Search Results (1,740)

Polycyclic aromatic hydrocarbons (PAHs) are toxic air pollutants mainly released through vehicular emissions and can accumulate on edible plants, posing health risks to humans. This study aimed to isolate and identify endophytic fungi from Allium ampeloprasum and Brassica oleracea var. capitata, which are widely cultivated along roadside areas in the upcountry region of Sri Lanka. Sampling sites included Nuwara Eliya town, Nanu Oya, St. Clair’s, and Meepilimana (control), where above-ground parts of the selected vegetables were collected in six replicates. Fungal isolates were obtained through surface sterilization, and their ability to degrade PAHs (naphthalene, phenanthrene, anthracene, and pyrene) was evaluated using plate assays, spectrophotometric analysis, and high-performance liquid chromatography (HPLC). Phyllosphere PAH concentrations were also measured using HPLC. It revealed significantly higher concentrations of all four PAHs in the phyllosphere of both vegetables at polluted sites, with the highest levels recorded in A. ampeloprasum from Nuwara Eliya town: naphthalene (145.92 ng/g), phenanthrene (97.67 ng/g), anthracene (88.71 ng/g), and pyrene (63.82 ng/g). Most endophytic fungal strains isolated from both vegetables were able to grow on Bacto Bushnell–Haas (BBH) medium supplemented with PAHs, producing colonies exceeding 20 mm in diameter. Spectrophotometric analysis showed that Fusarium liriodendri SP2 (PV400499.1) and Trichoderma atroviride SP1 (PV400486.1) achieved approximately 75% degradation of selected PAHs. Furthermore, HPLC analysis confirmed that these isolates effectively degraded all tested PAHs, with degradation rates of approximately 70%. F. liriodendri was the most efficient degrader, achieving degradation rates of 68.50 ± 2.34% for naphthalene, 65.26 ± 1.21% for phenanthrene, 69.21 ± 1.45% for pyrene, and 66.89 ± 1.98% for anthracene. The PAH degradation byproducts of the selected fungal isolates were non-toxic to Artemia salina, confirming their environmental safety. These results highlight the bioremediation potential of endophytic fungi isolated from A. ampeloprasum and B. oleracea var. capitata in PAH-contaminated environments. Full article

Despite recent advances in polycyclic aromatic hydrocarbon (PAH) research on the Tibetan Plateau (TP), studies investigating the transport potential and accumulation dynamics of these contaminants in the Hengduan Mountains, especially in forest soils which are important sinks for atmospheric PAHs, remain scarce. In the present study, soil and lichen samples (partially located under the forest canopy) were concurrently collected from 62 sampling sites across the Hengduan Mountains to characterize the occurrence, spatial distribution patterns, and underlying controlling factors of PAHs. The total concentrations of the 16 US EPA priority PAHs (∑₁₆PAHs) in soils and lichens ranged from 59.8 to 1163 ng/g and 174 to 3362 ng/g, respectively—values consistently higher than those reported in corresponding matrices from the northern and northwestern TP. Further, concentrations of PAHs in both soil and lichen under the forest canopy are significantly higher than those on the leeward slope without forest. Compositional fractionation of PAHs along the longitudinal and latitudinal gradients of sampling locations indicates significant modulation of PAH distribution by both the Indian monsoon and East Asian monsoon, a pattern further corroborated by air mass backward trajectory analysis. Our results confirm that PAHs can be transported to the southeastern TP slope via long-range atmospheric transport (LRAT). Notably, the combined effects of mountain cold-trapping and forest filtering jointly govern the deposition and spatial distribution of PAHs in this region. Full article

Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (B[a]P), are major risk factors for lung cancer and other diseases, acting through the aryl hydrocarbon receptor (AHR). Alveolar macrophages (AMs) help regulate the lung microenvironment by responding to inhaled toxicants and resident microbiota. Although small extracellular vesicles (sEVs, aka exosomes) released by AMs mediate intercellular communication and immune responses, the influence of lung microbiota on sEV biogenesis and the mechanisms underlying sEV dysregulation during PAH exposure remain unknown. Here, we investigated the interplay between AMs, B[a]P, and lung microbiota, focusing on sEV-associated miRNAs (exo-miRNAs). Murine AMs (MH-S) were exposed to varying B[a]P concentrations in the presence or absence of murine lung microbiota with or without an AHR antagonist. sEVs from each condition were characterized and profiled for miRNA. Distinct miRNA signatures emerged: high-dose B[a]P enriched miRNAs linked to cancer progression, whereas lung microbiota alone or with low-dose B[a]P induced tumor-suppressor miRNAs that limit proliferation and metastasis and promote apoptosis, an effect enhanced by AHR antagonism. Lung microbiota appeared to counteract high-dose B[a]P by modulating tumor-suppressive exo-miRNAs. This study demonstrates that lung microbiota-induced exo-miRNAs critically shape AM-derived sEV-miRNA signaling during PAH exposure. The identified exosomal miRNAs could serve as important exposure biomarkers and therapeutic targets for mitigating B[a]P-induced toxicity and cancer development. Full article

Rivers contaminated with metals and petroleum hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), are still a problem that threatens aquatic ecosystem function. This study describes iron- and sulfate-reducing bacteria, principal drivers of anaerobic organic matter decomposition in aquatic sediments. A polyphasic approach, including culture-dependent, i.e., enumeration by Most Probable Number (MPN), and independent, Sanger and Next Generation Sequencing (NGS) techniques, as well as analytical geochemical analyses, was employed. This study found exceptionally high levels of metals (Al, Mn, Zn, and Pb), PAHs, and sulfates compared to typical freshwater environments, likely due to co-contamination from past petroleum and steel production waste. Microbial communities were dominated by the Thermoproteobacteria. Analysis of the iron-reducing community determined that Geobacter, critical for degrading organic matter using iron, manganese, or arsenic, was the most prevalent genus. Additionally, the presence of diverse groups involved in sulfur cycling, represented by dsrAB genes, high numbers of viable sulfate reducers, a higher abundance of Geobacter, and high levels of sulfate and iron suggests that the cryptic sulfur cycle (CSC) may be operational in this system. In addition, sulfate and iron reducers are known to enhance biodegradation of organic pollutants in the presence of metal oxides and sulfate, and thus warrant further investigation in this co-contaminated system. Full article

Atmospheric particulate matter poses a high risk by carrying potentially toxic components such as polycyclic aromatic hydrocarbons (PAHs). The major sources of these potentially toxic compounds include traffic-related emissions and winter heating, implying the combustion of fossil fuels or biomass. Air pollution, especially chronic exposure, poses the most serious human health hazard in childhood, and several studies emphasise the importance of research on the potential impacts of air pollution in school environments. While indoor air quality studies are already available in Hungary, investigations on outdoor air pollution in school environments are missing. To fill this gap, in a medium-sized Hungarian town, Veszprém, six schools were selected to assess air quality in the outdoor environments where schoolchildren spend their breaks and have physical training. These schools represent different locations and conditions, from high-trafficked sites to suburban environments. Using resuspended dust samples, environmental quality was assessed based on PAH contents of the samples and ecotoxicity tests (Vibrio fischeri bacterial bioassay). Ecotoxicity of the samples moved in a wide range, from highly toxic to non-toxic. PAH measurements indicated considerable contamination in the case of one sample taken from a suburban area. Source apportionment demonstrated that winter heating is also an important pollution source. Full article

This two-week pilot study within the Horizon Europe EDIAQI project evaluated the real-life performance of portable air filtration units in two office environments (a small office and a shared kitchen) under continuous device operation and daily filter replacement. Indoor particle concentrations were monitored continuously using low-cost sensors (LCS) from three providers and supported by gravimetric measurements, while daily activity logs documented occupancy patterns, printing, cooking, and other source events together with purifier ON/OFF status. Particulate matter (PM) mass concentrations showed no systematic improvement during purifier ON periods; instead, temporal variability was dominated by indoor activities and episodic emissions, with occasional short-term peaks around filter replacement suggestive of minor resuspension. Chemical analysis provided a clearer picture: polycyclic aromatic hydrocarbons (PAHs) responded differently across fractions and compositions. Across monitored locations, high-molecular-weight PAHs in the PM₁ fraction decreased during purifier ON periods (approximately 30% lower on average), whereas low-molecular-weight PAHs measured in total suspended particles (TSP) were higher during ON periods, indicating that semi-volatile fractions and activity/ventilation dynamics can outweigh simple filtration effects. Overall, the findings highlight a gap between laboratory-derived filtration performance metrics and outcomes in occupied, mixed-source indoor environments and emphasise the importance of device sizing, placement, airflow mixing, and complementary source control and ventilation strategies when deploying filtration-based IAQ interventions. Full article

The glass industry contributes to long-term soil contamination. This study assesses the impact of over 150 years of industrial activity and over a century of glassmaking processes in the Serbian Glass Factory in Paraćin. Focusing on potentially toxic elements (PTEs) and polycyclic aromatic hydrocarbons (PAHs), ecological and human health risks were evaluated. Sampling was conducted at 34 locations within the factory area, including 33 soil samples (0–30 cm) and one industrial waste (IW) sample. Soil analyses indicate that Zn, Ni, Cu, and Cd exceeded both the maximum permissible concentrations (MPCs) and remediation values (RVs) in many samples, while As and Hg showed fewer exceedances. Based on the Potential Ecological Risk Index (RI), about 33% of soil samples were moderately to highly polluted, and Cd, Pb, As, and Hg were identified as the main contributors. High levels of PAHs and PTEs reflect the cumulative impact of long-term industrial operations, a historical fire, and secondary sources, including traffic-related emissions from nearby highways. These factors resulted in elevated total carcinogenic risk (TCR) for Ni, Cr, and As. This study highlights soil contamination and associated health risks at the glass factory, emphasizing the need for environmental monitoring and management. Full article

Pyrolysis of refuse-derived fuel (RDF) is a promising waste-to-energy route, but its use in higher-value applications remains limited by tar carryover, benzene, toluene, ethylbenzene, and xylenes (BTEX), heteroatom-containing compounds, and pollutant accumulation in recirculated scrubber water. This study evaluated operating windows for RDF pyrolysis coupled with direct wet scrubbing and closed-loop water reuse, with the aim of identifying regimes suitable for different end-use tiers. A Taguchi L27 design of experiments (DOE), i.e., an orthogonal array comprising 27 experimental runs, was applied to evaluate the effects of pyrolysis temperature, residence time, scrubber liquid-to-gas ratio, and scrubber-water temperature, while sequential reuse of the same scrubber-water inventory was evaluated at 5, 10, and 15 cycles. Cleaned-gas pollutants were quantified by compound-resolved gas chromatography–mass spectrometry (GC–MS) after solid-phase adsorption (SPA) sampling, while phenolics and polycyclic aromatic hydrocarbons (PAHs) in scrubber water were determined by extraction followed by GC–MS. Feasibility within each end-use tier was defined as simultaneous satisfaction of tier-specific cleaned-gas thresholds (C_tar, C_BTEX, I_N, and I_S) and the corresponding water-loop hazard limit (I_tox), using literature-informed engineering screening criteria. The results showed that stronger scrubbing reduced gas-phase tar and BTEX burdens, whereas extended water reuse caused systematic accumulation of phenolics and PAHs and increased the composite water-loop hazard index. Boiler-grade operation remained feasible across a broad operating range, with 23 of the 27 tested conditions remaining robust, whereas internal combustion engine combined heat and power (ICE-CHP) feasibility was restricted to a narrow robust regime, and no robust microturbine-grade condition was identified. These findings show that operating windows for RDF pyrolysis must be defined jointly by gas cleanliness and water-loop management constraints. Full article

Wildfire impact on boreal watersheds was assessed across Alberta’s Regional Aquatics Monitoring Program (RAMP) domain by integrating multidecadal river, lake, and sediment physical–chemical data with historical wildfire perimeters, polycyclic aromatic hydrocarbon (PAH) indicators, continuous multiparameter sonde records, and pre-/post-fire hydrologic simulations. Site classification, distinguishing reference, industrial, wildfire, and combined influences, was used to enable spatial and temporal comparisons before, during, and after fires. Our synthesis indicated that wildfire acts as an important disturbance that alters watershed connectivity and transport pathways, resulting in shifts in water quality and quantity in surface waters and longer-term adjustments retained in sediments. The interpretation of chemical signatures, including PAHs, was complicated by overlap between areas with wildfire and industrial activities, highlighting cumulative effects and the importance of spatio–temporal context when assessing and quantifying source contributions for long-term resource sustainability. Hydrologic alteration emerged as the dominant downstream wildfire effect, emphasizing the need for long-term continuous monitoring of fire-responsive indicators, in addition to improved assessment of subsurface pathways in wildfire-prone boreal systems. Full article

Halogenated derivatives of polycyclic aromatic hydrocarbons (PAHs), such as chlorinated PAHs (ClPAHs), are an emerging class of contaminants that are being detected in the environment as well as in wildlife and human populations. Previous studies have shown that chemical substitution of PAHs, including chlorination, may alter the toxicity of parent PAHs; however, whether chlorination affects their endocrine-disrupting potential remains unexplored. In this study, we examined the effects of phenanthrene (Phe), one of the most prevalent PAHs, and its chlorinated congeners, 9-chlorophenanthrene (9ClPhe) and 9,10-dichlorophenanthrene (9,10Cl₂Phe), on hormone production in granulosa cells, key hormone-secreting cells of the ovary. We observed that Phe and its chlorinated congeners differentially altered anti-Müllerian hormone (AMH), estradiol (E2), and progesterone (P4) secretion. Since mitochondria are central to steroidogenesis, we further evaluated mitochondrial function. While Phe increased ATP production, both 9ClPhe and 9,10Cl₂Phe increased ROS, decreased mitochondrial membrane potential, and reduced the expression of markers for mitochondrial dynamics and mitophagy without altering ATP levels. We further tested impacts on cell fate and found that neither Phe nor its chlorinated congeners altered granulosa cell apoptosis. Together, these results suggest that chlorination of Phe leads to dose-dependent, differential effects on hormone production and mitochondrial pathways without inducing cell death in granulosa cells. This study highlights the potential adverse impacts of ClPAH exposure on ovarian follicle development and female fertility by disrupting steroidogenesis and mitochondrial quality control. Full article

Microplastics (MPs) are synthetic polymer particles that are generally less than 5 mm in size and have attracted heightened scrutiny due to their pervasive presence in the environment, along with their toxicological significance. Several research investigations documented its presence in humans as a profound finding in biological tissues and fluids crossing barriers, leading to oxidative and inflammatory pathways alterations associated with blood, placenta, cardiovascular, pulmonary, nephrotic, other systems, and their disorders. Given the ubiquitous utilization of microplastics across diverse sectors, it is imperative to systematically investigate and elucidate their potential toxicological effects on biological systems through rigorous and mechanistically informed research. This review will also provide the synthesis of recent mechanistic data on the toxicity that can be caused by MPs and will determine key gaps that impede efficient human health risk evaluation. A structured literature search was conducted via PubMed, Web of Science, and Scopus databases, mostly from the studies published between 2010 and 2026. The studies of exposure characteristics and biological effects were analyzed in vitro, in vivo, and in human biomonitoring, and the primary focus of the interventions includes oxidative stress, inflammation, apoptosis, hepatotoxicity, and metabolic malfunction. MPs possess various physicochemical properties, such as a low particle size, various shapes, surface area, polymer composition, and the presence of sorbed or intrinsic additives. When MPs are taken up by cells, they can induce oxidative stress via increasing ROS, eventually leading to high lipid peroxidation, mitochondrial malfunction, DNA fragmentation, and eventually cell death. MPs also cause pro-inflammatory cytokine responses, including TNF-α, IL-1β, and IL-6, altering the immune system and cell profile, leading to systemic inflammation. In aquatic and terrestrial organisms, these microplastics have a harmful impact on growth, reproduction, and behavior in a time- and dose-dependent manner. Under conditions of controlled exposure, the organ-specific toxicities that have been reported include hepatic, renal, neurological, reproductive, and cardiovascular systems. Although the fields of mechanistic knowledge are growing, there is still a substantial amount of uncertainty; there is a lack of characterization of the long-term effects of low-dose chronic exposure, the kinetics of bioaccumulation, biodegradation potential, and transgenerational effects. In addition, there are no standardized procedures for the characterization of MPs, nor the reporting of the distribution of size or exposure measurements, which limits the comparability of cross-studies and makes it difficult to assess risks quantitatively. The dynamics of interactions of MPs between co-adsorbed contaminants like heavy metals, polycyclic aromatic hydrocarbons, and endocrine-disrupting chemicals are also yet to be explored. Although all evidence available to date does indicate biologically plausible mechanisms of MP-induced toxicity, integrated research employing standardized analytical protocols, an environmentally relevant exposure model, and human epidemiological data is required to ensure that laboratory results are translated into evidence-based public health and regulatory actions. This review offers an in-depth analysis of the existing molecular understanding of MP-induced toxicity, demonstrates organism-level impacts throughout species, and establishes vital fields for future studies. In order to develop competent guidelines to minimize MP exposure and its adverse health effects, it is crucial to cover these gaps via research that incorporates toxicology and environmental science. Full article

Wood biomass ash (WBA) from thermal power plants is often landfilled despite its potential as a secondary raw material. This study adopts a circular economy perspective to assess the physicochemical properties, valorization potential, and environmental risks of WBA, aiming to support its use in agriculture and environmental management. Comprehensive characterization included pH, cation exchange capacity (CEC), proximate and elemental composition, and selected organic contaminants, including polycyclic aromatic hydrocarbons (PAHs). The WBA exhibited a strongly alkaline pH (10.55), moderate CEC (4.36 cmol kg⁻¹), and high ash content (78.32%), with lower nutrient content than other biomass ashes. Major elements included Ca (6.84%), K (2.90%), and Si (3.19%), while nitrogen was absent. Potentially toxic elements (PTEs) such as As, Cd, and Ni were below detection limits; Cr, Cu, Pb, and Zn remained within most regulatory thresholds, although Zn exceeded some limits. ΣPAHs were low (0.05 mg·kg⁻¹), indicating minimal environmental concern. Despite reduced nutrient richness, the ash demonstrated suitability as a liming agent and supplementary nutrient source, provided that Zn levels are managed and nitrogen is supplemented. These results support the redirection of WBA from disposal to beneficial use, advancing circular economy goals and contributing to more sustainable and resilient agricultural systems. Full article

Polycyclic aromatic hydrocarbons (PAHs)-contaminated soils are often concomitantly polluted with heavy metals, which form combined contamination through cation–π interactions and other mechanisms. However, the mechanism by which bacteria degrade PAHs under combined pollution conditions remains insufficiently studied. In this study, a benzo[a]pyrene (BaP)-degrading bacterial strain, Rhodococcus sp. PDS1, was isolated from the co-contaminated soil of an abandoned coking plant in a steel factory. This strain can not only detoxify arsenic via reductive transformation, but also mediate extracellular arsenic oxidation and efficiently degrade BaP, a high-molecular-weight (HMW) polycyclic aromatic hydrocarbon with low bioavailability and high toxicity. Response surface methodology (RSM) experiments were conducted to optimize the degrading conditions of strain PDS1, considering four factors: pH, temperature, BaP concentration, and trivalent arsenic As(III) concentration. The results showed that the BaP removal by PDS1 would reach 93.59% under the RSM-obtained optimal conditions: pH 7.7, BaP concentration 8.96 mg/L, As(III) concentration 0.82 mM, and culture temperature 36.0 °C. The transcriptome of the strain under the combined stress of arsenic and BaP was further analyzed. The results indicated that the introduction of arsenic induced the upregulated expression of different genes in the arsenic detoxification ars operon and the pcaH/G gene (encoding protocatechuate 3,4-dioxygenase, a key enzyme in BaP degradation) to varying degrees. These findings clarify the mechanism of the degradation of HMW-PAHs such as BaP by strain PDS1 under PAHs–arsenic combined pollution, lay a solid theoretical foundation for subsequent practical applications, and demonstrate the broad prospects of strain PDS1 in the remediation of actual complex contaminated soils. 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

Unpolluted water, both freshwater and saltwater, is essential for achieving several United Nations Sustainable Development Goals, particularly SDGs 6, 3, 2, 14, and 15. This study maps emerging water-quality monitoring technologies at intermediate technological readiness levels (TRLs 4–5) and their potential patent markets (TRL 9). A total of 40,469 patent families were retrieved from the Espacenet worldwide database using IPC G01N33/18 and used to analyze sensing parameters. A subset of 2146 water-pollution-related patents was analyzed in detail. The analysis covered sensing parameters, temporal trends, compound annual growth rates (CAGR), legal status, geographic distribution of patent origins and markets, and the technological landscape, including application domains and niche clusters. The results show pronounced exponential growth in patent filings since 2014 and a high share of active documents, indicating sustained global investment. Innovation leadership is concentrated in China, South Korea, India, the United States, and Japan, with export-oriented patents largely held by transnational corporations, while African participation remains limited. Technological trends prioritize multiparameter environmental and biological sensing, addressing pH, temperature, turbidity, dissolved oxygen, nutrients, heavy metals, polycyclic aromatic hydrocarbons (PAHs), and oxidation–reduction potential. Emerging solutions integrate autonomous platforms, remote sensing, Internet-of-Things architectures, and machine-learning-based analytics. Persistent bottlenecks include sensor robustness in harsh aquatic environments and the reliable discrimination between background variability and early pollution signals. Strengthening low-cost and scalable deployment remains essential to ensure water quality, support environmental sustainability, and minimize risks. Full article