Isotherm and kinetic studies on adsorption of gasoline and kerosene using jujube and barberry tree stem powder and commercially available activated carbon

Herein, the application of granular activated carbon, jujube, and barberry tree stem powder for the removal of gasoline and kerosene from water was investigated. Kerosene removal rates upwards of 68.48, 83.87, and 99.02% were achieved using jujube tree stem powder, barberry tree stem powder, and granular activated carbon, respectively. Besides, gasoline removal rates upwards of 69.35, 55.02, and 95.59% were attained using jujube tree stem powder, barberry tree stem powder, and granular activated carbon, respectively. Isotherm data were further investigated and fitted using Langmuir, Freundlich, and Elovich models. The results indicated that the adsorption onto jujube adsorbent is a multilayer adsorption process over a heterogeneous surface, which is best illustrated by the Temkin (Ave. R2= 0.95) model. It was found that the Temkin isotherm (Ave. R2= 0.81) best describes the properties of barberry stem powder in the adsorption of gasoline and kerosene from water. Moreover, the best models to describe the characteristics of granular activated carbon in the adsorption of gasoline and kerosene from water were Freundlich (Ave. R2= 0.74) and Langmuir (Ave. R2= 0.73) isotherms, respectively. The adsorption kinetics showed that the pseudo-second-order was appropriate in modeling the adsorption kinetics of gasoline and kerosene to the studied adsorbents (R2>0.74).

Investigating the improvement of the quality of industrial effluents for reuse with added processes: coagulation, flocculation, multi-layer filter and UV

Reuse of wastewater is one of the ways to develop water resources. In addition to the need for drinking water, many industries also need high-quality water in the production line. Therefore, the purpose of the present study is to investigate the advanced treatment of the wastewater treatment plant of Morche Khort industrial town using the processes of coagulation, flocculation with aeration, multi-layer filter, and disinfection by ultraviolet radiation to increase the quality of wastewater and reuse it in industries. In this study, to investigate the effect of coagulation and flocculation units along with aeration, filtration, and disinfection by ultraviolet rays (UV), on the quality of the secondary effluent from the wastewater treatment plant of Morche Khort industrial town, they were operated on a pilot scale. Polyaluminum chloride (PAC) was used as a coagulant. Layering of three layers of sand filter, from bottom to top including granulated silica at a height of 10 cm, sand at a height of 20 cm, and activated carbon at a height of 70 cm was used. The input and output sampling points of each unit were considered. By repeating twice in five stages of flow rates of 1, 2, 4, 6, and 8 (L/min), the samples were collected to determine COD, TSS, TDS, turbidity, pH, hardness, total coliform, and fecal coliform. Jar test results showed that Alum coagulant works almost the same as PAC in removing turbidity, but the efficiency of removing organic substances by PAC coagulant is higher than that of Alum at lower doses. The results of this study showed that the efficiency of the coagulation and flocculation process in removing turbidity, COD, TSS, TDS, and fat was 56.88%, 46.66%, 38%, 23.19%, and 91.43% respectively. In the current study, the results of the wastewater entering the sand filter showed that the percentage of removal efficiency with a loading rate of 1 (L/min) was turbidity, TSS, COD, TDS, and fat was 16. 93%, 56.84%, 50%, 5.67%, 33.44% respectively. In the UV disinfection unit, the removal efficiency percentage with a loading rate of 1 (L/min) for COD, TSS, turbidity, hardness, total coliform, and fecal coliform is 16%, 3.45%, 3.58%, 5.21%, 99.88%, and 98.37% respectively. Coagulation and flocculation system-multi-layer filter and disinfection can remove chemical-physical and microbial parameters to an acceptable level for using water in advanced purification systems and also for irrigation.

Catalytic electrodes' characterization study serving polluted water treatment: environmental healthcare and ecological risk assessment

Pesticide residues in the environment have irreparable effects on human health and other organisms. Hence, it is necessary to treat and degrade them from polluted water. In the current work, the electrochemical removal of the fenitrothion (FT), trifluralin (TF), and chlorothalonil (CT) pesticides were performed by catalytic electrode. The characteristics of SnO2-Sb2O3, PbO2, and Bi-PbO2 electrodes were described by FE-SEM and XRD. Dynamic electrochemical techniques including cyclic voltammetry, electrochemical impedance spectroscopy, accelerated life, and linear polarization were employed to investigate the electrochemical performance of fabricated electrodes. Moreover, evaluate the risk of toxic metals release from the catalytic electrode during treatment process was investigated. The maximum degradation efficiency of 99.8, 100, and 100% for FT, TF, and CT was found under the optimal condition of FT, TF, and CT concentration 15.0 mg L-1, pH 7.0, current density 7.0 mA cm-2, and electrolysis time of 120 min. The Bi-PbO2, PbO2, and SnO2-Sb2O3 electrodes revealed the oxygen evolution potential of 2.089, 1.983, 1.914 V, and the service lifetime of 82, 144, and 323 h, respectively. The results showed that after 5.0 h of electrolysis, none of the heavy metals such as Bi, Pb, Sb, Sn, and Ti were detected in the treated solution.

Application of artificial neural network and dynamic adsorption models to predict humic substances extraction from municipal solid waste leachate

Sustainable municipal solid waste leachate (MSWL) management requires a paradigm shift from removing contaminants to effectively recovering resources and decreasing contaminants simultaneously. In this study, two types of humic substances, fulvic acid (FA) and humic acid (HA) were extracted from MSWL. HA was extracted using HCl and NaOH solution, followed by FA using a column bed under diversified operations such as flow rate, input concentration, and bed height. Also, this work aims to evaluate efficiency of Artificial Neural Network (ANN) and Dynamic adsorption models in predicting FA. With the flow rate of 0.3 mL/min, bed height of 15.5 cm, and input concentration of 4.27 g/mL, the maximum capacity of FA was obtained at 23.03 mg/g. FTIR analysis in HA and FA revealed several oxygen-containing functional groups including carboxylic, phenolic, aliphatic, and ketone. The high correlation coefficient value (R²) and a lower mean squared error value (MSE) were obtained using the ANN, indicating the superior ability of ANN to predict adsorption capacity compared to traditional modeling.

Decolorization, COD and turbidity removal of the raw vinasse effluent by a one-step electro-oxidation process on a Pb/PbO2 anode

In this research, and for the first time, the application of anode Pb/PbO2 (prepared from combined thermal oxidation and electrochemical oxidation method) and steel cathode in a flow sample electrochemical treatment process of vinasse and in the wastewater of alcohol factories, has been investigated. The combination of electrodes of Pb/PbO2 as an anode, steel, and/or graphite as a cathode was used in the proposed electrochemical treatment setup. The efficiency of the proposed electrochemical treatment was determined by the removal percentage of chemical oxygen demand (COD), turbidity and color of vinasse samples. The response surface method (RSM) by Minitab 18 was used to determine the effect of the studied factors as well as to detect the relationship between variables. The results showed that under optimum conditions (Pb/PbO2 electrode as the anode and steel electrode as the cathode, a voltage of 30 V, pH 6.5, and reaction time of 45 min), the percentage reduction values of COD, turbidity and color were 97.7, 77.3 and 92.7%, respectively.

Burden of road traffic injuries in Iran: a national and subnational perspective, 1990-2019

OBJECTIVES

Reliable and valid information on burden of road traffic injuries (RTIs) is essential for short-term and long-term planning. We designed the present study to describe the levels and trends of burden of RTIs in Iran from 1990 to 2019.

METHODS

This is an observational epidemiological study. We used the Global Burden of Disease (GBD) 2019 estimates to report RTIs incidence, prevalence, mortality and disability-adjusted life-years (DALYs) by sex, age group and road user category in Iran and each of the 31 provinces from 1990 to 2019.

RESULTS

Age-standardised incidence, prevalence, death and DALY rates of RTIs decreased by 31.7% (95% uncertainty interval (UI): 29.4 to 33.9), 34.9% (33.8 to 36.0), 57.7% (48.1 to 62.3) and 60.1% (51.7 to 65.2), respectively between 1990 and 2019. The 2019 age-standardised DALY rates varied from smallest value in Tehran 303.8 (216.9 to 667.2) per 100 000 to largest value in Sistan-Baluchistan 2286.8 (1978.1 to 2627.9) per 100 000. The burden of RTIs was mainly related to injuries sustained by drivers or passengers of motorised vehicles with three or more wheels and pedestrians' injuries, mostly affected males aged 15-29 years and individuals aged ≥70 years.

CONCLUSION

The reducing trend in the burden of RTIs in Iran possibly reflects the effectiveness of the intervention programmes. However, with regard to the Sustainable Development Goals the burden is still at an alarming level. Further reductions are necessary for specific road user groups such as adolescent and adult male drivers or passengers of motorised vehicles, also pedestrians aged ≥70 years.

Evaluation of rheological and optical properties plus stability of beverage cloud emulsions prepared with corn oil, gum rosin, and modified starch

Rheological and optical properties as well as stability of beverage cloud emulsion prepared with corn oil, gum rosin (EG), and modified starch were evaluated in model juices. The emulsions were prepared with three levels of modified starch (6%, 12%, and 18% w/w), corn oil (5%, 7%, and 9% w/w), and gum rosin (1%, 3%, and 5% w/w). Experiments were designed using the Box-Behnken design. The analysis of variance (ANOVA) was used to evaluate the significance of the experimental factors and the factors were then optimized using response surface methodology (RSM). The stability of emulsions was measured through ring formation in both the primary emulsion and the model beverage as a function of storage time. Also, the effect of heat treatment was examined on the stability of emulsions in model beverages. The results revealed that heat treatment did not cause the formation of an observable ring in the model juice containing stabilized starch emulsion. Rheological examinations of the stable emulsion samples showed a pseudoplastic and time-independent non-Newtonian behavior. The optimum emulsion sample consistency coefficient was 0.46 Pa.sn and the flow behavior index was 0.88. The apparent viscosity of the optimum emulsion sample based on Herschel-Bulkley model at shear rate of 100 s-1 was 0.0439 Pa.s. The results indicated that the concentration of modified starch, gum rosin, and corn oil has a significant effect on the stability and creaminess of the emulsion. In general, with an increase in the percentage of modified starch, the stability rises while the rate of creaminess decreases (p < 0.05). Furthermore, elevation of the concentration of corn oil had a significant effect on the opacity of emulsions and the final product (p < 0.05).

Simultaneous electrochemical degradation of pesticides from the aqueous environment using Ti/SnO2-Sb2O3/PbO2/Bi electrode; process modeling and mechanism insight

In this work, modified Bi-PbO₂ electrode was fabricated and employed for simultaneous degradation of fenitrothion (FT), trifluralin (TF), and chlorothalonil (CT) from synthetic and pesticide wastewater through the anodic oxidation process. A novel high-performance liquid chromatography method was developed and optimized to identify the pesticides simultaneously. Quadratic models were developed to investigate the effects of main operating parameters and predict the degradation efficiencies of the treatment processes. The R² of the degradation efficiencies were obtained of 0.9847, 0.9910, and 0.9821 for FT, TF, and CT, respectively, which indicates the degree of conformity between the experimental and the actual values of degradation efficiencies, and the adjusted R² values for the degradation efficiency of FT, TF, and CT in proposed models were 0.9826, 0.9898, and 0.9796, and the values of the predicted R² were 0.9792, 0.9875, and 0.9755, respectively. The maximum degradation efficiencies of 99.7, 100, and 100% obtained for FT, TF, and CT, respectively, under the optimal operating condition of FT, TF, and CT concentration of 10.0, 6.0, and 8.0 mg L^-1, respectively, pH 6.0, the current density 6.0 mA cm^-2, and electrolysis time of 60 min. Chemical oxygen demand removal and energy consumption were 64.7% and 5.1 kWh m^-3. Eventually, the generated intermediates and other produced species of pesticides through the treatment process was evaluated using a gas chromatography-mass spectrometry method, and their degradation pathways were proposed.

The challenges of strategic management of the wastage produced due to earthquake in Kermanshah and Varzaghan-Ahar: A qualitative study

BACKGROUND

Strategic management of the wastage produced due to earthquakes has faced many challenges over the recent decade. Thus, the present study seeks to identify and explain the challenges in earthquake wastage strategic management.

MATERIALS AND METHODS

The present qualitative study has been steered through a content analysis approach and conducted using semi-structured interviews and a purposive selection of 17 professors, experts, and managers experienced in the field of waste management in Kermanshah and Varzaghan-Ahar earthquakes over 2020-2021. Besides, the interviews were initially categorized using MAXQDA18 software.

RESULTS

Analysis of the experiences and perception regarding the changes in strategic management of wastage produced due to Kermanshah and Varzaghan-Ahar earthquakes revealed 418 codes, 97 subcategories, 33 categories, and 8 main categories including management and leadership, organizational culture, planning, organizational learning, employee management, rules and regulations, resource management, and procedure management.

CONCLUSION

Strategic waste management has not been implemented in a coherent, integrated, and well-planned manner in the cases of the Kermanshah and Varzaghan-Ahar earthquakes. The challenges of strategic waste management turned out to be due to various reasons which will result in many issues in achieving the goals and selecting the suitable method for resource and procedure management should they not be managed well. Hence, policymakers, managers, and executors in the field of crisis management and waste management in disasters -specifically earthquakes- must take the necessary measures to remove these barriers.

Cometabolic bacterial and fungal remediation as a promising strategy for recycled paper and cardboard mill wastewater treatment

Purpose

This paper aims to study the application of high-tolerance and flexible indigenous bacteria and fungi, along with the co-metabolism in recycled paper and cardboard mill (RPCM) wastewater treatment (WWT).

Design/methodology/approach

The molecular characterization of isolated indigenous bacteria and fungi was performed by 16S rRNA and 18S rRNA gene sequencing, respectively. Glucose was used as a cometabolic substrate to enhance the bioremediation process.

Findings

The highest removal efficiency was achieved for both chemical oxygen demand (COD) and color [78% COD and 45% color removal by Pseudomonas aeruginosa RW-2 (MZ603673), as well as approximately 70% COD and 48% color removal by Geotrichum candidum RW-4 (ON024394)]. The corresponding percentages were higher in comparison with the efficiency obtained from the oxidation ditch unit in the full-scale RPCM WWT plant.

Originality/value

Indigenous P. aeruginosa RW-2 and G. candidum RW-4 demonstrated effective capability in RPCM WWT despite the highly toxic and low biodegradable nature, especially with the assistance of glucose.

Indigenous bacteria as an alternative for promoting recycled paper and cardboard mill wastewater treatment

The present study aimed to investigate indigenous bacteria possibility in recycled paper and cardboard mill (RPCM) wastewater treatment through the isolation and identification of full-scale RPCM indigenous bacteria. The molecular characterization of the isolated bacteria was performed by 16S rRNA gene sequencing. Klebsiella pneumoniae AT-1 (MZ599583), Citrobacter freundii AT-4 (OK178569), and Bacillus subtilis AT-5 (MZ323975) were dominant strains used for RPCM wastewater bioremediation experiments. Under optimal conditions, the maximum values of chemical oxygen demand (COD) and color biodegradation by C. freundii AT-4 were 79.54% and 43.81% after 10 days of incubation, respectively. In the case of B. subtilis strain AT-5 and K. pneumoniae AT-1, the maximum values of COD and color biodegradation were 70.08%, 45.96%, 71.26%, and 32.06%, respectively. The results from optimal conditions regarding efficiency were higher in comparison with the efficiency obtained from the oxidation ditch treatment unit in full-scale RPCM-WWTP. Therefore, the present study introduces the isolated indigenous bacteria strains as a promising candidate for improving the RPCM-WWTP efficiency using bioremediation.

Formulation optimization of functional wheat bread with low glycemic index from technological and nutritional perspective

Inclusion of prebiotic compounds as indigestible dietary fiber in wheat bread has grown rapidly considering the increased public awareness about their impact on health. However, through their incorporation, the technological characteristics may adversely be influenced by gluten dilution impacts. This study was done to evaluate the impacts of long chain, native and short chain inulin (L-, N-, and S-type inulin, respectively) at 8%, 10%, 12%, 14%, and 16% w/w as Inulin Reconstituted Wheat Flour (IRWF) with similar gluten: carbohydrate ratio of wheat flour (at 10%, 12.5%, 15%, 17.5%, 20% w/w) on technological and nutritional value of wheat bread. Results indicated that despite no gluten dilution induced by IRWF supplementation, technological characteristics were adversely influenced especially at higher substitution level of L-type-containing formulations which is attributed to their higher water absorption index (WAI). Reversely, the nutritional value was positively influenced in which the lowest hydrolysis index (26.64%); predicted Glycemic Index (51.93%) and fructan loss content (25.42%) were found at L-type inulin-containing IRWF at the highest substitution level (20% w/w). As the nutritional value of wheat bread as staple foodstuff is important, optimizing the bread-making process to decrease all reverse impacts induced by L-inulin-type inclusion seems to be required.

Relationship between Serum Tumor-Related Markers and Genetically Modified Rice Expressing Cry1Ab Protein in Sprague-Dawley Rats

Genetically Modified (GM) foods are among the most important achievements of biotechnology. Given the safety importance of transgenic rice, this study was conducted to investigate the effect of GM rice consumption on serum concentrations of tumor markers in rats. In this experimental intervention, we used the blood serum samples from the Biobank taken from 60 males and 60 female Sprague-Dawley (SD) rats fed on three different diets, including rat's standard food, non-GM rice, and GM rice after 90 day. Tumor markers including Carcinogenic embryonic antigen (CEA), Alpha-Fito protein (AFP), Cancer Antigen 19-9 (CA19-9), Cancer Antigen 125 (CA125), and Cancer Antigen15-3 (CA15-3) were assessed by enzyme-linked immune sorbent assay (ELISA) method. Statistical analysis was conducted via SPSS software. The results show that the concentrations of tumor markers were within the normal range in the SD rats treated with diet, and since the concentration of tumor markers was lower than the acceptable index determined, according to the kit standard in both groups, no obvious carcinogenic effect was found. However, these findings are not enough to make a final decision regarding the safety assessment of GM rice consumption.

Risk assessment and disease burden of legionella presence in cooling towers of Iran's central hospitals

Regular monitoring and measurement of Legionella in tower water and preventive measures against contamination are particularly important in hospitals. This study aimed at risk assessment and disease burden because of legionella presence in cooling towers of Iran's central hospitals. Then its correlation with temperature, pH, turbidity, residual chlorine, and EC was investigated by the Pearson test. The health risk and burden of diseases caused by Legionella exposure were determined using QMRA and DALY models. Statistical analysis and modeling were performed in MATLAB₂₀₁₈. Of the total samples, 30-43% was infected with Legionella. The mean concentrations in hospital A and B were 5-102.5 ± 10 and 5-89.7 ± 0.7 CFU/L, respectively. Among environmental factors, turbidity and pH were the most effective factors in increasing and decreasing Legionella concentration, respectively. According to the QMRA model, the risks of Legionella infections and annual mortality in both hospitals were 0.2-0.3, 0-0.19, 2-2.9 × 10^-5, and 0-0.7 × 10^-5, respectively, which was higher than the acceptable risk range for Legionella (10-4-10-7). However, the trend of its change was negatively correlated with time (R_B = - 0.77). According to the results, the concentration of Legionella and the exposure risk in both hospitals were higher than the permissible range, which is necessary to decrease to 0.1 current concentrations.

Antibiotic resistance and class 1 integron genes distribution in irrigation water-soil-crop continuum as a function of irrigation water sources

The increasing demand for fresh water coupled with the need to recycle water and nutrients has witnessed a global increase in wastewater irrigation. However, the development of antibiotic resistance hotspots in different environmental compartments, as a result of wastewater reuse is becoming a global health concern. The effect of irrigation water sources (wastewater, surface water, fresh water) on the presence and abundance of antibiotic resistance genes (ARGs) (bla_CTX-m-32, tet-W, sul1, cml-A, and erm-B) and class 1 integrons (intI1) were investigated in the irrigation water-soil-crop continuum using quantitative real-time PCR (qPCR). Sul1 and bla_CTX-m-32 were the most and least abundant ARGs in three environments, respectively. The abundance of ARGs and intI1 significantly decreased from wastewater to surface water and then fresh water. However, irrigation water sources had no significant effect on the abundance of ARGs and intI1 in soil and crop samples. Principal component analysis (PCA) showed that UV index and air temperature attenuate the abundance of ARGs and intI1 in crop samples whereas the air humidity and soil electrical conductivity (EC) promotes the ARGs and intI1. So that the climate condition of semi-arid regions significantly affects the abundance of ARGs and intI1 in crop samples. The results suggest that treated wastewater might be safely reused in agricultural practice in semi-arid regions without a significant increase of potential health risks associated with ARGs transfer to the food chain. However, further research is needed for understanding and managing ARGs transfer from the agricultural ecosystem to humans through the food chain.

Technological characteristics of inulin enriched gluten-free bread: Effect of acorn flour replacement and fermentation type

Textural, physicochemical, and sensory characteristics of rice-based gluten-free bread in the presence of acorn flour; inulin and different fermentation type (yeast starter fermentation [Y] or mixed fermentation based on sourdough [MF-SD]) were investigated. Acorn flour was added to replace rice flour at a proportion of 10, 30, and 50% W/W. Furthermore, the mixture flour was replaced by inulin as a functional prebiotic ingredient at 10% W/W. Considering results obtained at this study, using mixed fermentation based on sourdough and inulin at 10% W/W provide the structure able to restore gases through baking process at formulations containing acorn flour at 30% W/W (A30R70SL). The highest specific volume (1.47 ± 0.04 cm3 g-1) and the lowest hardness (40.97 ± 0.87 N) are observed in A30R70SL which seems to be induced by its potential to form gel. Acorn flour substitution level at 50% W/W adversely influenced the technological characteristics of final product and its perception by the consumer. Acorn flour substitution up to 30% W/W is preferred by the consumer which is attributed to its potential role to improve the unpleasant pale color of rice-based gluten-free products. A negatively significant correlation has been observed between the color perception by the consumer and crumb lightness (r = -.493, p ≤ .05).

Enhanced photocatalytic activity of efficient magnetically recyclable core-shell nanocomposites on 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153) degradation under UV-LED irradiation

The congener polychlorinated biphenyls (PCBs) are one of the of persistent organic pollutant compounds that increase lifestyle-related diseases, such as diabetes, obesity, and cancer. So, 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153), which is one of the most common PCB contaminants in nature, was selected as a model compound to study the photocatalytic degradation of Fe₃O₄@SiO₂@TiO₂ core-shell structure. In this work, Fe₃O₄@SiO₂@TiO₂ nanocomposite was synthesized and characterized using transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), energy-dispersive X-ray (EDS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM) techniques. Then, the effect of parameters such as catalyst dosage, initial concentration of PCB 153, solution pH, amount of H₂O₂, and kind of co-solvent on photocatalytic degradation of PCB 153 by the synthesized nanocomposite was investigated. The high degradation efficiency of Fe₃O₄@SiO₂@TiO₂ nanocomposite, which was 96.5%, was obtained at 4 g/l of the catalysts, 4 ppm of PCB 153, pH 5, 20 mM H₂O₂, 2 h of reaction time, and acetone as a cosolvent. Also, the rate of mineralization for Fe₃O₄@SiO₂@TiO₂ nanocomposite with H₂O₂ and UV-LED irradiation was 75.3% which had a significant efficiency compared to control experiments. Moreover, the mentioned photocatalysts are possible to be reused through exposing to external magnetic field, with insignificant decrease in the catalytic activity even after 6 cycles. The photocatalytic degradation process has an effective and environmental friendly effect on the degradation of organic pollutants.

Tracking antibiotic resistance genes and class 1 integrons in Escherichia coli isolates from wastewater and agricultural fields

Considering high concentrations of multidrug-resistant bacteria and antibiotic resistance genes (ARGs) in wastewater, agricultural reuse of treated wastewater may be a public health threat due to ARG dissemination in different environmental compartments, including soil and edible parts of crops. We investigated the presence of antibiotic-resistant Escherichia coli as an indicator bacterium from secondary treated wastewater (STWW), water- or wastewater-irrigated soil and crop samples. ARGs including bla_CTX-m-32, bla_OXA-23, tet-W, sul1, cml-A, erm-B, along with intI1 gene in E. coli isolates were detected via molecular methods. The most prevalent ARGs in 78 E. coli isolates were sul1 (42%), followed by bla_CTX-m-32 (19%), and erm-B (17%). IntI1 as a class 1 integrons gene was detected in 46% of the isolates. Cml-A was detected in STWW isolates but no E. coli isolate from wastewater-irrigated soil and crop samples contained this gene. The results also showed no detection of E. coli in water-irrigated soil and crop samples. Statistical analysis showed a correlation between sul1 and cml-A with intI1. The results suggest that agricultural reuse of wastewater may contribute to the transmission of antibiotic-resistant bacteria to soil and crop. Further research is needed to determine the potential risk of ARB associated with the consumption of wastewater-irrigated crops.

Predicting anionic surfactant toxicity to Daphnia magna in aquatic environment: a green approach for evaluation of EC50 values

The median effective concentration (EC₅₀) is the concentration of a substance expected to produce a specific effect in 50% of the populations with a certain density under defined conditions. This parameter is expressed as an acute toxicity and is obtained via chemical toxicity testing. But, the laboratory work is time-consuming, expensive, and not eco-friendly. Therefore, to predict EC₅₀ for new anionic surfactants, a quantitative structure-activity relationship (QSAR) tool was studied for modeling the EC₅₀ of anionic surfactants on Daphnia magna based on the molecular descriptors. The best model (R² = 0.901 and F = 118.077, p<0.01) included 3 variables of the number of carbons, hydrogens, and the octanol-water partition coefficient logarithm. The main contribution to the toxicity was the octanol-water partition coefficient logarithm descriptor that had a negative effect on the toxicity of surfactants. The QSAR approach exhibited good results in predicting anionic surfactants EC₅₀, which allows the building of a simple, valid, and interpretable model that can be utilized as potential tools for rapidly predicting the lnEC50 of new or untested anionic surfactants to Daphnia magna.

Investigation of the association between pesticide exposure and the prevalence of type 2 diabetes in Shahedieh population in Yazd

This study aimed to investigate the effect of exposure to pesticides and the prevalence of type 2 diabetes (T2D). In a cross-sectional study with a population of 9088, the data were collected through Persian Adult Cohort Questionnaire in Shahedieh area of Yazd, Iran. Based on the results, variables such as age, gender, body mass index, physical activity, and education level in the studied population had a significant association with the prevalence of diabetes. Although the obtained data in this study did not show a relationship between exposure to pesticides and the risk of developing T2D, further prospective studies are needed to determine the association between exposure to pesticides and the development of T2D.

Comparison of poly ferric chloride and poly titanium tetrachloride in coagulation and flocculation process for paper and cardboard wastewater treatment

The current study investigated the efficiency of poly ferric chloride (PFC) and poly titanium tetrachloride (PTC) in coagulation-flocculation process for treatment of paper and cardboard wastewater. The effect of pH (5-11), coagulant concentrations (100-1000 mg/L), mixing rate (10-60 rpm), mixing time (5-25 min), and settling time (5-30 min) were examined. The results showed that the removal efficiency for turbidity, total suspended solids (TSS), and chemical oxygen demand (COD) by PFC and PTC coagulants increased with pH rising up to 9 for the former and 7 for the latter coagulant. Furthermore, the removal efficiency for the afore-mentioned parameters increased along with a 30 rpm increase in the mixing rate, while the mixing time reached 20 min. It was also found that the best removal efficiencies for turbidity, TSS, and COD by PFC under optimal conditions (pH 9, coagulant dose 800 mg/L, and settling time of 25 min) were 97.11%, 99.1%, and 84.91%, respectively. In addition, the removal efficiencies for PTC (optimal conditions of pH 7, coagulant dose 600 mg/L, and settling time of 15 min) were found to be 98.29%, 99.29%, and 86.42%, respectively. Water recovery and the produced sludge volume by PFC were 80% and 200 cm³, respectively, in the settling time of 25 min and for PTC were 81.5% and 185 cm³, respectively, in the settling time of 15 min. Costs of the coagulation-flocculation process for treatment 1 m³ of paper and cardboard wastewater using PTC and PFC were 0.42 $ and 0.32 $, respectively. Finally, it can be concluded that compared to PFC, PTC with higher settling rate has a greater efficiency for treatment of paper and cardboard wastewater.

Is there a relationship between homes' radon gas of MS and non-MS individuals, and the patients' paraclinical magnetic resonance imaging and visually evoked potentials in Yazd-Iran?

Long-term inhalation of radon gas can cause harm to humans and lead to many diseases. One of these diseases is multiple sclerosis (MS), the most common chronic disease of the central nervous system, which alters the brain structure and impedes the rapid transmission of nerve signals throughout the neuron system. Therefore, this study aimed to investigate the relationship of the radon gas concentration in residential homes of MS and non-MS individuals with their results of paraclinical MRI and VEP in Yazd City, Iran. The radon gas concentration was measured in residential homes of 44 people with MS and 100 healthy people. To this end, the questionnaire of radon gas monitoring in residential buildings was administered, and the radon gas concentration was measured by CR-39 detectors. The mean radon concentrations in the homes of MS and non-MS people were 69.51 and 70.83, respectively. A significant positive relationship was found between radon concentration and building's age (P = 0.038). Furthermore, radon concentration had a significant inverse relationship with the building's ventilation (P = 0.053) and cooling systems (P = 0.021). No significant relationship was observed between total radon concentration and MS incidence (P = 0.88). Moreover, no significant correlation was found between radon concentration and location of the plaque in MRI test results of the patients. However, it showed an inverse non-significant correlation with the plaque's number (r = - 0.12, P = 0.42). Further studies in this area are recommended.

Safety assessment of genetically modified rice expressing Cry1Ab protein in Sprague-Dawley rats

Rice is considered one of the most important staple food crops. Genetically modified (GM) Bt rice, harbored cry1Ab gene expressing the insect-resistance protein has been developed to resistance to the insects. In this study, we assessed the safety of the GM Bt rice on Sprague–Dawley rats for 90 days. Totally, 120 rats in both sexes were used for three different diets, including 50% GM Bt rice, feeding with 50% rice, and standard feeding. Each 40 SD rats including 20 males and 20 females were considered as each diet. The clinical variables such as body weight and food consumption were measured and a range of clinical tests was examined, including hematology, serum chemistry parameters, urinalysis profile, thyroid, and sex hormone levels. Pathological assessments were also done. The results showed that the mean weekly feed utilization (%) had no significant difference among the studied groups. Also, blood biochemistry, hematological parameters, urine analysis, and hormonal levels had no significant differences among the groups. However, alanine aminotransferase was less in males versus female feeding with GM Bt rice. No histopathological changes were observed among the groups. In conclusion, this study demonstrated that GM Bt rice had no obvious adverse effects on rats' health.

Evaluating changes in microbial population and earthworms weight during vermicomposting of cow manure containing co-trimoxazole

BACKGROUND

Transmission of pathogens such as fecal coliforms is regarded as a significant concern about using livestock manure in agricultural applications.

PURPOSE

The aim of this study was to evaluate the effects of vermicomposting on fecal coliforms in cow manure containing co-trimoxazole as a widely used drug for cow diseases in animal husbandry.

METHODS

Adaptation process of earthworms was carried out in two phases for 6 weeks; then, the main process was fulfilled in 9 weeks. The final weight of cow manure per reactor was 3.5 kg. 120 g of earthworms added to each reactor (approximately 280-300 numbers in the reactor). Co-trimoxazole was also prepared with a purity of 99% from Pakdarou Co., Iran, and added to the reactors at concentrations of 10, 20, 50, and100mg/kg. Organic carbon, total Kjeldahl nitrogen (TKN), carbon-to-nitrogen (C:N) ratio, as well as phosphorus content of the reactors were measured. Fecal coliforms and parasite eggs were counted using standard laboratory methods (i.e. the Iranian Compost Standard) for 8 weeks.

RESULTS

The results revealed a decrease in organic carbon, C:N ratio, and co-trimoxazole content but a rising trend in TKN and phosphorus levels. The weight of earthworms also increased at the end of the process in all reactors, except for one case. A significant reduction was observed in fecal coliforms and parasite eggs at the end of the vermicomposting.

CONCLUSIONS

According to the results, earthworms could be active in cow manure vermicomposting including 10-100 mg/kg concentration of co-trimoxazole antibiotic. The vermicomposting seems to be an effective method for reducing fecal coliforms and parasites in cow manure. As well, co-trimoxazole in common concentration could not have any effects on the ability of earthworms. At the end of the vermicomposting, all parameters were placed within the ICS (National) - Grade 1.

Association of greenspace exposure with telomere length in preschool children

Exposure to greenspace has been associated with a wide range of health benefits; however, the available evidence on the association of this exposure with telomere length (TL), an early marker of ageing, is still scarce. We investigated the association of greenspace exposure with TL in a sample of 200 preschool children (aged 5-7 years) residing in Sabzevar, Iran (2017). We comprehensively characterized different aspects of greenspace exposure encompassing residential, kindergarten, and total (including both residential and kindergarten) surrounding greenspace (using satellite-derived Normalized Difference Vegetation Index), residential and kindergarten distance to green spaces, time spent in private gardens and public green spaces, and the number of plant pots at home. Relative leukocyte TL (LTL) in blood samples of the study participants was measured using quantitative polymerase chain reaction (qPCR). We applied mixed effects linear regression models with kindergarten and qPCR plate as random effects, to estimate the association of indicators of greenspace exposure (one at a time) with LTL, controlled for relevant covariates. We observed an inverse association between distance from home and kindergarten to green spaces larger than 5000 m² and LTL. Moreover, higher total surrounding greenspace at 300m and 500m buffers and higher surrounding greenspace at 300m buffer around kindergarten and home were associated with longer LTL. Furthermore, longer time spent (h/week) in the public green spaces was associated with longer LTL. Our findings for residential and kindergarten distance to any green space (regardless of the size), residential surrounding greenspace at 100m and 500m buffers, kindergarten surrounding greenspace at 100m buffer, time spent in private gardens (h/week) and the number of plant pots at home were not conclusive. Our findings were generally suggestive for a positive association between greenspace exposure and LTL in preschool children. More studies are needed to confirm these findings in other settings with different climates and populations.

Associations between climatic parameters and the human salmonellosis in Yazd province, Iran

Salmonella is one of the most common causes of foodborne disease outbreaks in developing countries. Climatic factors such as temperature, rainfall, and relative humidity can directly increase the growth and spread of these pathogens. Therefore, the aim of this study was to investigate long-term temporal trends and seasonal patterns of Salmonella infections as well as evaluating the effects of demographic and climatic factors on the infection incidence in Yazd province, Iran during 2012-2015. The incidence of Salmonella infections was highest among patients with the age group of ≤5 years and peaked in summer, especially during June. Contrary to expectations, no significant associations were seen between the average monthly temperature, rainfall or humidity and incidence rate (IR) of salmonellosis. Interestingly, atmospheric dust hovering was significantly associated with an increased risk of salmonellosis. Transmission pathways of Salmonella spp. in communities should be considered as a complex ecological process that animal reservoirs, socio-economic factors, and lifestyle behaviors need to be addressed in future studies.

Association of exposure to air pollution and telomere length in preschool children

Exposure to air pollution is associated with adverse health effects; however, the available evidence of its association with telomere length (TL), an early marker of ageing, in children is still scarce with no study available for preschool children. This study aimed to investigate the association of exposure to air pollution and traffic indicators at home and kindergarten with relative leukocyte TL (LTL) in preschool children. This cross-sectional study included 200 preschool children (5-7 years old) recruited from 27 kindergartens in Sabzevar, Iran (2017). Outdoor annual average levels PM₁, PM_2.5, and PM₁₀ at residential address and kindergartens were estimated applying land use regression (LUR) models. Moreover, indoor levels of PMs at kindergartens were measured for four days in each season resulting in a total of 16 days of measurements for each kindergarten. Total streets length in different buffers and distance to major road were calculated as traffic indicators at residential address and kindergartens. We applied quantitative real-time polymerase chain reaction (qRT-PCR) to measure relative LTL in blood samples obtained from children. Mixed linear regression models were developed with qPCR plate and kindergarten as random effects, to estimate association of each pollutant and traffic indicator with LTL, controlled for relevant covariates. Higher concentrations of outdoor PM₁, PM_2.5, and PM₁₀, at home and kindergartens were associated with shorter relative LTL. Similarly, increase in indoor PM_2.5 concentrations at kindergartens was associated with shorter relative LTL (β = -0.18, 95% CI: -0.36, -0.01, P-value < 0.01). Moreover, higher total street length in 100 m buffer around residence and lower residential distance to major roads were associated with shorter relative LTL (β = -0.25, 95% CI: -0.37, -0.13, P-value < 0.01, and 0.32, 95% CI: 0.20, 0.44, P-value < 0.01, respectively). Overall, our study suggested that higher exposure to air pollution and traffic at kindergarten and residential home were associated with shorter relative LTL in preschool children.

Dynamic assessment of economic and environmental performance index and generation, composition, environmental and human health risks of hospital solid waste in developing countries; A state of the art of review

Many studies have been conducted on hospital solid waste management (HSWM) throughout the world, especially developing countries. This interdisciplinary study aims to summarize the available knowledge on the health and environmental risks of hospital solid waste (HSW) and also, develop a dynamic associational assessment among hospital solid waste generation rate (HSWGR), hospital solid waste composition (HSWC), gross domestic product (GDP) per capita, and environmental performance index (EPI) in some developing countries for the first time. The results of this study showed that researchers from India, China, Pakistan, Brazil, and Iran had found more evidence about the health, economic, and environmental issues in HSW than the other developing countries. The literature showed that the highest and lowest reported HSWGR (in national average level) belonged to Ethiopia (6.03) and India (0.24) kg bed ^-1 day^-1, respectively. It has also been shown that all studied countries except Serbia, have higher levels of hazardous waste in their HSWC, based on the WHO's standard. Furthermore, the quantity and quality of HSW in developing countries depend on the service provided by the hospital, type of hospital, HSWM system, and the level of regional economic and culture. The association analysis showed that the EPI and GDP per capita of developing countries were significantly (p-value <0.05) associated with HSWGR, non-hazardous HSW, and hazardous HSW by the Spearman coefficients equal to 0.389, 0.118, -0.118, and 0.122, 0.216, and -0.346, respectively. However, it can be concluded that GDP per capita and EPI have a weak correlation with hazardous HSW and non-hazardous HSW. Moreover, HSW has many hazardous health and environmental risks such as dioxin and furan, that must be controlled and managed through implementing programs and policies based on sustainable development. As a final point, we believed that the present study can be considered to be a guide for future studies on HSWM in developing countries.

Developing a system dynamics model for prediction of phosphorus in facultative stabilization ponds

System dynamics is considered as a computer-aided approach to policy analysis and design. It includes the response and reaction of a system to external shocks. In the present research, following the sampling and testing phases, a system dynamics model was developed for modeling of phosphorus in facultative stabilization ponds. First, the scheme of soluble reactive phosphorous stock, its specifications and parameters were determined and created in the VenSim PLE 7.1 software. Then, mathematical relations were determined for each process. Finally, the model was calibrated and verified based on the data from the Yazd facultative ponds, Iran. Sensitivity analysis showed that the most important factors affecting phosphorus concentration in the ponds are the phosphorus settling rate, losses caused by algal respiration and excretion, while the losses caused by herbivorous zooplanktons, hydrolysis rate of inorganic carbon, and ratio of phosphorus to chlorophyll-a had the least importance. Results showed that, algal growth rate and phosphorus settling rate were important factors in phosphorus removal. Hence, with appropriate retention time in the pond, it can be managed more properly. The ratio of phosphorus to algae had less importance in the model. The ratio of carbon to phosphorus and rate of respiration of carnivorous zooplanktons did not affect the phosphorus concentration. It is recommended that this model can be used for pond management and overall assessment of facultative ponds.

Studies on influence of process parameters on simultaneous biodegradation of atrazine and nutrients in aquatic environments by a membrane photobioreactor

A Lab scale algal-bacterial membrane photobioreactor (MPBR) was designed and operated under 12-h light and 12-h dark conditions with a light intensity of 8000lx, in order to investigate the effects of initial concentrations of atrazine, carbon concentration, and hydraulic retention time on the ability of this photobioreactor in simultaneous removal of atrazine and nutrients in the continuous mode. The removal efficiencies of atrazine (ATZ), chemical oxygen demand (COD), phosphorus (PO₄^3--P) and nitrogen (NOx) in optimum condition was more than 95%, 99%, 98% and 97% when the maximum removal rates were 9.5 × 10^-3, 99.231, 11.773 and 7.762mg/L-day, respectively. Results showed that the quality of the effluent was reduced by the increase of atrazine concentration. The outcomes on the hydraulic and toxic shocks indicated that the system has a relatively good resistance to the shocks and can return to the stable conditions. Microalgae showed a great deal of interest and capability in cultivating and attaching to the surface of the membrane and bioreactor, and the total biomass accumulated in the system was greater than 6g/L. The kinetic coefficients of atrazine removal were also studied using various kinetic models. The maximum atrazine removal rate was determined by the modified Stover-Kincannon model. The results approved the ability of the MPBR reactor in wastewater treatment and microalgae cultivation and growth. The decline of atrazine concentration in this system could be attributed to the algal-bacterial symbiosis and co-metabolism process. Accordingly, the MPBR reactor is a practical, simple, economical and therefore suitable process for simultaneous biodegradation of chlorinated organic compounds and nutrients removal from aquatic environments.

Designing and modeling of a novel electrolysis reactor using porous cathode to produce H2O2 as an oxidant

The entry of toxic organic pollutants and resistant to biodegradation has increased the concern about human health. The use of advanced oxidation (AO) processes to degrade these pollutants has been developing. One of the AO processes is based on the use of hydrogen peroxide in removing resistant organic pollutants.

This study aimed to develop a new reactor capable of producing H₂O₂ in the solution. Therefore, a porous electrode made of stainless steel with the capability of air injection in the electrode center was used. The 30 cm rod graphite electrodes were also used as an anode electrode in a 4000 ml reactor. The effects of variables, including current density (30–40 mA/cm²), time (10–30 min), and electrolyte concentration (12–17 mM/L) on the amount of H₂O₂ production were evaluated by Box behenken design under response surface methodology using Design expert software. The results of this study showed that H₂O₂ can be produced at the electrode surface of porous cathode under optimal conditions of 36 mA/cm² current density, 16 mM/l electrolyte concentration, in 23 min, and in the amount of 34 ppm. Using a porous cathode electrode causes the maximum contact among the solution, water, and air, and increases the production of H₂O₂.

The release of resistant organic compounds to the waste water is a serious problem to the environment. By the application of the Electro-oxidation (EO)reactor with the ability to produce H₂O₂, this issue is resolved. Furthermore, this technique is applied for non-selective degradation of the toxic organic compounds.

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The electro-oxidation process is a useful method for destruction of persistent organic matter from wastewater.

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Due to use of porous cathode in this method, contact between the electrode and the sewage is at its maximum level which increases the efficiency and speed of sewage treatment.

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This method can produce H₂O₂ as a high potential oxidant that can reduce persistent organic properties of sewage and make the wastewater suitable for biological treatment.

Evaluation of Emergency Nurses’ Knowledge and Performance about Hospital Triage

Background and Objectives: By knowing the level of knowledge of triage nurses, we will be capable of making the right decision about allocating suitable resources for enriching the quality of the emergency department. So, the objective of our study is to evaluate triage knowledge and performance of emergency nurses in Yazd province of Iran. Materials and Methods: This was a cross-sectional study. The sampling was performed from all nurses responsible for triage in emergency departments of 8 educational hospitals of Yazd University of Medical Sciences were included for our sampling in the study. Data collection was done using a questionnaire whose validity and reliability have already been approved. After evaluating all the questionnaires, 84 of them were completed, and others were excluded from the study. Data were analyzed by descriptive and inferential statistics using the SPSS version 22 software. Results: According to statistical analysis results, there was no significant relationship between the knowledge score, performance and total score with demographic characteristics. Moreover, there was no significant relationship between educational courses, work experience and work shift with knowledge, performance and total score. Although female nurses’ scores in knowledge and performance areas was higher than male scores, the differences were not statistically significant. Conclusion: The level of knowledge of the nurses employed in the emergency departments of Shahid Sadoughi University of medical sciences in Yazd is moderate in terms of triage. However, the performance of nurses working in the emergency departments of the aforementioned centers is higher than average. It is concluded that there is an immediate need to reconsider nurses triage education and improve the triage knowledge and performance among nurses.

Meteorological correlates and AirQ+ health risk assessment of ambient fine particulate matter in Tehran, Iran

There are few studies in the world that have been evaluated the mortality due to exposure to particulate matter smaller than 2.5 µm by AirQ+ software. Therefore, the study aimed to correlate between fine particulate matter (PM2.5) and meteorological variables and estimate all-cause annual mortality and mortality from cerebrovascular disease (stroke), ischemic heart disease (IHD), acute lower respiratory infection (ALRI), lung cancer (LC), chronic obstructive pulmonary disease (COPD) attributed to long-term exposure to ambient PM2.5 in Tehran from March 2017 to March 2018 using the WHO AirQ+ software. Data related to air quality, meteorological condition, population and the baseline incidence rates of health endpoints in Tehran were gathered from government agencies. The association between the PM2.5 concentrations and meteorological variables in the period of study were assessed by correlation analysis. The results of correlation analysis showed a weak positive correlation between PM2.5 concentrations and average monthly temperature (r = 0.42, P < 0.05) and average monthly humidity (r = 0.37, P < 0.05) in Tehran. The quantitative risk assessment related to all-cause annual mortality, the mortality of IHD, stroke, COPD, LC and ALRI were estimated 6710, 3797, 1145, 172, 135 and 27 cases, respectively. The results of regression association analysis between PM_2.5 and the number of recorded deaths was showed that with an increase of one microgram per cubic meter of PM_2.5, it is expected that about 27 cases will be added to air pollution mortality in Tehran.

Environmental and behavioral determinants affecting the association of airway macrophages carbon load with distance to major roads and traffic density

Biomarkers are promising indicators to evaluate human exposure to air pollutants and to predict the health outcomes. Area of Airway macrophages that is occupied by Black Carbon could be used as a biomarker of personal long term exposure to traffic related air pollution. Association of airway macrophages carbon load with weighted average distance and environmental and subject-specific behavior are considered in this study. Sputum samples were taken from 160 healthy adult women and airway macrophages carbon load (AMCL) were determined in 93 subjects, which represent a success rate of 62% in sputum induction. Nearest distance of the subjects to major roads and average weighted distance were calculated for each subject. A questionnaire was field according to general and behavioral characteristics of the participants. There was not any significant difference (P-value >0.05) between induced and non-induced subjects. Subjects with indoor kitchen without separation wall, passive smokers and those with longer presence time in high traffic streets showed higher carbon area. Weighted average distance had a better association (β = -0.186, 95%CI: -0.139, -0.230, P-value = 0.00) with AMCL than nearest distance to major roads (β = -0.155, 95%CI: -0.109, -0.201, P-value = 0.19). Association of Weighted average distance with AMCL was interrupted in subjects with a garage connected to house environment, those with IK kitchen, those with a hood above the stove and passive smokers. The findings indicated that more generation and distribution of indoor air pollutants can completely enhance the internal exposure and indoor pollution has the same importance as outdoor pollution.

Air pollution and telomere length in adults: A systematic review and meta-analysis of observational studies

Telomere length (TL) has been suggested to be a surrogate for cellular ageing, and a record of cumulative inflammation and oxidative stress over life. An emerging body of evidence has associated exposure to air pollution to changes in TL. To date there is no available systematic review of literature on this association. We aimed to systematically review and conduct meta-analysis of published studies on the relationship between air pollution and TL in adults. Electronic databases were systematically searched for available English language studies on the association between air pollution and TL published up to 1 July 2018. Meta-analyses were conducted following MOOSE guidelines. The heterogeneity in the reported associations was assessed using Cochran's Q test and quantified as I² index. Publication bias was assessed using Egger's regression. Our search identified 19 eligible studies including 11 retrospective and eight prospective studies of which, four had excellent quality, ten had good quality and five had fair quality. Meta-analysis result of two studies on long-term exposure to PM_2.5 showed an inverse association between these exposures and TL (for 5 μg/m³ PM_2.5-0.03 95% CI; -0.05, -0.01). Meta-analysis of short-term exposure to PM_2.5 with three studies and Polychlorinated Biphenyls (PCBs) with two studies revealed a direct association between these exposures and TL (0.03 95% CI; 0.02, 0.04 and 0.10 95% CI; 0.06, 0.15 respectively). No statistically significant relationship between exposure to PM₁₀ and polycyclic aromatic hydrocarbons (PAHs) exposure and TL were observed. We observed suggestive evidence for associations between air pollution and TL with potentially different direction of associations for short- and long-term exposures.

Quantitative and qualitative analysis of construction and demolition waste in Yazd city, Iran

Construction and demolition waste is the major category of municipal solid waste that is important due to high volume and mass produced. Therefore, this study aims to analyze the quantitative and qualitative of construction and demolition waste in Yazd. This descriptive cross-sectional study was conducted on a waste disposal site in Yazd in 2017–2018. sampling of the construction and demolition waste disposal site was performed for 12 months (Jul 2017 to Jul 2018). According to a researcher-made checklist, data on the weight, the density and volume of these wastes were collected. The descriptive statistics tests of data were processed in Excel software. 53,445 t of waste are annually generated in Yazd that the amount of cement and concrete, bricks, tile and ceramic (TC), ferrous metals, non-ferrous metals, glass, plastic, wood, and are approximately 38%, 20%, 14%, 11%, 6%, 5%, 3%, and 3%, respectively. With regards to the high volume of waste generated and a remarkable part of the recyclable waste, urban planners should pay attention to the implementation of waste reduction and recycling programs.

Bisacodyl removal from contaminated solution by synthesized mesoporous silica using experimental design method

Most of the medicinal compounds are entered no change into municipal wastewater and more than 90% of it remains in the wastewater. Mesoporous silica is known as thermally stable materials with controllable porosity and morphology. It is specified that these materials possess external and internal surfaces that can be selectively adsorbed the various compounds. In the present study, the synthesized mesoporous silica was studied to remove bisacodyl from polluted solutions. Mesoporous silica was synthesized by simple chemical method from tetraethylorthosilicate, ethanol (C2H5OH) and deionized water at 70 °C temperature. Characteristic of synthesized mesoporous silica was investigated by scanning electron microscopy. The effective parameters such as contact time, pH, adsorbate dose, and initial bisacodyl concentration were optimized for bisacodyl removal using 27 batch adsorption experiments according to design of experiment. The residual bisacodyl concentration was measured by UV-Vis spectrometer at the maximum wavelength of 580 nm. The statistical test and linear regression model were used by MINITAB 16 software for investigation of the main and interaction effects of each factor in the adsorption process. The ANOVA result showed 84% of bisacodyl was removed by synthesized mesoporous silica at optimum condition. The result of regression (R2 > 0.99) indicated that the adsorption process followed the Langmuir isotherm and second order kinetic at optimum conditions. The mesoporous silica is an efficient adsorbent for removing of bisacodyl from the polluted solutions so that it can be used for refining wastewaters containing medical compounds such as bisacodyl.

Efficient photocatalytic oxidation of arsenite from contaminated water by Fe2O3-Mn2O3 nanocomposite under UVA radiation and process optimization with experimental design

The efficiency of photocatalytic oxidation process in arsenite (As(III)) removal from contaminated water by a new Fe₂O₃-Mn₂O₃ nanocomposite under UV_A radiation was investigated. The effect of nanocomposite dosage, pH and initial As(III) concentration on the photocatalytic oxidation of As(III) were studied by experimental design. The synthesized nanocomposite had a uniform and spherical morphological structure and contained 49.83% of Fe₂O₃ and 29.36% of Mn₂O₃. Based on the experimental design model, in photocatalytic oxidation process, the effect of pH was higher than other parameters. At nanocomposite concentrations of more than 12 mg L^-1, pH 4 to 6 and oxidation time of 30 min, photocatalytic oxidation efficiency was more than 95% for initial As(III) concentration of less than 500 μg L^-1. By decreasing pH and increasing the nanocomposite concentration, the photocatalytic oxidation efficiency was increased. Furthermore, by increasing the oxidation time from 10 to 240 min, in addition to oxidation of As(III) to arsenate (As(V)), the residual As(V) was adsorbed on the Fe₂O₃-Mn₂O₃ nanocomposite and total As concentration was decreased. Therefore, Fe₂O₃-Mn₂O₃ nanocomposite as a bimetal oxide, at low doses and short time, can enhance and improve the efficiency of the photocatalytic oxidation and adsorption of As(III) from contaminated water resources. Furthermore, the energy and material costs of the UV_A/Fe₂O₃-Mn₂O₃ system for photocatalytic oxidation of 1  mg L^-1 As(III) in the 1 L laboratory scale reactor was 0.0051 €.

Environmental determinants of polycyclic aromatic hydrocarbons exposure at home, at kindergartens and during a commute

The aim of this study was to assess the potential health risk of exposure to polycyclic aromatic hydrocarbons (PAHs) at home and kindergarten for pre-school children. The urine samples were taken from 200 pre-school children aged 5-7 years and analyzed for 1-OHP as a biomarker of PAHs. Mixed effect models were applied to investigate the association between effective environmental parameters (mode of transport, distance to major roads, traffic density, greenness, tobacco exposure, home ventilation, and grill foods) and urinary 1-OHP levels. A Monte-Carlo simulation technique was applied to calculate the risk of exposure to PAHs and to check the uncertainty of input variables and the sensitivity of the estimated risk. The median and inter quartile range (IQR) of 1-OHP was 257 (188.5) ng L^-1. There was a positive significant association between distance from the kindergartens to the green space with surface area ≥5000 m² and 1-OHP concentration (β = 0.844, 95% CI: 0.223, 1.46, P-value = 0.009). Also, urinary 1-OHP was found to be inversely associated with the time the window was open at the home (β = -12.56, 95% CI: -23.52, -1.596, P-value = 0.025) and normalized difference vegetation index (NDVI) in a 100 m buffer around the homes. The mean (9.76 E-3) and 95th percentile (3.28 E-2) of the hazard quotient (HQ) indicated that the concentration of urinary 1-OHP is at a safe level for the target population (HQ < 1). According to the sensitivity analysis results, the concentration of 1-OHP is the most influential variable in the estimated risk. Our findings indicated that the proximity of homes and kindergartens to green space areas and their remoteness from the main streets and heavy traffic areas are associated with reduced exposure to PAHs.

Modeling photocatalytic degradation of diazinon from aqueous solutions and effluent toxicity risk assessment using Escherichia coli LMG 15862

In this study, modeling and degradation of diazinon from contaminated water by advanced oxidation process together with a new test for effluent bioassay using E. coli were investigated. The experiments were designed based on response surface methodology. Nanoparticles (NPs) were synthesized using the sol–gel method. The shape characteristics and specifications of elements in the nanoparticles were characterized using scanning electron microscope and energy dispersive X-ray, respectively. Diazinon was measured using high performance liquid chromatography device and by-products due to its decomposition were identified by gas chromatography-mass (GC–MS). In the present study, effluent bioassay tests were conducted by defining the rate of dehydrogenase enzyme reducing alamar blue method. According to statistical analyses (R² = 0.986), the optimized values for pH, dose of NPs, and contact time were found to be 6.75, 775 mg/L, and 65 min, respectively. At these conditions, 96.06% of the diazinon was removed. Four main by-products, diazoxon, 7-methyl-3-octyne, 2-isopropyl-6-methyl-4pyrimidinol and diethyl phosphonate were detected. According to the alamar blue reducing (ABR) test, 50% effective concentration, no observed effect concentration, and 100% effective concentration (EC₁₀₀) for the mortality rate of E. coli were obtained as 2.275, 0.839, and 4.430 mg/L, respectively. Based on the results obtained, it was found that mentioned process was high efficiency in removing diazinon, and also a significant relationship between toxicity assessment tests were obtained (P < 0.05).

Correlation between drinking water fluoride and TSH hormone by ANNs and ANFIS

Background

Artificial neural networks (ANNs) and adaptive neural-fuzzy Inference system (ANFIS) are the best solutions to finding the correlation between some water parameters and human hormones. The correlation between thyroid stimulating hormone (TSH) and drinking water fluoride studied by ANN_S and ANFIS models in Yazd city.

Method

In this study, eighty people with thyroid gland disorder and 213 healthy people invited. Their thyroid hormones and fluoride drinking water analyzed.

Results

The result of ANFIS showed R² = 0.81 for test and R² = 0.85 for train in all cases and controls data. This results were R² = 0.73 and R² = 0.81 for ANNs respectively.

Conclusion

This models can be used as an alternative for show correlation between Drinking Water Fluoride and TSH Hormone and R² = 0.85 gained from ANFIS was the best.