Search Results (439)

The aim of this study was to evaluate the concentration of polychlorinated biphenyls (PCBs) in chinstrap penguins (Pygoscelis antarctica) and krill (Euphausia superba) from Deception Island (South Shetland Islands, Antarctica) to provide additional data of the PCB presence in Antarctica. To this end, 34 samples of different tissues corresponding to four adult specimens and six chicks, and krill from the area were studied. The selected samples were analyzed for the determination of 27 congeners of PCBs by gas chromatography. Adult specimens accumulated PCBs mainly in the liver (33%, 1330.82 ± 733.69 pg·g⁻¹ wet weight, w.w.) and muscle (25%, 1029.73 ± 823.4 pg·g⁻¹ w.w.), whereas the brain showed the highest levels in chicks (36%, 1215.83 ± 955.19 pg·g⁻¹ w.w.). Regarding krill, our results were five to eight times lower than the levels found in krill from King George Island and from the Ross Sea. Further, a distribution analysis of PCBs in penguins according to Regulation 2013/39/UE and Commission Regulation (EU) No 277/2012 was also performed, and PCBs were categorized into three groups (dioxin-like-mono-ortho, non-dioxin-like-indicators, and others-non-dioxin-like). The data indicate that the content of the other group was generally higher than that of the other two PCB groups for both adults and chicks. Notably, the liver consistently exhibited the highest proportion of the other group. Full article

Background/Objectives: Exposure of high-fat diet (HFD)-fed mice to polychlorinated biphenyls (PCBs) results in metabolic dysfunction-associated steatotic liver disease (MASLD) and progression to metabolic dysfunction-associated steatohepatitis (MASH). The mechanisms by which HFD diet and PCBs increase MASLD are unclear. Previously, we identified differences in HFD-fed mouse liver tRNA modifications with single oral exposures to the dioxin-like PCB126, the non-dioxin-like PCB mixture Aroclor 1260 (Ar1260), or the combination of Ar1260 + PCB126. Methods: Here, we used small RNA sequencing and the tRNA analysis of expression (tRAX) pipeline to examine if PCB exposures alter the tRNA transcriptome, including tRNA-derived fragments (tRFs), in the livers of the PCB-exposed mice. Results: Each PCB exposure produced distinct hepatic tRNA transcriptomes with more tRNAs decreased than increased. Only tRNA-Glu-TTC-1 was reduced with all three PCB exposures. More changes in tRFs were identified with Ar1260 alone or in combination with PCB126 than with PCB126 alone. Four tRF-3s were upregulated in both PCB126 and Ar1260 + PCB126 co-exposed mice, suggesting PCB126 as responsible for this increase. We previously reported that PCB126 exposure increased hepatic Angiogenin (ANG) protein which generates tRF-3s. Four previously reported tRNA modifications corresponded to positions of PCB-associated tRNA modifications identified by tRAX: m1A, m6A, ms2t6A, and Ψ. Conclusions: Overall, the differences in hepatic tRNAs and tRFs with three different PCB exposures suggest that PCB exposures play an unexplored role in regulating translation in mouse liver. Full article

Worldwide, the healthcare industry produces massive quantities of medical waste (MW), most of which is incinerated, releasing large quantities of dioxins, mercury, and other pollutants. Despite this, only a limited number of studies have explored the incorporation of MW into construction materials, with a special focus on cement-based construction materials (CB-CMs). However, to the best of the authors’ knowledge, no existing review formally structures, summarizes, correlates, and discusses the findings of previous studies on MW in CB-CMs to encourage further research and applications of this promising alternative. Therefore, the added value of this study lies in providing an innovative and critical analysis of existing research on the use of MW in CB-CMs, consolidating and evaluating dispersed findings through a systematic literature review, enhancing understanding of the topic, and identifying knowledge gaps to guide future research. A robust systematic literature review was conducted, encompassing 40 peer-reviewed research articles, retrieved from the Web of Science Core Collection database. The methodology involved a three-stage process: a descriptive analysis of the included articles, the identification and synthesis of key thematic areas, and a critical evaluation of the data to ensure a rigorous and systematic report. The selection criteria prioritized peer-reviewed research articles in English with full text availability published in the last 7 years, explicitly excluding conference papers, book chapters, short reports, and articles not meeting the language or accessibility requirements. The results indicate that the influence of MW in CB-CM varies significantly. For example, while the incorporation of face masks as fiber reinforcement in concrete generally enhances its mechanical and durability properties, the use of gloves is less effective and not always recommended. Finally, it was found that further research is needed in this field due to its novelty. Full article

Polychlorinated biphenyls (PCBs) are classified as persistent organic pollutants (POPs) due to their potential threat to both ecosystems and human health. The Tibetan Plateau (TP), characterized by its low temperatures, pristine ecological conditions, and remoteness from anthropogenic influences, serves as the investigation region. This study analyzed water samples from the temperature glacial watershed and employed the risk assessment method established by the United States Environmental Protection Agency (US EPA) to assess both carcinogenic and non-carcinogenic risks of PCBs in five age groups. The total concentrations of PCBs (∑₃PCBs) varied from 738 to 1914 ng/L, with a mean value of 1058 ng/L, which was comparable to or exceeded levels reported in the surface water around the TP. Notably, the riverine sites located near the villages and towns exhibited the highest pollution levels. Our analyses indicated that glacier melting, long-range atmospheric transport (LRAT), reductive dechlorination processes, and various anthropogenic activities might be potential sources of PCB emission in the Meili Snow Mountains. According to the established national and international water quality standards, as well as toxic equivalency concentrations (TEQs) for dioxin-like PCBs (DL PCBs), the PCB concentrations detected in this study could result in serious biological damage and adverse ecological toxicological effects. However, the PCBs in all samples posed a negligible cancer risk to five age groups, and a non-carcinogenic risk to adults. These findings contribute valuable insights into the risks and sources of PCBs and may serve as a foundational reference for subsequent study of these compounds in the Meili Snow Mountains area of the southeastern TP. Full article

The rapid growth of the world’s population is generating escalating demands for food production. Global food demand is expected to increase by 35% to 56% between 2010 and 2050. Therefore, food mass production is becoming more challenging. The chemicalization of food production, processing, transport, packaging, and storage is almost impossible to avoid. These factors, along with environmental pollution, contribute to the increase in food product contamination. Xenobiotics appearing in food, including a variety of toxic substances (heavy metals, acrylamide, polycyclic aromatic hydrocarbons), and pathogens (pathogenic bacteria, fungi, molds, and yeast-producing mycotoxins) can threaten consumers’ safety and have negative economic implications. In this regard, the introduction of effective detoxification methods appears to be very important. It can be accomplished by physical, chemical, and biological means. Many reports have proved that probiotics are useful in food biodetoxification. Probiotics effectively reduce food contamination (at various stages of food production) and, moreover, annihilate toxins present in the human body. Many in vitro studies have confirmed the biodetoxification properties of probiotics, demonstrating that they diminish the toxic effects of the main types of food contaminants (heavy metals, polycyclic aromatic hydrocarbons, pesticides, mycotoxins, nitrates and nitrites, acrylamide, alkylphenols, biogenic amines, and dioxins). Probiotics produce various bioactive compounds, including antimutagenic, antioxidant, and anti-carcinogenic compounds. Their protective and beneficial influence on human microbiota can modulate host inflammatory processes, inhibit carcinogenesis, and modify immune resistance. Detoxification with probiotics is environment-friendly and, unlike physical and chemical methods, does not adversely affect the nutritional value and quality of food. In addition, probiotics in food are associated with well-known human health benefits; therefore, as a functional food, they have gained common consumer acceptance. The large-scale application of biodetoxification methods in both agriculture and the food industry is a challenge for the future. Based on contemporary research, this review provides the mechanism of probiotic biodetoxification, possible applications of various probiotics, and future trends. Full article

Waste tire textile fiber (WTTF), a secondary product from the processing of end-of-life tires, is predominantly disposed of through incineration or landfilling—both of which present significant environmental hazards. The incineration process emits large quantities of greenhouse gases (GHGs) as well as harmful substances such as dioxins and heavy metals, exacerbating air pollution and contributing to climate change. Conversely, landfilling WTTF results in long-term environmental degradation, as the synthetic fibers are non-biodegradable and can leach pollutants into the surrounding soil and water systems. These detrimental impacts emphasize the pressing need for environmentally sustainable disposal and reuse strategies. We found that 80% of WTTF was used for the production of thermal insulation mats. The other part, i.e., 20% of the raw material, used for the twining, stabilization, and improvement of the properties of the mats, consisted of recycled polyester fiber (RPES), bicomponent polyester fiber (BiPES), and hollow polyester fiber (HPES). The research shows that 80% of WTTF produces a stable filament for sustainable thermal insulating mat formation. The studies on sustainable thermal insulating mats show that the thermal conductivity of the product varies from 0.0412 W/(m∙K) to 0.0338 W/(m∙K). The tensile strength measured parallel to the direction of formation ranges from 5.60 kPa to 13.8 kPa, and, perpendicular to the direction of formation, it ranges from 7.0 kPa to 23 kPa. In addition, the fibers, as well as the finished product, were characterized by low water absorption values, which, depending on the composition, ranged from 1.5% to 4.3%. This research is practically significant because it demonstrates that WTTF can be used to produce insulating materials using non-woven technology. The obtained thermal conductivity values are comparable to those of conventional insulating materials, and the measured mechanical properties meet the requirements for insulating mats. Full article

The cement industry contributes approximately 7% of global anthropogenic CO₂ emissions, primarily through energy-intensive clinker production. This study evaluates the thermal behavior and gas emissions of seven waste materials (sawdust, pecan nutshell, wind blade waste, industrial hose waste, tire-derived fuel, plastic waste, and automotive shredder residue) as alternative fuels for cement manufacturing, motivated by the limited information available regarding their performance and environmental impact, with bituminous coal used as a reference. Thermogravimetric analysis and differential scanning calorimetry (TGA-DSC) were used to quantify mass loss and energy changes, while TGA coupled with mass spectrometry (TGA-MS) was used to identify volatile compounds released during thermal degradation. Both TGA-DSC and TGA-MS were conducted under oxidative conditions. The analysis revealed that these waste materials can generate up to 70% of coal’s energy, with combustion primarily occurring between 200 °C and 600 °C. The thermal profiles demonstrated that these materials can effectively replace fossil fuels without releasing harmful toxic gases like HCl, dioxins, or furans. Combustion predominantly emitted CO₂ and H₂O, with only trace volatile organic compounds such as C₃H₃ and COOH. The findings highlight the potential of alternative fuels to provide substantial energy for cement production while addressing waste management challenges and reducing the industry’s environmental impact through innovative resource valorization. Full article

Exposure to endocrine-disrupting chemicals (EDCs) has been linked to several pathologies in human health, especially those involving the immune system. The vast majority of studies have focused on cells and functions of the adaptive immune system with little investigation of the impact of EDCs on innate immunity. While EDC exposure remains a threat throughout the lifetime of an individual, the most detrimental effects on human health occur during critical stages of development, such as in utero. Fetal development is not only associated with growth and tissue remodeling but also with the establishment of key processes, including those of the immune system. Unfortunately, due to fetal plasticity, developmental exposure to certain EDCs, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), can affect mammalian health well into adulthood by altering fetal programming. Herein, we hypothesize that in utero exposure to TCDD induces developmental reprogramming of the innate immune system that subsequently impacts the adult response to infection. To interrogate our hypothesis, we challenged adult mice with and without a history of in utero TCDD exposure with 1 × 10⁸ CFU Pseudomonas aeruginosa via intraperitoneal injection. Results revealed a significant decrease in the number of innate leukocytes at the site of infection six hours after inoculation in toxicant-exposed mice compared to unexposed mice. The reduction in the number of phagocytes correlated with a reduction in bacterial clearance in toxicant-exposed mice. We also noted a decreased ability of peritoneal immune cells from toxicant-exposed mice to produce chemokines necessary for immune cell recruitment. Taken together, our results indicate that in utero EDC exposure impairs the innate immune response to a bacterial infection in adult offspring, particularly in males. Full article

The removal of polychlorinated dibenzo-p-dioxins (PCDDs) via advanced oxidation processes (AOPs) poses a significant challenge due to their high toxicity and chemical stability. In this study, a series of well-dispersed cobalt nanoparticles supported on carbon nitrides (xCoCNs) was synthesized to activate peroxymonosulfate (PMS) for 2,8-dichlorodibenzo-p-dioxin (2,8-DCDD) degradation under visible light. The catalysts prepared were characterized using SEM, XPS, photoluminescence (PL), and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). Among them, 2CoCN with an optimal Co content exhibited the highest photocatalytic efficiency, achieving 90.5% degradation of 2,8-DCDD within 160 min under visible light/persulfate oxidation (Vis+PMS+2CoCN system). Compared with other catalysts, 2CoCN exhibited superior optical performance and a narrower bandgap, enabling efficient excitation under visible light (Vis). Notably, all xCoCNs demonstrated pH adaptability, achieving complete degradation of 2,8-DCDD under neutral conditions (pH = 7) without additional acid/alkali adjustment. Through rigorous free radical capture experiments, it was demonstrated that SO₄^•−, ^•OH and ¹O₂ were the primary reactive oxygen species (ROS) in the Vis+PMS+2CoCN system. The catalyst exhibited excellent reusability, with stable activity retained over five cycles. Based on these findings, degradation pathways and mechanisms of 2,8-DCDD in the 2CoCN+Vis+PMS system were proposed. This study presents an effective approach for PCDD abatement in wastewater treatment applications. Full article

The safe and resource-efficient utilization of waste incineration fly ash (WIFA) has emerged as a pressing challenge in solid waste management. In this work, WIFA was used to prepare a bifunctional catalyst (Metals_x/4@WIFA-S) for the production of levulinic acid (LA) from glucose. The yield of LA was 42.3% with water as the solvent. Moreover, adding 20% γ-valerolactone (GVL) to the system increased the yield to 50.7%. Reaction kinetics and molecular dynamics simulations were applied to elucidate the mechanism by which the solvent system enhanced the catalytic performance of the Metals_x/4@WIFA-S catalyst. Additionally, the environmental risks of WIFA in the preparation of catalysts were evaluated. The dioxin decomposition rate in the catalyst was calculated to be 99.87%, effectively achieving the detoxification of the catalyst. The concentration of heavy metals in the hydrolysate complied with emission standards, thereby reducing environmental risk. This study confirms that waste incineration fly ash-based bifunctional catalysts are effective and safe catalysts with great potential for application in biomass catalysis. Full article

One pair of novel enantiomers, gigantdioxin A (+)-1 and B (−)-1, with a skeleton of benzo[d][1,3]dioxin; a new acetophenone gigantone A (3); a known 3-chlorogentisyl alcohol (2), which is the bioprecursor of 1; acetophenone (4); and chromone derivative (5) were obtained from the sponge-associated fungus Aspergillus giganteus MA46-5. Their structures were established by extensive and in-depth spectral analysis, such as UV, 1D and 2D NMR, and HRESIMS. The absolute configurations of (±)-1 were deduced by ORD, chiral separation, and experimental and computational ECD. Meanwhile, we proposed a possible biosynthetic pathway of (±)-1. Fortunately, the pathway was proved by biomimetic synthesis through 2, as a bioprecursor, reacted with n-butyraldehyde. Myocardial protection assays showed that 3 and 4 possessed stronger protective effects than a positive control against myocardial cell H9c2 ischemia–reperfusion injury in low concentrations, and the effect of (−)-1 was almost equal to that of the positive control. Further, we explored the possible mechanism of myocardial protection through network pharmacology. Adenosine A2a receptor (ADORA2A) and serum albumin (ALB) represent potential targets for myocardial protection associated with (−)-1 and 4, respectively. Based on the network pharmacology, we docked the predicted proteins with bioactive compounds using Autodock Vina. Full article

The aviation industry significantly contributes to global greenhouse gas (GHG) emissions, accounting for approximately 2–3% of total annual CO₂ emissions, with high-altitude operations amplifying radiative forcing effects. This study quantitatively examines aviation’s contributions to global pollution compared to other transportation sectors, such as road and maritime, highlighting the substantial challenges in mitigating its environmental footprint. We focus on emissions of organic compounds, including polycyclic aromatic compounds and dioxins, and analyze key pollutants such as CO₂, NO_X, and ultrafine particles alongside the sector’s indirect effects. Our estimation indicates that dioxin emissions from commercial flights are negligible, at only 0.76 g annually; however, the sector’s broader impact on climate and air quality is significant. The analysis also evaluates current mitigation strategies, including the adoption of sustainable aviation fuels (SAFs), international initiatives like CORSIA, and advancements in aircraft technologies and operational efficiency. Despite these efforts, the projected growth in air traffic, estimated to increase annually by 5% over the next decade, underscores the urgent need for accelerated innovation and robust policy frameworks to achieve sustainable aviation. These findings emphasize the necessity of addressing aviation’s unique environmental challenges through international cooperation, technological advancements, and targeted climate actions. Full article

Human chemical carcinogenesis is a multistage process where chemicals or their metabolites cause irreversible changes in normal cell physiology, eventually leading to uncontrolled proliferation, transforming a normal cell into a cancerous one. Signal transducer and activator of transcription 3 (STAT3) is a cytoplasmic transcription factor that regulates cell proliferation, differentiation, apoptosis, angiogenesis, inflammation, and immune responses. Its aberrant activation triggers tumor progression by promoting the expression of oncogenic genes; thus, STAT3 is classified as an oncoprotein. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that responds to a wide variety of chemicals, including carcinogens like dioxins, inducing genes associated with detoxification, proliferation, and immune regulation. Recent reports show that AhR plays a critical role in cancer development and maintenance. AhR may interact with signaling pathways, like the STAT3 pathway, which mediates the carcinogenic effects of several pollutants. Various chemical agents, such as industrial waste and hydrocarbon compounds, can alter the expression or signaling activity of AhR and STAT3 pathways, leading to different types of cancers. Understanding the complex STAT3-AhR network in the regulation of chemical carcinogenesis could open new avenues for cancer prevention or treatment, particularly in personalized medicine, aiming to improve life expectancy and achieving a complete cure. Full article

Particulate matter coexists with persistent organic pollutants (POPs) in the atmosphere, which can enter the human body by accompanying inhalable particles in the respiratory tract. Photochemical conversion further alters the chemical composition of the precursor particles and secondary products. This study investigated the effects of nanoscale iron–chlorobenzene mixtures and their photochemical conversion products on early lung development in rat pups. Using network toxicology and animal experiments, we constructed a compound toxicity–target network and developed air exposure models. This study revealed that both pollutants, before and after photochemical conversion, bound to the aryl hydrocarbon receptor (AhR), increased oxidative stress, altered lung tissue morphology, and reduce inflammatory factor expression. Rat pups were highly sensitive to pollutants during critical stages of lung development. However, no significant differences in oxidative stress or inflammation were observed between the pollutants, likely because of immature lung tissues. Once tissue damage reached a threshold, the response to increasing pollutant concentrations diminished. This study provides insights into atmospheric pollutant toxicity and scientific evidence for the risk assessment of dioxin-like nanoscale mixtures. Full article

Fly ash produced by Municipal Solid Waste Incineration (MSWI) contains significant quantities of dioxins, posing a major challenge for safe disposal. Compared to other high-temperature disposal methods, low-temperature pyrolysis (<500 °C) can efficiently degrade dioxins in fly ash at relatively low temperatures. To better understand the effects of water-washing and catalysts on dioxin decomposition during low-temperature pyrolysis, this study investigates the impact of water-washing and three different catalysts (V₂O₅-WO₃/TiO₂, Fe/C, and CaO) on the decomposition of dioxins in washed fly ash (WFA). The results indicate that, despite the fact that water-washing pretreatment causes dioxin enrichment in WFA, the toxic equivalent quantity (TEQ) of dioxins within WFA remains lower at the identical pyrolysis temperature when contrasted with that in raw fly ash (RFA). Low-temperature pyrolysis carried out at 250 °C is capable of degrading 99.3% of the dioxins present in water-washed fly ash, achieving a significantly better performance compared to the raw fly ash, which has a degradation efficiency of merely 80%. Nevertheless, when the temperature is set at 210 °C, the degradation efficiency of the WFA turns out to be relatively low, only reaching 29%. The addition of catalysts remarkably promoted dioxin degradation at 210 °C. Among them, CaO exhibited the most outstanding performance, achieving a degradation efficiency as high as 94.8%. It should be emphasized that the catalyst ratio plays a pivotal role in the degradation process. Specifically, the proportion of CaO should not to be less than 10 wt.%. Full article