Search Results (2,490)

Dioxins are highly persistent organic pollutants that exist in soil. Their hydrophobic and lipophilic characteristics facilitate long-term stability, posing high risks to the ecosystem and human health. They can be released by different sources, such as the incineration of waste materials, industrial activities, the production of pesticides, and natural or accidental events like forest fires. Dioxins accumulate in food chains and persist in the environment because dioxins are less volatile as well as chemically stable and can strongly bind to organic matter. The accumulation and persistence of dioxins in aquatic and terrestrial systems make them a significant threat to the environment, even at very low concentrations. This review explains the key sources of dioxin-contaminated soil, including industrial emissions and atmospheric deposition, and assesses the associated risks. The transport, places of contamination, and overall status of dioxins are also highlighted in this study. The review also examines the mechanisms of dioxin toxicity, focusing on their interference with hormonal functions and gene expression, as mediated through the aryl hydrocarbon receptor (AhR). This AhR activation leads to gene responses and causes immunotoxicity, endocrine disruption, and oxidative stress. Furthermore, various remediation strategies like biological, physical, and chemical remediation are discussed here as effective approaches for reducing ecological and health risks and promoting soil sustainability. Full article

Landscape pattern is closely associated with pollution in rapidly urbanizing watersheds, but most studies still focus on single pollutants or single environmental media. This study developed a watershed-based framework to compare coupled water and air pollution in the Liaohe River Basin, China. A total of 156 hydrologically connected sub-basins were used as common spatial units. Landscape metrics were calculated for 2000, 2010, and 2020. Total nitrogen and total phosphorus loads were simulated using the Soil and Water Assessment Tool, while annual mean PM_2.5 and O₃ concentrations were aggregated from gridded products to the same sub-basin scale. Coupling coordination degree was used to identify relative co-pollution patterns within the aquatic and atmospheric systems. GeoXGBoost with spatial block cross-validation was used to evaluate predictive performance, and GeoSHAP was used to interpret model-based predictor contributions. The aquatic coupled pollution index was predicted more accurately than the atmospheric index, indicating a stronger landscape association with nutrient coupling. Cropland proportion was the most stable predictor of aquatic coupling, whereas forest proportion was the most stable predictor of atmospheric coupling. These results suggest that water-oriented management should focus on cropland structure and ecological buffering, while air-oriented management should emphasize forest continuity and fragmentation control. The framework provides a spatially explicit basis for differentiated watershed management and territorial spatial planning. Full article

This study examined the effects of several selected commercial detergents (cleaning cream, window cleaner liquid, lavender-scented dishwashing liquid, mint-scented dishwashing liquid, and pomegranate–verbena-scented dishwashing liquid) and the surfactant sodium dodecyl sulfate (SDS) on small aquatic invertebrates. The combined effects of these detergents with sodium chloride (NaCl) were also analysed. Acute toxicity tests were conducted on Chaoborus sp. larvae and Chironomus aprilinus Meigen larvae. These tests demonstrated that all tested substances were lethal to both taxa, although the effect on Chaoborus larvae was weaker. Tests involving sodium chloride combined with detergents yielded results similar to those obtained with detergents alone. LT₅₀ and 24 h LC₅₀ values were calculated. Chronic toxicity tests were conducted on meiobenthic assemblages sampled from two water bodies with contrasting ecological status: very good and eutrophic. Bray–Curtis faunal similarity analysis consistently separated control samples from detergent samples as a distinct cluster. The results indicated toxic effects at all tested dilutions and in samples from both water bodies. Among the observed taxa, Rotifera, Nematoda, Cladocera, Copepoda, Ostracoda, Insecta Diptera larvae, Insecta adult, Gastropoda, and Bivalvia, Ostracoda showed the greatest resistance to detergents, while Rotifera, Nematoda, Cladocera, and Copepoda demonstrated the highest sensitivity. A decrease in abundance and biodiversity was observed in all meiobenthic samples relative to the control samples. The results have a dual significance: 1. based on the obtained data, the developed procedures can be used as markers of detergent toxicity, and 2. in an economy based on sustainable development, commercial detergents should be considered as a serious source of surface water pollution affecting the ecological condition of water reservoirs and rivers. Detergents constitute a significant source of pollution and an obstacle to sustainable development in surface water protection. Full article

Freshwater snails, specifically those belonging to the genus Bellamya, are increasingly recognized as important components of sustainable aquaculture and aquatic ecosystem management. This review synthesizes current knowledge on their ecological roles, aquaculture practices, utilization, and associated risks to evaluate their potential as a multifunctional resource. Available evidence shows that Bellamya species function as bioindicators of environmental change and contribute to water purification through grazing, nutrient cycling, and interactions with aquatic plants. In aquaculture, diverse production systems, including rice–snail co-culture and pond-based farming, have been developed, demonstrating high resource-use efficiency and economic value. In addition to their nutritional importance as a protein source, freshwater snails provide opportunities for value-added products in food, biomaterials, and health-related applications. However, challenges remain, including parasite transmission, the bioaccumulation of environmental pollutants, genetic resource degradation, and ecological carrying capacity constraints under intensive farming. Future development depends on advances in breeding, nutrition, and intelligent farming technologies, as well as improved environmental monitoring and regulatory frameworks. Overall, freshwater snail aquaculture represents a promising pathway for integrating food production with ecosystem restoration, but its sustainable expansion requires coordinated efforts in research, management, and industry development. Full article

Pollution of rivers and large water bodies, including reservoirs, by wastewater from various sources is one of the most critical issues in the Donetsk region, requiring continuous monitoring and assessment of surface water quality. The research aims to assess the state of the Kalmius River under anthropogenic pressure, as well as to find correlations between the species composition, photosynthetic activity of phytoplankton, and the degree of water pollution. This study presents the results of biomonitoring of the Kalmius River and its tributaries within Donetsk City, which are under intense anthropogenic pressure. Pollution of the river channel by phenol, anionic surfactants, Ferrum ions, chlorides, and sulfates was identified. Based on the combinatorial pollution index, the water in the Kalmius River and its tributaries can be classified as polluted. The pigment composition of water samples was analyzed, and the species composition of river phytoplankton was determined. Dominant species include Chlorella vulgaris Beij., Dictyosphaerium pulchellum H.C.Wood, Scenedesmus quadricauda Brébisson, and Oscillatoria agardhii M.A.Gomont. Photosynthetic activity of the river’s algal flora was assessed based on chlorophyll fluorescence induction curves of natural phytoplankton. A correlation was established between surface water pollution levels and changes in the photosynthetic apparatus of microalgae cells. A strong negative correlation was found between the content of nitrate nitrogen in the aquatic environment and the photosynthetic activity, pigment composition, and abundance of the main dominant forms of phytoplankton, particularly the microalgae of the genus Cyclotella. The data obtained shows that the Kalmius River’s pollution has a significant impact on phytoplankton biodiversity, leading to the growth of cyanobacteria species. Full article

The escalating threat of antibiotic resistance, driven by the persistence of tetracycline in aquatic ecosystems, necessitates the development of advanced remediation platforms with high structural efficiency. In this study, a bimetallic Ag-Fe co-doped ZIF-8 framework was strategically engineered to optimize pore accessibility and surface chemical affinity. The resulting nanocomposite exhibited an ultra-high BET surface area of 1322.64 m²/g and a pore volume of 0.502 cm³/g, while maintaining the characteristic structural integrity of the parent ZIF-8. Adsorption benchmarks demonstrated a superior maximum capacity of 417.97 mg/g at pH 8 under ambient conditions. The sequestration process was found to be governed by pseudo-second-order kinetics, while the Freundlich and intraparticle diffusion models accurately described a multilayer adsorption mechanism occurring across heterogeneous active sites. Furthermore, the Ag-Fe-ZIF-8 maintained its structural stability and performance over three consecutive cycles. These findings highlight the potential of bimetallic ZIF-8 derivatives as robust, high-surface-area platforms for the sustainable removal of pharmaceutical pollutants from wastewater, with an adsorption capacity as high as 417.97 mg/g after 3 h. Full article

Water toxicity screening requires sensitive tools to rapidly detect environmental pollutants. While complex analytical methods accurately determine known contaminants, fast screening tests utilizing biological processes, such as photosynthesis, are increasingly being developed to evaluate the toxicity of environmental waters. We describe the isolation of the psychrotolerant Coccomyxa sp. LT4 from Scarisoara Ice Cave (Romania), representing the first report of green algae inhabiting this type of environment, and provide a preliminary assessment of its isolated thylakoids as novel biorecognition components for water toxicity screening. Photosynthetic activity and diuron sensitivity were measured amperometrically and compared with thylakoids from the reference cyanobacterium Synechococcus elongatus PCC 7942. The bioreceptor’s response to various pollutants and water salinities was also investigated. The microalgal thylakoids were more sensitive to diuron than the reference thylakoids, generated stable photocurrents across a broad salinity range and, when lyophilized with sucrose, retained their activity for over two years at −20 °C. Consequently, these thylakoids, isolated from a cold-environment microalga, provide a promising basis for developing biosensors for in situ toxicity screening in low-temperature aquatic ecosystems. Full article

Shallow lakes in the Yangtze River Delta are characterized by fragile ecosystems, strong sediment–water interactions, and poor resistance to pollution shocks; they are prone to shift from macrophyte-dominated clear-water states to phytoplankton-dominated turbid states under intensive human disturbance. To improve the efficacy of aquatic ecological restoration, this study takes a typical shallow urban lake—Kuilei Lake in Kunshan—as the research object, and establishes a two-dimensional hydrodynamic and water quality model to simulate the temporal and spatial variations in flow fields, flow circulations, and water quality indicators (TP, NH₃-N, COD_Mn) throughout the year. The results are as follows: (1) The hydrodynamic regime of Kuilei Lake is dominated by wind-driven currents, with seasonal flow circulations regulating pollutant migration and the suitability for submerged macrophyte growth; (2) Intense circulations in summer (July–September) enhance sediment resuspension and endogenous nutrient release, which are unfavorable for submerged plant colonization; (3) April–June is the optimal window for ecological restoration, with a mean flow velocity of 2.0–2.5 cm/s, TP ≤ 0.06 mg/L, NH₃-N ≤ 0.20 mg/L, COD_Mn ≤ 3.0 mg/L, and water temperature of 15–25 °C, providing favorable thresholds for submerged macrophyte recovery. This study reveals the coupled hydrodynamic–water environmental thresholds for shallow lake restoration, and offers a scientific basis for flow field regulation and ecological reconstruction of shallow lakes in the Yangtze River Delta. Full article

Dissolved organic matter (DOM) plays a central role in estuarine carbon cycling and exhibits dynamically coupled interactions with chlorophyll-a (Chl-a). Under increasing nutrient loads, elevated Chl-a concentrations and shifts in DOM composition serve as key indicators of eutrophication in estuarine aquatic ecosystems. Previous studies have mainly focused on the composition and fluorescence properties of DOM in rivers and lakes. Here, 84 water samples were collected from the Ganjiang River Estuary of Lake Poyang during wet, normal, and dry seasons across the mainstream, middle, and south branches. The average Chl-a concentration showed wet season (6.61 μg·L⁻¹) > normal season (4.54 μg·L⁻¹) > dry season (2.01 μg·L⁻¹). By employing EEM-PARAFAC, five fluorescent components were identified, including C1, C2, C3, C4, and C5. Notably, microbial humic-like substances remained consistently high during the wet season. Two-dimensional correlation spectroscopy was further employed to evaluate sequential changes in DOM components, while a moving window was used to identify temporal variation characteristics. Based on Noda’s rules, the DOM response sequence was identified as C3→C2→C1→C4→C5. Kernel PCA showed that the variable cluster represented by PC1, which consisted of organic pollutants and nutrients, co-varied negatively with Chl-a, whereas the PC2 cluster, representing biogenic organic matter, co-varied positively with Chl-a. Moreover, partial least squares path modeling showed that humic-like and tryptophan-like substances were positively correlated with Chl-a, with the path coefficients of 0.47 and 0.19, respectively. These findings revealed the interaction patterns between DOM components and Chl-a at the river-lake confluence zone, thereby enhancing our understanding of the factors influencing the spatio-temporal variations in Chl-a concentration, and further providing a guide for the control of algal blooms. Full article

The increasing presence of microplastics in the aquatic and terrestrial food chains calls for the need to come up with innovative and effective remediation approaches. Such innovations as zinc oxide (ZnO) structures and metal–organic frameworks (MOFs) are examined as the second generation of photocatalysts for degrading microplastics under sunlight. We will focus on the latest advances and discuss the structure of photocatalytic processes, their functioning under various light conditions, and their environmental impacts, especially environmental safety and ecotoxicity. ZnO structures are even better photocatalysts because they form reactive oxygen species (ROS) as good as other metal oxides. However, their possible cytotoxicity and the ability to generate oxidative stress require serious evaluation. MOFs, on the contrary, offer physicochemical properties, environmental safety, ecotoxicity, and environmentally friendly synthesis pathways, making them a worthy substitute. The review underscores the urgency of incorporating environmental safety and ecotoxicity into the design of photocatalysts, thereby unlocking their full potential while avoiding environmental or human health risks. Moving forward in the field of sustainable nanotechnology to remove microplastics will provide the way to come up with green innovations and hence guarantee the effectiveness of combating plastic pollution in long-term stability. Full article

Three locally calibrated Indices of Biotic Integrity (IBIs) based on macroinvertebrates (B-IBI), zooplankton (Z-IBI), and phytoplankton (P-IBI) were developed to characterize relative aquatic ecological condition at impaired sites in Dongjiang Lake, a deep reservoir-type lake in China, during 2021–2023. Using synchronous monitoring data, candidate metrics for the three biotic groups were screened and assembled by integrating taxonomic diversity, community composition, pollution-tolerance attributes, trophic indicators, and functional feeding groups. Metric values were standardized using a linear transformation, and site conditions were classified using a unified five-class grading scheme under the present local calibration framework. A total of 327 taxonomic units (species or morphospecies) were recorded across the three biotic groups, indicating relatively high biodiversity in the study area. Under the present locally calibrated framework, most impaired sites were classified within the moderate-to-good range, with clear interannual variation and spatial heterogeneity. Upstream and downstream sections showed greater fluctuations in IBI classes than the lake area. The macroinvertebrate-based IBI was more sensitive to long-term and cumulative habitat disturbance, whereas the zooplankton- and phytoplankton-based IBIs responded more rapidly to short-term variation in nutrients and water quality. Together, these results indicate that multitaxon IBIs can provide complementary information on relative ecological condition within Dongjiang Lake and may support ecological zoning, pollutant management, and restoration prioritization in similar deep reservoir-type lake systems. Full article

Pharmaceuticals and personal care products (PPCPs) are widely recognized as persistent contaminants in urban aquatic systems, yet their behavior is typically interpreted under steady-state assumptions driven by continuous discharge of treated wastewater. This paradigm overlooks the dominant role of episodic pollution pulses associated with combined sewer overflow (CSO) events. This review advances a new conceptual framework in which PPCP contamination is understood as a manifestation of complex phenomenon, arising from the interaction of intense precipitation, hydraulic exceedance of sewer systems, and mobilization of accumulated contaminants. We critically synthesize current knowledge on the occurrence, transport, transformation, and removal of PPCPs across wastewater effluents and CSO discharges, integrating insights from degradation kinetics, environmental monitoring, and treatment technologies. Comparative analysis reveals strong matrix-dependent variability in PPCP attenuation, with enhanced degradation in estuarine and marine systems driven by complex photochemical and biogeochemical interactions. However, under CSO-driven pulse conditions, these processes become transient and non-linear, challenging conventional assumptions of steady-state degradation and risk assessment. The findings highlight that CSO events can generate short-duration but high-intensity contamination peaks, often exceeding baseline concentrations and potentially amplifying ecological risks and antimicrobial resistance selection. We propose a matrix-reactivity and pulse-driven framework to better capture the dynamic fate of PPCPs under real-world conditions. Future research should prioritize event-based monitoring, real-time sensing, and time-resolved risk assessment models to address the limitations of current approaches. This work redefines PPCP pollution as a dynamic, episodic, extreme-event-driven process, with important implications for urban water management under increasing climatic variability. Full article

Background: Microplastics, derived from plastic degradation and industrial sources, are widely detected in aquatic environments and food systems, posing increasing environmental and ecological risks. Aims: This study aimed to investigate how microplastics affect host physiology and gut microbiota, as well as determine whether microbiota changes actively modulate host responses. Methods: Using A. salina as a model organism, we combined physiological assays, oxidative stress analysis, gut microbiome profiling, and bacterial functional validation under chronic polystyrene microplastics exposure. Results: Polystyrene microplastics accumulated in the gut and significantly impaired growth and survival, accompanied by reduced digestive enzyme activity and immune function, as well as increased oxidative stress, indicating disruption of physiological homeostasis. Microplastic exposure also induced microbial dysbiosis, characterized by decreased diversity and compositional shifts. Functional assays demonstrated that a bacterium enriched under exposure, Pseudomonas knackmussii, partially restored host growth and physiological functions while reducing oxidative stress. Conclusions: These findings demonstrate that gut microbiota are not only altered by microplastic exposure but also actively modulate host responses to environmental stress, providing new insight into microbiota-mediated resilience under pollutant stress. Full article

The pulping and paper-making (P&P) industry is one of the world’s largest manufacturing sectors, yet it is plagued by high water/energy consumption and massive discharge of highly polluted wastewater. The effluents from pulping, bleaching and papermaking processes are characterized by high chemical oxygen demand (COD), intense color, toxic adsorbable organohalides (AOX) and abundant refractory lignin, which pose significant threats to aquatic ecology and human health. Although conventional physical, chemical and biological treatments have been widely applied, they are constrained by insufficient degradation efficiency toward recalcitrant organics, high cost and potential secondary pollution. In recent years, electrocatalytic technologies including electrocatalytic oxidation, electroreduction and their integrated processes, have demonstrated superior efficacy in specific scenarios of P&P wastewater treatment, such as lignin degradation, toxic side-streams treatment, pretreatment for enhancing biodegradability, and polishing steps in integrated treatment systems, which are not universally applicable solutions for P&P wastewater remediation. Meanwhile, biomass fuel cells typified by direct biomass fuel cells (DBFC) and microbial fuel cells (MFC) provide promising pathways for synchronous pollutant removal, energy production and resource recovery. Representative studies have reported COD removal efficiencies of 60–100% for electrochemical and advanced oxidation processes, while integrated electro-Fenton–biological treatment increased the BOD/COD ratio from 0.34 to 0.52 and achieved an overall COD removal of 94%. It should be noted that these advanced electrochemical technologies are still confronted with challenges in industrial scale-up, high energy and electrode material costs, and stable continuous operation. This review systematically elaborates on the physicochemical properties, generation mechanisms and environmental impacts of P&P wastewater, comprehensively summarizes the mainstream treatment technologies including physicochemical, biological, electrochemical and integrated processes, and analyzes their reaction mechanisms, efficiencies and applicable conditions. Particular emphasis is placed on electrocatalytic treatment and bio-electrochemical valorization strategies. This review is anticipated to provide a valuable reference for the efficient and targeted treatment as well as sustainable utilization of P&P wastewater, thereby supporting the green and low-carbon development of the P&P industry. Full article