Background: Metabolic dysfunction-associated fatty liver disease (MAFLD) is a common metabolic disorder in which the gut–liver axis plays a key role. Titanium dioxide nanoparticles (TiO₂), common food additives, may affect gut microbiota and health. This study investigates the role of Akkermansia muciniphila and its outer membrane vesicles (OMVs) in TiO₂-induced MAFLD under a high-fat diet (HFD). Methods: Low-dose TiO₂ was co-incubated with A. muciniphila to assess its effects on growth and OMV production. OMVs derived from TiO₂-treated A. muciniphila were then co-cultured with hepatocytes to assess their impact on lipid accumulation. In vivo, mice were fed control or HFD with/without TiO₂ for 13 weeks. Hepatic lipid deposition, inflammatory cytokines, intestinal barrier integrity, and gut microbiota composition were assessed. Fecal OMVs were isolated for proteomic analysis and integrated with hepatic metabolomics to explore regulatory pathways. In the next experiment, mice were divided into HFD, HFD+TiO₂, HFD+A. muciniphila, and HFD+TiO₂+A. muciniphila groups to assess the protective effects of A. muciniphila. Results: Low-dose TiO₂ promoted A. muciniphila growth and OMV production. OMVs from TiO₂-treated bacteria reduced lipid accumulation in hepatocytes. TiO₂ reduced hepatic lipids under the control diet but exacerbated steatosis and inflammation under the HFD, associated with altered lipid metabolism genes and an impaired intestinal barrier. Metagenomic analysis showed that TiO₂ reshaped gut microbiota, increasing A. muciniphila under the control diet but decreasing it under the HFD. OMV proteomics and liver metabolomics revealed enrichment in lipid and energy metabolism pathways. Supplementation with A. muciniphila alleviated TiO₂-aggravated hepatic lipid accumulation in vivo. Conclusion: TiO₂ exacerbates HFD-induced MAFLD by altering gut microbiota, impairing gut barrier function, and promoting hepatic lipid accumulation and inflammation. Under the control diet, TiO₂ increases A. muciniphila, reducing hepatic lipid accumulation. Supplementation with A. muciniphila and its OMVs reverses these effects, suggesting TiO₂ may influence MAFLD progression via the modulation of specific gut microbes.

2,4,6-Tribromophenol (TBP) is a widely used flame retardant and biocide. Studies have detected TBP in a variety of human samples, such as blood and urine, and linked it to thyroid dysfunction, carcinogenicity and reproductive toxicity. Additionally, TBP is a precursor of 2,4,6-Tribromoanisole (TBA), a characteristic musty/corky-smelling compound with an odour threshold concentration (OTC) of 0.008-10 ng L^-1. TBA is commonly formed through microbial methylation of TBP in environmental conditions. Compounds belonging to the Taste and Odor category have attracted substantial interest from the scientific community, and considering that water is vital for life, the possible adverse effects of these compounds on humans are of great concern.

Given that TBP and TBA can co-exist in the environment, and consequently, humans can be exposed to both of them, the possible adverse effects of the individual compounds, as well as their mixture, was investigated. A Cytokinesis-Block Micronucleus (CBMN) assay was utilized in order to evaluate the possible cyto-genotoxic effects of the aforementioned compounds. CBMN is a simple, rapid and reliable method.

In this study, whole blood was exposed to representative concentrations of each compound and their mixture (0.125 -1 mg L^-1). Based on the preliminary results, TBP presented significant genotoxic effects only at the highest tested concentration. Genotoxic effects were also observed at the highest concentrations of the mixture. This work highlights the importance of the cyto-genotoxic evaluation of compounds that commonly co-exist in the environment as mixtures.

Acknowledgements: This paper has been financed by E.Y.D.A.P. within the framework of the IKY-EYDAP Scholarship program academic year 2022-23.

Microplastics (MPs), defined as plastic particles smaller than 5 mm, are persistent and widespread in both aquatic and terrestrial ecosystems owing to the mismanagement of plastic waste [1, 2]. These particles undergo aging through environmental weathering, increasing their toxicity and capacity to adsorb pollutants [3, 4]. These particles can cause physical stress, inflammation, oxidative damage, and immune responses, potentially contributing to diseases such as cancer, metabolic disorders, and neurodevelopmental conditions [5]. In response to growing concerns, the revised EU Urban Wastewater Treatment Directive highlights the need to reduce the release of target micropollutants, including MPs, into the environment [6]. In this study, the potential of biodegradation using the enzyme laccase was investigated as an eco-friendly and sustainable approach for their removal from wastewater. According to previous studies, laccase can break polymer bonds, potentially reducing environmental persistence and toxicity [7]. Three of the most common types of MPs were tested: low-density polyethylene (LDPE, 300 and 600 µm), polyethylene terephthalate (PET, 300 µm), and polyamide nylon 6 (PA6, 20 µm). Laccase concentrations ranging from 50 to 200 U/L were applied over a 7-day incubation period, and enzyme activity was determined using the ABTS oxidation method. MP samples were analyzed using FTIR and Raman spectroscopy to assess their structural modifications. The results indicated potential surface alterations evidenced by increased fluorescence in the Raman spectra; however, further optimization is required to enhance the degradation of specific functional groups and improve biodegradation efficiency.

References

1. Gao, Y., et al. Sci Total Environ 2024, 957: 177427
2. Wang, L., et al. Chemosphere 2023, 315: 137744
3. Martinho, S.D., et al. Toxic Effects of Micro‐ and Nanoplastics: Environment, Food and Human Health, Wiley, 2024
4. Binda, G., et al. TrAC Trends in Analytical Chemistry 2024, 172
5. Molina, E. and S. Benede. Front Nutr 2022, 9: 910094
6. Directive (EU) 2024/3019 of the European Parliament and of the Council of 27 November 2024 concerning urban wastewater treatment (recast)
7. Ramamurthy, K., et al. Int J Biol Macromol 2024, 276,133971

In the context of the Anthropocene, river ecosystems have been profoundly altered by the intensification of anthropogenic activities that modify their physical, chemical, and biological characteristics. The continuous discharge of urban, industrial, and agricultural effluents has generated a substantial deterioration in water quality, compromising biodiversity and ecosystem functions. Globally, it is estimated that approximately 50% of major river systems are polluted; in Mexico, this figure reaches nearly 60%, underscoring the urgency of implementing bioindicator tools for environmental assessment and monitoring. The objective of this study was to evaluate the genotoxic and cytotoxic potential of water and sediment samples from the Briones and Negros rivers (Tlaxcala, Mexico) by applying the micronucleus (MN) test and the comet assay in Vicia faba cells. Spot sampling was carried out during the rainy and dry seasons at five representative sites. The results showed statistically significant increases (p < 0.05) in MN frequency, DNA fragmentation, and a reduction in the mitotic index (MI) in most of the samples evaluated compared to negative controls. Marked spatial and temporal variability was observed, suggesting differential exposure to toxic agents. The presence of compounds such as polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides, and heavy metals is postulated as a possible cause of the observed effects. These findings confirm the existence of contaminants with genotoxic and cytotoxic potential in the studied water bodies, which represent not only a threat to the ecological integrity of aquatic ecosystems but also a latent risk to human health. The implementation of comprehensive genotoxicological monitoring programs is recommended, as well as the development of strategies for ecological restoration and mitigation of anthropogenic impacts.

To meet the global demand for food due to the world's rapidly growing population , pesticides are widely used worldwide. Modern agriculture has been enhanced by the use of pesticides to control many phytopathogenic infections. In 2020, pesticide concentrations exceeded the threshold of concern at 22% of European river and lake sampling points. Likewise, 83% of agricultural soils tested in 2019 contained pesticide residues. Fungicides and bactericides was the top selling pesticide group in 2022. In agriculture, the use of agrochemicals is justified for three main reasons: (a) increased production, (b) improved crop quality, and (c) reduced labor and energy consumption in production. Tang et al., (2021), found that 64% of the world's agricultural land (roughly 24.5 million km²) is at risk of pesticide contamination due to the presence of more than one active ingredient, and 31% is at high-risk zones. This staggering figure emphasizes the need for heightened safety measures and public awareness of pesticide use. The extensive persistence of these inputs results in their potential bioaccumulation in non-target organisms, resulting in their detection across diverse biotic matrices. Given the interconnectedness of organisms in trophic networks, these residues can spread through trophic transfer and affect food webs. The greater the volume of pesticides applied on land, the greater the spread to the aquatic ecosystem through meteorological activities, creating serious ecotoxicological risks. Therefore, the aim of this systematic review is to investigate the most widespread pesticide formulations used on crops, their acute and chronic toxicity, persistence and associated risks to human health.

Smoking is not only a main contributing cause in several diseases with implications in human health, but as the most popular habit with global consumption, it has severe implications and impact on the ecosystem, something that remains uncontrolled. Smoking leaves behind cigarette filter butts, which take up to fifteen years to decompose and can concentrate a great number of toxic compounds. These compounds leach out into the aqueous environment, polluting surface waters. Pollution assessment is based on the detection of chemicals and pollutants in the environment to estimate quality; however, such measurements are merely descriptive and provide, to their limit of detection, a report of the panel of pollutants present without any mechanistic information for their action. Therefore, water chemistry methods cannot predict the appearance of specific pollutants early. This is the reason why in the latest years' environmental risk assessment and monitoring are moving towards effect-based methods and novel approach methodologies as more sensitive tools for risk assessment. These approaches use biological systems and molecular information as new metrics for monitoring. Focusing on the freshwater ecosystem, the water flea is a sentinel organism used extensively in ecotoxicology. Combining phenotypic and holistic approaches, we screened for the molecular effects of a cigarette and an e-cigarette on daphnids following the analysis of filter extracts to assess their chemical composition. We identified perturbations in the physiology and metabolism of daphnids with feeding, enzyme activities, mortality and survival, and metabolic perturbations. Aiming to elevate the water flea as an equivalent to “a canary in the coal mine”, we intend to identify the presence of cigarette pollutants in the environment in actual river samples.

This study analyzed spatial and temporal patterns of surface water quality, specifically focusing on nutrient-related parameters in the Greater Houston Area (GHA), Texas. It addressed two key questions: (1) How have population growth and changes in land use over the past four decades influenced water quality over time and across space? (2) Have ongoing pollution control efforts effectively maintained water quality over the past 40 years? We analyzed water quality data from 20 stations in GHA, focusing on total nitrogen, total phosphorus, dissolved oxygen, total solids, fecal coliform, and pH levels. The Mann–Kendall test and Sen’s slope estimator were utilized to detect long-term trends. The results show that nutrient pollution is increasingly becoming a significant issue in the GHA. Our spatial analysis reveals that water quality is inversely correlated with population density and the percentage of impervious land cover. This suggests areas with higher population density are more prone to water quality degradation. Mann–Kendall trend analysis indicates a strong increasing trend in fecal coliform, total nitrogen, and total phosphorus at stations situated in heavily urbanized counties. In contrast, these parameters remain stable in less populated counties, despite rapid population growth. The results demonstrate that the ongoing pollution control efforts have not been equally effective across the study area. These findings highlight the challenges in densely populated counties and underscore the necessity of sustained water pollution control and long-term monitoring efforts.

Highlights

• The simultaneous analysis of pesticide residues and mycotoxins in nuts is reported for the first time;
• The acetonitrile-based sample preparation provided satisfactory extraction;
• The two-step cleanup strategy effectively minimised the matrix effects;
• The performance of the method complied with the national (FSSAI) and international regulatory requirements and guidelines.

For the first time, a multiresidue analytical method is reported for the simultaneous analysis of multi-class pesticides and mycotoxins in nuts (groundnut, almond, cashew, and pistachio). The optimised sample preparation method involved comminution with water, extraction by acetonitrile, and cleanup using dispersive solid-phase extraction with a C₁₈ sorbent followed by a freezing step at - 80º C. The final analysis was carried out using liquid chromatography coupled with tandem mass spectrometry. The method performance was evaluated on 208 multi-class pesticides and mycotoxins [aflatoxins and ochratoxin A]. The strategies minimised the matrix effects and achieved suitable LOQs for checking regulatory compliance. The findings indicated satisfactory recoveries (70 - 110 %) at an LOQ of 0.01 mg/kg and higher levels with repeatability < 16 % RSD. Notably, the extraction and analysis using a single chromatographic run provided satisfactory selectivity, sensitivity, quantification, and accuracy (recovery and precision) for target compounds during single laboratory studies. The developed method complied with the regulatory requirements as well as international analytical quality control guidelines.

The irregular disposal of effluents and agropastoral waste promotes artificial eutrophication, favoring the proliferation of cyanobacteria in water bodies. In addition to nutrients, antibiotics frequently reach these environments, further limiting water quality and impacting aquatic biota. During the SARS-CoV-2 pandemic in Brazil, the indiscriminate use of azithromycin (AZT) significantly increased its concentrations in water bodies, with concentrations reaching up to 2.85 µg L⁻¹, a value four times higher than that reported before the pandemic. This study investigated the effect of environmentally relevant concentrations of AZT on the feeding behavior of the zooplankton Daphnia similis in the presence of the toxic cyanobacterium Microcystis aeruginosa (LETC-MC-25). After 12 h of starvation, two individuals per replicate (n = 4) were incubated for 6 hours in tubes containing 20 mL of RT medium with different diets (chlorophytes and/or cyanobacteria, totaling 1000 µgC L⁻¹) and AZT concentrations (0.3, 0.6, and 3.0 µg L⁻¹), totaling 16 treatments. A control with chlorophytes, individual treatments, and combinations of the antibiotic with cyanobacteria at concentrations of 125, 250, and 500 µgC L⁻¹ were evaluated. Isolated exposure to AZT did not significantly alter the feeding behavior of the organisms. In contrast, a single exposure to M. aeruginosa reduced the clearance rate by up to 34%. However, in combined exposures, a significant increase in clearance rates was observed, indicating greater consumption of toxic cells in the presence of the antibiotic. This increase was 16% for 125 µgC L⁻¹ of M. aeruginosa combined with 0.3 µg L⁻¹ of AZT, and between 33.7% and 61.8% for 250 µgC L⁻¹ of M. aeruginosa combined with 0.3-3.0 µg L⁻¹ of AZT. These results suggest that azithromycin enhances the consumption of toxic cyanobacteria, increasing the risk of exposure to their toxins. Therefore, it is essential to investigate the combined effects of antibiotics and cyanobacteria on non-target species.

Endocrine-disrupting chemicals (EDCs) can interfere with hormone signalling, posing a significant risk to animal and human health. Usually, EDCs are environmental pollutants and, due to their lipophilic nature, can accumulate in fat tissues, leading to chronic exposure and serious health issues, such as endocrine-related neoplasia. Companion animals, particularly dogs and cats, are frequently exposed to EDCs at higher rates than their owners, owing to their proximity to the ground and their behaviours.

Despite increasing concern regarding EDC exposure, most biomonitoring studies to date have focused on humans and livestock, with limited attention given to pets. This study aimed to assess the presence of EDCs in the adipose tissue of dogs and cats diagnosed with hormone-sensitive neoplasms. Biological samples were collected from animals with and without neoplasia (i.e., a control group) at veterinary care centres across the north of Portugal. Clinical and pathological data, along with lifestyle information obtained through in-person questionnaires, were also gathered. A broad range of persistent and emerging EDCs were quantified using gas chromatography after a single ultrasound-assisted extraction (UAE) method was performed. Statistical data analysis was conducted to explore associations between EDC exposure and various clinical/pathological characteristics or animal habits. The findings from this research could provide valuable insights into the risks posed to pets by EDCs and support the development of improved strategies for the prevention, diagnosis, and treatment of endocrine-related diseases in companion animals.

Acknowledgements

This work received support and help from FCT/MCTES(LA/P/0008/2020-DOI 10.54499/LA/P/0008/2020, UIDP/50006/2020-DOI10.54499/UIDP/50006/2020 and UIDB/50006/2020-DOI 10.54499/UIDB/50006/2020), through national funds.