Search Results (457)

In the context of increasing concern over long-term environmental impacts of closed landfill sites, this study investigates the composition of groundwater and leachate at a municipal waste landfill in southwestern Poland, two decades after its closure. The research, conducted in 2023, aimed to assess groundwater quality using 11 physico-chemical and 13 microplastic indicators. Groundwater and leachate samples were collected seasonally to assess of groundwater quality around landfill, including presence of heavy metals (Cd, Cr⁶⁺, Cu, Pb), PAHs and TOC, and microplastics. The results revealed persistent environmental degradation, with elevated concentrations of total organic carbon (24.8 mg/L) and cadmium (0.0211 mg/L), particularly in the second half of the year. Additionally, PET microplastics were detected in correlation with increased precipitation and leachate generation. These findings indicate that pollutants continue to migrate from the waste deposit into the surrounding groundwater, with seasonal patterns amplifying their presence. The study confirms that even decades after closure, municipal landfills can remain significant sources of both chemical and microplastic contamination, underlining the need for long-term monitoring and remediation strategies to protect groundwater resources. Full article

Unionid mussel populations in a section of the Clinch River in Virginia, USA, has declined substantially, but the causes of the decline remain unknown. To investigate this zone of decline (ZOD), we deployed juvenile freshwater mussels (Villosa iris in 2012 and Lampsilis fasciola in 2013) in both cages and silos at sites within the Clinch River System. We analyzed mussel tissues for trace element and organic contaminant concentrations, shells for trace elements, and environmental media (total water, dissolved water, particulate sediment, and bedload sediment) for both inorganic and organic contaminants. We found a few differences between mussels deployed in cages and those deployed in silos: survival was slightly lower in cages due to periodic sedimentation. Our results identified the ZOD based on the accumulation of trace elements (notably As, Cu, Fe, Mn, Ni, and Sr), polycyclic aromatic hydrocarbons (PAHs), and δ¹⁵N enrichment, with especially high concentrations found in the human-impacted tributaries, Dumps Creek and Guest River. Some correlations were found between environmental media and both mussel tissues and shells. In particular, PAHs and Mn had several significant relationships between bioaccumulated concentrations and environmental concentrations. Finally, Co, Cu, Fe, and V in soft tissues negatively correlated with mussel growth, whereas bioaccumulated PAH concentrations correlated negatively with resident mussel densities. Full article

Soil contamination with petroleum hydrocarbons is a serious environmental issue, necessitating the development of effective and environmentally friendly remediation methods that align with the principles of sustainable development. This study investigated the impact of selected biosurfactants on the efficiency of the biodegradation of total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs) in contaminated soil. Six biosurfactants—poly-γ-glutamic acid (γ-PGA), rhamnolipid, surfactin, a mixture of γ-PGA, rhamnolipids, and surfactin (PSR), as well as two commercial formulations (JBR 425 and JBR 320)—were evaluated in combination with a bacterial consortium. Biodegradation experiments were conducted under laboratory conditions for a 90-day period. The effectiveness of the tested biosurfactants was assessed using respirometric analysis, the chromatographic determination of the residual hydrocarbon content, and toxicity assays. The results showed that the application of a bacterial consortium enriched with a mixture of biosurfactants PSR (a biosurfactant concentration in the inoculating mixture: 5 g/dm³) was the most effective approach, resulting in an oxygen uptake of 5164.8 mgO₂/dm³ after 90 days, with TPH and PAH degradation rates of 77.3% and 70.32%, respectively. Phytotoxicity values decreased significantly, with TU values ranging from 6.32 to 4.62 (growth inhibition) and 3.77 to 4.13 (germination). Toxicity also decreased in the ostracodtoxkit test (TU = 4.35) and the Microtox SPT test (TU = 4.91). Among the tested biosurfactants, surfactin showed the least improvement in its bioremediation efficiency. Under the same concentration as in the PSR mixture, the oxygen uptake was 3446.7 mgO₂/dm³, with TPH and PAH degradation rates of 60.64% and 52.64%, respectively. In the system inoculated with the bacterial consortium alone (without biosurfactants), the biodegradation efficiency reached 44.35% for TPH and 36.97% for PAHs. The results demonstrate that biosurfactants can significantly enhance the biodegradation of petroleum hydrocarbons in soil, supporting their potential application in sustainable bioremediation strategies. Full article

In ecotoxicological risk assessment, current methods for measuring the transfer and bioavailability of organic pollutants like polycyclic aromatic hydrocarbons (PAHs) in bioindicators are often destructive and environmentally unfriendly. These limitations are especially problematic when only small amounts of biological material are available. Here, we present a novel, high-throughput method combining laser-induced UV fluorescence spectroscopy (UV-LIF) and solid-phase spectroscopy (SPS) for rapid, in situ quantification of PAHs in land snails—a key bioindicator species. Using dual excitation wavelengths (266 nm and 355 nm), our method reliably detected pyrene and fluoranthene in snails exposed to varying concentrations, demonstrating clear dose-responses and inter-individual differences in bioaccumulation. The analysis time per sample was under four minutes. This approach allows simultaneous measurement of internal contaminant levels and health biomarkers in individual organisms and aligns with green chemistry principles. These findings establish a new, scalable tool for routine assessment of PAH transfer and bioavailability in diverse ecosystems. Full article

This study investigates hazardous emissions from foundry binder systems, comparing organic resins (phenolic urethane, furan, and alkaline-phenolic) and clay-bonded green sand with inorganic alternatives (sodium silicate and geopolymer). The research was conducted at the Fundaciόn Azterlan pilot plant (Spain), involving controlled chamber tests for the production of 60 kg iron alloy castings in 110 kg sand molds. The molds were evaluated under two configurations: homogeneous systems, where both mold and cores were manufactured using the same binder (five trials), and heterogeneous systems, where different binders were used for mold and cores (four trials). Each mold was placed in a metallic box fitted with a lid and an integrated gas extraction duct. The lid remained open during pouring and was closed immediately afterward to enable efficient evacuation of casting gases through the extraction system. Although the box was not completely airtight, it was designed to direct most exhaust gases through the duct. Along the extraction system line, different sampling instruments were strategically located for the precise measurement of contaminants: volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), phenol, multiple forms of particulate matter (including crystalline silica content), and gases produced during pyrolysis. Across the nine trials, inorganic binders demonstrated significant reductions in gas emissions and priority pollutants, achieving decreases of over 90% in BTEX compounds (benzene, toluene, ethylbenzene, and xylene) and over 94% in PAHs compared to organic systems. Gas emissions were also substantially reduced, with CO emissions lowered by over 30%, NO_x by more than 98%, and SO₂ by over 75%. Conducted under the Greencasting LIFE project (LIFE 21 ENV/FI/101074439), this work provides empirical evidence supporting sodium silicate and geopolymer binders as viable, sustainable solutions for minimizing occupational and ecological risks in metal casting processes. Full article

The release of polycyclic aromatic hydrocarbons (PAHs) into the environment has become a serious concern with rapidly increasing human activities. PAHs are one of the hazardous pollutants generated primarily from the incomplete combustion of fossil fuels, industrial emissions, and the expenditure of vehicles. These toxic compounds are very dangerous to ecosystems and human health due to being persistent, bioaccumulative, and carcinogenic. Composting is considered a form of bioremediation for eliminating PAHs in contaminated soils. The method utilizes microbial communities to break down organic pollutants and is low-cost and environmentally friendly. The efficiency factor depends on many aspects, including soil pH, oxygen, temperature provision, and the diversity of microbes, among others. Thermophilic conditions help in the decomposition of both low- and high-molecular-weight PAHs. This paper focuses on the effectiveness of composting as a bioremediation technology for remediating PAH-contaminated soils and its impact on the environment and human health. Due to its safety and high efficiency, composting should be improved and prioritized for its widespread application as a principal remediation technology for PAH pollution at the earliest opportunity. Full article

Persistent Organic Pollutants (POPs) are contaminants that pose potential harm to environments and human consumers. Wild mussels (Mytilus galloprovincialis, Choromytilus meridionalis, and Perna perna) were collected from the coastline of the Western Cape Province of South Africa and analysed for polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polyaromatic hydrocarbon (PAHs) via gas chromatography tandem mass spectrometry. The results showed eleven PAHs at concentrations ranging from NF to 50.3 ng g⁻¹ d.w., five PCBs at concentrations between 4.1 and 18.6 ng g⁻¹ d.w., and two OCPs, namely β-hexachlorocyclohexane (NF–7.9 ng g⁻¹ d.w.) and chlordane (7.2–14.5 µg g⁻¹ d.w.). A Human Health Risk Assessment (HHRA) determined PAH concentrations to pose little health risk to adults and children consuming < 1000 g and 500 g per month (g m⁻¹) wild mussel meat, respectively. The HHRA of PCBs found adults and children would experience negative health effects at a consumption rate of 250 g m⁻¹. HHRAs determined chlordane concentrations to pose unacceptable health risks for adults and children at all consumption rates (similar results for lindane). To avoid unnecessary POP-related health risks over a lifetime, it is recommended that adults consume < 250 g m⁻¹ of wild mussels from the Western Cape Province, and children should avoid consuming mussels. This research demonstrates the legacy of POP contamination along the coastline of the Western Cape Province; more monitoring of these contaminants is imperative to protect marine ecosystems and food chains. Full article

Thermal-processed foods like baked, smoked, and fried products are popular for their unique aroma, taste, and color. However, thermal processing can generate various contaminants via Maillard reaction, lipid oxidation, and thermal degradation, negatively impacting human health. This review summarizes the formation pathways, influencing factors, and tracing approaches of potential hazards in thermally processed foods, such as polycyclic aromatic hydrocarbons (PAHs), heterocyclic aromatic amines (HAAs), furan, acrylamide (AA), trans fatty acids (TFAs), advanced glycation end-products (AGEs), sterol oxide. The formation pathways are explored through understanding high free radical activity and multiple active intermediates. Control patterns are uncovered by adjusting processing conditions and food composition and adding antioxidants, aiming to inhibit hazards and enhance the safety of thermal-processed foods. Full article

To date, few studies have been carried out on the influence of the mixing effects of soils and remediation agents on the remediation effects of benzo[a]pyrene (B[a]P) in contaminated soils. In this study, the mixing effects of soils and remediation agents and the degradation effects of B[a]P under different stirring conditions were investigated by combining stirring tests with discrete element method (DEM) simulation. The results from the stirring tests indicated that the mixing effects of two-stage (C_Drill) drill bits were better than first-stage one-line (A_Drill) and first-stage cruciform (B_Drill) drill bits. The mixing quality of C_Drill at the drilling/raising rates of 2, 2.5, 3, 4, and 7.5 cm/min were 42.13%, 43.20%, 43.98%, and 43.30%, respectively. In terms of the results from the B[a]P oxidation remediation tests, the contaminated soils mixed with C_Dril have better remediation effects for B[a]p than those mixed with A_Dril and B_Dril, since B[a]p in contaminated soils stirred and mixed using C_Drill could not be detected after oxidative degradation. The present study results have proved that the mixing effects of soils and remediation agents could significantly affect the remediation effects of contaminated soils with polycyclic aromatic hydrocarbons (PAHs). Full article

Tyre wear particles (TWPs), generated from tyre-road abrasion, are a pervasive and under-regulated environmental pollutant, accounting for a significant share of global microplastic contamination. Recent estimates indicate that 1.3 million metric tons of TWPs are released annually in Europe, dispersing via atmospheric transport, stormwater runoff, and sedimentation to contaminate air, water, and soil. TWPs are composed of synthetic rubber polymers, reinforcing fillers, and chemical additives, including heavy metals such as zinc (Zn) and copper (Cu) and organic compounds like polycyclic aromatic hydrocarbons (PAHs) and N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD). These constituents confer persistence and bioaccumulative potential. While TWP toxicity in aquatic systems is well-documented, its ecological impacts on terrestrial environments, particularly in agricultural soils, remain less understood despite global soil loading rates exceeding 6.1 million metric tons annually. This review synthesizes global research on TWP sources, environmental fate, and ecotoxicological effects, with a focus on soil–plant systems. TWPs have been shown to alter key soil properties, including a 25% reduction in porosity and a 20–35% decrease in organic matter decomposition, disrupt microbial communities (with a 40–60% reduction in nitrogen-fixing bacteria), and induce phytotoxicity through both physical blockage of roots and Zn-induced oxidative stress. Human exposure occurs through inhalation (estimated at 3200 particles per day in urban areas), ingestion, and dermal contact, with epidemiological evidence linking TWPs to increased risks of respiratory, cardiovascular, and developmental disorders. Emerging remediation strategies are critically evaluated across three tiers: (1) source reduction using advanced tyre materials (up to 40% wear reduction in laboratory tests); (2) environmental interception through bioengineered filtration systems (60–80% capture efficiency in pilot trials); and (3) contaminant degradation via novel bioremediation techniques (up to 85% removal in recent studies). Key research gaps remain, including the need for long-term field studies, standardized mitigation protocols, and integrated risk assessments. This review emphasizes the importance of interdisciplinary collaboration in addressing TWP pollution and offers guidance on sustainable solutions to protect ecosystems and public health through science-driven policy recommendations. Full article

Rhamnolipids and earthworm casts, as efficient and environmentally friendly biostimulants, influence the biodegradation of organic pollutants. However, it remains unclear how rhamnolipids and earthworm casts affect the anaerobic biodegradation of polycyclic aromatic hydrocarbons (PAHs). This work aimed to investigate the efficacy and mechanism of biostimulants on the anaerobic biodegradation of PAHs through PAH degradation, functional gene abundance, and bacterial community structure. The results revealed that both stimulants promoted the anaerobic degradation of typical PAHs, such as phenanthrene, pyrene, and benzo(a)pyrene. Rhamnolipids and earthworm casts promoted the degradation of phenanthrene and pyrene more significantly, with the degradation rate increasing by 13.75% and 16.92%, respectively, and the degradation rate of benzo(a)pyrene increased by 10.26% and 11.7%, respectively. The addition of rhamnolipids and earthworm casts significantly stimulated the abundance of functional genes (UbiD, UbiE) in bacterial communities, and this study indicated a strong association between the abundance of functional genes and PAH degradation efficiency. Furthermore, biostimulants altered the microbial community structure and affected microbial diversity and function. Earthworm casts significantly promoted the Azospirillum (0.02–20.17%) and Acinetobacter (0.01–15.70%) genera, which played an important role in the degradation process of PAHs. Therefore, these findings suggested that the enhancement of anaerobic biodegradation of PAHs by rhamnolipids and earthworm casts is probably due to an increase in abundance of both PAH-degraders and their degrading genes (UbiD, UbiE). This study could provide valuable insights for advancing the sustainable remediation of PAH-contaminated soils. Full article

Snow cover constitutes a medium that can be used as a way of assessing air pollution. The chemical composition of snow layers from the same snowfall event reflects the composition of atmospheric aerosols and dry precipitates, depending on the properties of the adsorbing surface and prevailing weather conditions. Analyzing snow samples provides reliable insights into anthropogenic pollution accumulated in soil and groundwater of different land use type areas, as well as allows the evaluation of the degree and sources of environmental pollution. The aim of the research was to determine the distribution of polycyclic aromatic hydrocarbons in various sites of Zawoja village and identify their possible sources and factors influencing their differentiation. A total of 15 surface snow samples of the same thickness and snowfall origin were collected from different locations in the village in the winter of 2024. The samples were pre-concentrated by solid phase extraction and analyzed by gas chromatography—tandem mass spectrometry. The sampling set was invented, and the extraction procedure and analysis parameters were optimized. A spatial distribution map of PAHs was created. The contamination of ∑16PAHs varied from 710 to 2310 ng/L in melted snow with the highest concentrations detected in Zawoja Markowa by the border of the Babia Góra National Park, which is interpreted mainly as a result of the topographical setting. Medium molecular weight PAHs were the dominant fraction, which, combined with specific PAH ratios, indicate the combustion of biomass and coal as the main source of contamination. Full article

Stormwater runoff from areas with specific industrial, agricultural or logistic land use comprises a significant source of water pollution, yet research on its specific composition remains limited compared to urban stormwater pollution. This review synthesizes findings from different studies to analyze sampling methods, types of pollution parameters and their associated concentration ranges across various non-urban land use types, including industrial and commercial zones, transportation infrastructure (ports, airports, highways, railways) and agricultural areas. Studies differed in sample strategy, investigated phase (water, sediment) and analyzed chemical parameters. The latter can be grouped into sum parameters (e.g., total suspended solids (TSS), chemical oxygen demand (COD)), metals (e.g., nickel, copper, zinc, lead), nutrients (e.g., nitrogen, phosphorus), organic micropollutants (e.g., polycyclic aromatic hydrocarbons (PAH), perfluoroalkyl acids (PFAA)) and microbial contaminants. Results indicate that pollutant loads vary widely depending on land use, with industrial and railway areas showing the highest metal contamination, while agricultural and livestock farming areas exhibit elevated nutrient and microbial concentrations. The heterogeneity of the sampling, analysis and subsequent data processing hindered the statistical condensation of data from different studies. The findings underscore the need for standardized monitoring methods and tailored stormwater treatment strategies to mitigate pollution impact effectively. Full article

Polycyclic aromatic hydrocarbons (PAHs), prevalent aquatic contaminants, arise from burning fossil fuels, a major source of greenhouse gases driving global warming. PAHs and warmer temperatures individually exert diverse negative effects on aquatic organisms. However, the effects of PAH exposure and/or rising temperature remain largely unknown. Liver in vitro models, like the rainbow trout (Oncorhynchus mykiss) RTL-W1 liver cell line, have been employed to unravel PAH-exposure effects, primarily on cell viability and enzymatic activity. Here, monolayer-cultured (2D) RTL-W1 cells were used to assess the co-exposure effects of temperature (18 and 21 °C) and two PAHs, benzo[a]pyrene (B[a]P) and benzo[k]fluoranthene (B[k]F), at 10 and 100 nM. After a 72 h exposure, the cell density and viability were evaluated using the trypan blue and LDH assays. The mRNA levels of the detoxification-associated genes aryl hydrocarbon receptor (AhR), cytochrome P450 (CYP)1A, CYP3A27, glutathione S-transferase omega 1 (GSTO1), uridine diphosphate–glucuronosyltransferase (UGT), catalase (CAT), and multidrug resistance-associated protein 2 (MRP2) were measured by RT-qPCR. Temperature influenced cell viability and LDH leakage. Both PAHs reduced the cell density and upregulated the mRNA levels of AhR, CYP1A, CYP3A27, and UGT, while GSTO1 and MRP2 were only augmented after the higher B[k]F concentration. Temperature influenced CAT and UGT expression. There was no interaction between temperature and the PAHs. Overall, the results show that B[k]F has more effects on detoxification targets than B[a]P, whereas a temperature increase mildly affects gene expression. The RTL-W1 in 2D seems useful for unravelling not only the liver effects of PAH but also the impact of temperature stress. Full article

Intensive industrial activities have led to severe polycyclic aromatic hydrocarbon (PAH) contamination of adjacent lands. Remediating such contaminated soil is crucial for maintaining long-term ecological health and sustainable development. This study systematically assessed the performance of a microwave-activated persulfate (MW/PS) oxidation method in remediating pyrene-contaminated soil. Under conditions of 80 °C and a persulfate concentration of 23.8 mg/g, this system achieved 85.3% pyrene degradation within 30 min, significantly outperforming both single microwave and thermal-activated persulfate (TH/PS) systems. Key factors influencing the oxidation efficiency included the temperature, persulfate and pyrene concentrations, moisture, and humic acid content. An electron paramagnetic resonance analysis confirmed the generation of reactive oxygen species, including ^•OH, SO₄^•− and ¹O₂, in the MW/PS system, while O₂^•− was exclusive to the TH/PS system. However, further experiments revealed that ¹O₂ had a negligible impact on pyrene degradation, suggesting that its role may have been overestimated in previous studies. The high MW/PS performance was attributed to the synergistic effects of both thermal and non-thermal (molecular vibration) mechanisms. Based on these findings, the pathways of pyrene degradation were proposed, with intermediate products exhibiting reduced toxicity and bioaccumulation potential. This study provides valuable insights into the application of MW/PS systems in the remediation of PAH-contaminated soils. Full article