Journal of Xenobiotics

The Silway River has historically failed to meet safe fecal coliform levels due to improper waste disposal. The river mouth is located in General Santos City, the tuna capital of the Philippines and a leading producer of hogs, cattle, and poultry. The buildup of contaminants due to direct discharge of waste from chicken farms and existing water quality conditions has led to higher fecal matter in the Silway River. While there were technical reports in the early 2000s about poultry farming, this is the first study where fecal coliform from poultry farming was detected in the Silway River using highly sensitive protocols like qPCR. This study characterized the effect of flow velocity and physicochemical water quality parameters on chicken fecal contamination. Gene markers such as Ckmito and ND5-CD were used to detect and quantify poultry manure contamination through microbial source tracking (MST) and environmental DNA (eDNA) profiling. The results of this study showed the presence of chicken fecal bacteria in all stations along the Silway River. The results revealed that normal levels of water quality parameters such as temperature, pH, and high TSS concentrations create favorable conditions for chicken fecal coliforms to thrive. Multiple regression analysis showed that flow velocity and DO significantly affect chicken fecal contamination. A lower cycle threshold (Ct) value indicated higher concentration of the marker ND5-CD, which means higher fecal contamination. It was found that there was an inverse relationship between the Ct value and both velocity (R² = 0.55, p = 0.01) and DO (R² = 0.98, p = 0.2), suggesting that low flow velocity and low DO can lead to higher fecal contamination. Findings of fecal contamination could negatively impact water resources, the health of nearby residents, and surrounding farms and industries, as well as the health and growth of fish. Full article

Nanoplastics are known to represent a threat to marine ecosystems. Their combination with other contaminants of emerging concerns (CECs) may amplify ecotoxic effects, with unknown impacts on marine biodiversity. This study investigates the effects, single and combined, of bisphenol A (BPA)—one of the most hazardous CECs—and polystyrene nanoparticles (PS NPs)—as a proxy for nanoplastics, being among the most commonly found asmarine debris—on cholinesterase (ChE) activities of the ascidian Ciona robusta. ChE activity was first measured in the siphons, tunic, and viscera of wild-caught adult specimens and exposed in vitro to BPA (0.01, 0.21, 0.69 mM) and PS NPs (0.0096–0.096 mM; 8.096 × 10⁹–10¹⁰ particles, respectively) alone and combined for 15 min of incubation. PS NPs’ behavior in milliQ water and in the ChE assay reaction buffer was characterized alone, combined with BPA, and analyzed through ζ-potential measurements via Dynamic Light Scattering. The results revealed that ChE activity was predominant in the viscera and siphons of C. robusta; PS NPs did not affect the ChE activity alone or combined, while BPA caused a concentration-dependent inhibition of ChE activity in the viscera. No changes in ζ-potential were observed for PS NPs alone or combined with BPA in the ChE buffer, suggesting no interaction. Further investigations are needed to understand the potential neurotoxic consequences for C. robusta and ecological risk scenarios due to exposure to BPA and nanoplastics in marine coastal waters. Full article

The present study focused, for the first time, on the adverse effects of nine REEs on the marine copepod Tigriopus fulvus. For this purpose, copepod mortality, immobilization, and naupliar development were assessed. Overall, the results demonstrated that all REEs tested exerted significant adverse effects on T. fulvus, with LC50 values ranging from 0.56 to 1.99 mg/L. Concentration-dependent increases in mortality and immobilization for all tested REEs were observed. Following exposure of nauplii to REEs, a significant slowing of nauplii development was shown with all REEs tested. The results obtained clearly highlight the potential toxicity of REEs, and, in particular, of Lanthanum, which could have consequences on the survival and development of T. fulvus, affecting the copepod population. Full article

In the field of computational chemistry, computer models are quickly and cheaply constructed to predict toxicology hazards and results, with no need for test material or animals as these computational predictions are often based on physicochemical properties of chemical structures. Multiple methodologies are employed to support in silico assessments based on machine learning (ML) and deep learning (DL). This review introduces the development of computational toxicology, focusing on ML and DL and emphasizing their importance in the field of toxicology. A fine balance between target potency, selectivity, absorption, distribution, metabolism, excretion, toxicity (ADMET) and clinical safety properties should be achieved to discover a potential new drug. It is advantageous to perform virtual predictions as early as possible in drug development processes, even before a molecule is synthesized. Currently, there are numerous commercially available and free web-based programs for toxicity prediction, which can be used to construct various predictive models. The key features of the QSAR method are also outlined, and the selection of appropriate physicochemical descriptors is a prerequisite for robust predictions. In addition, examples of open-source tools applied to toxicity prediction are included, as well as examples of the application of different computational methods for the prediction of toxicity in drug design and environmental toxicology. Full article

Temephos is an organophosphorus pesticide widely used as a larvicide in public health campaigns to control vector-borne diseases. Data on the urinary elimination of temephos metabolites are limited, and there is no validated biomarker of exposure for its evaluation. This study aimed to determine the urinary excretion kinetics of temephos and its metabolites in adult male rats. Hence, adult male Wistar rats were administered orally with a single dose of temephos (300 mg/kg). Urine samples were collected at different time intervals after dosing and enzymatically hydrolyzed using β-glucuronidase/sulfatase from H. pomatia. The metabolites were extracted and analyzed by HPLC-DAD. The metabolites detected were 4,4′-thiodiphenol (TDP), 4,4′-sulfinyldiphenol (SIDP), 4,4′-sulfonyldiphenol (SODP), or bisphenol S (BPS), a non-identified metabolite, and only traces of the parent compound. The mean urine concentrations of metabolites were used for kinetic analysis. Urinary levels of TDP were fitted to a two-compartmental model, and its half-lives (t_1/2 Elim-U) were 27.8 and 272.1 h for the first and second phases, respectively. The t_1/2 Elim-U of BPS was 17.7 h. TDP, the main metabolite of temephos, was eliminated by urine and is specific and stable. Therefore, it may be used as a biomarker of temephos exposure. Full article

Over the last decades, the human species has seen an increase in the incidence of pathologies linked to the genitourinary tract. Observations in animals have allowed us to link these increases, at least in part, to changes in the environment and, in particular, to an increasing presence of endocrine disruptors. These can be physical agents, such as light or heat; natural products, such as phytoestrogens; or chemicals produced by humans. Endocrine disruptors may interfere with the signaling pathways mediated by the endocrine system, particularly those linked to sex hormones. These factors and their general effects are presented before focusing on the male and female genitourinary tracts by describing their anatomy, development, and pathologies, including bladder and prostate cancer. Full article

The increasing consumption of chia seeds is followed by a growing interest in their nutritional and toxicological characterization. To assess the characterization of the essential and PTEs of this novel food, 20 samples of conventional and organic chia seeds available on the European market were analyzed using ICP-OES. Then, the dietary exposure to these elements was assessed. An exhaustive investigation into the metal content of this food serves to elucidate the paucity of existing knowledge. The results show that the levels of essential elements are similar in both types of production, while the levels of PTEs are higher in the organic samples. The exposure assessment indicates that Mn contributes the most among the essential elements, followed by Cu in women. Exposure to PTEs through doses of 50 g/day of chia seeds analyzed would hardly pose short-term health risks as the contributions are below 10%, except for Sr, although they could produce a long-term toxicological risk. To promote safety in chia seed consumption, it is recommended to encourage responsible and moderate consumption, continue monitoring PTE levels in this novel food, and establish concentration limits for PTEs in future European regulations. Full article

Polyethylene and polystyrene are massively used around the world in various applications and are the most abundant plastic waste. Once in the marine environment, under the influence of physical and chemical factors, plastic products degrade, changing from the size category of macroplastics to microplastics. In order to study the effect of plastic on marine organisms, we modeled the conditions of environmental pollution with different-sized plastic—polystyrene microparticles of 0.9 µm and macro-sized polyethylene fragments of 10 cm—and compared their effect on biochemical parameters in the tissues of the bivalve mollusk Mytilus trossulus. Using biomarkers, it was found that regardless of the size and type of polymer, polystyrene microparticles and polyethylene macrofragments induced the development of oxidative stress in mussels. A significant decrease in the level of lysosomal stability in mussel hemocytes was observed. Increases in the level of DNA damage and the concentration of malonic dialdehyde in the cells of gills and the digestive gland were also shown. The level of total antiradical activity in cells varied and had a tissue-specific character. It was shown that both ingested polystyrene particles and leachable chemical compounds from polyethylene are toxic for mussels. Full article

Pharmaceutical residues in aquatic ecosystems pose significant environmental and public health challenges. Identifying the presence and levels of these pharmaceuticals is crucial. This study developed an analytical method to detect pharmaceuticals used for Alzheimer’s (AD) and Parkinson’s (PD) disease, including psychiatric drugs and the stimulant caffeine, targeting 30 compounds. Optimized mass spectrometric and liquid chromatographic parameters enabled robust detection and quantification. The methodology was applied to 25 surface and wastewater samples. Twenty-one compounds were detected including eight psychiatric drugs, five metabolites (citalopram N-oxide, citalopram propionic acid, desmethylcitalopram, O-desmethylvenlafaxine, and 10,11-epoxycarbamazepine), and seven AD/PD pharmaceuticals along with caffeine. Nine compounds (apomorphine, benserazide, donepezil, didemethylcitalopram, carbidopa, norfluoxetine, galantamine, pramipexole, and safinamide) were not detected. Fluoxetine was found in all samples, and caffeine had the highest concentration at 76,991 ng/L, reflecting its high consumption. Concentrations ranged from 29.8 to 656 ng/L for caffeine, <MDL to 381 ng/L for psychiatric drugs, and <MDL to 37.1 ng/L for AD and PD pharmaceuticals in surface water. In wastewater, concentrations ranged from 140 to 76,991 ng/L for caffeine, <MDL to 5227 ng/L for psychiatric drugs, and <MDL to 206 ng/L for AD and PD pharmaceuticals. These findings highlight the critical need for comprehensive environmental monitoring. Full article

Emerging pharmaceutical pollutants like ciprofloxacin (CIP) and ibuprofen (IBU) are frequently detected in aquatic environments, posing risks to ecosystems and human health. Since pollutants rarely exist alone in the environment, understanding the thermal stability and degradation kinetics of these compounds, especially in mixtures, is crucial for developing effective removal strategies. This study therefore investigates the thermal stability and degradation kinetics of CIP and IBU, under different heating rates. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were employed to examine the thermal behavior of these compounds individually and in mixture (CIP + IBU) at heating rates of 10, 20, and 30 °C/min. The kinetics of thermal degradation were analyzed using both model-fitting (Coats–Redfern (CR)) and model-free (Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Friedman (FR)) methods. The results showed distinct degradation patterns, with CIP decomposing between 280 and 550 °C and IBU between 152 and 350 °C, while the mixture exhibited multistep decomposition in the 157–500 °C range. The CR model indicated first-order kinetics as a better fit for the degradation (except for IBU). Furthermore, CIP exhibits higher thermal stability and activation energy compared to IBU, with the KAS model yielding activation energies of 58.09 kJ/mol for CIP, 11.37 kJ/mol for IBU, and 41.09 kJ/mol for CIP + IBU mixture. The CIP + IBU mixture generally showed intermediate thermal properties, suggesting synergistic and antagonistic interactions between the compounds. Thermodynamic parameters (ΔH°, ΔG°, ΔS°) were calculated, revealing non-spontaneous, endothermic processes for all samples (except in the FWO method) with a decrease in molecular disorder and positive ΔG° values across all models and heating rates. The study found that higher heating rates led to less thermodynamically favorable conditions for degradation. These findings provide important information concerning the thermal behavior of these pharmaceutical pollutants, which can inform strategies for their removal from the environment and the development of more effective waste-treatment processes. Full article

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are persistent environmental pollutants, raising concerns due to their widespread presence and disruptive biological effects. These compounds are highly stable, allowing them to bioaccumulate in the environment and living organisms, potentially impacting critical physiological functions such as hormonal balance, immune response, and increasing cancer risk. Despite regulatory restrictions, their pervasive nature necessitates further research into their potential effects on cellular and neuronal function. This study first evaluated the cytotoxic effects of PFOS and PFOA on S1 neuroblastoma cells; a dose-dependent reduction in cell viability was revealed for PFOS, while PFOA exhibited minimal toxicity until millimolar concentrations. We further investigated their potential to modulate GABAergic neurotransmission using patch-clamp electrophysiology. Both PFOS and PFOA caused a significant but reversible reduction in GABA receptor-mediated currents following one-minute pre-treatment. These findings suggest that PFOS and PFOA can interfere with both cellular viability and GABAergic signaling, providing critical insights into their functional impacts and highlighting the need for further investigation into the long-term consequences of PFAS exposure on nervous system health. Full article

Contamination of marine ecosystems by pharmaceutically active compounds (PhACs) deserves more research since their environmental fate differs from that observed in freshwater systems. However, knowledge remains scarce, especially in semi-arid coastal regions of the Global South. This study investigates the occurrence and distribution of caffeine, carbamazepine, ciprofloxacin, and sulfamethoxazole in sediments from the La Paz lagoon, a coastal system in a semi-arid region of Mexico with inverse estuarine conditions. Samples of superficial sediments (0–5 cm depth) were collected from 18 sampling points distributed through the lagoon, encompassing sites heavily polluted by discharges of municipal sewage and 3 potentially pristine sites far from the urban and peri-urban zones. Also, a 25 cm length sediment core was taken and divided into 1 cm sub-samples to determine the deposition of target PhACs in the sediment bed through time. The extraction of the target PhACs was performed through the accelerated solvent extraction (ASE) technique and quantification was achieved using a validated HPLC-MS/MS analytical method. The concentration of caffeine, carbamazepine, ciprofloxacin, and sulfamethoxazole in superficial sediment oscillated in the range of 1 to 45 ng g⁻¹ (dry weight). The highest mass fraction of target PhACs was detected in sites impacted by wastewater discharges. The caffeine-to-carbamazepine ratio was determined for the first time in marine sediments impacted by wastewater discharges, resulting in values from 4.2 to 9.12. Analysis of the 25 cm length sediment core revealed a high dispersion of caffeine, which was attributed to high water solubility, while antibiotics were predominantly detected in the upper 20 cm of the core. Risk quotients were calculated, observing low risk for caffeine, carbamazepine, and ciprofloxacin, while sulfamethoxazole presented high risk in all the sampling points. PhACs are retained in superficial sediments from a lagoon impacted by wastewater discharges, and the level of impact depends on the properties of the compounds and the TOC content in sediments. Risk assessments should be performed in the future considering the combination of pharmaceuticals and byproducts in marine sediments. This research emphasizes the importance of sewage management in preserving marine ecosystems in semi-arid regions in the Global South. Full article

Nerve agents are usually identified as exceedingly toxic organophosphate compounds like VX and sarin. Nevertheless, although carbamate nerve agents (CNAs) have been developed they constitute the least studied class of nerve agents outside military literature. Recently, CNAs gained popularity after the inclusion of a small subset of carbamate agents in the Chemical Weapons Convention (CWC) list of Schedule 1 chemicals. Here, a holistic approach was used to identify and categorize the developed CNAs. It is demonstrated that CNAs encompass a highly diverse class of compounds. Their main characteristics include an aromatic group that carries the carbamate moiety. Based on their chemical structure, CNAs were categorized into two generations that are further divided into various subclasses. The second generation of CNAs includes some members that exhibit higher toxicity than VX. CNAs have not been used in any conflict, which may be related to their solid nature that requires sophisticated delivery systems. Since, however, CNAs can be applied as poisons in individualized cases, understanding their chemistry and toxicological properties is important for the development of effective countermeasures. Full article

Since iron oxide nanoparticles (IONPs) are expected to be important tools in medical care, patients with inflammatory diseases will be increasingly exposed to IONPs in the future. Here, we assessed the short- and long-term impact of polysaccharide (PS)-coated IONPs on mice with persistent systemic inflammation. To this end, PS-IONPs were synthetized by a core-shell method. Mice were regularly injected with sterile zymosan. PS-IONPs were administered intravenously. At specific nanoparticle injection post-observation times, the organ iron concentration was determined via atomic absorption spectrometry, the expression of NF-κB-related proteins using SDS-PAGE and immunoblotting, as well as body weight and haemograms. Finally, the mediator secretion in blood plasma was analysed using multiplexed ELISA. Our data show that PS-IONPs induce short-term changes of iron levels in distinct organs and of NF-κB p65 and p50, p100, COX-2s, and Bcl-2 protein expression in the liver of inflammatory stressed mice. In the long term, there was an attenuated expression of several NF-κB–related proteins and attenuated features of inflammatory-based anaemia in blood. PS-IONPs weakly influenced the blood cytokine levels. PS-IONPs are biocompatible, but given their short-term pro-inflammatory impact, they should prospectively be applied with caution in patients with inflammatory diseases of the liver. Full article

Processed foods, accounting for most consumable food categories today, contain considerable amounts of food additives. Food additives are substances added to food products to improve taste, consistency, appearance, or shelf life. Various food additives, such as phthalates, bisphenol A, tartrazine, erythrosine, artificial sweeteners, and parabens, have been identified as potential sources of endocrine-disrupting chemicals (EDCs) in processed foods. EDCs are substances that frequently interfere with the regular functioning of the endocrine system, creating an unusual environment in the biological system, which leads to adverse health effects such as the disruption of hormone synthesis, receptor binding, and signal transduction pathways, as well as energy metabolic homeostatic disorders which potentially increasing the risk of obesity, type-2 diabetes, cardiometabolic diseases and may also trigger allergic reactions. Consequently, they can also impact mammary gland development, and reproductive function, further leading to developmental abnormalities. This review aims to insights into the various food additives that act as potential endocrine-disrupting chemicals (EDCs) and to describe their applications in the food industry, as well as the failure of hormonal homeostatic mechanisms, which eventually result in hazardous health effects. It also outlines strategies to reduce the use of food additives and suggests alternative additives with minimal or no endocrine-disrupting properties, highlighting their importance for maintaining human health. Full article

Chromium is an essential element in various industrial processes, including stainless steel production, electroplating, metal finishing, leather tanning, photography, and textile manufacturing. However, it is also a well-documented contaminant of aquatic systems and agricultural land, posing significant economic and health challenges. The hexavalent form of chromium [Cr(VI)] is particularly toxic and carcinogenic, linked to severe health issues such as cancer, kidney disorders, liver failure, and environmental biomagnification. Due to the high risks associated with chromium contamination in potable water, researchers have focused on developing effective removal strategies. Among these strategies, biosorption has emerged as a promising, cost-effective, and energy-efficient method for eliminating toxic metals, especially chromium. This process utilizes agricultural waste, plants, algae, bacteria, fungi, and other biomass as adsorbents, demonstrating substantial potential for the remediation of heavy metals from contaminated environments at minimal cost. This review paper provides a comprehensive analysis of various strategies, materials, and mechanisms involved in the bioremediation of chromium, along with their commercial viability. It also highlights the advantages of biosorption over traditional chemical and physical methods, offering a thorough understanding of its applications and effectiveness. Full article

The application of pesticides remains a necessary measure for pest management in agriculture, particularly in the cultivation of fruits and vegetables. After harvest, the presence of pesticide residues in greengrocery (fruits and vegetables) is significantly influenced by various factors, including storage conditions, handling practices, and subsequent processing methods. The mitigation of these residues to levels compliant with regulated maximum thresholds ensures the safety of raw and processed fruits and vegetables for consumption. A contemporary survey of pesticide residues in greengrocery has gathered considerable attention from consumers, driven by concerns over the potential health risk of pesticide exposure. Consequently, consumers want to be extensively informed about household processing techniques to minimize associated risks. Meanwhile, a critical question arises: does household processing effectively eliminate pesticide residues? A comprehensive review of the literature reveals that conventional methods, such as washing and soaking, offer only limited reduction in residue levels, while emerging treatments, suitable both at household and industrial scale, demonstrate increased efficiency in residues mitigation. This study aims to emphasise the ubiquitous use of pesticides in crop cultivation while providing recommendations for the implementation of efficient treatment protocols to address residue concerns. Following upon available evidence and database mining, the worldwide purpose must be to outline agriculturally and economically viable strategies that prioritize both the health and safety of consumers, as well as the green cultivation and processing of fruits and vegetables. Full article

The association between embryo morphokinetics and its developmental competence is well documented. For instance, early cleaved embryos are more competent in developing to blastocysts, whereas the proportion of abnormally cleaved embryos that further developed to blastocysts is low. Numerous factors, such as the parental age, lifestyle, health, and smoking habits have been reported to affect the embryo morphokinetics and, consequently, its development. However, less is known about the effect of environmental stressors on embryo morphokinetics. The current review discusses the effect of the most concerning environmental stressors on embryo morphokinetics. These stresses include heat stress and human-made chemicals such as phthalates (e.g., bis-(2-ethylhexyl phthalate, dibutyl phthalate, dimethyl phthalate, and their primary metabolites), herbicides (e.g., diaminochlorotriazine, the primary metabolite of atrazine), pharmaceutical compounds (e.g., carbamazepine, nocodazole) and pro-oxidant agents (cumene hydroperoxide, Triton X-100), as well as naturally occurring toxins such as mycotoxin (e.g., aflatoxin B1 and its metabolite, and ochratoxin A). In addition, this review discusses the effect of ionizing or non-ionizing radiation and viral infections (e.g., SARS-CoV-2, papillomavirus). Finally, it points out some potential mechanisms that underlie the impairment of embryo morphokinetics, and it suggests protective compounds, mainly the supplementation of antioxidants to improve the morphokinetics, and consequently, the embryo developmental competence. Full article

Growing evidence suggests physiological and pathological functions of lung and gut microbiomes in various pathologies. Epidemiological and experimental data associate air pollution exposure with host microbial dysbiosis in the lungs and gut. Air pollution through increased reactive oxygen species generation, the disruption of epithelial barrier integrity, and systemic inflammation modulates microbial imbalance. Microbiome balance is crucial in regulating inflammation and metabolic pathways to maintain health. Microbiome dysbiosis is proposed as a potential mechanism for the air-pollution-induced modulation of pulmonary and systemic disorders. Microbiome-based therapeutic approaches are increasingly gaining attention and could have added value in promoting lung health. This review summarizes and discusses air-pollution-mediated microbiome alterations in the lungs and gut in humans and mice and elaborates on their role in health and disease. We discuss and summarize the current literature, highlight important mechanisms that lead to microbial dysbiosis, and elaborate on pathways that potentially link lung and lung microbiomes in the context of environmental exposures. Finally, we discuss the lung–liver–gut axis and its potential pathophysiological implications in air-pollution-mediated pathologies through microbial dysbiosis. Full article