primary source of fluoride essential for bodily requirements. Its appropriate concentration health as a preventive measure against caries. Consequently, this study aims to ascertain the spatiotemporal variations in fluoride concentration within the drinking ...
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Background and Purpose: Drinking water the primary source of fluoride essential for bodily requirements. Its appropriate concentration health as a preventive measure against caries. Consequently, this study aims to ascertain the spatiotemporal variations in fluoride concentration within the drinking water of Hamadan province through the utilization of a Geographic Information System (GIS).Materials and Methods: The present research is a descriptive-analytical investigation conducted across nine cities within Hamadan province in 2019.Data about the fluoride on concentrations in the drinking water of Hamadan province were obtained from the Health Vice-Chancellor of Hamadan University of Medical Sciences. ArcGIS version 10/.8 software was employed to elucidate the spatial and temporal fluctuations in fluoride ion concentration, while SPSS version 16 software was utilized for data. analysis. A significance level of 0.05 was considered across all tests.Results: The study findings revealed that the highest annual fluoride concentration was observed in Kabudarahang city (0.98 ± 0.38 mg/l), whereas the lowest annual average was recorded in Tuyserkan city (0.58 ± 0.35 mg/l). Overall, the mean fluoride concentration in the latter half of the year (0.77 ± 0.42 mg/liter) was slightly higher than in the first half of the year (0.71 ± 0.43 mg/liter). Nevertheless, this discrepancy did not reach statistical significance (p>0.05). Conclusion: The outcomes of this investigation demonstrate that, on the whole, the average fluoride concentration throughout all regions of Hamadan province falls within the optimal range thereby averting potential risks associated with excessive or substandard fluoride levels for consumers.
Mansour Baziar
Abstract
Background and Purpose: Nitrates have long been considered indicative of drinking water quality and a critical concern for human health. The evolution of advanced models for water quality management has spurred decision-makers to incorporate artificial intelligence technologies into water quality planning. ...
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Background and Purpose: Nitrates have long been considered indicative of drinking water quality and a critical concern for human health. The evolution of advanced models for water quality management has spurred decision-makers to incorporate artificial intelligence technologies into water quality planning. This study aims to employ the AdaBoost model, one of the cutting-edge models in water quality management, to predict nitrate concentrations in groundwater using pH and EC (Electrical Conductivity) as input variables.Materials and Methods: Initially, the study analyzed the Pearson correlation matrix and subsequently determined the input variables for multiple AdaBoost models with varying hyperparameters. A sensitivity and dependence analysis of the model's input variables was conducted to assess their impact on nitrate prediction.Results: The results obtained from the AdaBoost model reveal R-squared (R2) values of 0.915 for the training dataset and 0.924 for the test dataset. Additionally, the Mean Squared Error (MSE), Root Mean Squared Error (RMSE), Mean Absolute Error (MAE), and Mean Absolute Percentage Error (MAPE) scores for the training dataset were recorded as 1.02, 1.01, 0.823, and 7.3%, respectively. For the test dataset, these metrics were observed in the order of 0.228, 0.477, 0.375, and 3.2%. The model's sensitivity analysis identified the pH variable as the most influential factor in nitrate prediction.Conclusion: The model analysis demonstrates that the proposed method performs well in predicting nitrate concentrations. This approach holds significant potential for implementation as an intelligent system for forecasting water quality parameters.
Nastaran Aghelan; Soheil Sobhan Ardakani; Mehrdad Cheraghi; Bahareh Lorestani
Abstract
Background and Purpose: Phytoremediation is a new technology forremediation of contaminated soils, this study was conducted to evaluationof efficiency of EDTA, citric acid and salicylic acid chelating agents inphytoremediation enhancing of Amaranthus caudatus and Tagetes patula forelimination of Cr(III) ...
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Background and Purpose: Phytoremediation is a new technology forremediation of contaminated soils, this study was conducted to evaluationof efficiency of EDTA, citric acid and salicylic acid chelating agents inphytoremediation enhancing of Amaranthus caudatus and Tagetes patula forelimination of Cr(III) and Cu(II) from contaminated soils in 2018.Material and Methods: After soil pots contaminating by 50 and 100 (mg/kg)K2Cr2O7 and 200 and 400 (mg/kg) CuSO4 salts, and 2.5 (mmol/kg) of EDTAand citric acid (CA) and 2.0 (mmol/kg) of salicylic acid (SA) solution treating,the cultured seedlings were harvested after 60 days. Then, after seedlingsdigestion, Cr and Cu contents were determined using ICP-OESResults: Based on the results obtained, the maximum contents of Cr (mg/kg) in cultivated soil, root and stem samples of A. caudatus were 2.40, 5.18and 1.86 were found in the SA, EDTA and EDTA treatments, respectively andin T. patula with 2.74, 6.00 and 1.30 were found to be in the SA, EDTA andEDTA treatments, respectively. Also, the maximum contents of Cu (mg/kg)in cultivated soil, root and stem samples of A. caudatus with 6.74, 3.77 and3.34 were found to be in the SA, SA and EDTA treatments, respectively andin T. patula with 6.65, 3.45 and 9.50 were found to be in the SA, EDTA andEDTA treatments, respectively. On the other hand, translocation (TF) andbioconcentration (BCF) factors of A. caudatus both were greater than 1 insoils with 100 mg/kg added K2Cr2O7 containing CA, which indicates that thisspecies can be known as hyperaccumulator of CrConclusion: In conclusion, concerning to the considerable role of organic acidsin soil refining electrokinetic and phytoremediation efficiency enhancing,using of these soil amendment agents is recommended to cleanup ofcontaminated soil with heavy metals
Majid Bonyadi Manesh; Ali Afkham
Abstract
Background and Objective: Oral and dental health is crucial to public health. The primary indices used to assess oral and dental health are DMFT and CPITN indices. This study aimed to evaluate the oral and dental health status of 11 to 13-year-old students in Mashhad City and its relationship with their ...
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Background and Objective: Oral and dental health is crucial to public health. The primary indices used to assess oral and dental health are DMFT and CPITN indices. This study aimed to evaluate the oral and dental health status of 11 to 13-year-old students in Mashhad City and its relationship with their water consumption and other related factors. Materials and Methods: This cross-sectional analytical study was conducted in 2021 on 1,232 students. Sampling was done from all hand-dug wells, semi-deep wells, deep wells, and qanats (underground channels) in the Mashhad region in 2021. All drinking water parameters were measured according to the standards outlined in "Standard Methods for the Examination of Water and Wastewater." Data were analyzed using SPSS software version 20.Result: The mean DMFT index among Mashhad students was 0.98. The average fluoride content in drinking water was 0.38 milligrams per liter(mg/L), lower than the permissible fluoride level in drinking water. According to the relevant statistical tests, there was a significant relationship (p<0.05) between the DMFT index and daily water consumption, fluoride content in drinking water, and daily flossing. Furthermore, a significant relationship (p<0.05) was found between the CPITN index and toothbrush usage. Conclusion: Given the significant association between fluoride content in drinking water and daily flossing with the DMFT index, it is essential to maintain fluoride levels in drinking water within the standard range. Moreover, oral health care practices, such as flossing and toothbrushing, should be taught to students.
Mojtaba Davoudi; Zohre Vojodi; Tayebe Jafarian; Akram Robat jazi; Zainab Fuladi; Maryam Jafarian; Sima Nourbakhsh
Abstract
Background and Purpose: Increased waste production during patient treatment emerges as a serious issue following infectious disease outbreaks. The current study aimed to investigate the effect of the COVID-19 outbreak on medical waste production in Mashhad, Iran.Materials and Methods: In this study, ...
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Background and Purpose: Increased waste production during patient treatment emerges as a serious issue following infectious disease outbreaks. The current study aimed to investigate the effect of the COVID-19 outbreak on medical waste production in Mashhad, Iran.Materials and Methods: In this study, 4 referral (R) and 2 non-referral (NR) hospitals were examined. The quantity and quality of waste produced before (2018-2019) and during COVID-19 (2019-2020) were extracted from hospital records and noted in standard medical waste management checklists. Also, the number of hospital visits due to COVID-19 was determined and entered into the study by referring to the Treatment Deputy of Mashhad University of Medical Sciences.Results: The results showed that the mean waste production was 449.50 ± 49.45 kg/day and 436.04 ± 107.55 kg/day in 2018-2019 (before COVID-19) and 2019-2020 (during the outbreak) in R1, respectively, 3000.26 ± 227.46 kg/day and 3279.72 ± 153.00 in R2, 544.53 ± 107.10 kg/day and 666.32 ± 156.68 in R3, and 476.72 ± 15.96 kg/day and 635.41 ± 54.88 kg/day in R4. Also, the mean waste production was 219.6 ± 36.90 and 199.06 ± 49.58 kg/day in NR1 and 112.1 ± 29.55 kg/day and 108.8±59.1 kg/day in NR2 before and during COVID-19, respectively. Field surveys showed that despite the increased amount of waste production, all waste management stages, such as collection, transfer, and disposal, are being implemented in accordance with the guidelines.Conclusion: The results of this study showed that the medical waste production rate is related to the prevalence of diseases. Considering the importance of medical waste management, it requires careful and correct application of national and international guidelines.
Behnam Pardakti; Hossein Pirkharrati; Farrokh Asad Zadeh
Abstract
Background and Purpose: In this study, heavy metals in the soil around theZanjan city, by using indicators of pollution, carcinogenic and non-carcinogenicrisk and determining the origin by using statistical methods.Materials and Methods: In this study, 30 soil samples were taken from a depthof 0-20 cm ...
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Background and Purpose: In this study, heavy metals in the soil around theZanjan city, by using indicators of pollution, carcinogenic and non-carcinogenicrisk and determining the origin by using statistical methods.Materials and Methods: In this study, 30 soil samples were taken from a depthof 0-20 cm and analyzed based on the method of acid digestion by inductioncoupled plasma spectroscopy.Results: The enrichment factor for zinc and cadmium was in the extremeenrichment category with an average of 42.1 and 34.5, respectively, and theland accumulation index for cadmium was in the high pollution category withan average of 2.8. Spatial changes of the index of pollution load and modifieddegree of pollution showed that the intensity of pollution increased nearthe industrial centers and the linear regression between the ecological riskand the median coefficient of the medium effect range (R2=0.903) showedthat 76% of the samples They are in the possibility of toxicity. Cadmium hadthe highest risk in children and adults with an average non-carcinogenic riskindex of 2 and 0.5, especially exposed to skin absorption with an average of0.5. It shows the risk of more cancer diseases. The result of determining theorigin and contribution of heavy metals with the help of statistical evaluationsshowed that lead, zinc and cadmium are the result of human activities andchromium, copper and arsenic are the result of the combination of human andearth-born activities. have gathered in the areaConclusion: In order to reduce the negative environmental effects of heavymetals in the soil of the study area, measures such as reducing the entry ofpollutants into the soil and refining polluted Soil.
Navid Rafiei; Mohammad Sohani
Abstract
Background and Purpose: In the contemporary context, hazardous waste management has gained prominence within global environmental regulations. However, impediments pose significant challenges to effectively managing such waste. This study aims to identify ten barriers within the hazardous waste management ...
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Background and Purpose: In the contemporary context, hazardous waste management has gained prominence within global environmental regulations. However, impediments pose significant challenges to effectively managing such waste. This study aims to identify ten barriers within the hazardous waste management paradigm, drawing from literature sources and insights from experts in the field.Materials and Methods: The empirical investigation conducted in 2022 solicited the viewpoints of five managers and experts affiliated with a waste management firm in Kermanshah province, Iran. The decision-making techniques of DEMATEL (Decision-Making Trial and Evaluation Laboratory) and interpretive structural modeling were employed to comprehensively comprehend the internal interrelationships and hierarchical structure of these barriers in hazardous waste management.Results: The findings reveal that the primary obstacles, as discerned through the hybrid approach combining decision-making trial and evaluation with interpretive structural modeling, are the lack of public awareness regarding hazardous waste recycling and the absence of comprehensive policies and regulations addressing hazardous waste issues. Notably, the deficiency in public awareness regarding hazardous waste recycling emerges as a causal factor, achieving a score of 0.54. This factor falls within the category of autonomous obstacles, exerting a potent influence with a strength rating of 10 and a relatively weak dependency of 1. Conversely, the inadequacy of policies and regulations addressing hazardous waste is identified as a causal factor with a score of 0.47, belonging to the category of connecting obstacles. It exhibits a robust penetration capability with a rating of 10 and a relatively strong dependency power of 6.Conclusion: The proposed methodology is a valuable tool for policymakers and decision-makers, enabling them to discern the interconnectedness of barriers and their hierarchical arrangement within the hazardous waste management framework.
Abolfazl Naimabadi; Safora Javan; Naghmeh Amin Alslami; Hadi Fazel; Naerh Amini Sani
Abstract
Background and Purpose: COVID-19 can be transmitted directly throughrespiratory droplets or indirectly through devices that transmit infection.SARS-CoV 2 has been identified on various environmental levels in hospitalsand communities.Material and Methods: Sampling was done according to the instructions ...
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Background and Purpose: COVID-19 can be transmitted directly throughrespiratory droplets or indirectly through devices that transmit infection.SARS-CoV 2 has been identified on various environmental levels in hospitalsand communities.Material and Methods: Sampling was done according to the instructions ofthe World Health Organization; environmental samples were taken using aswab with an artificial tip and a plastic shaft. In this study, sampling was doneduring the busy hours of the hospital and the total numbers of samples 48samples were collected and finally the samples were analyzed by polymerasechain reaction-reverse transcription (RT-PCR) method.Results: The results showed that within 36 samples of the hospital, 8 sampleswere positive and in 10 samples of the comprehensive laboratory, two positivesamples were reported. Due to the abnormality of the data, the Kruskal-Wallistest was used to compare datasets of different levels such as (plastic, metal,wood, glass, fibers and living body). According to the results, no significantrelationship was observed between levels with different genders and thedegree of positive tests (P value = 0.341)Conclusion: Contaminated airborne droplets can be displaced by air currentsand deposited on surfaces. Due to the type of surfaces and higher durabilityof these viruses on these surfaces, the need for regular and daily disinfectionbefore and after shifts, and in case of exposure to virus infection, must bedisinfected with appropriate antiviral compounds with the surface. Nocontamination has been observed on other surfaces such as fabrics and fibers,but due to the spread of this virus, necessary precautions should be taken.
Reza Peykanpour Fard; Parvaneh Paykanpour Fard; Hadi Hadian Ghahdarijani
Abstract
Background and Purpose: One of the fundamental problems of air pollution is that it often affects large areas of various land uses, such as cities and agricultural products hundreds of kilometers away from the source of pollutants, or results in cumulative effects with other industries. This research ...
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Background and Purpose: One of the fundamental problems of air pollution is that it often affects large areas of various land uses, such as cities and agricultural products hundreds of kilometers away from the source of pollutants, or results in cumulative effects with other industries. This research aims to quantify the concentration of pollutants in residential areas around industrial areas.Materials and Methods: In this study, the AERMOD software was used for modeling air pollutants. This software uses meteorological data, digital elevation models, and information about pollutant sources. It assesses and quantifies air pollution levels related to PM10, SOX, NOx, and CO pollutants in a specific location.Results: The results of this study indicate that in these 28 population points surrounding the targeted industrial land use, pollutant concentrations in both scenarios with and without background concentrations did not exceed the standard limits for any pollutant. The most significant pollutant in this research was NOx, which showed the slightest difference from the permissible pollution limit. Furthermore, due to the closer proximity of pollutants to environmental standards in this region, increased loading of industrial land uses can lead to various health, economic, and social problems.Conclusion: The findings of this research demonstrate that to assess and quantify pollutant concentrations in the areas surrounding industrial pollutant points, it is advisable to consider background pollution in addition to modeling point sources for greater accuracy in the direction of sustainable development in such areas.
Rahele Valizadeh Ardalan; Mitra Mohammadi; Mohammad Sadegh Bahadori
Abstract
Background and Purpose: Increasing population growth and technological advancements in cities inevitably result in rising noise pollution levels. The emergence of the coronavirus disease worldwide, including Iran, has significantly altered people's daily lives. This has presented a unique opportunity ...
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Background and Purpose: Increasing population growth and technological advancements in cities inevitably result in rising noise pollution levels. The emergence of the coronavirus disease worldwide, including Iran, has significantly altered people's daily lives. This has presented a unique opportunity to assess changes in sound levels. Therefore, this study aims to investigate sound level variations before the outbreak and during the COVID-19 restrictions at a pivotal intersection in Mashhad.Materials and Methods: The initial segment of this study examined the sound equivalent level in April 2018 and 2019 without considering any specific circumstances at the Shohada crossroad. In the second segment, employing SPSS22 software and the Wilcoxon test, we compared the alterations in various sound level indicators before the disease prevalence (April 2018) and during the restrictions (April 2019).Results: The results of the first part of the study revealed that the hourly equivalent sound level (Leq) in April 2018 and 2019 was 70.48 and 70.39 dB, respectively. The results of the second part indicated a significant difference between the two periods under investigation in terms of equivalent sound levels. The maximum and minimum sound equivalent levels (LMax, Lmin) reduction during the disease outbreak compared to the pre-outbreak period was 0.16 and 0.08 dB, respectively. Additionally, during the night curfew hours (21-03) in April 2019, the sound equivalent level decreased by 0.09 dB compared to 2018. Conclusion: The findings of this study demonstrate that the equivalent sound level at the Shohada crossroad in Mashhad exceeded national standards before the disease prevalence. However, noise pollution levels have decreased due to decreased economic activities during the outbreak and the associated restrictions. Nonetheless, the equivalent sound level still surpasses the established standards, indicating that noise pollution at the mentioned intersection persists. Further research is warranted on this subject, encompassing traffic modeling, noise pollution emission inventories, establishing links between land use patterns and noise pollution, and the influence of weather conditions on sound levels.