Sh Gorgani, A Bafkar, Se Fatemi,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: There are major mobile and non-mobile pollution sources due to human activities that can influence aquifers and reduce groundwater quality. Vulnerability assessment is an inexpensive procedure in to identify areas prone to the pollutants. Identification of these sources is essential in water resources management. Mahidasht Plain is one of the important regions of Kermanshah province and plays a significant role in the production of agricultural products. Water supply for agriculture may be at risk due to the indiscriminate withdrawal of groundwater resources of the plains, the recent droughts and potable water requirements. Therefore, analysis and evaluation of the area helps to make better decisions on proper management and control of water pollution.
Materials and Methods: Vulnerability, which is defined as the sensitivity of groundwater quality to pollution load, was applied and determined using intrinsic features of the aquifer. In this study, we have studied inherent vulnerability of the Mahidasht aquifer against pollution by using DRASTIC model and GIS. Seven parameters for the zoning of aquifer vulnerability was used in the DRASTIC method, including depth to the water table, net recharge, aquifer material, soil type, topography, impact of vadose zone and hydraulic conductivity. These parameters were prepared as seven layers of information in Arc GIS10 Software. The data collected for the purpose of this study were taken fromwells log, 44 piezometer in the area, pumping experiments and three rain-gauge stations. The layers prepared in Arc GIS10 software were weighted, ranked and eventually integrated.
Results: The DRASTIC index calculated for the plain ranged from 34 to 120 units. On this basis and according to the standards listed for DRASTIC index, the aquifer was in a vulnerable group with a low or no risk.
Conclusion: DRASTIC model output showed an inherent vulnerability of the aquifer. The model can be used as a primary tool in the development and management of water resources in the future. In addition, this model is not able to produce information about amount and type of pollutants. Therefore, it is recommended to examine the salinity zoning in the future research due to less rainfall and decreasing underground water level and consequently the higher probability of salinity in underground water. Additionally, the domestic and industrial wastewater, sewage irrigation and the fraction used for groundwater recharge should be considered in order to validate the results of Drastic model.
M Kolahkaj, S Battaleblooie, H Amanipoor, S Modabberi,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: Arsenic accumulation in rice has become a major disaster in the recent decade. A number of studies indicated that rice is a major source of arsenic pollution in human diets. This study assessed the arsenic (As) accumulation in rice grain in Meydavood where rice is the main agricultural crop of the region. This research studied the probable presence of arsenic in the rice grains of Maydavood region in Khozestan province and evaluated the arsenic intake through daily rice consumption.
Materials and Methods: Ten rice samples were taken from Meydavood farms during cropping time. Samples were analyzed for arsenic using ICP-MS.
Results: Data were analyzed using SPSS statistical software and then compared with the World Health Organization standards. The mean concentrations of arsenic in rice samples were 0.079 ppm based on dry weight. The results showed that in 30% of the samples, arsenic concentration exceeded the WHO standards. Due to the high concentration of arsenic in rice samples, the arsenic intake by human was calculated using a regimen of safety and considering a consumption rate of 110 g of rice per day and an average body weight of 70 kg.
Conclusion: The total daily intake of As (TDI-iAs) for adults (70 kg body weight and 110 g rice consumption) was in the range of WHO recommended provisional tolerable daily intake value. Since the source of arsenic in Meydavoud is a natural source, thus, comprehensive studies are recommended on its water resources. Additionally, a solution should be found to prevent probable health effects on the residents.
R Nabizadeh Nodehi, Ar Mesdaghinia, S Nasseri, M Hadi, H Soleimani, P Bahmani,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: Water corrosion and scaling are known as destructive phenomenon of drinking water quality and water facilities. In this study, the groundwater tendency to corrosion or scaling in source water, water storage reservoirs and distribution system were studied. Simultaneous use of some qualitative and a quantitative index along with statistical analyses to assess the water scaling or corrosion tendency were investigated.
Materials and Methods: The data analysis of groundwater, water storage reservoirs and water distribution system in rural area of Kurdistan province were analyzed and the amount of Langelier (LI), Ryznar (RY), Pockorius (PSI) and Larson–Skold (LS) and CCPP indices were determined. Corrosion and scaling threshold for qualitative indices were determined based on CCPP index. The mean of indices was compared with the thresholds using independent t-test. ANOVA was used to assess the difference between the indices in different sources of water.
Results: The balance range for LI, RY and PSI found to be -0.1-0.05, 7-9 and 7.1-8.5. The mean CCPP for groundwater, reservoirs and networks were 9.27 ± 1.29, 9.13 ± 1.25, 11.25 ± 1.23, respectively. All three sources of water have some tendencies toward scaling; however, a significant balance status was confirmed statistically. According to Larson–Skold index, sulfate and chloride anions did not play a role in scaling process.
Conclusion: The use of qualitative indices with CCPP index can provide more accurate estimation of water tendency toward scaling or corrosion. The assessment of qualitative indices along with CCPP is recommended in drinking water corrosion monitoring studies.
M Heydari, R Nabizadeh Nodehi, M Ali Mohammadi, K Yaghmaeian,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Bottled water consumption is rapidly increasing in recent years for various reasons.The main aim of this study was to survey the geological origin of Iranian bottled water and determine compliance or lack of compliance with the experimental data obtained through sampling 71 brands of drinking bottled water and mineral water.
Materials and Methods: In this study the coordinates of access points as a georef of the chosen points were launched on the "Iran geological map" and "Iran mineral and warm water map." The compliance of laboratory data and water types with the geological data were evaluated and compared with the important ionic ratios of the extracted water through using awh software.
Results: In examining 71 brands of the bottled water, 28% of the brands did not agree with the laboratory results, reflected by observing higher levels of bicarbonate in 50% of the bottled waters than those of the geological data.. Additionally, 70% of water types were calcic bicarbonate. In the bottled waters from North Alborz range with coastal Time deposits around the Caspian Sea, there was a source of brine or sea water that was about 55% of this amount.
Conclusion: Water pass through different geological structures and the dissolution phenomenon might be an important factor for the observed disagreement. Because chemical treatment and use of additives on mineral waters are not allowed it prompts further studies to determine the cause and origin of this issue through sampling from the factory and water source.
A Moghaddam, M Mokhtari, R Peirovi,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: one of the steps in water treatment to protect microbial quality of water network is disinfection. Chlorine is one of disinfectants. It is necessary to maintain Free Residual Chlorine (FRC) between minimum and maximum throughout the distribution system in accordance to health standards. This study was aimed to optimize Chlorine dosage in water distribution networks using GANetXL model.
Materials and Methods: In this paper for the first time using an add-in called GANetXL optimization that uses a genetic algorithm, the Chlorine injection was optimized in a reference network based on dynamic connection to EPANET2 hydraulic and qualitative analysis in Excel software. The objective function is formulated such that the squared difference between computed chlorine concentrations and the minimum residual concentration at all monitoring nodes at all times is minimum. The decision variables were the optimized injection dose at boosters’ locations.
Results: The injection rate was obtained (minimum: 0, average: 183.87, maximum: 776.57 and total 4412.84 mg/min per a day) at the station as the number of generation was reduced to 200. Critical nodes formed 20% of the total nodes of network.
Conclusion: Based on the results, minimization of Chlorine whilst comply with FRC standard has both health and economical effects. The results can help the water distribution system management in terms of water quality (by maintaining FRC), health promotion and monetary.
M Abadi, Aa Zamani, A Parizanganeh, Y Khosravi, H Badiee,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: Mercury (Hg) contamination in marine ecosystems is a major threat to human health in the developing countries like Iran. The main route of mercury exposure is from consumption of fish and seafood. Upon entering mercury in human bodies, Hg is converted into methyl mercury, which may lead to serious implications including neurological disorders, reproductive abnormalities, kidney failure, emotional instability, gingivitis and tremors. Therefore, research on mercury concentrations in marine ecosystems (water and fishes) can be help to protect human health and reduce the risks of mercury contamination.
Materials and Methods: In this study in order to evaluate the concentrations of Hg in water and fish, water samples (36 stations), fish tissue livers (n=33) and muscles (n=33) of four fish species from the Caspian Sea (southern coasts) were collected and analyzed. For determination of Hg in water and fish samples, Voltammetry and GF-AAS techniques were used, respectively.
Results: The results showed that the average Hg concentration detected in water samples was 1.657 (μg/L) and in fish muscle and liver tissues were 68.636 and 125.606 (μg/g.dw), respectively. The bioaccumulation factor showed that mercury concentrations from water to fish are in the range of 14 to 80 times. The highest levels of mercury in water and fish were observed in the southwest coasts of the Caspian Sea.
Conclusion: According to USEPA and SPPA (China) standards, more than 58 % of the water samples collected from the southern coasts of the Sea was polluted by mercury. However, the average concentrations of mercury in fish samples were less than the standards by WHO and EPA.
Sh Gorgani, A Bafkar, Se Fatemi,
Volume 10, Issue 3 (12-2017)
Abstract
Background and Objective: Rainfall and groundwater level are important parameters of DRASTIC index, thus their time-series were examined using time series analysis for Mahidasht plain vulnerability in Kermanshah Province.
Materials and Methods: DRASTIC model is a quantitative model that seven parameters for transfer of pollution are considered including depth of water table, net recharge, aquifer, soil, topography, unsaturated environment and hydraulic conductivity. The data was prepared in seven-layer information in Arc GIS10 software. After integration, weighting and ranking, DRASTIC index for the region was estimated between 34 and 120. Precipitation is an uncertainty factor in water projects. Precipitation is the origin of other uncertainties such as surface runoff, recharge, and water balance. Underground water level and recharge are main factors in the DRASTIC model that are considered as component hydrological variables and time series, thus, they were analyzed and forecasted using stochastic methods on the horizon in 2032.
Results: Finally, selection of the data predicted in 2032 and the creation of dual new depth to the water table and recharge, as well as the weighting and ranking of the repeated placement in the DRASTIC model, another vulnerabilities map is prepared in which the index DRASTIC was 34 to 110 units.
Conclusion: Results showed that due to further decrease of water table and reduced rainfall, DRASTIC index will be less in the next 18 years (2014-2032).
M Bayatvarkeshi, R Fasihi,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Drought and water shortage in recent years caused rice farmers to use maximum groundwater as a secure source. However, the rice is affected not only by the quantity but also by the quality of water. The purpose of this study was to evaluate trend of quality parameters of groundwater in wet and dry periods in 4 plains including Astaneh, Talesh, Lahijan and Foumanat, which are all located in Gilan province.
Materials and Methods: In this investigation, data was collected for quality parameters from 15 groundwater of the 4 plains of Gilan province from 2003 to 2014. The data was collected from 15 piezometer wells of Astaneh, 41 piezometer wells in Talesh, 24 piezometer wells in Lahijan and 44 piezometer wells in Foumanat. For each well, two time series of 15 quality parameters in wet and dry periods were created in SPSS software. The trend was evaluated by Mann- Kendall test that is a nonparametric method.
Results: The results showed that in both periods, the trend of most quality parameters was declined, However, the quality decline in wet period was more severe. In both periods, the pH and Na % were increasing. Additionally, in dry period, the increasing trend of SAR and SO4 was observed. Overall, the water quality of wells in Talesh plain for cultivation of rice was better than the other plains.
Conclusion: Consumption of groundwater of all the plains in both wet and dry periods for agricultural purposes and especially rice cultivation was without limitation. According to the decreased concentration of the measured parameters during the studied period, it can be expected that groundwater quality of Gilan province plains has been improved.
Z Nejatijahromi, Hr Nassery, M Nakhaei, F Alijani,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Irrigation of agricultural lands with treated wastewater in the main part of the Varamin plain, the highly populated urban areas of the middle part of the plain, and the presence of industries have increased the actual risk of heavy metal contamination of groundwater. Therefore, the concentrations of heavy metals were investigated in this study in order to assess the risk of using groundwater of Varamin aquifer for drinking purposes.
Materials and Methods: A total of 78 groundwater samples were collected to measure the concentrations of Cu, Pb, Zn, Cr, Cd, Fe, Co, and Mn ions. The bivariate correlation analysis has been used to describe the correlation between hydrochemical parameters in the Varamin area. Heavy Metal Evaluation Index (HEI) and Heavy Metal Pollution Index (HPI) of the groundwater were determined to determine the feasibility of drinking supply in Varamin plain.
Results: The average concentrations of cadmium in dry and wet periods were 7.5 and 8 μg/L, respectively. In the wet period, the average concentration of lead in the groundwater of the Varamin plain was 12.5 μg/L. The concentrations of both heavy metals were more than the permissible amount for drinking. Pearson correlation analysis of qualitative data of the water samples of the Varamin plain showed a strong correlation between some heavy metals such as Pb and Co with Cd, Cu and Mn. This reflected a similar source of contamination of the groundwater, inter-correlations, and the same mobility behaviors in the aquifer media. The results obtained from HEI and HPI showed that the pollution of Varamin aquifer in most parts was not dangerous with respect to the heavy metals concentrations, but in some areas, significant variations in the concentrations of some metals can be observed.
Conclusion: It may be expected that the risk of groundwater contamination continues with respect to heavy metals due to the persistence of contamination sources in the Varamin plain. Hence, some measured should be taken with regards to the agricultural recycle water, dispose of domestic and industrial wastewater, and the quality of transferring treated effluent from Tehran to the plain.
H Izanloo, K Solaimani, K Shahedi,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Important information can be obtained about the sources of pollutants in the atmosphere by studying the concentration of heavy metals in atmospheric precipitation.. Therefore, in this study concentrations of Pb, Zn and Cu were measured in samples of urban watershed of Bojnourd in autumn and spring seasons to help urban managers to control pollution in Bojnourd area.
Materials and Methods: This study was a descriptive and cross-sectional research. 24 samples of rain water were collected to measure heavy metals. The amount of heavy metals in the samples was measured using atomic absorption.
Results: Results showed that the pH was alkali in the Bojnourd urban watershed. Concentrations of Pb, Zn and Cu in rainwater in both autumn and spring were compared to international standards of WHO and EPA. The difference was significant (P <0.05) and was less than the standards values. Also, the results of the Pearson correlation test showed that the highest positive correlation was between zinc (r = 0.733) and copper (r = 0.190) in the samples of autumn and spring. This correlation was approved using hierarchical cluster analysis method.
Conclusion: The low levels of pH and low concentrations of heavy metals in comparison with global standards indicated low rainwater pollution to heavy metals. Thus, there is no a health threat to the people of the city. The concentration of heavy metals in the metropolitan area of urban watersheds had been higher than other basin levels and the most dominant contaminant was lead in the residential and commercial areas with the highest urban traffic. The pollution to heavy metals varied in different seasons and the value was higher in spring rainwater samples than the autumn ones.
N Golchinpour, N Rastkari, R Nabizadeh Nodehi, M Abtahi, A Azari, E Iravani, K Yaghmaeian,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Triclosan is one of the substances as anti-microbial that is used in many of these pharmaceutical products. This compound can affect human such as reduction of thyroid hormone levels, antibiotic resistant, and increasing skin cancer. This study evaluated the performance nanophotocatalysis process UV/Xe/TiO2-GO on triclosan removal from aqueous solutions.
Materials and Methods: Synthesis of TiO2@GO and its structure was analyzed by SEM, EDX and FTIR. The effects of pollutant concentration, catalyst dosage, and contact time on the removal of Triclosan were studied by DOE software according to response surface methodology. Analysis of variance test was considered for the influence of parameters. Optimum process condition was determined by desirability factor.
Results: Optimum conditions regarding concentration of pollutant, contact time, and catalyst dosage were determined as 0.205 g/L, 14.898 min, and 0.487 mg/L, respectively. Maximum removal efficiency in optimum condition was 97.542 percent. The catalyst dosage was the most effective parameter in removal of Triclosan.
Conclusion: Using of TiO2@GO and xenon lamp had acceptable efficiency for the removal of Triclosan. The use of Xenon lamps alone was economically affordable.
Ar Mesdaghinia, S Nasseri, M Hadi, E Iravani, M Askari,
Volume 10, Issue 4 (3-2018)
Abstract
Background and Objective: Supply of safe drinking water to each community is one of the most important challenges in improving the general community’s health. Considering the importance of the research on water quality, identification of water quality research gaps was performed by reviewing the relevant studies through a systematic review for Iran.
Materials and Methods: In this study 638, 166, 300 and 1000 relevant articles were found on Scopus, SID, Magiran and Iranmedex databases, respectively. Out of 2104 articles, 1394 articles were excluded from the study. Finally, 710 articles were further reviewed.
Results: Monitoring of pollutants by a descriptive study was the main objective of the most studies (36.62%). Around 13% of the studies were performed on a laboratory scale. Organic pollutants in Iran have been concerned only in 17 provinces, and other provinces have not participated in this regard. Nitrate is studied in around one fifth of the total studies. Heavy metals were also considered as a parameter of concern in the studies carried out on monitoring drinking water resource quality.
Conclusion: This study reflects the research gaps and provides a basis for prioritizing water quality research in Iran. More actions and sound planning should be taken to monitor organic and inorganic pollutants. Chemical and microbial risk assessment, tracing the fate of pollutants and assessment of their ecological effects, investigations on advanced water purification processes, the use of bioremediation methods, identification of biological contaminant using biomarkers and molecular identification techniques are the most important research priorities that require more investigations.
Sm Soleimanpour, Sh Mesbah, B Hedayati,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: Determination of quality parameters of drinkable water is important, especially in developing countries, to increase the productivity and better management and planning of water resources. The aim of current study was to apply CART decision tree data mining technique to determine the most effective factors on drinkable water quality in Kazeroon plain, located west of Fars province, Iran.
Materials and Methods: Qualitative parameters of 60 drinkable wells such as SAR, Na, Cl, SO4, TH, TDS, pH, NO3, CaCO3, HCO3, Ca, Mg, K and EC were taken in the study area. The most effective factors on quality of drinkable water were determined with 90% accuracy, using CART decision tree data mining technique in Clementine 12.0 software.
Results: The results showed that total dissolved solids (TDS) and calcium content (Ca) had the highest impact on quality of drinking water. Therefore, when the TDS of water in this plain is equal or less than 495 mg/L and the calcium content is equal or less than 6.150 meq/L, the water is suitable for drinking.
Conclusion: The TDS and Ca content were the most effective parameters on the quality of drinkable water in this plain, due to its geological formation and the existence of CaCO3 in its structure. The water purification, reduction of soluble material concentration, and monitoring of wells in this plain are recommended.
M Gholamdokht Bandari, P Rezaee, Z Gholamdokht Bandari,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: Water quality assessment is an important step for optimal and proper use of water resources for drinking and selection of suitable and consistent water quality patterns. Therefore, the necessity of studying water quality characteristics in water resource management programs has been highly considered.
Materials and Methods: In this study, the hydrogeochemical quality of groundwater resources in the Siahoo region of Bandar Abbas was studied for drinking, agricultural and industrial purposes. Qualitative parameters of three wells, three springs, one juicy aqueduct and one surface water sample were used as input data. Water quality characteristics and charts were evaluated using Aq.qa and AquaChem software.
Results: Groundwater of the studied area was in the category of very hard water. According to the PIPER chart, the dominant hydrochemical facies were sulfatecolic and chloroformate species. According to the Willcox and Schuller qualitative index, groundwater for agricultural use was moderate and was acceptable for drinking water. In terms of the saturation index of islands, the existing water resources are corrosive to the sediment.
Conclusion: The data of this study indicate that one of the problems of the available water resources in Siahoo region is the high amount of salt and soluble materials, which show the effect of geological formations (evaporation, Chile, carbonates) and salt domes on the groundwater resources and reduction of the quality of water resources.
M Bayatvarkeshi, R Fasihi, H Zareabyaneh,
Volume 11, Issue 1 (6-2018)
Abstract
Background and Objective: Groundwater resources are very important for the survival of living beings. Hence, groundwater modeling has a special importance in water management and planning of each region .In this study, numerically simulation of Hamedan–Bahar aquifer flow path was done by GMS software using geological, hydraulic and hydrologic information.
Materials and Methods: First, a 3D hydrogeological model of the aquifer was prepared and then the aquifer flow was simulated by MODFLOW numerical code. The model was calibrated using a trial and error method. Estimation of groundwater flow path was done with MODPATH numeric code. Finally, the capture area was studied and piezometers and direction of groundwater movement in different time were built.
Results: The results of calibration showed that the difference between observed head and computed head was in allowable range ( 35 m). Estimation of pollution with MODPATH numeric code indicated that in forward moving, the longest way of pollution transport was 43400 m and in backward moveing, the longest way of flow transport was 8270.65 m. The results of the groundwater flow path indicated that the flow transport direction was from southwest to northeast in line with the hydraulic gradient.
Conclusion: It can be concluded that the current trend of groundwater flow will increase aquifer pollution level, which will damage groundwater aquifer.
M Fallah, Ar Pirali Zefrehei, Saa Hedayati,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Due to the vulnerability of water resources, quality control of surface water is one of the key issues in environmental conservation programs. In recent years, Anzali wetland has been exposed to numerous threats, including environmental pollutants. TOPSIS is an efficient and reliable way to assess the quality of water resources.
Materials and Methods: In order to evaluate water quality condition, Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), temperature, pH, turbidity, Total Suspended Solid (TSS), phosphate (PO4-), nitrate (NO3-) and Fecal Coliforms (FC) were measured seasonally from 10 sites of Anzali International Wetland in 2014 and the water quality condition was estimated using TOPSIS method.
Results: The highest BOD5, phosphate, temperature and fecal coliform were measured at station 8. Comparison of TOPSIS values in different sampling stations showed the minimum (0.339) and maximum values (0.689) at the stations 5 and 8, respectively. According to the result, the station 5 (Sorkhankal) had the best water quality condition and station 8 (Pirbazar) had the lowest one. Also, seasonal results of TOPSIS values showed that the maximum value was at spring (0.742).
Conclusion: Discharge of effluents from land uses, agricultural and industrial activities located along the stream, could be considered as important reasons for decreasing water quality. Our results showed that TOPSIS method was clearly able to demonstrate the qualitative changes of water resources, indicating a moderate water quality for Anzali international wetland.
M Teimouri, V Sheikh, A Sadoddin,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Water quality is one of the issues that is of great importance to economic and social development due to the high costs of providing healthy drinking water and its risk to human health and the environment. For instance, although only a short time has passed since the construction of the Shirin-darreh dam, the problems arising from its exploitation have challenged the environmental sector and the health of the water.
Materials and Methods: Water quality is affected by complex processes and various variables. Accordingly, NSFWQI input variables at monthly intervals collected at the dam reservoir during December 2011 - November 2012 was used to evaluate the water quality of the reservoir based on the grey relational analysis process. The results were compared with the results of the NSFWQI method. Also, the Shannon Entropy method was used, considering the importance of weight of variables in different methods.
Results: The results showed that the water quality in the grey analysis method from November 2011 to May 2012 and in the NSFWQI method from October 2011 to April 2012 was moderate and in the remaining months was bad. In the grey analysis method, the highest reservoir value was related to Station 3 and month of February 2012 with a value of 64.2 and the worst water quality was related to Station 4 and month of August 2012 with a value of 39.2. Also, In NSFWQI method, the highest reservoir value was related to station 3 and month of February 2012 with a value of 68.7, and the worst water quality was related to Station 1 and month of August 2012 with a value of 39.1.
Conclusion: Although there was no significant difference between the two methods, due to the greater adaptability of the results of the gray analysis method with the weather events and upstream conditions of the dam, this method is recommended. Due to the relative inadequacy of Shirin-darreh reservoir water in some months, it is essential that the source of pollutants from upstream areas is identified. After identification of the hotspots and preparation of the critical areas map, the appropriate control measures could be implemented.
N Rouniasi, Sm Monavari, Ma Abdoli, M Baghdadi, A Karbasi,
Volume 11, Issue 2 (9-2018)
Abstract
Background and Objective: Water pollution due to heavy metals is a critical and increasing problem worldwide. In this study, removal of cadmium and lead heavy metals using a graphene oxide (GO) adsorbent was examined.
Materials and Methods: GO nanosheets were synthesized through Hummer’s method, and its characterizations were examined using FTIR, XRD, and SEM. The effect of independent variables pH, contact time and initial concentration of the solution on removal efficiency of Cd2+and Pb2+ using response surface methodology was evaluated according to Box-Behnken experimental design. Applying quadratic model, adsorption rate of Cd2+ and Pb2+ achieved 99%. ANOVA was applied for statistical analysis of responses.
Results: According to SEM images, the average size of graphene oxide sheets was 1 to 3 µm. After optimization through RSM, the adsorption capacity for Pb2+ and Cd2+ was 136 mg/g and 68 mg/g, respectively. Examination of the isotherms suggested that Cd2+ and Pb2+ adsorption follows Langmuir and Freundlich isotherm, respectively.
Conclusion: the results show that the graphene oxide performed well in removing both Cd2+ and Pb2+ ions from aqueous solutions. The most influential parameters on the above-mentioned heavy metals adsorption were pH of the solution and the initial concentration.
H Hosseini, A Shakeri, M Rezaei, M Dashti Barmaki, M Shahraki,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Chahnimeh water reservoirs in Sistan and Baluchestan Province are the most important sources for drinking water and irrigation purposes. Many factors such as precipitation, the geography of the watershed, atmosphere, geology and Human activities affect on the chemical, physical, and biological compositions of Chahnimeh water reservoirs. Therefore, the main goal of the present study was to monitor and assess water quality in four Chahnimeh reservoirs during two sampling periods.
Materials and Methods: 84 water samples were taken based on the standard methods (in September 2017 and April 2018) for measurement of the most important physicochemical parameters including major anions, total coliform, BOD, EC, TDS, pH and nitrate. Water quality index (WQI) was used to evaluate the overall water quality status in the Chahnimeh reservoirs.
Results: The results of hydro-geochemical analysis indicated that the water type changed from sodic bicarbonate and sulfur dioxide to radicle chloride during sampling periods. The Gibbs chart showed that weathering of rocks mainly controlled the chemistry of the main water ions. The results of statistical analyses revealed that there was a high correlation between parameters such as chlorophyll, nitrate, sulfate and chlorine with water quality index. Water quality zoning results based on the WQI index indicated a decrease in the water quality of the wells by 3, 2, 1, and 4, respectively.
Conclusion: In this study, the use of WQI was helpful for fast data interpretation for drinking water purposes in the area. Based on the WQI classification, majority of the samples are falling under good to poor water category.
P Firouzi, H Aslani, A Aslhashemi,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Nowadays, swimming pools as a sport and entertainment center have found more popularity. Violation of health based standards in terms of physicochemical, microbial and environmental health indices can turn pools into a potential source of disease transmission and spread. Due to the importance of maintaining swimmers’ comfort, health, and safety, the present study was aimed to consider environmental health status and physicochemical and microbial quality of swimming pools water in Tabriz.
Materials and Methods: In this descriptive cross-sectional study, the official checklists of swimming pools (consisting 10 public and 22 private swimming pools) were obtained from Tabriz Health Center. According to the inspections conducted in February 2017 and August 2017, the related information was extracted from the checklist. Data were analyzed using Excel software, SPSS version 23 and Chi-Square test.
Results: The average accordance of the physicochemical parameters with the standards for public and private pools was 67.5% and 65%, respectively. Among the physicochemical parameters, the residual free chlorine showed less accordance with the standards. On average, in the summer 49.5% and in the winter 28% of the pools showed microbial contamination.
Conclusion: The residual free chlorine values in the pool, Jacuzzi and chiller indicated a weak management of pools and a high potential for pathogenicity. Therefore, continual surveillance of the environmental health status and planning for an objective inspection program by the local authorities, especially in private sector, is suggested.
