Journal of Xenobiotics最新文献

By the time of this study, Kiteezi landfill was Uganda's largest waste disposal site and received substantial volumes of municipal solid waste. In the present study, water (n = 36), leachates (n = 36), superficial sediments (n = 30), and Colocasia esculenta corms (n = 6) were sampled from Kiteezi landfill in the dry and wet seasons of 2022 before its tragic collapse in 2024. The physicochemical parameters (pH, electrical conductivity, temperature, and oxidation-reduction potential) and concentration of potentially toxic elements (As, Cu, Cr, Pb, and Zn) were analyzed using standard methods and inductively coupled plasma-optical emission spectrometry, respectively. Significant seasonal variations (p < 0.05) were observed for all the physicochemical parameters of water and leachates except temperature. Further, significantly higher concentrations (p < 0.05) of potentially toxic elements (PTXEs) were quantified in environmental matrices sampled during the dry season than the wet season. Arsenic and Pb concentrations in water surpassed their WHO permissible limit of 0.01 mg/L. The concentrations of PTXEs were higher in downstream samples (p < 0.05), indicating that landfill activities led to their enrichment in matrices near the facility. Ecological and pollution risk indices indicated that there is severe enrichment of Cu and Zn in the sediments, with dry season downstream samples having contamination factors and geoaccumulation indices of 539.3 and 74.7 and 8.5 and 5.6, respectively. Although ingestion of water may not cause probable health risks, consumption of Colocasia esculenta corms could lead to non-carcinogenic and cancer health risks in both children and adults (hazard indices = 0.085-189.0 and total cancer risk values of 7.33 × 10^-6-4.87 × 10^-3). These results emphasize the need that any new replacement for Kiteezi landfill should be properly planned and managed to mitigate potential environmental pollution with xenobiotics.

It is well known that environmental factors influence the risk of type 2 diabetes mellitus (T2DM). Several studies have linked the xenobiotics present in tobacco or air pollutants to T2DM development, although the underlying mechanisms remain unclear. Surfactant protein D (SP-D), an immune component released into the bloodstream after lung injury, has been associated with metabolic diseases. The aim of this study was to investigate whether SP-D mediates the effects of smoking or air pollution exposure on T2DM risk in the Spanish adult population. Socio-demographic, lifestyle (including smoking status) and clinical data from 2155 participants from the Di@bet.es cohort were analyzed. Annual concentrations of PM₁₀, PM_2.5, SO₂, CO and NO₂ according to participants' residential address codes were used to study air pollution exposure. T2DM was diagnosed at baseline and after 7.5 years of follow-up. SP-D serum levels were measured by ELISA and categorized as above or below the 25th percentile. Our results revealed a higher percentage of smokers in the high SP-D category; however, no associations were observed between air pollutants (PM₁₀, PM_2.5, SO₂, CO) and SP-D categories. Both smoking and elevated SP-D levels were found to increase the risk of T2DM independently. Mediation analysis indicated that SP-D mediates 14% of the effect of smoking on T2DM incidence in the Spanish adult population.

Recently developed quantitative structure-activity relationship (QSAR) prediction uses machine learning techniques with analytical signals from the full scan of mass spectra as input, and does not need exhaustive structural determination to assess unknown compounds. The QSAR approach assumes that a mass spectral pattern reflects the structure of a target chemical. However, the relationship between the spectrum and structure is complex, and requirement of its interpretation could restrict further development of QSAR prediction methods based on analytical signals. In this study, whether gas chromatography-electron-impact ionization-mass spectrometry (GC-EI-MS) data contain meaningful structural information that assists QSAR prediction was determined by comparing it with the traditional molecular descriptor used in QSAR prediction. Four molecular descriptors were used: ECFP6, topological descriptor in CDK, MACCS key, and PubChem fingerprint. The predictive performance of QSAR based on analytical and molecular descriptors was evaluated in terms of molecular weight, log K_o-w, boiling point, melting point, water solubility, and two oral toxicities in rats and mice. The influential variables were further investigated by comparing analytical-descriptor-based and linear regression models using simple indicators of the mass spectrum. The investigation indicated that the analytical and molecular descriptors preserved structural information differently. However, their performance was comparable. The analytical-descriptor-based approach predicted the physicochemical properties and toxicities of structurally unknown chemicals, which was beyond the scope of the molecular-descriptor-based approach. The QSAR approach based on analytical signals is valuable for evaluating unknown chemicals in many scenarios.

Permethrin (PERM) is a synthetic pyrethroid insecticide initially regarded as low risk. However, evidence now indicates that misuse and prolonged exposure can damage multiple physiological systems by disrupting enzymatic functions in subcellular structures. In this study, male Wistar rats were administered PERM (75, 150, or 300 mg/kg/day) for 15 days to assess its effect on hematological and biochemical parameters, including oxidative stress markers in the liver, kidney, and heart. Subacute PERM administration induced significant, dose-dependent toxicological alterations in exposed animals. Hematological analysis revealed impaired hematopoiesis, characterized by increased erythrocytes and platelets alongside decreased hemoglobin, hematocrit, mean corpuscular volume, and red cell distribution width. Biochemical analysis revealed elevated liver enzymes and bilirubin, along with reduced albumin levels, indicating hepatic alterations associated with PERM. The assessment of oxidative stress revealed tissue-specific responses following PERM exposure. While GPx, CAT, and SOD levels remained unchanged, GR activity increased in the heart, and GST activity increased in the liver. Additionally, a substantial decrease in MDA was observed in both the liver and heart. These collective alterations found in PERM-subacute exposed rats suggest the potential for cellular damage with the possible development of chronic pathologies, warranting further investigation.

Polycyclic aromatic hydrocarbons (PAHs) are toxic pollutants produced by the incomplete combustion of fuels and biomass. They are highly persistent and can accumulate in the food chain. Honey, a natural product susceptible to atmospheric deposition, has recently been recognized as an important bioindicator for monitoring environmental pollution. This systematic review examined 29 articles published from 2000 to 2025 analyzing the global presence, concentrations, and potential health risks of PAHs in honey. Results showed that the sum of polycyclic aromatic hydrocarbons (ΣPAHs) concentrations in honey ranged from below the detection limit to 166.83 µg/kg. Higher levels were observed in urban and industrial areas. Seventeen studies analyzed 16 PAHs prioritized by the US Environmental Protection Agency (EPA), with benzo[a]pyrene (BaP) being the most frequently detected, a highly toxic compound. Although most samples met international food safety standards, levels exceeding European regulatory limits were detected in some areas, raising concerns about local health risks. The results of this study emphasize the need for standardized analytical methods and routine monitoring to more accurately assess the exposure risk of PAHs in honey.

People are exposed to mixtures of metals, per- and polyfluoroalkyl substances (PFAS), phthalates, and polycyclic aromatic hydrocarbons (PAH) rather than single chemicals, yet mixture inference is hampered by high dimensionality, correlation, missingness, and left-censoring below limits of detection (LOD). We analyzed 2013-2014 National Health and Nutrition Examination Survey (NHANES) biomarkers (n = 4367) to (i) recover latent, interpretable co-exposure structures and (ii) quantify how these mixtures relate to liver health. To denoise and handle censoring, we applied Principal Component Pursuit with LOD adjustment (PCP-LOD), decomposing the exposure matrix into a non-negative low-rank component (population co-exposure profiles) and a sparse component (individual spikes), and then used Bayesian Kernel Machine Regression (BKMR) to estimate nonlinear and interactive associations with AST, ALT, GGT, ALP, total bilirubin, and the Fatty Liver Index (FLI), retaining analytes with ≥50% detection. PCP-LOD revealed coherent clusters (e.g., long-chain PFAS grouping; shared metal loadings), while the sparse layer highlighted episodic phthalate elevations. BKMR indicated outcome-specific mixture effects: PAHs and selected phthalates showed consistently positive associations with ALP, GGT, and FLI; PFAS (PFOS, PFNA, PFOA) exhibited modest associations with ALP and bilirubin; metals displayed mixed directions. A joint increase in the overall mixture from the 25th to 75th percentile corresponded to an upward shift in FLI and a smaller rise in ALT. This censoring-aware low-rank-plus-sparse framework coupled with flexible mixture modeling recovers actionable exposure architecture and reveals clinically relevant links to liver injury and steatosis, motivating longitudinal and mechanistic studies to strengthen causal interpretation.

Ficopomatus enigmaticus, a reef-forming serpulid, has emerged as a promising candidate for biomonitoring and ecotoxicology studies. Recent research has focused on adult stress responses, highlighting the need to understand population-specific responses. This study employed a multi-biomarker approach to investigate how F. enigmaticus adults from two populations in the NE Adriatic (Site A) and NE Tyrrhenian (Site B) responded to chronic exposure to heat and chemical stress (dimethyl sulfoxide, DMSO), individually and in combination. The analysis detected significant differences in protein content and the activities of superoxide dismutase (SOD) and glutathione S-transferase (GST) between populations. Notably, no oxidative damage (measured as lipid peroxidation, LPO) was detected in any population or treatment. Similarly, no significant differences were detected in the integrated biomarker response index (IBRv2i). However, lower IBRv2i values at Site A suggested reduced stress conditions, possibly indicating that this site may have lower baseline stress. Overall, treatment effects were limited and site-specific: only the combined heat and DMSO exposure at Site A lowered GST activity compared to heat stress alone. Nevertheless, both populations exhibited broadly similar biochemical response patterns to stress. Our findings deepen the understanding of stress physiology in F. enigmaticus, underscoring the ecological importance of multi-stressor approaches in environmental monitoring.

Bisphenol A (BPA) is a synthetic estrogen widely used in the manufacture of food packaging materials, raising concerns due to its potential migration into food products. This study aims to determine BPA levels in pasteurized milk marketed in Algeria, using an easy-to-handle and efficient liquid-liquid extraction method coupled with liquid chromatography and fluorescence detection. A total of 30 pasteurized milk samples packaged in plastic were analyzed. The method validation demonstrated excellent linearity, with a limit of detection of 3.76 µg/L and a limit of quantification of 11.40 µg/L. Among the analyzed samples, 17 contained detectable BPA levels, ranging from not detectable to 24.07 µg/L, with an average concentration of 3.77 ± 5.77 µg/L, compliant with European regulation. The health risk assessment, based on estimated chronic daily intake and hazard index, indicated no significant risk associated with BPA exposure through milk consumption in the studied population. Additionally, the estrogenic equivalence of BPA in milk was 6.032 × 10^-5 µgE₂/L, confirming a low estrogenic activity.

The eutrophication of aquatic ecosystems often triggers the excessive growth of cyanobacteria, many of which release toxic metabolites such as microcystins (MCs). When irrigation water is contaminated by these compounds, adverse consequences may arise for plants as well as for animal and human health. In contrast, certain non-toxic cyanobacterial species like Limnospira platensis are increasingly regarded as valuable tools for sustainable agriculture, given their ability to enhance plant nutrition, growth, yield, and stress tolerance while also mitigating the detrimental impacts of MCs. The present work aimed to investigate the potential of L. platensis extract to enhance growth, physiological responses, and tolerance of radish (Raphanus sativus) plants stressed with Microcystis aeruginosa extract containing microcystins. Experiments were conducted in a hydroponic system under controlled environmental conditions, where radish seedlings were cultivated in perlite and exposed for 45 days to M. aeruginosa extract (10 and 40 µg/L of MCs) and L. platensis extract (0.1 and 1 g/L), applied either separately or in combination. The results showed that the application of L. platensis extract, especially at 1 g/L in combination with 40 µg/L of MCs, decreased the bioaccumulation of MCs from 8.81 to 5.35 µg/kg FW in the leaves and from 14.64 to 10.15 µg/kg FW in the taproots. In addition, it significantly stimulated radish growth and improved several biochemical parameters. In contrast, exposure to MCs at 10 and 40 µg/L negatively affected growth, chlorophyll pigments and protein contents while promoting the accumulation of malondialdehyde (MDA), polyphenols and sugars. The activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT) were also increased under MCs stress, suggesting activation of the antioxidant defense system in response to oxidative damage. Combinations of MCs with L. platensis extract, especially at 1 g/L, improved antioxidant enzyme activities by significantly reducing MDA levels, biometric parameters, chlorophyll pigment, and protein and sugar contents. These results indicate that the application of L. platensis extract as a biostimulant can improve radish development, growth, and tolerance to MC-induced stress.

Plastic pollution represents a significant emerging environmental problem. Micro-sized particles of synthetic polymers-microplastics (MPs)-have been identified in all parts of marine ecosystems. In the marine environment, organisms are exposed to MPs, which undergo a constant process of physicochemical and biological degradation. Utilization of UV irradiation as the optimal exposure factor in the simulation of fundamental natural conditions is a widely accepted approach. This enables the study of the harmful effects of such particles when interacting with aquatic organisms. This study aimed to investigate the effect of pristine and photoaging primary polystyrene microspheres (µPS) at three concentrations on the viability and DNA integrity of the sperm of the sand dollars Scaphechinus mirabilis. The results of the investigation demonstrated that IR spectroscopy revealed structural changes in polystyrene, confirming the oxidative degradation of the polymer under UV irradiation. The study demonstrated that artificially aged µPS exhibited a more pronounced effect than pristine particles, as evidenced by reduced sperm viability and increased DNA damage. Thus, the resazurin test showed that after exposure to UV-irradiated µPS, sperm viability decreased to 83-85% at concentrations of 10 and 100 particles and to 70% at a concentration of 1000. In addition, the Comet assay showed that the particles increased the percentage of DNA in the tail from 20% to 30% in a dose-dependent manner. The findings substantiate and augment the existing body of experimental data of the toxicity of aged plastic fragments, thereby underscoring the need for further study into the toxicity of aged MPs on marine invertebrates.