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In this study, seven compounds of environmental and health concern were treated by electrooxidation to determine their removal efficiencies from domestic wastewater. A batch type lab-scale reactor was used for the treatment process, and the analytes studied included two obsolete pesticides, two alkylphenols, two hormones, and bisphenol A. Titanium oxide and graphite electrodes were used as anode and cathode, respectively. Parameters of the electrooxidation process including pH of wastewater, ionic strength, applied current and treatment period were optimized by the univariate approach to maximize the removal efficiency of the analytes from wastewater. The optimum conditions were determined as nonadjusted pH of wastewater, 1.5 A current, 15 min treatment period and 5.0 g/L sodium chloride. Dispersive liquid-liquid microextraction was used to preconcentrate analytes before and after treatment in order to calculate the removal efficiency of analytes. The removal efficiency obtained under the optimum conditions was satisfactory for all seven analytes at different influent concentrations.

Rationale: Pesticides are a group of micropollutants that persist for a long time in the environment and pose threats to life. Much effort has been devoted to developing pre-concentration methods capable of producing samples suitable for the detection of pesticides. However, better methods are still required to detect these compounds when they are present in trace concentrations in soils., Method: Spray-assisted fine-droplet-formation-based liquid-phase microextraction was used to prepare soil samples containing three different pesticides, fenpiclonil, nitrofen and fenoxaprop-ethyl, for subsequent analysis by gas chromatography/mass spectrometry (GC/MS). A spraying apparatus was used for the dispersion of the extraction solvent into the sample/standard solution to improve the extraction efficiency. Optimization studies were performed to lower the detection limits of these analytes and the results obtained by the application of the newly developed system were compared with those obtained using the conventional GC/MS method., Results: A calibration curve over the range 5.0-100 μg L -1 was obtained under the optimal conditions. The limits of detection and quantification were 1.56-1.80 μg L -1 and 5.21-5.98 μg L -1 , respectively. The enhancements in detection ability over the conventional method for the three tested pesticides were 188.01, 176.96 and 517.14 for fenpiclonil, nitrofen and fenoxaprop-ethyl, respectively Recovery studies performed in soil samples were satisfactory reflecting accurate applicability of the developed method., Conclusions: The developed microextraction method is a time-saving and simple version of the traditional dispersive liquid-liquid microextraction method that also reduces the use of dispersive solvents., (© 2020 John Wiley & Sons, Ltd.)

Background: Although the exact pathophysiology of functional gastrointestinal diseases remains unclear, numerous etiologies have been blamed, including visceral hypersensitivity, gastrointestinal motility disorders, psychological factors, intestinal mucosal inflammation, intestinal microbiota, and post-infectious syndromes. In the present study, we aimed to evaluate pancreatic insufficient patients diagnosed with functional abdominal pain-not otherwise specified (FAP-NOS) according to Rome IV criteria., Methods: The study included a total of 110 patients aged 4-17 years who were diagnosed with FAP-NOS according to Rome IV criteria. The control group consisted of 80 patients with no gastrointestinal disorders and chronic diseases. Glucose, amylase, lipase, pancreatic amylase, immunoreactive trypsinogen (IRT) and fecal elastase (FE-1) levels were examined for each patient., Results: No significant difference was found between the two groups with regard to lipase, pancreatic amylase, IRT, and serum glucose levels. However, the amylase levels were significantly higher and the FE-1 levels were significantly lower in the study group compared to the control group (p=0.007 and p < 0.001). The cut-off value detected in in ROC analysis for the diagnostic value of FE-1 in predicting FAP-NOS was found to be 140.107 μg/g. Based on this value, the sensitivity, specificity, PPV, and NPV of FE-1 were 82.1%, 66.2%, 77%, 73%, respectively. Accordingly, the likelihood of FE-1 in providing a positive value in patients with FAP-NOS was almost 9 times higher than in individuals without FAP-NOS., Conclusions: FE-1 levels were significantly lower in children diagnosed with FAP-NOS and we consider that this difference could be attributed to malabsorption secondary to dysbiosis as there is not enough data.

Membrane bioreactors (MBRs) are rapidly developing systems widely used for the treatment of municipal and industrial wastewater prior to their discharge into the environment. Membrane fouling is the most important challenge in MBRs, because it negatively affects membrane performance, resulting in low permeate flux, higher transmembrane pressure and frequent membrane cleaning/replacement. In this study, the effect of tea and coffee on sludge characteristics, membrane fouling and the bacterial signalling molecule N-butyryl-l-homoserine lactone ( C4-HSL) in a membrane bioreactor system were investigated. For this purpose, four different continuously operated membrane bioreactors, treating synthetic domestic wastewater and dairy wastewater were operated in parallel under the same conditions. The results indicated that the soluble microbial products (SMP) and the extracellular polymeric substances (EPS) in the reactors showed similar trends for both synthetic domestic and dairy wastewater, where protein levels were higher than carbohydrate levels. Other parameters such as floc size, zeta potential, hydrophobicity, sludge volume index and capillary suction time were also analysed prior to and after the addition of coffee and tea. Analysis of the wastewater samples by GC-MS revealed that coffee and tea significantly enhance the extraction efficiency of C4-HSL. The results obtained in this study can serve as a good basis for further research.

This study presents the use of Quick Easy Cheap Efficient Rugged and Safe (QuEChERS) as an effective sample cleaning procedure and switchable solvent liquid phase microextraction (SS-LPME) as a preconcentration tool for the determination of fenazaquin by gas chromatography mass spectrometry (GC-MS) at ultratrace levels. After a thorough optimization process, 0.50 mL of switchable solvent, 1.5 mL of 1.0 M sodium hydroxide, and 15 s of vortexing were determined as optimum conditions of the SS-LPME method. The limit of detection (LOD) and limit of quantitation (LOQ) determined using the optimum method (SS-LPME/GC-MS) were 0.05 and 0.18 ng/mL, respectively. Compared with direct GC-MS determination of fenazaquin, the optimum method yielded about 800-fold enhancement in detection power of GC-MS. The method was applied to lake, irrigation canal, well, and wastewater samples. In order to test the method's applicability on fresh tomato samples, a QuEChERS method was used before applying the SS-LPME method. Matrix-matched calibration standards were used to enhance the accuracy of fenazaquin quantification in spiked tomato samples to obtain recovery results close to 100%.

Determination of lead at trace levels was achieved by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) after the preconcentration with deep eutectic solvent-based liquid phase microextraction (DES-LPME). A green solvent was used to extract lead from the aqueous solution. Parameters affecting the extraction efficiency and determination were optimized in the aim to lower the detection limit. Under the optimum experimental and instrumental conditions, the proposed method exhibited a linear range between 50 and 1000 µg L -1 , and the limits of detection and quantitation (LOD and LOQ) were found to be 8.7 and 29.0 μg L -1 , respectively. The detection power was improved by 48 times using DES-LPME-SQT-FAAS method with respect to conventional FAAS system. Recovery studies were carried out in raw milk samples to check the accuracy and the applicability of the developed method and the percent recoveries obtained were between 102.5 and 103.2% for the spiked raw milk samples., (Copyright © 2019 Elsevier Ltd. All rights reserved.)