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Abstract Staphylococcus aureus (S. aureus) is an opportunistic pathogen of the gram-positive variety, known to cause a range of severe infections including cellulitis, pneumonia, osteomyelitis, endocarditis, and sepsis. These infections are associated with significant morbidity and mortality rates in both hospital and community settings. Therefore, it is important to remove S. aureus from the aqueous solution. The present study employed response surface methodology as an effective strategy to optimize the removal of S. aureus through the electro-Fenton (EF), UV/H2O2, and combination EF-UV/H2O2 processes. Under the optimized conditions, the maximum removal efficiency in the EF process of 48.5%, UV/H2O2 process of 36.2%, and combination EF-UV/H2O2 process of 100%. The optimum condition for removal efficiency using combination EF-UV/H2O2 process of 100% was attained at S. aureus concentration of 5 × 106 CFU mL−1, current density of 8.0 mA cm−2, H2O2 dosage of 170 µL L−1, and 2 lamps UV during 7.0 min. Both the production of •OH in the EF and UV/H2O2 process and the additive oxidation effect of UV/H2O2 are the main reasons for the better performance of combination EF-UV/H2O2 process. The results indicate that the EF-UV/H2O2 process is highly promising and environmentally sustainable method for treating wastewater samples contaminated with S. aureus.

Background: Since breast milk is one of the ways of transferring toxic elements from the body, breast milk infection in any form can have adverse effects on the development of the baby. This study aims to investigate the effect of education on knowledge, attitude, and practice of breastfeeding mothers about heavy metals transferred by breast milk. Method: In this interventional study, 100 women referring to Abarkooh health centers were selected and randomly divided into case (n = 50) and control (n = 50) groups. The data collection tool was a questionnaire consisting of four parts, including background questions and knowledge, attitude, and practice. Then, eight two-hour classes were held weekly during two months by food health and safety expert in coordination with the test group. At the end of two months after the last training session, the questionnaires were repeated between the two groups (post-test). Results: The mean score of knowledge, attitude, and practice of the mothers in the intervention group after training significantly increased (P < 0.05), while in the control group no significant difference was observed in the variables before and after the intervention. There was a significant difference between mean of knowledge, attitude, and practice in mothers with demographic variables only between knowledge and education level (P < 0.001). Conclusion: The results showed that breastfeeding training program had a positive effect on promoting the knowledge, attitude, and behavior of the mothers. Therefore, it seems that continuous and varied educational programs are required to prevent the occurrence of heavy metal poisoning caused by breast milk and its consequences in infants.

Abstract The current work investigated the efficacy of the hybrid treatment process of electrocoagulation and adsorption in removing hydroxyzine (HDZ) from polluted aqueous solutions. Response surface methodology (RSM) was used to optimize the operating parameters based on the sub-category of central composite design (CCD). The significance of variables, interactions, and quadratic effects was investigated through analysis of variance (ANOVA). The value of determination coefficient (R 2), Adjusted R 2 (Adj.R 2) and predicted R 2 (Pred.R 2) were 0.9855, 0.9791, and 0.9743, respectively; also, p-value of P

Introduction: Perchloroethylene (PCE) is one of the most well-known chlorinated organic compounds recently detected in aqueous environments. The presence of PCE in aquatic ecosystems has caused many health problems and environmental challenges. Therefore, its removal and treatment from aqueous environments are essential. Materials and Methods: The electro-Fenton (EF) process was carried out in a cylindrical reactor containing 250 mL contaminated water with PCE. The effects of parameters, including solution pH (3-12), current density (2-10 mA cm-2), H2O2 concentration (20-70 µL H2O2 per 250 mL sample.), PCE concentration (5-50 mg L-1), and electrolysis time (1-15 min) on PCE degradation were investigated. The kinetics and radical’s scavenger of the EF process were examined to detect the exact mechanism of PCE degradation. Results: The degradation of the PCE of 98.1% was obtained in the optimum condition, including solution pH of 5, the current density of 8 mA cm-2, H2O2 concentration of 50 µL per 250 mL sample, PCE concentration of 15 mg L-1, and electrolysis time of 10 min. The kinetics studies of the EF process indicated that the obtained results were in satisfactory agreement with the first-order model (R2 = 0.9858, Kapp = 0.2822). Also, the addition of ethanol and tertiary butanol caused an inhibiting effect. Conclusion: The EF process was effectively applied to degrade PCE from polluted water as an efficient technique. The obtained results indicated that the generation of •OH throughout the EF process was the key mechanism that controlled the EF process.

Introduction: Corrosion and scaling are important factors affecting drinking water quality, causing health and economic problems. This study aimed to investigate the indicators of corrosion and scaling in Rafsanjan drinking water. Materials and Methods: The present descriptive cross-sectional study was conducted in winter 2018 and spring 2019 in Rafsanjan. The 56 samples were randomly taken from the drinking water distribution and transmission networks. Physicochemical parameters, such as pH, temperature, total dissolved solids (TDS), total hardness (TH), calcium hardness (CH), electrical conductivity (EC), and alkalinity were measured. Finally, corrosion and scaling indices, including langelier index (LI), ryznar index (RI), aggressiveness index (AI), and Puckorius index (PI) were calculated and analyzed. Results: The mean temperature, pH, CH, TH, TDS, alkalinity, and EC were 17.79 ± 0.80 °C, 8.08 ± 0.11, 56.34 ± 2.72 mg/L.CaCO3, 140.86 ± 6.81 mg/L.CaCO3, 530 ± 110 mg/L, 181.21 ± 13.65 mg/L, and 840 ± 180 µs/cm, respectively. The mean corrosion and scaling indices, including LI = 0.18 ± 0.12, RI = 7.72 ± 0.14, AI = 12.09 ± 0.11, and finally PI = 7.96 ± 0.10 were obtained. Conclusion: Based on the obtained data, drinking water in the transmission and distribution network of Rafsanjan has scaling properties. Water scaling and deposition causes problems, such as blockage of water transmission and distribution pipes, reduction of flow rate and increase of pressure drop in the network, and finally increase of water facilities operation costs. Therefore, measures should be considered to control the scaling of water in this region.

Introduction: Acetamiprid (AP) is one of the most widely used pesticides in the neonicotinoid class. AP residues in the environment have received considerable due to their potential toxicity to humans. Therefore, it is important to remove AP from the aqueous solution. Materials and Methods: In the current study, response surface methodology (RSM) was used as an efficient approach to optimize the removal of AP using the electro-Fenton (EF) process. The effects of the main variables, including reaction time, AP concentration, current density, and H2O2 dosage were investigated and optimized. ANOVA technique was also used to identify the Fisher’s value (F-value) and P-value of the model. Results: The predicted AP removal efficiency by the model was in good agreement with the obtained experimental results with correlation regression of 0.98. The ANOVA test proved that the developed quadratic model was significant with very low P-values less than 0.05, the high F-value of 240.1, and regression coefficients close to 1 at a 95% confidence level. The optimum condition for AP removal efficiency of 99.02% was attained at the reaction time of 12 min, AP concentration of 3.5 mg L-1, the current density of 12 mA cm-2, and H2O2 dosage of 86 µL. Conclusion: RSM was employed as a suitable method to optimize the operating condition and maximize the AP removal. Herein, the EF process as an eco-friendly electrochemical advanced oxidation process (EAOP) successfully applied to remove AP from the water and wastewater.

Malathion (MT) is a widely used organophosphate insecticide with a broad spectrum. MT residues in the environment even at low concentrations can have adverse effects on humans, plants, animals, and ecosystems. In this study aimed to investigate the MT degradation yield from groundwater using persulfate activated magnetic Fe3O4/graphene oxide nanocomposite (PS/Fe3O4-GO MNCs). Thus, the effects of MT concentration, the dosage of PS and Fe3O4-GO MNCs, pH value along with reaction time were investigated and further optimized applying Response Surface Method (RSM). This model equation showed a sufficient match with the measured results from the experimental data with the correlation coefficient (R2) of 0.9819 according to the analysis of variance. For the optimal yield, MT concentration of 3.7 mg/L, PS of 2.25 mM, Fe3O4-GO MNCs dosage of 225 mg/L, reaction time of 22 min and pH of 4 were obtained. Moreover, for MT degradation, the estimated optimal degradation efficiency was 96.5 %. Furthermore, a distinct synergistic effect was observed upon the usage of Fe3O4-GO MNCs for PS activation. The MT degradation rate is generally characterized by a pseudo-first-order kinetic model. Besides, experiments with radical scavengers revealed that both OH∙ and SO4-∙radicals had significant functions in MT degradation yields, with sulphate radicals being the dominant species. Conclusively, results revealed that the PS/Fe3O4-GO MNCs degradation process is an effective method for remediating waters that have been polluted with MT and related pesticides.

Introduction: Since phthalate esters and their derivatives have the potential to disrupt proper endocrine function, these compounds are considered as one of the most important groups of endocrine-disrupting chemicals. The presence of these compounds in various aquatic environments has caused main concerns about human and animal health and causes problems in the environment. Materials and Methods: The treatment process was carried out in a glass reactor containing 200 mL polluted water at room temperature. The Mg-Al layered double hydroxides (Mg-Al-LDH) were successfully synthesized and were applied as adsorbents for the removal of Diethyl Phthalate (DEP) from polluted water. The kinetics and isotherm of the process were investigated to determine the exact mechanism of DEP removal from the water medium. Results: The Mg-Al-LDH was a surface area of 673 (m2 g-1), a total pore of 0.716 (cm3 g-1), and microspore volumes of 0.627 (cm3 g-1), and a pore diameter of 8.64 nm. The maximum DEP removal efficiency of 96.7% was obtained at the DEP concentration of 10 mg L-1, Mg-Al-LDH dosage of 0.50 g L-1, and the reaction time of 30 min. The second-order kinetic model well depicted the kinetics of DEP adsorption (R2 = 0. 99). The Langmuir isotherm model best described the data by predicting the maximum adsorption capacity (qm) of 95.6 mg g-1 and R2 of 0.99. Conclusion: All the results demonstrate that the Mg-Al-LDH is an efficient, safe, and efficient adsorbent in water and wastewater treatment.

Introduction: Endocrine disruptive compounds as a class of organic contaminants in the aquatic environment received severe attention in the last decades. The release of bisphenol A (BPA) as a hazardous organic chemical into the environment has caused high health and environmental concerns. Therefore, its removal from aquatic environments is strongly recommended. The present study deals with BPA removal efficiency from an aqueous environment using the electrocoagulation process (ECP). Materials and Methods: The effects of parameters including BPA concentration (1-10 mg L-1), current density (3-15 mA cm-2), pH (4-10), and reaction time (5-30 min) on the treatment process were investigated. Response surface methodology (RSM) was employed for optimization of the ECP. The significance of the developed model was investigated by the obtained F-value and P-value. Results: The maximum BPA removal of 98.2% was attained at pH of 8.5, BPA concentration of 3.25 mg L-1, the current density of 12.0 mA cm-2, and reaction time of 23 min. The significance of the developed model was confirmed by the high F-value of 46.69 and the very low P-value of < 0.0001. Furthermore, the electrical energy consumption of the process was found to be 0.308 kWh m-3 in the optimum condition. Conclusion: The obtained experimental results revealed that the co-precipitation and the adsorption process through the electrostatic interactions as the main removal mechanisms controlled the treatment process.

Introduction: It has been proposed that dietary intake is associated with multiple sclerosis (MS). The present case-control study was conducted to investigate the relationship between intake of different food groups and occurrence of MS among the recently diagnosed adult patients in Yazd City, Iran. Materials and Methods: In the current study, a group of 45 patients who have recently been diagnosed with MS and 100 healthy controls were investigated in this research. Participants were matched regarding their gender. Dietary intakes were assessed using a self-administered semi-quantitative food frequency questionnaire (FFQ). Participants also completed a demographic questionnaire including information such as age, gender, marital status, job, education, sun exposure, smoking, sunscreen, body mass index (BMI), economic status, as well as their spouseschr('39') occupations and education. Logistic regressions in crude and multivariable-adjusted models were used to investigate the relationship between food groups and the odds of developing MS. Results: The findings showed that participants with high consumption of fruits, potatoes, refined grains, pickles, and fibers had a significantly lower chance for developing MS after adjustment for the maximum possible confounding variables (P < 0.05). Conclusion: The present study revealed that several food groups or nutrients are associated with the development of MS. Further multi-central prospective studies including more participants are needed to confirm these results.

Introduction: Nowadays, water has turned into one of the biggest challenges of the current century, which can be the origin of numerous positive and negative changes across the world. Iran is one of the driest countries with a quarter of the average annual precipitation on a global scale. Thus, the purpose of this study was to investigate the relationship between religious attitudes and tendency towards conserving water in high school students in Zarrin Dasht city, Iran. Materials and Methods: This descriptive cross-sectional study was conducted in 2017. To this end, 800 individuals (400 females and 400 males) were selected using random sampling method by taking into account the proportion of students in each school. To collect the data, two questionnaires of the water conservation tendency inventory containing 12 items and religious attitude questionnaire with 60 items were employed. Then, data analysis was performed using SPSS (version 24) and by running the Chi-square test, Pearson correlation coefficient, as well as descriptive statistics (P = 0.05). Results: The mean scores of religious attitudes and tendency towards conserving water among the participants were equal to 36.18 and 175.83, respectively. Moreover, a significant relationship was found between the students’ religious attitudes, their demographic variables of age and gender, tendency to conserve water, and number of family members (p ˂ 0.05). Moreover, the correlation between religious attitudes and tendency towards saving water was also statistically significant (p ˂ 0.05, r = 0.81). Conclusion: Considering religious attitudes and tendency towards conserving water, religious and moral inputs should be reinforced related to water-saving in students. This can extend their attitudes towards optimal water consumption within the society.

Introduction: It is generally accepted that groundwater is one of the most vital sources of water for drinking use in cities and rural areas. The water drawn from these sources should be sanitary, have low soluble substances, and be free of any pathogens and microorganisms. Materials and Methods: In this study, 90 wells were sampled with proper dispersion over the study area to achieve suitable estimation accuracy. Results: The assessments made based on 10-year averages of water quality in the studied plain showed that according to the Schuler and Wilcox criteria of water quality for drinking and agricultural use, the northern and southern parts of the plain have unsuitable water quality compared to central parts. Interpolation RMSE value of the Inverse Distance Weighting (IDW) model for SO4-, TDS, TH, Mg2+, Cl-, Ca2+ and HCO3- were 8.46, 2615, 246, 6.8, 38.9, 8.3 1.16 also 8.4, 2628, 750.9, 7.0, 39.8, 8.1, 8.1 (mg L-1) for Kriging, respectively. Conclusion: The cause of low groundwater quality in northern regions is the high rate of SO4-, TH, Cl-, and TDS, which are of the most important determinants of water quality for drinking. The examination of samples in the assessment of water quality for agricultural use clearly showed a higher value of EC compared to SAR.

Background and aim: Finding a cost-effective adsorbent can be an obstacle to large-scale applications of adsorption. This study used an efficient activated carbon adsorbent based on agro-waste for dye removal. Methods: Pistachio shells as abundant local agro-wastes were used to prepare activated carbon. Then, it was modified with iron to improve its characteristics. Acid red 14 was used as a model dye in various conditions of adsorption (AR14 concentration 20–150 mg L−1, pH 3–10, adsorbent dosage 0.1–0.3 g L−1, and contact time 5–60 min). Results: A mesoporous adsorbent was prepared from pistachio shells with 811.57 m2 g−1 surface area and 0.654 cm3 g−1 pore volume. Iron modification enhanced the characteristics of activated carbon (surface area by 33.3% and pore volume by 64.1%). Adsorption experiments showed the high effectiveness of iron-modified activated carbon for AR14 removal (>99%, >516 mg g−1). The adsorption followed the pseudo-second kinetic model (k = 0.0005 g mg−1 min−1) and the Freundlich isotherm model (Kf = 152.87, n = 4.61). Besides, the reaction occurred spontaneously (ΔG0 = −36.65 to −41.12 kJ mol−1) and was exothermic (ΔH0 = −41.86 kJ mol−1 and ΔS0 = −3.34 J mol−1 K−1). Conclusion: Iron-modified activated carbon derived from pistachio shells could be cost-effective for the treatment of industrial wastewater containing dyes.

Introduction: The International Standard Organization created a set of specified standards titled ISO 14000 in 1996 which includes numerous advisory documents related to the environment management, environment supervision, environmental performance evaluation, ecologic labeling, life cycle evaluation and environmental aspects. Materials and Methods: This is a descriptive-analytical cross sectional study. The population being studied includes the managers and the staff of Jiroft hospitals. The required data are collected using standard questionnaires of environmental management system from 118 managers and staff in various sections of Jiroft hospitals. Results: The results of the study show that the laboratory, laundry and kitchen condition, water management, contaminants management and spreading to the air, as well as environmental strategies in attaining green hospital standards in Jiroft hospitals, in accordance with ISO 14000, are suitable and at the optimum level. Conclusion: Hospital and health systems can improve their economic and moral situations in the society by helping to attain the goals of the millennium development in the field of health and stability as well as green economic.

Artificial Neural Networks (ANNs) model and Adaptive Neuro-Fuzzy Inference System (ANFIS) were used to estimate and predict the removal efficiency of tetracycline (TC) using the adsorption process from aqueous solutions. The obtained results demonstrated that the optimum condition for removal efficiency of TC were 1.5 g L−1 modified zeolite (MZ), pH of 8.0, initial TC concentration of 10.0 mg L−1, and reaction time of 60 min. Among the different back-propagation algorithms, the Marquardt–Levenberg learning algorithm was selected for ANN Model. The log sigmoid transfer function (log sig) at the hidden layer with ten neurons in the first layer and a linear transfer function were used for prediction of the removal efficiency. Accordingly, a correlation coefficient, mean square error, and absolute error percentage of 0.9331, 0.0017, and 0.56% were obtained for the total dataset, respectively. The results revealed that the ANN has great performance in predicting the removal efficiency of TC. • ANNs used to estimate and predict tetracycline antibiotic removal using the adsorption process from aqueous solutions. • The model's predictive performance evaluated by MSE, MAPE, and R2.

Background: Diazinon is one of the most important pesticides extremely used in agriculture. Since these compounds are resistant to biodegradation, the arrival of these compounds to water resources has become a serious environmental problem. Therefore, in the current work, the removal of diazinon from groundwater was investigated using advanced oxidation processes electro Fenton. Methods: the current work was conducted in lab scale. The effect of operating parameters such as initial concentration of diazinon (1-30 mg.L-1), pH solution(3-9), current density (1-10 mA.cm-2), reaction time (3-30 min), and dosage of H2O2 (20-100 µL.L-1) were investigated. Response surface methodology (RSM) was used to optimize the parameters and suggested model was analyzed using ANOVA. Results: On the optimum condition including initial diazinon concentration of 6.88 mg.L-1, pH solution of 3, the reaction time of 10 min, the current density of 8.18 mA.cm-2, and dosage H2O2 of 83.78 µL.L-1 removal efficiency of diazinon was found to be 98.5 %. Electrical energy consumption (EEC) was found to be 0.524 kWh.m-3. Moreover, the concentration of diazinon in groundwater was found to be 0.934±0.053 µg.L-1. Conclusion: According to the obtained results, electro Fenton process was found to be an efficient technique for successful removal of diazinon and other resistant ungradable organic compound from water sources.

Introduction: Leachate is a liquid coming out of accumulated wet wastes which contains several chemical and dangerous elements. Furthermore, it causes the aquatic ecosystem contamination. The purpose of this study is to give an indication of the effects of Tonekabon landfill on the surface water, so evaluating the amount of leachate polluting in surface waters was investigated. Materials and Methods: In the current study, after 4 sampling periods at 4 stations, parameters of pollutants including BOD5, COD, TSS, TDS, pH, and EC at different stations and in different seasons were investigated and analyzed. Results: The results revealed that there was no significant difference between 4 stations in pH mean values, while values of other parameters were significantly different at different stations. Based on Duncan's test, the station of 3 and 4 were significantly different in the same group, and the stations of 1 and 2 were each in separate groups. On the other hand, an examination of the difference in data mean based on sampling season shows that there is a significant difference between the mean values of pH between summer and spring, while in other parameters there is no significant difference. Conclusion: This landfill is important due to its location in the forest area near the rural and agricultural centers. The results showed that leachate could be transported to farther places in order to prevent soil and aquatic ecosystem Contamination.

Increased urbanization and industrialization have disturbed the balance between water demand and water supply. Thermal power plants are among the largest water consumers and wastewater producers, while wastewater reuse can deal with the both concerns. Effluents of thermal power plants contain various pollutants, so remediation is needed before any other usage. Assessment the efficacy of Reverse Osmosis (RO) system in treatment of Zarand power plant wastewater for reuse was the aim of present work. Physical and chemical parameters including pH, temperature, turbidity, BOD, COD, chromium, sulphate, chloride, nitrate, and phosphate ions were determined in samples collected from three locations of power station: feed water, influent to RO, and effluent. Sampling was done in the first six months of 2012. Data was characterized using descriptive statistics and Excel software. The average performance of RO in the removal percent of turbidity, BOD, COD, chromium, sulphate, chloride, nitrate, and phosphate was 57.5, 14.5, 27.4, 28, 46, 26, 73, and 99% respectively. In spite of less satisfying values of efficiency, mean values of pH, turbidity, BOD, COD, chromium, chloride, nitrate, and phosphate measured in effluent passing through RO were 7.5, 0.14 NTU, 1.8, 2.83, 0.018, 320, 1.6, and 0.001 mg/l respectively, all in compliance with discharging or irrigation standards, while 704 mg/l of sulphate ions detected in effluent, were much higher than acceptable limits.

Release of textile industries waste especially their dying effluent impose a serious pollution on the environment. Reactive dyes are one of the most used dyes which are recalcitrant to conventional treatment processes. In the performed project, the effectiveness of electrocoagulation process was studied on decolorization. RR141 was selected as model dye and treatment process was performed in a simple batch of electrocoagulation (EC) cell using iron electrodes. Central Composite Design (CCD) was used to plan study runs. Experiments were done under 5 levels of various operational parameters at bench scale. Initial concentration of dye was varied among 50 and 500ppm, pH ranging from 4-12; retention time was ranged between 3-30 minutes, 1-3cm was selected as the distance between electrodes, and current intensity studied under the range of 5-30 mA/cm2. EC treatment process of dyestuff wastewater was satisfactory at high levels of current density, pH, and retention time. While increasing the initial dye concentration and electrodes gap had a negative effect on decolorization performance. Determined optimal conditions to treat 200ml of sample were including pH: 9.68, electrode gap: 1.58cm, dye concentration: 180ppm, retention time: 10.82 minutes, and current intensity: 22.76mA/cm2. Successful removal of the model dye about 99.88% was recorded in the mentioned values of variables. Simple design and operation of the experiments can be an interesting option for implementation and applying of inexpensive electrocoagulation treatment process which was successful to reach nearly a complete decolorization.

Background: The presence of heavy metals in the environment especially in water supplies have caused many concerns because of their toxicity and non-degradability. Hexavalent Chromium (Cr) is one of the most toxic metals which is used in many industries, so it is essential to remove it from industrial wastewater. In this study, we made a comparison between different adsorption isotherms in the chromium (VI) removal process using carbon nano tubes from aqueous solutions. Methods: This experimental study used atomic absorption spectrophotometry. To determine the adsorption isotherms, a synthetic sample with defined concentration of Cr (VI) was prepared and different doses of adsorbent were added to it. The effect of initial Cr concentration, pH, adsorbent dose, and reaction time on removal of Cr was investigated. Temperature and mix rate were steady during a defined time. At the end, Cr (VI) concentration measured and adsorbents equality capacities were calculated via formulas and graphs. Data analysis were performed using descriptive statistics. Results: Adsorption capacities (qe) increased with increasing of initial Cr concentration, and reaction time decreased with increasing adsorbent dose and pH. Correlation coefficients for Langmuir, and Freundlich isotherms in oxidized Multi-Walled Carbon Nano Tubes (MWCNTs) were 0.93, 0.874, and 0.714 and in oxidized Single-Walled Carbon Nano Tubes (SWCNTs) were 0.904, 0.868, and 0.711 respectively. Conclusion: Chromium ions adsorption in carbon nano tubes is accordant to Langmuir isotherm model, and MWCNTs have more cc than SWCNTs. Carbon nano tubes are effective adsorbents in removal of Cr (VI) from aqueous solutions.