Search Results (348)

Terrestrial snails are recognised as bioindicators of environmental contamination and may represent a source of dietary exposure to persistent organic pollutants (POPs). However, data on polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs), and polychlorinated biphenyls (PCBs) in edible land snails remain limited. This study investigated PCDD/Fs, dioxin-like PCBs (dl-PCBs), and non-dioxin-like PCBs (ndl-PCBs) in the foot muscle and hepatopancreas of free-living Helix pomatia (H. pomatia) collected from two regions of Poland. A total of 48 snails (24 per region) were analysed as three pooled replicates per tissue type in each region. Thirty-five congeners were determined using high-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC-HRMS). Overall, only trace concentrations of selected PCDFs and dl-PCBs were detected, exclusively in hepatopancreas samples. Among PCDFs, only 2,3,7,8-TCDF and 1,2,3,7,8-PeCDF were quantified, whereas PCB 77 was the only quantified dl-PCB congener. All analysed PCDD congeners and ndl-PCBs were below the limit of quantification. TEQ values calculated using 2005 WHO-TEFs remained very low in all analysed samples, including under the upper-bound approach. The preferential detection of contaminants in the hepatopancreas was consistent with the higher lipid content of this tissue. The results indicate very low contamination of H. pomatia with dioxins and PCBs and low toxicological relevance under the investigated conditions. Full article

Commonly occurring polychlorinated biphenyls (PCBs) in the environment have been linked to a broad range of adverse toxicological effects in both animals and humans. In this study, in vitro, in silico, and in vivo models were used to investigate the surface interactions of PCBs with green-engineered clays (GECs). Earlier studies showed that these GECs significantly reduced the toxicities of important planar aromatic chemicals such as benzene and aflatoxin B₁ along with ochratoxin A, a chlorinated aromatic chemical. The overall objective for this study was to show that GECs could tightly adsorb PCBs, resulting in a decrease in toxicity of a commercial PCB mixture (Aroclor 1260). Gastrointestinal pH and temperature were simulated in vitro, and the clay surface binding interactions of six PCBs were characterized using isothermal analyses. Molecular dynamics (MD) simulations were employed to provide atomistic understanding into PCB congener interactions with parent and chlorophyll-amended clays. To confirm the ability of GECs to protect a living organism, Aroclor 1260 was investigated using a well-established hydra bioassay. According to simulations, coplanar PCBs had an increased probability of binding to parent clay compared to non-coplanar ones, in line with experiments, due to their ability to lay flat on the clay surface. Chlorophyll amendments enhanced binding of all PCBs according to both experiments and computations. Within the simulations, chlorophyll amendments facilitated both coplanar as well as non-coplanar PCBs to directly bind to the clay and additionally interact with chlorophyll amendments, as well as to bind to chlorophyll amendments without necessarily interacting with the clay. Aroclor 1260 caused irreversible damage to hydra. At 0.05% inclusion, parent clay offered limited protection (20%) while GECs offered 55% to 65% protection, showing the advantage of GECs over parent clays. The findings of this study indicate that edible GECs adsorb PCBs, with the highest sorption associated with the coplanar congeners. Further studies are warranted to determine the application of GECs as potential disaster-response supplements in the diet to reduce the bioavailability of PCBs from contaminated food and water, especially following floods and other emergencies. Full article

Environmental exposure to persistent and non-persistent endocrine-disrupting chemicals (EDCs), including per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs), dioxins, phthalates, and bisphenols, has been increasingly associated with elevated cardiovascular disease (CVD) risk. Emerging evidence suggests the importance of gene–environment interactions in modulating individual susceptibility to EDC-related cardiovascular effects. This review summarizes current knowledge by synthesizing the main classes of EDCs, evaluating the evidence linking them to cardiovascular outcomes, and highlighting how genetic variability may modulate EDC-induced cardiovascular risk. Across the studies analyzed, the most extensively investigated genetic polymorphisms involve pathways related to oxidative stress regulation, xenobiotic metabolism and detoxification, hormone signaling, and lipid homeostasis. Variants in antioxidant defense genes, such as CAT, eNOS, and PON1, have been associated with increased hypertension risk and vascular dysfunction following exposure to bisphenols and PAHs. Polymorphisms in GSTP1, CYP2C19, CYP1A2, CYP2E1, ABCB1, and MTHFR may influence susceptibility to cardiometabolic alterations and congenital heart defects, whereas variants in ESR2, FTO, LEPR, and INSIG2 have been linked to obesity, dyslipidemia, and hypertension associated with PFAS, PBDEs, and bisphenols. A deeper understanding of gene–environment interactions is essential to advance preventive cardiology and mitigate the cardiovascular impact of environmental pollutants. Full article

Introduction: Aquatic ecosystems are major reservoirs for both legacy and emerging contaminants, facilitating their distribution throughout the environment and bioaccumulation across different trophic levels. As such, wildlife acts as a valuable tool for biomonitoring these contaminants and serves as a key indicator of environmental pollution within the One Health framework. Despite this, knowledge regarding the application of this framework alongside the assessment of aquatic contaminants using wildlife species remains fragmented. Objective: This study aims to synthesize current evidence on aquatic contaminants using wildlife as sentinels of environmental pollution and to explore how the One Health concept is applied in this field. Methodology: A systematic database search was conducted in SCOPUS, and the retrieved studies were screened according to predefined inclusion and exclusion criteria, as well as their relevance to the One Health concept. Results: Despite its timely relevance, only fourteen studies have adopted the One Health approach to assess contaminants in aquatic species. The selected studies focused mainly on plastic particles (53.33%), such as macro- and microplastics; heavy metals (26.67%), such as mercury (Hg), cadmium (Cd), Nickel (Ni), lead (Pb), and selenium (Se); persistent organic pollutants (13.33%), such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), per- and polyfluoroalkyl substances (PFAS), and dioxin/furans; and metalloid (6.67%) arsenic (As). These contaminants were evaluated across four different taxonomic groups: fishes (61.54%), waterbirds (23.08%), mollusks (7.69%) and crustaceans (7.69%). Most studies were conducted in Portugal (37.5%) and the United States of America (18.75%), whereas other countries, including Canada, Australia, Ecuador, Mexico, Indonesia, and Turkey, were mentioned in only one study each (6.25%). Conclusions: Monitoring levels of contaminants in wildlife is essential not only to understand the dynamics of environmental pollution, but also to preserve the integrity of ecosystems while safeguarding animal and human health. However, the limited number of studies adopting a One Health perspective results in an incomplete representation of contaminant classes and affected taxa. These findings highlight the urgent need to expand wildlife-based monitoring strategies within a One Health framework, aiming to improve environmental risk assessment and deepen our understanding of the impacts of pollution across ecosystems, animals and humans. Full article

Background/Objectives: Polychlorinated biphenyls (PCBs) are persistent environmental contaminants associated with chronic toxicity and neurological dysfunction. PCB 153 is among the most prevalent congeners detected in environmental and dietary matrices. Although transcriptional responses to PCB 153 have been described, its potential association with post-transcriptional regulation remains poorly defined. Here, we performed an exploratory computational RNA-seq splicing analysis of previously generated transcriptomic data from retinoic acid-differentiated SH-SY5Y cells exposed to a sub-cytotoxic concentration of PCB 153. Methods: RNA-seq data were analyzed to identify candidate differentially alternative splicing events (DASEs). Candidate events were further examined for retained intron (RI)-related premature termination codons (PTCs), and potential regulatory interactions, including DASE-RNA-binding protein (RBP) motif enrichment. Results: PCB 153 exposure was associated with differential expression of 32 RNA-binding protein (RBP) encoding genes and with 90 candidate DASEs. Disease enrichment analysis indicates that genes affected by candidate splicing alterations overlapped with gene sets annotated to intellectual disability and related neurodevelopmental phenotypes. Among retained intron events, several were predicted to introduce PTCs, suggesting potential effects on transcript stability or coding potential. Motif enrichment analysis identified positional enrichment of motifs corresponding to CELF2, NUMA1, PRPF8, and RBM22 within DASE-associated regions, nominating these RBPs as putative regulators associated with the observed splicing alterations. Conclusions: This computational study identifies candidate PCB 153-associated splicing alterations and RBP-related regulatory hypotheses in a neuron-like in vitro model, suggesting a potential mechanistic link between PCB 153 and neurodevelopmental dysfunction. Full article

Invasive alien species (IAS) such as Silurus glanis and Procambarus clarkii represent major ecological threats but may also serve as effective bioindicators of environmental contamination; therefore, this study aimed to evaluate their potential for multi-contaminant monitoring and assess their suitability as alternative feed and food resources within a circular economy framework. Multi-contaminant profiles were investigated in S. glanis and P. clarkii from Avigliana Lakes (NW Italy), analyzing trace elements, rare earth elements (REEs), and organic contaminants in fish muscle, and microplastics (MPs) in intestinal tracts. In S. glanis, total trace element concentrations and ΣREEs were markedly higher in Small Lake than in Great Lake, with ΣREEs reaching 0.445 and 0.056 mg/kg w.w., respectively. Mean concentrations of the regulated elements in Great Lake were 0.017 mg/kg w.w. (As), 0.003 mg/kg w.w. (Cd), and 0.16 mg/kg w.w. (Pb), increasing in Small Lake to 0.19, 0.03, and 1.86 mg/kg w.w., respectively. In P. clarkii, contamination levels were lower, with ΣREEs averaging 0.074 mg/kg w.w. and mean concentrations of As, Cd, and Pb of 0.25, 0.006, and 0.21 mg/kg w.w., respectively. Organic contaminants, including polycyclic aromatic hydrocarbons (PAHs), non-dioxin-like polychlorinated biphenyls (NDL-PCBs), and pesticides, were generally below limits of quantification. MPs were detected in 100% of specimens, with mean concentrations of 4.2 ± 2.15 and 4.4 ± 2.70 MPs per intestinal tract in S. glanis (Great and Small Lake, respectively) and 2.7 ± 2.39 MPs/intestinal tract in P. clarkii. Permutational multivariate analysis of variance (PERMANOVA) indicated significant site-related differences in S. glanis and species-related differences between S. glanis and P. clarkii within Great Lake. Most regulated contaminants were below applicable EU thresholds; however, Pb in S. glanis from Small Lake exceeded the maximum level established for fish muscle intended for human consumption. Full article

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants associated with neurodevelopmental and neurodegenerative disorders. PCB 118 is one of the most abundant congeners and exerts neurotoxic effects, yet the molecular mechanisms underlying its impact on human neurons remain poorly understood. We investigated the molecular response of retinoic acid-differentiated, neuron-like SH-SY5Y cells exposed to 5 µM PCB 118 for 24 h, a concentration that did not affect cell viability. RNA sequencing identified 1239 differentially expressed genes. Functional enrichment and protein-protein interaction analyses identified upregulation of histone and chromatin structural genes, indicative of substantial chromatin remodeling. In parallel, a significant downregulation of genes involved in ribosome biogenesis and rRNA processing was observed, potentially indicating impairment of the protein synthesis machinery. These transcriptional changes point to a coordinated reprogramming of nuclear architecture and translational machinery, potentially compromising neuronal homeostasis. The modulation of proteostasis-related pathways further supports a mechanistic link between PCB 118 exposure and neuronal dysfunction. Our results provide a comprehensive transcriptional framework connecting PCB 118 to chromatin-mediated gene regulation and suppression of ribosome biogenesis in human neuron-like cells. This study offers mechanistic insights into how environmental PCB exposure may contribute to neurotoxicity and highlights molecular pathways potentially implicated in the development of neurodegenerative disorders. Full article

Sustainable fish resources are essential for ecological and economic stability, yet many freshwater species accumulate toxic contaminants that threaten human health, the environment and regional economies. This study analyzes a multi-variable dataset from the Michigan Fish Contaminant Monitoring Program, containing variables across numerous species and including key pollutants such as mercury, perfluorooctane sulfonic acid (PFOS), polychlorinated biphenyl (PCB), and toxaphene. After rigorous preprocessing, including missing-value treatment, outlier removal using the 3-sigma rule, and z-score standardization, principal component analysis (PCA) was applied to characterize contamination patterns. The PCA revealed that the first three components explain approximately 78.37% of total variance, with PC1 reflecting overall contamination and fish morphometric variables (length and weight), while contaminants contribute to secondary variation across PC2 and PC3. These statistically derived contamination regimes highlight biophysical pressures that carry economic consequences. The findings illustrate how multivariate statistical methods can inform ecological and environmental economic assessments, identifying pollution pathways and supporting circular-economy strategies aimed at reducing contaminant inputs, improving resource efficiency, and safeguarding economically and ecologically valuable fish populations. Full article

Persistent organic pollutants such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) remain a public health concern due to their persistence, bioaccumulation, and potential health effects. Human breast milk is an important biomonitoring matrix for assessing maternal and infant exposure to lipophilic contaminants. This pilot study aimed to determine concentrations of PCDD/Fs, dioxin-like PCBs (dl-PCBs), and non-dioxin-like PCBs (ndl-PCBs) in breast milk samples collected from five lactating women residing in the Greater Poland Province and to explore potential determinants of exposure. Following participant recruitment, sample collection, and questionnaire-based assessment performed by the authors, breast milk samples were analyzed at the accredited Laboratory of Trace Analysis (Cracow University of Technology, Poland) using isotope dilution gas chromatography coupled with tandem mass spectrometry. Toxic equivalency values (TEQ) were calculated using World Health Organization 2005 toxic equivalency factors (WHO-TEFs). WHO-PCDD/F-TEQ ranged from 0.096 to 0.22 pg/g fresh weight. Median lipid-normalized WHO-PCDD/F-TEQ and total WHO-PCDD/F-PCB-TEQ concentrations were 3.5 and 4.7 pg/g lipid, respectively, remaining below the European Food Safety Authority (EFSA) reference level of 5.9 pg/g lipid; only one sample exceeded this threshold (6.2 pg/g lipid). Lipid-normalized WHO-PCB-TEQ correlated positively with maternal age (ρ = 0.949, p = 0.0389). The observed values were within the lower range reported in recent European studies. The congener patterns suggest a combination of chronic exposure to combustion by-products and long-term bioaccumulation of historical industrial pollutants. Although limited by the small sample size, this exploratory study provides preliminary regional biomonitoring data supporting future environmental exposure research. Full article

Polychlorinated biphenyls (PCBs) persist in the environment as complex mixtures and undergo extensive biotransformation, yet the developmental toxicity of PCB metabolites remains poorly defined. We evaluated developmental, neurobehavioral, and molecular effects of parent PCBs, hydroxylated, methoxylated, and sulfated metabolites, and environmentally relevant mixtures using embryonic zebrafish. This study employed a high-throughput screening approach using nominal exposure concentrations to enable rapid hazard identification and prioritization across a large chemical series. Morphological abnormalities and photomotor behavior were assessed across early development, followed by targeted cyp1a reporter analysis and transcriptomic profiling for a subset of potent exposures. Most chemicals induced morphological effects, with hydroxylated and sulfated metabolites producing effects more frequently and at lower benchmark concentrations than parent congeners. Behavioral alterations were more prevalent in embryonic photomotor response than larval photomotor response and generally co-occurred with morphological effects. Environmental mixtures elicited broad phenotypic profiles comparable to highly active individual compounds. Transcriptomic analyses revealed minimal responses for parent PCBs but robust, exposure-specific gene expression changes for select metabolites, particularly 5-OH-PCB11, and mixtures. Differentially expressed genes were enriched for xenobiotic metabolism, immune signaling, and neuroactive pathways, alongside consistent downregulation of circadian regulators. Together, these results demonstrate contributions of PCB metabolites and mixtures to toxicity. Full article

Quantifying the mixture effects on humans exposed remains challenging because mixture components are correlated and may act bidirectionally by exhibiting nonlinear dose-response relationships, which may contribute to subclinical organ dysfunction. The liver is a vital organ in the body with broad functions, making it vulnerable to injury as it is the first organ exposed to circulating toxicants, which can precipitate hepatic damage. Our study’s objective was to evaluate the combined and component-specific associations of a multi-chemical exposure mixture of heavy metals, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (dioxins), and polychlorinated dibenzofurans (furans), with liver biomarkers, and to compare concentration-based results with the toxic equivalent (TEQ) potency of the weighted results for dioxin-like compounds. In an unweighted analytic sample of U.S. adults from NHANES 2003–2004 with 947 complete cases, we examined heavy metals (cadmium, lead, and mercury), PCBs (12 congeners), dioxins (7 congeners), and furans (10 congeners) in relation to eight liver biomarkers (albumin, ALP, ALT, AST, GGT, LDH, total bilirubin, and total protein). We applied multi-exposure linear regression, weighted quantile sum (WQS) regression, quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR), with parallel TEQ-based models using WHO 2005 TEFs for dioxin-like PCBs, dioxins, and furans. Across mixture methods, the mixture structure was chemically sparse, with a limited set of recurring contributors. Total bilirubin showed the most consistent positive mixture association across qgcomp and BKMR and persisted under TEQ weighting, with prominent PCB- and dioxin-like contributions (notably PCB81/PCB TEQs and dioxin-related components). Albumin demonstrated inverse mixture patterns in BKMR and TEQ-BKMR, with dioxin-like components (notably Dioxin3 and Dioxin3_TEQ) repeatedly emerging as key drivers. For ALT, ALP, AST, GGT, LDH, and total protein, overall mixture effects were frequently attenuated or null in qgcomp despite structured component weights, indicating bidirectional sub-mixtures and internal counterbalancing. BKMR PIPs similarly concentrated on a small number of dominant predictors (e.g., lead for ALP, mercury for ALT, PCB28 for AST, and cadmium and PCB189 for LDH), while interaction summaries provided limited evidence of stable non-additivity. Using multiple complementary mixture methods, we identified outcome-specific mixture patterns suggesting hepatobiliary vulnerability. TEQ concordance supports toxicological relevance of the dioxin-like axis, while metals and non–dioxin-like mechanisms likely contribute additional pathways. Full article

Polychlorinated biphenyls (PCBs) remain a major concern in marine ecosystems, where bioaccumulation in fish occurs as complex congener mixtures whose dynamics challenge conventional indicator approaches. This study develops and evaluates a data-driven framework for refining mixture-based indicators of PCB contamination by integrating ensemble machine learning with explainable artificial intelligence. Focusing on PCB-138 as a target indicator of cumulative PCB burden, we analyse concentrations of 24 organochlorines together with biological covariates in four Mediterranean edible pelagic fish species (sardine, anchovy, horse mackerel, and chub mackerel). Comparative evaluation of indicator performance shows that alternative congener combinations, including i4 PCBs (-138, -153, -170, -180), i6 PCBs (-138, -153, -170, -180, -118, -123), and mixtures incorporating DDD and DDE, more effectively represent total PCB burden than traditional indicator groups. Clustering identifies two distinct bioaccumulation settings, characterized by high-concentration coherent congener effects and low-concentration heterogeneous responses, demonstrating that indicator performance depends on concentration range and mixture context. The study illustrates how interpretable machine learning approaches can serve as formal tools for indicator evaluation and optimisation, strengthening long-term monitoring and management of legacy contaminants in marine ecosystems, particularly under conditions of persistent exposure and renewed inputs from sediment remobilization and riverine transport. Full article

Toxic environmental contaminants, such as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and polychlorinated biphenyls (PCBs) occur differentially in animal tissues. This study examined paired liver and muscle tissues from the same animals, reducing the uncertainty inherent in other studies that source tissues from different animals. Investigations were carried out on cattle and sheep from two separate herds in Southern Italy. As all animals experienced the same environmental impacts, husbandry, and feed regimes, contaminant distribution between tissues would result from physiological considerations, which would also allow for better examination of the effects of age. In both investigations, PCDD/F and PCB concentrations were significantly higher (p < 0.01) in the liver relative to muscle. A characteristic occurrence pattern showed PCBs dominating the combined toxic equivalence (TEQ) by >95% in cattle tissues and 78% and 67% in sheep muscle and liver, respectively. A majority of liver samples exceeded regulated maximum limits, and the herds were excluded from the food supply. Subsequent regional monitoring showed regulatory compliance of cattle/sheep meat and liver, but prominence of PCB-TEQ persisted. Concentrations of both contaminants declined strongly in the tissues of both species with increasing age of juveniles but stabilized in older animals (>one year in sheep; 2/3 years in cattle). Although weight gain might partly account for this pattern, the initial decline may also relate to inadequate levels of CYP enzymes in the youngest juveniles, but this would need to be confirmed in both species by targeted toxicokinetic studies during this perinatal period. The expression of these detoxifying enzymes is reported to rise rapidly with increasing postnatal age in many animal species, including sheep. Full article

This study evaluated contamination by polychlorinated dibenzodioxins and dibenzofurans (PCDDs/Fs) and polychlorinated biphenyls (PCBs) in 390 feeds and 1756 food samples collected in Latium and Tuscany (Italy, 2016–2025) using HRGC-HRMS. PCDDs/Fs and dioxin-like PCBs (dl-PCBs) are expressed as WHO 2005 toxic equivalents (WHO₀₅-TEQ). Non-dioxin-like PCBs (ndl-PCBs) lack dioxin-like toxicity mechanisms due to their non-coplanar structure and are not assigned a toxic equivalence factor. Feed results were normalised to 12% moisture content. Median levels of WHO₀₅-PCDDs/Fs+dl-PCBs TEQ at the upper limit in feed were 10–100 times lower than those reported in European monitoring data (EFSA, 2002–2010) for comparable categories, including additives, premixtures, raw materials and compound feed, with plant and animal feed materials below 0.03 ng/kg and aquaculture feed at 0.24 ng/kg. Food contamination was generally low, with the median WHO₀₅-PCDDs/Fs+dl-PCBs TEQ 2–4 times lower than Italian national data (2013–2016), considering comparable categories such as meat, fish, milk, eggs, oils, baby foods, marine oils, animal fats and liver. Higher levels were observed in game meat, sheep products and fermented milk than in pork and poultry. The contamination remained stable over time. These results indicate an improvement in food safety thanks to national and EU regulations, although continued surveillance of high-risk and undersampled categories remains essential. Full article

The Kupa River (Croatia), a tributary of the Danube basin forming part of the Slovenian border, was heavily contaminated with polychlorinated biphenyls (PCBs) between 1962 and 1985 due to improper handling and downstream transport via the Krupa and Lahinja rivers. This study evaluated the occurrence, interspecific distribution, and human health implications of PCBs and polycyclic aromatic hydrocarbons (PAHs) in fish (Northern pike, Common carp, Grass carp, Pike-perch, Wels catfish, Bream, and Chub) from the Croatian Kupa River. PCB concentrations were consistently higher than PAH levels across all species. In 30% of samples, Σ6 non-dioxin-like PCBs exceeded the European Commission maximum permissible level for freshwater fish (125 ng⋅g⁻¹ wet weight). Of the 11 PAHs analyzed, only fluoranthene and pyrene were detected. Self-Organizing Map identified distinct pollutant patterns, with chub showing the highest variability and accumulation. PCB concentrations position the Kupa River among moderately to highly impacted European freshwater systems affected by legacy industrial contamination. Health risk assessment, incorporating updated national consumption data, indicates that long-term, uncontrolled consumption of Kupa River fish may pose risks due to PCB exposure, while PAH-related risks appear negligible. These findings highlight the persistence of legacy PCB pollution and the need for integrated sediment–biota monitoring. Full article