Removal of benzophenone-4 via chlorination and advanced oxidation processes in aqueous solution: kinetics, by-product identification, and mechanistic studies.

Benzophenone-4 (BP-4) is one of the UV filters widely used in personal care products (PCPs). BP-4 has been identified as an emergent contaminant detected in influent and effluent of wastewater treatment plants (WWTPs) at high concentrations showing that conventional treatment is unable to remove it, subsequently, the presence of BP-4 in surface water is inevitable. In this study, we focus on the degradation of this compound by chlorine, and we report the efficiency of its removal from water by applying two advanced oxidation processes UV/TiO and UV/HO aiming to achieve a superior mineralization result.

Occurence of antimicrobial residues in milk and labneh consumed in Lebanon.

Antimicrobials are administered in livestock for different uses leading to milk contamination and several undesirable effects. Because there is a lack of surveillance of antimicrobial residues (AMRs) in milk and dairy products in Lebanon, this study aims to determine the occurrence of AMRs in 90 Lebanese samples of milk and labneh (concentrated yoghurt). Multi-residue screening methods with suitable sample preparations were applied to detect 71 AMRs in milk and labneh, respectively, using LC-MS/MS.

Degradation of azoxystrobin, methoxyfenozide, and propyzamide by ultrasound treatment.

Ultrasound as a green and efficient process gains special attention in wastewater treatment. The ultrasound-assisted degradation of azoxystrobin, methoxyfenozide, and propyzamide as widely used pesticides for vine treatment was investigated. A wide range of ultrasonic power (40 to 140 W) and a single frequency (20 kHz) were applied.

Is There Correlation Between Aluminum-Based Food Consumption and Plasma Level in Pregnant Women?

To explore the correlation of AL-based food consumption, known to have negative impact on health, and Al plasma levels with pregnancy status. A cross-sectional study was conducted on 75 participants, including 50 pregnant women. Al plasma levels were analyzed by ET-AAS.

Chromatographic methods for the determination of a broad spectrum of UV filters in swimming pool water.

This paper describes an analytical approach based on solid-phase extraction (SPE) followed by analysis using liquid and gas chromatography coupled to mass spectrometry detectors for a determination of 18 organic UV filters from water samples. Extraction method parameters were optimized: 250 ml of water sample loaded on Chromabond C18 cartridges after adjustment to pH 4 and then eluted with acetonitrile. The mobile phase and the parameters of the mass spectrometer, as well as those of the ionization source, were tested to enhance detection sensitivity.

Evaluation of honey authenticity in Lebanon by analysis of carbon stable isotope ratio using elemental analyzer and liquid chromatography coupled to isotope ratio mass spectrometry.

Honey is one of the most valuable sweeteners consumed by humans all over the world. Consequently, it is often a target for adulteration through the addition of different sugar syrups during or after honey production, resulting in a reduction in its nutritive value. For the first time, this study analyzes honey samples of various botanical species collected from different Lebanese regions using element analyzer (EA) and liquid chromatography (LC) coupled with isotope ratio mass spectrometry (IRMS).

Nutritional value of the Middle Eastern diet: analysis of total sugar, salt, and iron in Lebanese traditional dishes.

The expanding burden of diet-related non-communicable diseases in the Eastern Mediterranean Countries requires urgent public health vigilance and actions. This study aimed at establishing a database analysis of total sugar, salt and iron content in Lebanese foods, focusing on traditional dishes. The collection of food samples was done using stratified sampling techniques.

Aluminum exposure from food in the population of Lebanon.

Widely used for a variety of applications, levels of dietary aluminum (Al) have seen a perpetual rise in Lebanon, leading to noticeable effects upon the human body. This study aims to estimate the rates of Al contaminated food consumption and quantify the Al present in different dietary matrices, revealing the major contributors to Al exposure for the Lebanese population. A cross-sectional study was conducted using a customized, self-reported Electronic Food Frequency Questionnaire (E-FFQ) using Curve®, targeting individuals between the ages of 18 and 64 from different Lebanese regions, distributed proportionally.

Two-Player Game in a Complex Landscape: 26S Proteasome, PKA, and Intracellular Calcium Concentration Modulate Mammalian Sperm Capacitation by Creating an Integrated Dialogue-A Computational Analysis.

Recent experimental findings suggest the involvement of the 26S proteasome, the main protease active in eukaryotic cells, in the process that leads mammalian sperm to become fully fertile, so-called capacitation. Unfortunately, its role in male gametes signaling is still far from being completely understood. For this reason, here, we realized a computational model, based on network theory, with the aim of rebuilding and exploring its signaling cascade.

Antimicrobial residues survey by LC-MS in food-producing animals in Lebanon.

The treatment of animals with antimicrobial products may lead to the contamination of edible tissues by their residues, which may represent a risk to human health. Therefore, this study aimed to determine the level of antimicrobial residues in food-producing animals (chicken, beef, and milk) in Lebanon. A total of 310 samples were collected and analysed using an LC-MS/MS for the determination of 48 compounds belonging to different families in order to map their compliance according to the European Commission decision 2002/657/EC.

LC-MS/MS method for the determination of hormones: Validation, application and health risk assessment in various bovine matrices.

A new method, using liquid chromatography coupled to mass spectrometry (LC-MS/MS) for the detection of fourteen natural and synthetic hormones in muscles, was validated in other bovine matrices (liver, kidney, bile and hair) according to the Decision Commission 2002/657/EC. As result, this method demonstrates good linearity (R > 0.99) as well as accuracy with coefficients of variation for repeatability and reproducibility lower than 23%.

Pesticide residues in Lebanese apples and health risk assessment.

In Lebanon, apples are among the most consumed commodities; however, pesticide residues in apples have not been evaluated so far. Therefore, this study presents the occurrence of pesticide residues in apples produced in Lebanon during 2012-2016. A total of 212 samples were analysed for the presence of pesticides using the QuEChERS multi-residue extraction method, followed by GC-MS.

Aqueous chlorination of sulfamethazine and sulfamethoxypyridazine: Kinetics and transformation products identification.

Sulfonamides (SNs) are synthetic antimicrobial agents. These substances are continually introduced into the environment, and they may spread and maintain bacterial resistance in the different compartments. The chlorination of 2 SNs, namely, sulfamethazine (SMT) and sulfamethoxypyridazine (SMP), was investigated to study their reactivity with chlorine at typical concentrations for water treatment conditions.

Transformation of sulfaquinoxaline by chlorine and UV light in water: kinetics and by-product identification.

Sulfaquinoxaline (SQX) is an antimicrobial of the sulfonamide class, frequently detected at low levels in drinking and surface water as organic micropollutant. The main goal of the present study is the evaluation of SQX reactivity during chlorination and UV irradiations which are two processes mainly used in water treatment plants. The SQX transformation by chlorination and UV lights (254 nm) was investigated in purified water at common conditions used for water disinfection (pH = 7.

Photodegradation of novel oral anticoagulants under sunlight irradiation in aqueous matrices.

Kinetics of photodegradation of novel oral anticoagulants dabigatran, rivaroxaban, and apixaban were studied under simulated solar light irradiation in purified, mineral, and river waters. Dabigatran and rivaroxaban underwent direct photolysis with polychromatic quantum yields of 2.2 × 10 and 4.

Impact of ion-pairs for the determination of multiclass antimicrobials residues in honey by LC-MS/MS.

This study examines the behaviour of volatile perfluorinated carboxylic acids used as ion-pairing reagents for the separation of multiclass antimicrobial residues in honey (tetracyclines, sulphonamides, macrolides, and aminoglycosides). Heptafluorobutanoic acid and pentafluoropentanoic acid were compared as mobile phase additives at concentrations of 0-20 mmol.L using reversed-phase chromatography.

Innovative SPE-LC-MS/MS technique for the assessment of 63 pharmaceuticals and the detection of antibiotic-resistant-bacteria: A case study natural water sources in Lebanon.

A powerful analytical method for simultaneous determination of 63 pharmaceuticals and some metabolites in aqueous samples has been developed. The list of compounds amenable to the methods includes different therapeutic classes belonging to antibiotics, stimulants, antidepressants, mucolytics, and antiparasites. The method involves concentration and clean up by an offline solid phase extraction SPE followed by liquid chromatography coupled to tandem mass spectrometry (LC-ESI-MS/MS).

Design for the transfer of a validated liquid chromatography/tandem mass spectrometry analytical method for the determination of antimicrobial residues in honey from low-resolution to high-resolution mass spectrometry.

Rationale: This paper investigates the validity of the transfer of a liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the determination of veterinary medicinal products in honey and compares it with an LC/linear ion trap/Orbitrap mass spectrometry method. A descriptive statistical approach was used in order to assess whether such a transfer would succeed or fail. This approach is based on the simultaneous evaluation of the trueness and of the intermediate precision for each compound at a 95% interval of confidence of both analytical techniques.

Oxidation of danofloxacin by free chlorine-kinetic study, structural identification of by-products by LC-MS/MS and potential toxicity of by-products using in silico test.

Unlabelled: In this study, we aimed to investigate the kinetics and the mechanism of reaction of the fluoroquinolone antibacterial danofloxacin (DANO) by free available chlorine (FAC) during water chlorination process. Kinetic study was thus performed at pH 7.2, 20 °C in the presence of an excess of total chlorine.

Development and validation of a multiclass method for the determination of antibiotic residues in honey using liquid chromatography-tandem mass spectrometry.

A new, simple and fast method was developed for the determination of multi-class antibiotic residues in honey (sulfonamides, tetracyclines, macrolides, lincosamides and aminoglycosides). Separation and determination were carried out by LC-MS/MS. During sample preparation, various parameters affecting extraction efficiency were examined, including the type of solvent, pH, efficiencies of cleavage of N-glycosidic linkages by hydrochloric acid, ultrasonic extraction and its duration compared with shaking, along with dispersive SPE clean-up.

Occurrence of pesticide residues in Lebanon's water resources.

Contamination of water sources by pesticides is one of the most critical environmental problems. The present work is designed to address the occurrence of 67 pesticides in the Lebanese waters. Chemical analysis was performed by a solid-phase extraction followed by a gas chromatography-mass spectrometry using programmed temperature vaporization injection.

Optimization of a solid-phase extraction method using centrifugation for the determination of 16 polycyclic aromatic hydrocarbons in water.

A fast and reliable method for the determination of polycyclic aromatic hydrocarbons (PAHs) in water samples by solid-phase extraction (SPE) using centrifugation has been developed and optimized. A silica-based C18 cartridge was used; parameters affecting the extraction procedure such as type and volume of the elution solvent, breakthrough volume of the percolated water sample, drying of the sorbent, and evaporation of the elute have been studied. The innovation of this work was the examination of the use of a centrifugation technique in both the drying and elution steps.