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Abstract Metals are significant contributors to water pollution, posing serious threats to human health. This study aims to assess the carcinogenic and non-carcinogenic health risks associated with metals in Isfahan drinking water. Eighty water samples were randomly collected from the city's distribution network between January and March 2020–2021. Inductively coupled plasma Optical Emission Spectrometry was used to measure toxic metals, namely Pb, Cr, Cd, Ni, and As concentrations. Results revealed that the mean concentration of Ni (70.03 µg/L) exceeded the WHO reference value (70 µg/L), while the other metals were below the standard values. The average chronic daily intake order of toxic metals was Ni > Cr > Pb > As > Cd. Non-carcinogenic risk assessment through hazard quotient (HQ) and hazard index (HI) demonstrated that both THI for adults (HQingestion + HQdermal = 4.02E−03) and THI for children (HIingestion + HIdermal = 3.83E−03) were below the acceptable limit (less than 1). This indicated no non-carcinogenic risk to residents through water ingestion or dermal exposure. However, findings indicated that the ingestion route was the primary exposure pathway, with HQ values for ingestion exceeding HQ values for dermal adsorption. Carcinogenic risk assessment showed that the risk associated with As metal exceeded the acceptable limit (1 × 10−6). Therefore, implementing treatment improvement programs and appropriate control measures is essential to safeguard the health of Isfahan City residents.

Abstract Regarding the long-term toxic effects of Pb (II) ions on human health and its bioaccumulation property, taking measures for its reduction in the environment is necessary. The MMT-K10 (montmorillonite-k10) nanoclay was characterized by XRD, XRF, BET, FESEM, and FTIR. The effects of pH, initial concentrations, reaction time, and adsorbent dosage were studied. The experimental design study was carried out with RSM-BBD method. Results prediction and optimization were investigated with RSM and artificial neural network (ANN)-genetic algorithm (GA) respectively. The RSM results showed that the experimental data followed the quadratic model with the highest regression coefficient value (R2 = 0.9903) and insignificant lack of fit (0.2426) showing the validity of the Quadratic model. The optimal adsorption conditions were obtained at pH 5.44, adsorbent = 0.98 g/l, concentration of Pb (II) ions = 25 mg/L, and reaction time = 68 min. Similar optimization results were observed by RSM and artificial neural network-genetic algorithm methods. The experimental data revealed that the process followed the Langmuir isotherm and the maximum adsorption capacity was 40.86 mg/g. Besides, the kinetic data indicated that the results fitted with the pseudo-second-order model. Hence, the MMT-K10 nanoclay can be a suitable adsorbent due to having a natural source, simple and inexpensive preparation, and high adsorption capacity.

Abstract 4-Chlorophenol pollution is a significant environmental concern. In this study, powdered activated carbon modified with amine groups is synthesized and investigated its efficiency in removing 4-chlorophenols from aqueous environments. Response surface methodology (RSM) and central composite design (CCD) were used to investigate the effect of different parameters, including pH, contact time, adsorbent dosage, and initial 4-chlorophenol concentration, on 4-chlorophenol removal efficiency. The RSM-CCD approach was implemented in R software to design and analyze the experiments. The statistical analysis of variance (ANOVA) was used to describe the roles of effecting parameters on response. Isotherm and kinetic studies were done with three Langmuir, Freundlich, and Temkin isotherm models and four pseudo-first-order, pseudo-second-order, Elovich, and intraparticle kinetic models in both linear and non-linear forms. The synthesized adsorbent was characterized using X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses. The results showed that the synthesized modified activated carbon had a maximum adsorption capacity of 316.1 mg/g and exhibited high efficiency in removing 4-chlorophenols. The optimal conditions for the highest removal efficiency were an adsorbent dosage of 0.55 g/L, contact time of 35 min, initial concentration of 4-chlorophenol of 110 mg/L, and pH of 3. The thermodynamic study indicated that the adsorption process was exothermic and spontaneous. The synthesized adsorbent also showed excellent reusability even after five successive cycles. These findings demonstrate the potential of modified activated carbon as an effective method for removing 4-chlorophenols from aqueous environments and contributing to developing sustainable and efficient water treatment technologies.

Abstract Wastewaters discharged from different industries and hospitals may contain pharmaceuticals, especially dexamethasone (DEX). Thus, we applied the UV/H2O2 photocatalytic method in the presence of the MgO nanoparticles to remove dexamethasone from synthetic wastewater. Moreover, the effects of parameters such as pH (3–11), hydrogen peroxide concentration (1–8 mM), initial DEX concentration (5–30 mg/L), and catalyst dosage (0.01–0.2 g/L) during the reaction times (0–30 min) were investigated. Furthermore, the efficiency of UV/H2O2 in the presence and absence of catalysts was investigated. The photocatalyst is characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), and Fourier-transform infrared spectroscopy (FTIR) techniques. It was found that the removal rate was enhanced by decreasing pH and the initial dexamethasone concentration. The removal rate was enhanced somewhat with concentrations of hydrogen peroxide and MgO. In the case of UV/H2O2/MgO, 87% removal efficiency was achieved, under the optimal conditions: pH 3, contact time of 30 min, dexamethasone concentration of 20 mg/L, H2O2 of 0.5 mM, and UV radiation of 55 watts. The kinetic data indicated that the reaction followed the second-order kinetic model. The results showed that the UV/H2O2 photochemical process can efficiently remove dexamethasone from aqueous in the presence of a MgO catalyst, and the mineralization efficiency was reached at about 98%.

Abstract An amino-functionalized MIL-68(Al) metal–organic framework (amino-MIL-68(Al) MOF) was synthesized by solvothermal method and then characterized by FESEM, XRD, FTIR, EDX-mapping, and BET-BJH techniques. In order to predict arsenate (As(V)) removal, a robust quadratic model (R2 > 0.99, F-value = 2389.17 and p value 1000 m2/g) and high reusability for As(V)-contaminated water.

Abstract The need for fresh water is more than before by population growth, and industrial development have affected the quality of water supplies, one of the important reason for water contamination is synthetic dyes and their extensive use in industries. Adsorption has been considered as a common methods for dye removal from waters. In this study, Acid Red18 removal in batch mode by using Granular Ferric Hydroxide (GFH) was investigated. The GFH characterized by XRD, FESEM and FTIR analysis. Experiments were designed using RSM-CCD method. The maximum removal efficiency was obtained 78.59% at pH = 5, GFH dosage = 2 g/l, AR18 concentration = 77.5 mg/l and 85 min of contact time. Optimization with RSM and Genetic Algorithm carried out and is similar together. The non-linear adsorption Isotherm and kinetic fitted with Freundlich (R2 = 0.978) and pseudo-second-order (R2 = 0.989) models, respectively. Thermodynamic studies showed that the AR18 adsorption is endothermic process and GFH nature was found spontaneous.

Abstract In the present study, reactive red 198 (RR198) dye removal from aqueous solutions by adsorption using municipal solid waste (MSW) compost ash was investigated in batch mode. SEM, XRF, XRD, and BET/BJH analyses were used to characterize MSW compost ash. CNHS and organic matter content analyses showed a low percentage of carbon and organic matter to be incorporated in MSW compost ash. The design of adsorption experiments was performed by Box–Behnken design (BBD), and process variables were modeled and optimized using Box–Behnken design-response surface methodology (BBD-RSM) and genetic algorithm-artificial neural network (GA-ANN). BBD-RSM approach disclosed that a quadratic polynomial model fitted well to the experimental data (F-value = 94.596 and R2 = 0.9436), and ANN suggested a three-layer model with test-R2 = 0.9832, the structure of 4-8-1, and learning algorithm type of Levenberg–Marquardt backpropagation. The same optimization results were suggested by BBD-RSM and GA-ANN approaches so that the optimum conditions for RR198 absorption was observed at pH = 3, operating time = 80 min, RR198 = 20 mg L−1 and MSW compost ash dosage = 2 g L−1. The adsorption behavior was appropriately described by Freundlich isotherm, pseudo-second-order kinetic model. Further, the data were found to be better described with the nonlinear when compared to the linear form of these equations. Also, the thermodynamic study revealed the spontaneous and exothermic nature of the adsorption process. In relation to the reuse, a 12.1% reduction in the adsorption efficiency was seen after five successive cycles. The present study showed that MSW compost ash as an economical, reusable, and efficient adsorbent would be desirable for application in the adsorption process to dye wastewater treatment, and both BBD-RSM and GA-ANN approaches are highly potential methods in adsorption modeling and optimization study of the adsorption process. The present work also provides preliminary information, which is helpful for developing the adsorption process on an industrial scale.

Abstract In the present study, the adsorptive removal of organophosphate diazinon pesticide using porous pumice adsorbent was experimentally investigated in a batch system, modelled and optimized upon response surface methodology (RSM) and artificial neural network-genetic algorithm (ANN-GA), fitted to isotherm, kinetic and thermodynamic models. The quantification of adsorbent elements was determined using EDX. XRD analysis was utilized to study the crystalline properties of adsorbent. The FT-IR spectra were taken from adsorbent before and after adsorption to study the presence and changes in functional groups. The constituted composition of the adsorbent was determined by XRF. Also, the ionic strength and adsorbent reusability were explored. The influences of operational parameters like pH, initial pesticide concentration, adsorbent dosage and contact time were investigated systematically. ANN-GA and RSM techniques were used to identify the optimal process variables that result in the highest removal. Based on the RSM approach, the optimization conditions for maximum removal efficiency is obtained at pH = 3, adsorbent dosage = 4 g/L, contact time = 30 min, and initial pesticide concentration = 6.2 mg/L. To accurately identify the parameters of nonlinear isotherm and kinetic models, a hybrid evolutionary differential evolution optimization (DEO) is applied. Results indicated that the equilibrium adsorption data were best fitted with Langmuir and Temkin isotherms and kinetic data were well described by pseudo-first and second-order kinetic models. The thermodynamic parameters such as entropy, enthalpy and Gibbs energy were evaluated to study the effect of temperature on pesticide adsorption.

Background and purpose: Styrene, one of the most important compounds of VOCs, causes some health concern. In current study, the ability of ZSM5, TiO2/ZSM5, UV/ ZSM5, and UV/TiO2/ZSM5 methods was investigated in removing styrene from air synthetic current. Materials and methods: In order to synthesize the zeolite and TiO2-coated zeolite, the sol-gel and saturation methods were employed, respectively. In this study, the effect of the type of removal process, saturation time and initial pollutant concentration were investigated on the removal of styrene in a photoreactor. Phocheck device with direct reading system was applied to determine the output concentration. Also, SEM, XRD, EDX, and BET analyses were used to characterize the chemical and physical properties of ZSM5, and TiO2/ZSM5. Results: SEM analysis showed that zeolite has a crystal form, and TiO2 successfully covered the surface of this compound. In addition, the EDX analysis demonstrated that a great part of zeolite structural includes Al and Si constituents. The XRD pattern showed the presence of attached TiO2 in the zeolite structure. BET analysis revealed that the surface area of zeolite decreased when TiO2 was coated on its surface. The order of increase in removal efficiency was as follows: UV/TiO2/ZSM5 > ZSM5> TiO2/ZSM5. The saturation time of ZSM5 and TiO2/ZSM5 in the 300 ppm concentration was 370 and 280 min, respectively, while the outlet concentration in the UV/TiO2/ZSM5 method was fixed at 74% removal efficiency after elapsing 310 min. The increment of time exposure and initial styrene concentration also led to decrease in removal efficiency. Conclusion: In this study application of UV/TiO2/ZSM5 process provided a higher efficiency of the styrene removal than that of TiO2/ZSM or ZSM5 in the same time.

Background and Objectives: Synthetic dyes are an important group of additivesused in food products, and because of health concerns about consuming population, the application of these compounds is needed to be enough controlled. The aim of this study was to investigate the types and frequencies of the dyes used in making pastries in the confectionery of Tuyserkan city. Materials and Methods: In this cross-sectional study investigated the types of consumed dyes in confectionery’s pastries of Tuyserkan city. A total of 80 samples including wet and dry pastries are randomly sampled from 17 confectioneries. The steps of the experiment consisted of degreasing the sample, purification, and determining the type of dye were down by using Tin Layer Chromatography (TLC) method. All charts used in the study were drowned by Excel Software (2013). Results: The results indicate, among the total 80 samples, 17 samples contained no dye, 15 samples with natural dye, 44 samples with permitted synthetic dyes, and 4 samples have non-permitted synthetic dyes. Moreover, of all the synthetic dyes, 8 samples contained Quioline yellow dye, 10 samples with Sanset yellow dye, 8 samples with Azorubine dye, 5 samples with Brilliant blue dye, 5 samples with ponceau 4R, and 4 (5%) samples have Allura Red. Conclusions: This study showed a remarkable part of used dyes in the confectionery of Tuyserkan city is non-permitted. Therefore, it is proposed to reduce the amount of synthetic dyes by restriction in distribution, more controlling by health departments, and increasing the awareness in consumers and manufactures.

Introduction and Aims: Pharmaceutical pollutants in aqueous can cause a number of health problems for people and other creatures. In this study, a survey of Dexamethasone removal from synthetic aqueous solutions was investigated by using UV/S2O8 and UV/H2O2 methods. Materials and Methods: This experimental study carried out at lab scale at a reactor with the batch flow. In this study, the parameters of time (5- 60 min), pH (3, 7 and 11), dose of S2O8 (0.1-7.5 mM), dose of H2O2 (0.1- 7.5 mM), and Dexamethasone concentration (5- 20 mg/L) were studied to specify their effects on Dexamethasone removal. Furthermore, the remaining concentration of dexamethasone was determined by spectrophotometer DR (model 5000) in the 241 nm wavelength. Results: Results showed that with the increasing amount of parameters of pH, retention time, and a dose of H2O2 and S2O8 and with decreasing parameter of dexamethasone concentration, removal efficiency raised. Removal efficiencies of dexamethasone in the optimum condition of time=40, pH=3 and dexamethasone concentration = 5 mM was obtained 47, 59, 82, 91, and 98 percent for UV/S2O8 concentrations of 0.1, 0.5, 1.5, 5, and 7.5 mM, and 19, 49, 61, 65, and 72 percent for UV/H2O2, respectively. Conclusion: According to higher removal efficiencies of UV/S2O8 method than UV/H2O2, easier storage and moderate stability of S2O8 and also more oxidation ability of SO4- than OH°, it is better to apply UV/S2O8 method to degradation of dexamethasone.

Background and purpose: Today, due to improvement and progress of human knowledge in food industry, plastic coatings such as PET (polyethylene terephthalate) that has unique characteristics are widely used for food and beverage packaging such as water and doogh. Phthalate esters are used in order to improve flexibility, efficiency and sustainability of materials. Chronic exposure with such materials play a role in incidence of many diseases and cancer in human. The aim of this study was to investigate the presence and concentration of phthalates in different brands of doogh. Materials and methods: In this study, we synthesized multi-walled magnetic carbon nanotubes using iron oxide. Then, the synthesized magnetic nanotubes were used for absorption and extraction of phthalate esters from doogh matrix. After sample preparation, the concentration of each phthalate esters was measured by GC-MS. Results: Concentration of phthalate esters in all samples were found to be lower than the standard levels but DEHP had the highest concentration. Statistical analysis showed no significant differences between the concentration of phthalate esters in different brands and storage time of doogh. Conclusion: According to these findings and low concentration of each phthalate ester compared with standard levels in different types of doogh, it has no health effect on consumers.

BACKGROUND: Helicobacter pylori (H. pylori) infection is thought to play an etiologic role in several gastroduodenal diseases including gastric ulcer, duodenal ulcer, gastric MALT lymphoma, and distal gastric cancer. Several studies have suggested that H. pylori which express cytotoxin-associated gene A (CagA) may be more virulent than those that do not, but limited populations have been studied to date. The aims of the present study were to evaluate the seroprevalence of anti-H. pylori IgG, IgA and anti-CagA antibodies in peptic ulcer (PU) patients and healthy individuals in the city of Rafsanjan. METHODS: A total of 60 PU patients (30 males and 30 females, aged 17 to 60 years) and 138 age-matched healthy individuals (65 males, 73 females) were enrolled in this study. Diagnosis of PU disease was established on the basis of findings by gastrointestinal endoscopy. The control group was recruited from among healthy blood donors referred to Blood Transfusion Center of Rafsanjan. A blood sample was collected from each participant and the sera were tested for the presence of anti- H. pylori IgG and IgA antibodies and antibody to bacterial virulence factor (CagA) by use of enzyme-linked immunosorbent assay. The serum concentrations of anti-H. pylori IgA and anti-CagA antibody were expressed as mean ± SD in each group. RESULTS: In PU patients the overall seroprevalence of anti-H. pylori IgG (95.8%), IgA (96.6%) and anti-CagA (91.6%) were higher than those observed in the control group (73.2%, P