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/TiO2 and UV/H2O2 aiming to achieve a superior mineralization result. The study was performed in purified water (pH = 6.5, temperature = 25 °C) with an initial concentration of BP-4 similar to that detected in WWTPs (10 mg/L). The results showed that 76% of BP-4 was degraded after 80 min of reaction with chlorine leading to the formation of one by-product persistent in the solution. The oxidation by UV/TiO2 and UV/H2O2 led to a total removal of BP-4 and their generated by-products after 50 and 10 min of reactions, respectively. The kinetic study showed that BP-4 degradation by UV/H2O2 and UV/TiO2 followed pseudo-first-order reaction kinetics and the apparent rate constants (kapp) were determined to be 0.48 min-1 and 0.08 min-1, respectively. The degradation of BP-4 by chlorine followed first-order reaction kinetics with kapp = 0.02 min-1. The identification of by-product structures was performed using liquid chromatography with electrospray ionization and tandem mass spectrometry (MS/MS. The fragmentation of BP-4 and by-product ions at different collision energies allowed to propose the pathways of degradation and to predict the toxicity using a silico toxicity program which confirmed a higher toxicity of all generated by-products.

Identification and quantification of flavor compounds in smoked tuna fish based on GC-Orbitrap volatolomics approach.

Cold smoking enhances the appeal of fish products, offering consumers a smooth texture and a delicate smoky flavor. This study aims to explore variations in the volatile profile from different exposure times during cold smoking processing (light, moderate, and full-cure) in tune samples. An innovative untargeted analytical approach, headspace solid-phase microextraction combined with gas chromatography and a hybrid quadrupole-orbitrap mass analyzer, was employed to identify 86 volatiles associated with the cold smoking process. Most of these compounds, including phenols, furan derivates, aldehydes, cyclic ketones, and different aromatic species, were found to contribute to the smoke odor. The development of a QuEChERS-based extraction and clean-up method facilitated the quantification of 25 relevant smoky markers across all smoking degrees, revealing significant concentration differences after 15 h of smoking. This research sheds light on the dynamics of cold smoking impact and its on the flavor profile and safety quality of processed fish products.

Pre-Treatment of Swine Oviductal Epithelial Cells with Progesterone Increases the Sperm Fertilizing Ability in an IVF Model.

Mammalian spermatozoa are infertile immediately after ejaculation and need to undergo a functional modification, called capacitation, in order to acquire their fertilizing ability. Since oviductal epithelial cells (SOECs) and progesterone (P4) are two major modulators of capacitation, here we investigated their impact on sperm functionality by using an IVF swine model. To that, we treated SOECs with P4 at 10, 100, and 1000 ng/mL before the coincubation with spermatozoa, thus finding that P4 at 100 ng/mL does not interfere with the cytoskeleton dynamics nor the cells' doubling time, but it promotes the sperm capacitation by increasing the number of spermatozoa per polyspermic oocyte (p < 0.05). Moreover, we found that SOECs pre-treatment with P4 100 ng/mL is able to promote an increase in the sperm fertilizing ability, without needing the hormone addition at the time of fertilization. Our results are probably due to the downregulation in the expression of OVGP1, SPP1 and DMBT1 genes, confirming an increase in the dynamism of our system compared to the classic IVF protocols. The results obtained are intended to contribute to the development of more physiological and efficient IVF systems.

Hormones residues in bovine animals: Sampling, analysis and health risk assessment.

The use of hormones for breeding animal livestock has been banned since 1981 under the Council Directive 81/602/EC. So far, each country should monitor the use of anabolic hormones in animal production to protect the consumer's health against these unwanted residues. This paper presents the research results on steroid and non-steroid hormones residues carried out in Lebanon from 2018 to 2020. Using a newly developed and validated LC-MS/MS method, the detection and the quantification of hormones in bovine matrices were done. The targeted matrices were muscle, liver, kidney, and bile. A total of two-hundred and forty-seven samples were collected from different slaughterhouses located in six different cities in Lebanon. Interestingly, only four hormones were found: testosterone, progesterone, epitestosterone, and 6 propyl 2thiouracil. Based on the obtained data, the estimated daily intake, hazard quotient, and hazard index were calculated to evaluate an exposure assessment.

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. During method validation, the extracted target compounds showed good recoveries (> 68%) with acceptable values in terms of repeatability (RSDr) and reproducibility (RSDR), where relative standard deviations values were lower than 20%. The validated method was applied to 10 water samples collected from different swimming pools located in Lebanon from which eight UV filters among the eighteen targets compounds were detected at concentrations ranged between 1 and 2526 µg L-1. The most detected compounds were padimate-O (OD-PABA) and octocrylene (OCR). This study represents the first available data on the occurrence of UV filter residues in Lebanese swimming pool opening hence future perspectives and insights to evaluate their degradation by-products and their toxicity on human health and marine ecosystem.

Comparison of the toxicity of waters containing initially sulfaquinoxaline after photocatalytic treatment by TiO2 and polyaniline/TiO2.

This paper addresses the residual toxicity of waters after photocatalysis treatments. The initial waters contain 7 mg L-1 of sulfaquinoxaline (SQX) which is a sulfonamide antibiotic generally recorded inside the water. The contaminated waters are treated by photocatalytic degradation process with bare titania and titania covered with polyaniline (PANI) conducting polymer. The degradation of SQX is conducted at different pH in order to find the optimal condition to obtain SQX concentration relatively equal to zero in the shortest amount of time. This occurs for PANI/TiO2 at pH 12 and TiO2 at pH 4. Toxicity assays (concentration of biomass, pigmentation tests, and cells counting) are undertaken on the microalgae Chlorella vulgaris in order to evaluate the residual toxicity of the 2 treated waters. The toxicity results highlight that the water treated by PANI/TiO2 at pH 12 is the less toxic towards the algae cells. The water processed by bare titania at acidic pH displays unneglectable toxicity towards the algae cells which are larger than the toxicity of the original SQX solution.

Human Immune System Diseasome Networks and Female Oviductal Microenvironment: New Horizons to be Discovered.

Human hypofertility and infertility are two worldwide conditions experiencing nowadays an alarming increase due to a complex ensemble of events. The immune system has been suggested as one of the responsible for some of the etiopathogenic mechanisms involved in these conditions. To shed some light into the strong correlation between the reproductive and immune system, as can be inferred by the several and valuable manuscripts published to date, here we built a network using a useful bioinformatic tool (DisGeNET), in which the key genes involved in the sperm-oviduct interaction were linked. This constitutes an important event related with Human fertility since this interaction, and specially the spermatozoa, represents a not-self entity immunotolerated by the female. As a result, we discovered that some proteins involved in the sperm-oviduct interaction are implicated in several immune system diseases while, at the same time, some immune system diseases could interfere by using different pathways with the reproduction process. The data presented here could be of great importance to understand the involvement of the immune system in fertility reduction in Humans, setting the basis for potential immune therapeutic tools in the near future.

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. As a result, we found that the 26S proteasome is part of a signal transduction system that recognizes the bicarbonate ion as an input terminal and two intermediate layers of information processing. The first is under the control of the 26S proteasome and protein kinase A (PKA), which are strongly interconnected, while the latter depends on intracellular calcium concentrations. Both are active in modulating sperm function by influencing the protein phosphorylation pattern and then controlling several key events in sperm capacitation, such as membrane and cytoskeleton remodeling. Then, we found different clusters of molecules possibly involved in this pathway and connecting it to the immune system. In conclusion, this work adds a piece to the puzzle of protease and kinase crosstalk involved in the physiology of sperm cells.

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. Results show that 60% of the analysed samples were not contaminated by any residue, while 12% presented a concentration higher than the MRLs for tetracyclines, sulphonamides, quinolones, and macrolides. Results revealed that chicken were the most contaminated by antimicrobial residues, when compared to beef and milk. The obtained results demonstrate the uncontrolled use of antimicrobials in some Lebanese farms and claim for better management of livestock.

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 (R2 > 0.99) as well as accuracy with coefficients of variation for repeatability and reproducibility lower than 23%. Moreover, the values of decision limit (CCα) and detection capability (CCß) were determined indicating values ranging from 0.13 to 0.86 µg/kg and 0.25-1.72 µg/k for the majority of analytes. Recovery rate in the different matrices varied from 51.5 to 107%. Indeed, this method has been successfully applied to detect anabolic hormones in eighty-eight samples (muscle, liver, kidney, and bile) collected from different local slaughterhouses. Results showed that progesterone was found in 30 samples at concentrations ranging from 0.11 to 11.7 µg/kg, while testosterone was detected in 34 samples at concentrations ranging from 0.5 to 9.52 µg/kg. All bile samples contain epi-testosterone at concentration ranging from 0.89 to 280 µg/kg. These obtained data were used to calculate the estimated daily intake, hazard quotient and hazard index as exposure assessment.

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. Pesticide residues were not observed in 23% of the samples. Whereas pesticide residues were found in 77% of the samples, among them 61% exceeded the maximum residue limits (MRL) and 16% contained residues below the MRL. The most frequently detected pesticide residues were chlorpyrifos (n = 142), methidathion (n = 34), cypermethrin (n = 21), lambda-cyhalothrin (n = 16), myclobutanil (n = 13) and diazinon (n = 9). A preliminary long-term exposure assessment for the detected pesticides in apples showed that Hazard Quotient (HQ) was in the range of 0.1-8% of the ADI's, indicating no risk to human health.

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. Experiments conducted in purified water show an acceleration of SMT and SMP degradation of a factor 1.5 by comparison to drinking water matrix. This difference is due to pH variation and competitive reactions between SNs and mineral and organic compounds, with chlorine in drinking water. In the presence of an excess of chlorine (6.7 µmol·L-1 ) in ultrapure water at pH 7.2, second-order degradation rate constants were equal to 4.5 × 102 M-1 ·s-1 and 5.2 × 102 M-1 ·s-1 for SMT and SMP, respectively. The structures of transformation products were investigated by liquid chromatography tandem mass spectrometry analyses with equimolar concentrations between chlorine and SNs. SO2 elimination, cyclization, and electrophilic substitutions were the main pathways of by-products formation. Moreover, the toxicity of the proposed structures was predicted by using toxicity estimation software tool program. The results indicated that most by-products may present developmental toxicity.

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 = 7.2, temperature = 25 °C, [chlorine] = 3 mg L-1). The result shows a slow degradation of SQX during photolysis compared with chlorination process. Kinetic studies that fitted a fluence-based first-order kinetic model were used to determine the kinetic constants of SQX degradation; they were equal to 0.7 × 10-4 and 0.7 × 10-2 s-1corresponding to the half time lives of 162 and 1.64 min during photolysis and chlorination, respectively. In the second step, seven by-products were generated during a chlorination and photo-transformation of SQX and identified using liquid chromatography with electrospray ionization and tandem mass spectrometry (MS-MS). SO2 extrusion and direct decomposition were the common degradation pathway during photolysis and chlorination. Hydroxylation and isomerization were observed during photodegradation only while electrophilic substitution was observed during chlorination process.

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). The recovery of the target compounds from water samples was most efficient on Waters Oasis HLB SPE cartridge, while acetonitrile/water (60/40) was shown to be the most suitable solvent for desorbing the compounds from SPE. In addition, acidification of samples prior to SPE was optimized to enhance the recovery of the compounds. In terms of method validation, the recoveries of analytes ranged from 68% to 134%. Repeatability and intermediate precision were <11% and 14%, respectively. The method detection limits ranged from 2.3ngL-1 to 94.3ngL-1. An optimized method was applied in a monitoring program to study the occurrence of pharmaceuticals to more than hundred samples collected from rivers, lakes, fountains, and wells overall Lebanon from April to June 2016. Caffeine, erythromycin and its degradation forms, were the most frequently detected compounds at levels reaching >10,000ngL-1 and 2000ngL-1, respectively. Moreover, bacterial analysis showed that the samples were contaminated by Escherichia coli (23%), intestinal Enterococcus (48%) and Pseudomonas aeruginosa (27%). Therefore, in order to evaluate if a correlation exists between finding antibiotics in water samples and the development of resistant-bacteria, an antimicrobial susceptibility test was conducted to the identified isolates using disk diffusion method. Multiple-antibiotic-resistant strains in both intestinal Enterococcus and E. coli were evident in many water samples, while P. aeruginosa was resistant to only one studied antibiotic.

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. Experiments with fortified samples demonstrated that 10 min of ultrasonic treatment with acidified methanol (HCl 2 M) followed by dispersive SPE clean-up with 50 mg PSA gave an effective sample preparation method for several classes of antibiotics in honey. Anhydroerythromycin A, erythromycin A enol ether and desmycosin were used as markers for the presence of erythromycin A and tylosin A in honey samples. The method was validated according to European Commission Decision (EC) No. 2002/657. The recoveries of analytes ranged from 85% to 111%. Repeatability and intra-laboratory reproducibility were < 20.6% and 26.8%, respectively. Decision limit (CCα) and detection capability (CCß) ranged from 6 to 9 µg kg-1 and from 7 to 13 µg kg-1, respectively, except for streptomycin and neomycin, which showed slightly higher CCα at 25 µg kg-1 and CCß at 34 µg kg-1. Finally, the method was applied to the honey test material 02270 through a FAPAS proficiency test (PT) for the determination of tetracyclines. PT results were obtained within a z-score range of ±2, proving that the validated method is suitable for routine analysis to ensure the quality of honey.

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. When combined with centrifugation, the volume of the elution solvent was reduced to 1 mL and the time for sorbent drying decreased also to 10 min under vacuum. Under optimal conditions, recoveries for the 16 U.S. EPA PAHs were between 70 and 85% and the relative standard deviation varied between 1 and 14%. Surrogate standard recoveries were similarly between 61 and 94% with a relative standard deviation between 2 and 15%. The simplicity of the described method, use of less of organic solvent, short procedure time, and good recoveries demonstrate the advantages of this environmentally friendly approach for routine analysis of numerous samples.