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Lebanon's agricultural sector, known for its diverse crop and livestock production, faces challenges in the international market due to the presence of chemical residues and contaminants in its food exports. Recent rejections of these exports have raised global concerns about food safety, increasingly seen as vital for public health and economic prosperity. This review focuses on examining scientific studies about the levels of various chemical residues including pesticides, and veterinary drugs and contaminants like mycotoxins, and polycyclic aromatic hydrocarbons, and heavy metals in Lebanese food products. Findings indicate that these residues and contaminants often exceed both the maximum residue limits (MRLs) and maximum limits (MLs) set by the Codex Alimentarius and the European Union. The review concludes with recommendations for reducing these contaminants and residues to enhance Lebanon's food safety and quality, aligning with international standards, and mitigating the risk of export rejections. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Simple Summary: The involvement of the oviductal epithelial cells and progesterone hormone on the sperm fertilizing ability was investigated here by using an in vitro fertilization (IVF) swine model. By using different techniques, we demonstrated that oviductal epithelial cells (OECs) pre-treated with progesterone (P4) at 100 ng/mL represent the ideal environment for sperm capacitation, inducing a positive effect on the sperm acquisition of the fertilizing ability. Moreover, treatment of OECs with P4 modifies OVGP1,SPP1 and DMBT1 gene transcription but does not interfere with important cytoskeleton structures or cell doubling time, thereby allowing the correct development and progression of important biochemical pathways and signal transduction processes. 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 two sulfonamides, namely sulfamethazine (SMT) and sulfamethoxypyridazine (SMP), was investigated in order 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, 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 4.5x102 and 5.2x102 M-1s-1 for SMT and SMP, respectively. The structures of transformation products were investigated by LC-MS/MS 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 T.E.S.T. program. The results indicated that the majority of by-products may present developmental toxicity. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess the dissolved concentration of 45 pesticides in the surface waters of the Lebanese Republic using Polar Organic Chemical Integrative Sampler "POCIS". All of the sampling sites are located in the major agricultural land areas in Lebanon. POCIS (n = 3) were deployed at Ibrahim River, Qaraoun Lake and Hasbani River for a duration of 14 days. The total concentration of pesticides ranged from not detected (nd) to 137.66 ng.L. Chlorpyrifos, DDE-pp, diazinon and Fenpropathrin were the most abundant compounds. Qaraoun Lake and Hasbani River were found to be more polluted than Ibrahim River, since they receive large amounts of waste water derived from nearby agricultural lands and they had the lowest dilution factor. The aqueous average concentration of the target compounds were estimated using sampling rates obtained from the literature. Comparison between Time Weighed Average concentrations "TWA" using POCIS and spot sampling is presented. Results showed that POCIS TWA concentrations are in agreement with spot sampling concentrations for Ibrahim and Hasbani Rivers. The toxicity of the major detected pesticides on three representative aquatic species ( Daphnia magna, Scenedesmus quadricauda and Oncorhynchus mykiss) is also reported. [ABSTRACT FROM AUTHOR]

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 (CCβ) 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 CCβ 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. [ABSTRACT FROM AUTHOR]

A new and simple method has been developed for determination and quantification of 12 aminoglycosides in environmental water samples. The method is based on solid-phase extraction (SPE) followed by liquid chromatography coupled with tandem mass spectrometry (LC-ESI-MS/MS) for analysis. After optimization of LC-ESI-MS/MS conditions, two SPE cartridges, reversed-phase C18 with pentafluoropropionic acid (PFPA) and polymeric mixed mode cation exchange cartridges, have been tested to determine aminoglycoside residues in water. Parameters affecting the extraction efficiency for the two cartridges such as eluent type, percolation volume and percentage of ion pair PFPA were optimized. Extraction on C18 cartridges with PFPA reagent showed a better result in terms of recovery (65-115 %) and relative standard deviation (0.5-15 %) relative to strong cation exchange. This method was validated and their limits of quantification were in the range 5-50 ng L. The method was applied to evaluate the occurrence of these compounds in influent and effluent wastewater treatment plant and hospital water samples in Lebanon. Gentamycin was found in hospital wastewater samples at a concentration of 30 ng L. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]