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Groundwater is the principal water source of drinking and irrigation in the Dawen River Basin of Shandong Province. Thus, its investigations and evaluations are of significant importances. Based on collected groundwater samples, this study employed a combination of the entropy-weighted water quality index(EWQI), Nitrate Pollution Index(NPI) and the human health risk assessment(HHRA) model to evaluate groundwater quality and associated health risks. The combination of EWQI and NPI provides a more refined classification of groundwater quality in the Dawen River Basin. Geostatistical and GIS spatial analysis methods are employed to analyze the spatial characteristics of groundwater quality and its relationship with geomorphology. Results indicate that the region generally enjoys good water quality, with Entropy Water Quality Index (EWQI) values ranging from 20.32 to 302.37, and an average of 70.88. Downstream quality is poorer than upstream, and flat terrains typically exhibit poorer water quality. The major indicators affecting groundwater quality include Na⁺, Cl⁻, SO₄ 2 ⁻, and NO₃⁻. The NPI results show that due to differences in anthropogenic sources, 38.1%, 27.38%, 26.19%, 4.76%, and 3.57% of the groundwater samples are classified into non-polluted, slightly polluted, moderately polluted, significantly polluted, and extremely significantly polluted types, respectively. The HHRA model reveals high potential non-carcinogenic risks for NO₃⁻ and low risks for F⁻ in the study area. The health risks associated with high levels of NO 3 - in the areas surrounding Dongping Lake and Ningyang County are greater than in those other regions and therefore should be a significant concern for public health. Furthermore, this study attempts to combine the EWQI and NPI to categorize groundwater protection and governance statuses into four types: protective, utilizable, preventive, and remedial. This approach addresses the shortcomings in comprehensively identifying water quality types by single evaluation methods and offers valuable insights for distinguishing water quality types under nitrogen pollution conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

As a typical high geological background area in the middle reaches of the Yangtze River tributary basin in China, the Loushao Basin in Hunan is covered with high mineral black shale, with an average element value 4.76-8.97 times higher than the world average rock level. The aim of this study is to analyze the water environment pollution in the middle reaches of the Yangtze River tributary basin under high geological background based on the spatial distribution differences of black shale concentration. PCA source analysis is used to track the source of pollution and highlight the differences in body shape to assess regional health risks. The research results show that Cd in water quality exceeds the background value by 7.5 times. There is a strong homology among Pb, Cd, Cr, As, and Hg elements in water bodies, mainly derived from the natural weathering, migration, and enrichment of rocks. Hg element is a pollution caused by human factors, and water pollution is more severe in areas close to high concentrations, with severe exceedance of Cr element in water quality. The main controlling factor for individual health risk differences is body shape, and men's health is more susceptible to threats., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Bozhi Ren reports financial support was provided by National Natural Science Foundation of China. Bozhi Ren reports financial support was provided by Hunan Provincial Natural Science Foundation. Luyuan Chen reports financial support was provided by Postgraduate Scientific Research Innovation Project., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cortisone is a naturally occurring corticosteroid hormone known for its wide range of anti-inflammatory and immunosuppressive effects, and it is commonly found in various aquatic environments. Previous reports have shown that cortisone can have significant negative impacts on fish; however, its specific effects on fish reproduction have not been thoroughly investigated. In this study, female adult zebrafish were exposed to 0.0 (control), 3.9, 40.2, and 377.9 ng/L of cortisone for 60 days, and multiple endpoints were evaluated. The results showed that as the concentration of cortisone increased, there was an increase in the percentage of perinuclear oocytes and a decrease in the proportion of late-stage oocytes, indicating a stagnation in oocyte development. Additionally, female zebrafish exposed to cortisone exhibited decreased attraction to males and reduced mating intimacy. Furthermore, exposure to cortisone resulted in changes in the development and behavior of zebrafish embryos. At cortisone concentrations of 3.9 and 40.2 ng/L, fewer eggs were laid and the survival rate of fertilized eggs decreased. These observed effects are associated with abnormal transcription levels of genes (Star, Cyp11a1, Cyp17, Cyp19a, Cyp11b, Hsd11β2, Hsd17β3) related to the HPG axis. These findings provided new insights into understanding potential environmental risks associated with corticosteroids., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Considering the significant hazards of organophosphorus compounds (OPs) and the potential crisis of phosphorus (P) resource shortage, there is a great necessity to develop economically feasible, highly effective, and sustainable strategies to remove OPs and recover P resources. In this study, low-cost microscale zero-valent iron (mZVI) was used to activate hydrogen peroxide for the rapid and efficient elimination of Tetrakis(hydroxymethyl)phosphonium sulfate (THPS) from the aquatic environment. Compared to the conventional Fenton reaction and commercial mZVI, mZVI/H 2 O 2 -based Fenton-like reaction exhibited superior removal performance for THPS. The removal mechanism of the mZVI/H 2 O 2 system for THPS was thoroughly elucidated through the identification of reactive oxygen species, characterization analysis, and theoretical calculation. Furthermore, the valuable components of the degradation products were successfully recovered through thermally induced precipitation of the sample followed by high-temperature calcination. The mZVI/H 2 O 2 system has demonstrated significant advantages in removing organic compounds from various types of actual wastewater and improving the biodegradability of the wastewater. This study presented an environmentally friendly and highly efficient strategy to eliminate OPs pollution and recover P resources. It also provided an easy-to-operate method for remediating actual industrial wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Nano-zinc oxide (ZnO NPs), as widely used nanomaterials, are inevitably released into aquatic environments, posing potential threats to aquatic organisms. Mytilus galloprovincialis is a bivalve species sensitive to changes in marine ecological environments, but there has been limited research on its toxicity response to ZnO NPs. Therefore, we selected M. galloprovincialis as the research subject and exposed them to 50 µg/L ZnO NPs for 96 h and 30 days to determine the dissolution of ZnO NPs in seawater and their distribution in M. galloprovincialis. The toxicity of ZnO NPs in M. galloprovincialis was then evaluated through gene expression, tissue pathology, and cellular immune response. The results showed that ZnO NPs could enrich Zn in various tissues of the mussel, in the order of gills > hepatopancreas > adductor muscle > mantle. Seven immune-related genes including four heat shock protein genes (HSPA12A, sHSP24.1, sHSP22, TCTP) and three apoptotic genes (Ras, p63 and Bcl-2) were altered to varying degrees. There was a downward trend in lysosomal membrane stability of M. galloprovincialis after exposure to ZnO NPs for 96 h and 30 days, while ROS and apoptosis rates increased significantly. Furthermore, the seven genes, apoptosis, LMS, and ROS were dependent on exposure time, treatment, and their interaction. Histopathological damage included disorganisation of hepatopancreas epithelial cells, gill filament swelling, and contraction of blood sinuses. These results indicated that ZnO NPs exerted toxicity in M. galloprovincialis, affecting the immune system, resulting in changes in the expression of immune-related genes and ultimately leading to histopathological changes. Our research findings could contribute to systematically understand the impact of ZnO NPs on bivalves in aquatic environments and provide a theoretical basis for marine pollution assessment., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Xiaoli Liu reports financial support was provided by Ludong University. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Based on multiple ligands strategy, a series of multivariate metal organic frameworks (MTV-MOFs) named as PCN-224-DCDPS x were prepared using one-pot solvothermal method to extract and remove sulfonamide antibiotics (SAs). The pore structure and adsorption performance can be further regulated by modulating the doping ratios of medium-tetra(4-carboxylphenyl) porphyrin and 4,4'-dicarboxydiphenyl sulfones. The MTV-MOFs of PCN-224-DCDPS 1.0 possesses very large specific surface area (1625 m 2 /g). Using PCN-224-DCDPS 1.0 as sorbent, a dispersive solid-phase extraction method was developed to extract and preconcentrate SAs from water, eggs, and milk prior to high performance liquid chromatography analysis. The limits of detection of method were determined between 0.17 and 0.27 ng/mL with enrichment factors ranging 214-327. The adsorption can be finished within 30 s, and the recovery rate remains above 80 % after 10 repeated uses. The adsorption capacities of sorbent were determined from 300 to 621 mg/g for sulfadiazine, sulphapyridine, sulfamethoxydiazine, sulfachlorpyridazine, sulfabenzamide, and sulfadimethoxine. The adsorption mechanisms were investigated and can be attributed to π-π interactions, hydrogen bonds, and electrostatic interactions. This work represents a method for preparation of MTV-MOFs and uses as sorbent for extraction and enrichment of trace pollutants from complex samples., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this paper, series of ionic polymers were synthesized by crosslinking alkyl quaternary ammonium salts with 1,4-bis(chloromethyl)benzene. Among them, hyper-crosslinked polymer fabricated with dodecyl dimethyl benzyl ammonium chloride (HCP-DD) as monomer delivered superior adsorption performance for endocrine disrupting chemicals (EDCs). The adsorption mechanism mainly includes π-π stacking, hydrophobic and electrostatic interaction. With HCP-DD as solid phase extraction sorbent, a high performance liquid chromatography-diode array detection method was developed for the detection of four phenolic EDCs in water and fish samples. The detection limits of the method were 0.005-0.02 ng mL -1 for water samples and 3-30 ng g -1 for fish samples. The recoveries of EDCs in water samples and fish samples were 80-119% and 81.3-117% (relative standard deviations <4.4%), respectively. The study not only provides a route for preparation ionic porous polymers, but also highlights the applications of ionic polymers as efficient adsorbent to enrich organic pollutants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Inorganic mercury (IHg) is hazardous to marine organisms especially resulting in neurotoxicity, bivalves are sensitive to pollutants as "ocean sentinel", but data on the neurotoxicity of IHg in bivalves are sparse. So we chosed M. chinensis philippi with typical neural structures in bivalves to investigate the neurotoxicity of IHg, which could be helpful to understand the specificity of neural regulation and the response characteristics of bivalves. After acute exposed to IHg (HgCl 2 ) for 24 h, the metabolites of ganglion tissues in M. chinensis philippi were evaluated using 1 H-nuclear magnetic resonance based metabolomics; Ca 2+ , neurotransmitters (nitric oxide, glutamate, acetylcholine) and related enzymes (calcineurin, nitric oxide synthase and acetylcholinesterase) were measured using biochemical detection. Compared to the control group, the levels of the nitric oxide (81.04 ± 12.84 μmol/g prot) and acetylcholine (30.93 ± 12.57 μg/mg prot) in M. chinensis philippi of IHg-treated were decreased, while glutamate (2.11 ± 0.61 mmol/L) increased significantly; the activity of nitric oxide synthase (679.34 ± 135.33 U/mg prot) was increased, while acetylcholinesterase (1.39 ± 0.44 U/mg prot) decreased significantly, and the activity of calcineurin (0.52 ± 0.02 U/mg prot) had a statistically insignificant increasing tendency. The concentration of Ca 2+ (0.92 ± 0.46 mmol/g prot) in the IHg-treated group was significantly higher than that in the control group. OPLS-DA was performed to reveal the difference in metabolites between the control and IHg-challenged groups, the metabolites of glucose, glutamine, inosine, succinate, glutamate, homarine, and alanine were sensitive to IHg, subsequently metabolic pathways that were affected including glucose metabolism, glutamine metabolism, nucleotide metabolism, Krebs cycle, amino acid metabolism and osmotic regulation. In our study, IHg interfered with metabolites in M. chinensis philippi, thus the corresponding metabolic pathways were changed, which influenced the neurotransmitters subsequently. Furthermore, Ca 2+ overload affected the synthesis or degradation of the neurotransmitters, and then the altered neurotransmitters involved in changes in metabolic pathways again. Overall, we hypothesized that the neurotoxic effects of IHg on bivalve were in close contact with metabolism, neurotransmitters, related enzymes and Ca 2+ , which could be effective neurotoxic biomarkers for marine environmental quality assessment, and also provide effective data for the study of the regulatory mechanism of the nervous system in response to IHg in bivalves., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Microplastics (MPs), an emerging environmental contaminant, have raised growing health apprehension due to their detection in various human biospecimens. Despite extensive research into their prevalence in the environment and the human body, the ramifications of their existence within the enclosed confines of the human eye remain largely unexplored. Herein, we assembled a cohort of 49 patients with four ocular diseases (macular hole, macular epiretinal membrane, retinopathy and rhegmatogenous retinal detachment) from two medical centers. After processing the samples with an optimized method, we utilized Laser Direct Infrared (LD-IR) spectroscopy and Pyrolysis Gas Chromatography/Mass Spectrometry (Py-GC/MS) to analyze 49 vitreous samples, evaluating the characteristics of MPs within the internal environment of the human eye. Our results showed that LD-IR scanned a total of 8543 particles in the composite sample from 49 individual vitreous humor samples, identifying 1745 as plastic particles, predominantly below 50 μm. Concurrently, Py-GC/MS analysis of the 49 individual samples corroborated these findings, with nylon 66 exhibiting the highest content, followed by polyvinyl chloride, and detection of polystyrene. Notably, correlations were observed between MP levels and key ocular health parameters, particularly intraocular pressure and the presence of aqueous humor opacities. Intriguingly, individuals afflicted with retinopathy demonstrated heightened ocular health risks associated with MPs. In summary, this research provides significant insights into infiltration of MP pollutants within the human eye, shedding light on their potential implications for ocular health and advocating for further exploration of this emerging health risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Substituted para-phenylenediamine quinones (PPD-quinones) are a class of emerging contaminants frequently detected in the aqueous environment. One of them, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q), was found to cause acute toxicities to aquatic species at extremely low environmental levels. The ubiquitousness and ecotoxicity of such pollutants underscore the importance of their transformation and elimination. In this work, we demonstrated effective removals of five PPD-quinones in aqueous environments under UV irradiation, with up to 94% of 6PPD-Q eliminated after a 40-min treatment. By applying high-resolution mass spectrometry (HRMS) non-targeted screening in combination with isotope labeling strategies, a total of 22 transformation products (TPs) were identified. Coupling with the time-based dynamic patterns, potential transformation mechanisms were identified as an •OH-induced photocatalysis reaction involving bond cleavage, hydroxylation, and oxidation. Computational toxicity assessment predicted lower aquatic toxicity of the TPs than their parent PPD-quinones. Our results in parallel evidenced an obvious reduction of PPD-quinones accompanied by the presence of their TPs in the effluent after UV disinfection in real municipal wastewater. This work builds a comprehensive understanding of the fate, transformation products, and related toxicological characteristics of emerging PPD-quinone contaminants in the aqueous environment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Plastics are commonly used by society and their break down into millimeter-sized bits known as microplastics (MPs). Due to the possibility of exposure, reports of them in atmospheric deposition, indoor, and outdoor air have sparked worry for public health. In tropical and subtropical regions all throughout the world, mangroves constitute a distinctive and significant type of coastal wetlands. Mangrove plants are considered to have the effect of accumulating sediment MPs, but the sedimentation of atmospheric MPs has not been reported. In this study, we illustrated the characteristics, abundance and spatial distribution of MPs in different species of mangrove leaves along the Seagull Island in Guangzhou. MPs samples from leaves in five species showed various shapes, colors, compositions, sizes and abundance. Acanthus ilicifolius had an average fallout rate of 1223 items/m 2 /day which has the highest abundance of MPs in all samples. Four shapes of MPs were found in all leaves surfaces including fiber, fragment, pellet, and film, with fiber is the most. The dominant types of MPs in all leaves were cellulose and rayon. Most of the total MPs size were smaller than 2 mm. Clearly, the microstructures of each species leaf surfaces had an impact on its ability to retain MPs. The plants rough blade surfaces and big folds or gullies caused more particles to accumulate and had a higher MPs retention capacity. Overall, our study contributes to a better knowledge of the condition of MPs pollution in atmosphere and the connection between leaves structure and the retention of MPs, which indicates that mangrove plants are promising bioindicator of coastal atmospheric MPs pollution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Plastic aging can cause alterations in the physical and chemical characteristics of plastics, as well as their behavior in the environment. Due to the extremely slow natural aging process, laboratory simulated aging methods have to be used. In this study, non-thermal plasma (NTP) was adopted to investigate the aging process of polypropylene (PP) and polyethylene terephthalate (PET) microplastics. Various analytical instruments, including proton transfer reaction mass spectrometry and single-particle aerosol mass spectrometry, were employed to examine and identify the organic constituents of the gas, liquid, and particle phase degradation products, as well as to monitor the degradation process. The results showed that after 90 min of aging, both PP and PET surfaces showed yellowing, and the carbonyl index of PP increased while that of PET decreased, with an increase in crystallinity. The organic components of reaction products, such as ketones, esters, acids, and alcohols, increased with longer aging times. Gas products mainly contain aromatic hydrocarbons, while particles from aged PET contain compounds with benzene rings and metal elements. Liquid products from aged PP show a significant presence of branched alkanes. Based on this analysis, degradation mechanisms of PP and PET by NTP were proposed. This investigation represents the initial systematically exploration of the release of organic substances during the degradation of microplastics mediated by NTP. It provides significant insights into the detrimental organic compounds emitted during this process, thereby offering valuable information for understanding the environmental and human health implications of natural microplastic degradation. Furthermore, it addressed the requirements for increased attention to the potential environmental risks associated with these harmful components., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Microplastics (< 5 mm) are widely found in organisms and have the potential harm to ecosystems. Despite their widespread prevalence in environments, there is high individual varation in the abundance of microplastics found in individuals of the same species. In the present study, juvenile cichlid fish (Chindongo demasoni) were chosen to determine the ingestion personality for microplastics in the laboratory. The visible implant fluorescent tags were used for individual recognition. The fish were fed with microplastic fiber, pellet, and food for comparison. Our results showed that the observation of the behaviors of fish could be successfully matched with subsequent measurements for each individual through the tag method in microplastic research. The difference in the abundance of fiber (0-27 items/ind.) among fish individuals was also observed in our study. Meanwhile, the abundance of fiber showed a positive correlation with the average speed and covered area of fish, which indicates the degree of activity of fish. Moreover, fish with higher speed or a front position had higher capturing times for pellet. Our results suggest that the swimming behaviors of fish affect their ingestion of microplastics, and active fish had a higher likelihood of ingesting microplastics, which might be one of the reasons for the common phenomena, i.e., great individual differences observed in microplastic studies., Competing Interests: Declaration of Competing Interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work, there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Microplastics could act as vectors for the transport of harmful bacteria, such as pathogens and antibiotic resistance bacteria (ARB), but their combined effects have not been reported yet. Here, ARB Shigella flexneri with sulfonamides resistance and micro-polystyrene (micro-PS) were used to investigate their possible combined effects on the growth and expression of functional genes in Daphnia magna. Results showed that micro-PS colonized with S. flexneri were ingested by D. magna and blocked in their intestine after 24 h exposure. Changes were observed in the life history and morphology of D. magna, as well as the expression of functional genes in all treatments, but with no difference in the survival rate. We also determined the expression of six functional genes involved in energy and metabolism (arginine kinase, AK) and oxidative stress response (thioredoxin reductase, TRxR, catalase, CAT, and glutathione S-transferases, GSTs), as well as in growth, development and reproduction (vitellogenin, Vtg1 and ecdysone receptor, EcR). AK and Vtg1 did not show significant differences, however, EcR was down-regulated and the other three genes (TRxR, CAT, GSTs) were up-regulated in the combined-treated group. Antibiotic resistance gene (ARGs) sul1 was detected when exposed to micro-PS colonized with S. flexneri., suggesting that D. magna could acquire resistance genes through microplastic biofilms. These results indicated that MPs could act as a carrier of ARB to transfer ARGs into D. magna, and affect the life history, morphology, and the expression of related functional genes of D. magna, to adapt to the stress caused by MPs and ARB., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

para -Phenylenediamine quinones (PPD-Qs) are a newly discovered class of transformation products derived from para -phenylenediamine (PPD) antioxidants. These compounds are prevalent in runoff, roadside soil, and particulate matter. One compound among these, N -1,3-dimethylbutyl- n '-phenyl- p -phenylenediamine quinone (6PPD-Q), was found to induce acute mortality of coho salmon, rainbow trout, and brook trout, with the median lethal concentrations even lower than its appearance in the surface and receiving water system. However, there was limited knowledge about the occurrence and fate of these emerging environmental contaminants in wastewater treatment plants (WWTPs), which is crucial for effective pollutant removal via municipal wastewater networks. In the current study, we performed a comprehensive investigation of a suite of PPD-Qs along with their parent compounds across the influent, effluent, and biosolids during each processing unit in four typical WWTPs in Hong Kong. The total concentrations of PPDs and PPD-Qs in the influent were determined to be 2.7-90 and 14-830 ng/L. In the effluent, their concentrations decreased to 0.59-40 and 2.8-140 ng/L, respectively. The median removal efficiency for PPD-Qs varied between 53.0 and 91.0% across the WWTPs, indicating that a considerable proportion of these contaminants may not be fully eliminated through the current processing technology. Mass flow analyses revealed that relatively higher levels of PPD-Qs were retained in the sewage sludge (20.0%) rather than in the wastewater (16.9%). In comparison to PPDs, PPD-Qs with higher half-lives exhibited higher release levels via effluent wastewater, which raises particular concerns about their environmental consequences to aquatic ecosystems.

Tire wear particles (TWPs) are increasingly being found in the aquatic environment. However, there is limited information available on the environmental consequences of TWP constituents that may be release into water. In this study, TWP leachate samples were obtained by immersing TWPs in ultrapure water. Using high-resolution mass spectrometry and toxicity identification, we identified potentially toxic organic substances in the TWP leachates. Additionally, we investigated their toxicity and underlying mechanisms. Through our established workflow, we structurally identified 13 substances using reference standards. The median effective concentration (EC 50 ) of TWP leachates on Scenedesmus obliquus growth was comparable to that of simulated TWP leachates prepared with consistent concentrations of the 13 identified substances, indicating their dominance in the toxicity of TWP leachates. Among these substances, cyclic amines (EC 50 : 1.04-3.65 mg/L) were found to be toxic to S. obliquus. We observed significant differential metabolites in TWP leachate-exposed S. obliquus, primarily associated with linoleic acid metabolism and purine metabolism. Oxidative stress was identified as a crucial factor in algal growth inhibition. Our findings shed light on the risk posed by TWP leachable substances to aquatic organisms., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The interaction of microplastics (MPs) and organic pollutants has recently become a focus of investigation. To understand how microplastic residues affect the migration of organic pollutants, it is necessary to examine the adsorption and desorption behavior of organic pollutants on MPs. In this study, integrated adsorption/desorption experiments and theoretical calculations were used to clarify the adsorption mechanism of 2-hydroxynaphthalene (2-OHN), naphthalene (NAP), phenanthrene (PHE), and pyrene (PYR) by polyvinyl chloride microplastics (PVC-MPs). Based on the phenomenological mathematical models, the rate-limiting step for analyte adsorption onto PVC-MPs was adsorption onto active sites (R 2 = 0.865-0.995). Except for PHE, analyte adsorption isotherms were well described by the Freundlich model (R 2 = 0.992-0.998), and adsorption thermodynamics showed that analyte adsorption on PVC-MPs was a spontaneous exothermic process (ΔH 0 < 0; ΔG 0 < 0). Based on the order of adsorption efficiency of 2-OHN < NAP < PHE < PYR, which is identical to the competitive adsorption experiment, polycyclic aromatic hydrocarbon (PAH) adsorption on PVC-MPs increased as the aromatic ring number increased and the hydroxyl content decreased. The release of 2-OHN (49 %-52 %) from PVC-MPs into the simulated gastrointestinal environment was greater than that of NAP (5.5 %-5.7 %). Theoretical calculations and adsorption tests indicated that hydrophobic interaction was the primary influence on the adsorption of PAHs and their hydroxylated derivatives by PVC-MPs. These findings improve our understanding of MPs' behavior and dangers as pollutant carriers in the aquatic environment and help us develop recommendations for the pollution control of MPs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Pharmaceutical and personal care products (PPCPs) pose a great threat to water environment security. In this study, acyclovir (ACV) was efficiently degraded by thermally activated persulfate (TAP) system. The ACV degradation increased with rising reaction temperature and persulfate dosage. With the existence of inorganic anions and humic acid, ACV removal was retarded to varying degrees. Under strong alkaline condition, it was observed that the degradation of ACV was significantly inhibited. In addition, Kintecus software was employed to simulate ACV removal and achieved a good fit with the experimental results. The contribution rates of main reactive radicals under acidic, neutral, and alkaline conditions were investigated, and the contribution of hydroxyl radical (⋅OH) increased significantly under alkaline condition. The main active species were identified as sulfate radical (SO 4 ⋅ - ) and ⋅OH through quenching experiment, and the second-order reaction rate constants of SO 4 ⋅ - and ∙OH reacted with ACV were calculated to be 9.17 × 10 9  M -1  s -1 and 2.74 × 10 9  M -1  s -1 , respectively. The main degradation pathways included addition of free radicals, oxidation of branch chain and ring opening. The acute and chronic toxicity of intermediates to organisms predicted by ECOSAR were significantly reduced compared with that of ACV., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

A ternary composite (SA/GE@BC) for cadmium removal from wastewater was successfully prepared. The alginate and gelatin were successfully impregnated with biochar (derived from water caltrop shell) to improve the recyclability and adsorption capacity. The prepared SA/GE@BC demonstrated a good removal for cadmium at pH 4.0-7.0 conditions. The cadmium removal increased with increasing SA/GE@BC dosage. The adsorption kinetics process was well consistent with the pseudo-second order model. And the Langmuir model (R 2  > 0.99) best described the isotherm data. The calculated adsorption capacity reached a maximum of 86.25 mg/g. The adsorption was a spontaneous and endothermic process, and elevating temperature favored the removal of cadmium. The alginate-gelatin composition enhanced the number of oxygenated functional groups and exchangeable ions. This enhanced the removal of cadmium by complexation and cation ion exchange. Also, the removal mechanism of cadmium on SA/GE@BC involved electrostatic attraction and π-bond coordination. The saturated SA/GE@BC could be well regenerated by 0.1 M HNO 3 . All these results suggested the preparation of SA/GE@BC could effectively use waste resources to produce highly effective adsorbents for removing cadmium from contaminated water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Plastic pollution is recognized as a major threat to ecosystems in the 21st century. Large plastic objects undergo biotic and abiotic degradation to generate micro- and nano-sized plastic pieces. Despite tremendous efforts to evaluate the adverse effects of microplastics, a comprehensive understanding of the toxicity of nanoplastics remains elusive, especially at the protein level. To this end, we used isobaric-tag-for-relative-and-absolute-quantitation-based quantitative proteomics to investigate the proteome dynamics of the soil nematode Caenorhabditis elegans in response to exposure to 100 nm polystyrene nanoplastics (PS-NPs). After 48 h of exposure to 0.1, 1, or 10 mg/L PS-NPs, 136 out of 1684 proteins were differentially expressed and 108 of these proteins were upregulated. These proteins were related to ribosome biogenesis, translation, proteolysis, kinases, protein processing in the endoplasmic reticulum, and energy metabolism. Remarkably, changes in proteome dynamics in response to exposure to PS-NPs were consistent with the phenotypic defects of C. elegans. Collectively, our findings demonstrate that disruption of proteome homeostasis is a biological consequence of PS-NPs accumulation in C. elegans, which provides insights into the molecular mechanisms underlying the toxicology of nanoplastics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Polycyclic aromatic hydrocarbons (PAHs) are frequently released in aqueous phase by oil spill or from other sources, and photochemical oxidation is one of their major weathering processes. In this study, the photochemical behavior of phenanthrene (PHE, as a representative PAH) were studied and the effects of nitrogenous compounds were evaluated. The results showed that nitrate was an effective photosensitizer for improving the photodegradation of PHE, but the promoting effect was less effective in seawater due to the presence of halogen ions; the ammonia played a negligible role on PHE degradation. The photochemical ionization was a key process for PHE degradation, it can be retarded due to the quenching of triplet excited state by dissolved oxygen, and the inhibition was most prominent in fresh water. The presence of nitrate increased the steady state concentration of •OH from 2.08 × 10 -15 M to 1.04 × 10 -14 M in fresh water, and from 1.5 × 10 -16 M to 2.08 × 10 -15 M in seawater. The secondary-order reaction rate constant between PHE and •OH (k •OH,PHE ) was determined as 5.70 × 10 9 M -1 s -1 . Similar trend was observed for 1 O 2 . The contribution of •OH to PHE removal was more prominent in fresh water than in seawater due to the quenching effects of halogen, and the increasing of nitrate enlarged the contribution of •OH. Two possible PHE degradation pathways were proposed based on GC-MS analysis and DFT calculation. The Quantitative Structure-activity Relationship (QSAR) evaluation showed that some degradation intermediates were more toxic than PHE, but the total environmental risk was still diminished due to the low percentage of toxic intermediates. This study provided theoretical and experimental insights into the influence of nitrogenous compounds on the photodegradation of PHAs in water environment., Competing Interests: Declaration of Competing Interest On behalf of all authors, I declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with this work., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Water quality evaluation and degrading factors identification are crucial for predicting water quality evolution trends in an urban river. However, under the coupling of multiple factors, these targets face great challenges. The water quality status response to multiple anthropogenic activities in an urban river was evaluated and predicted based on comprehensive assessment methods and random forest (RF) model. We found that the distribution of each physicochemical parameter exhibits an obvious spatial clustering. The mean pollution level and trophic status of the urban river are medium pollution (water quality index = 59.79; Nemerow's pollution index = 2.00) and light eutrophication (trophic level index = 57.30). The water quality status is sensitive to anthropogenic activities, showing the following order of TLI and NPI values: residential district > industrial district > agricultural district and downtown > suburbs > countryside. According to the redundancy analysis, constructed land (F = 15.90, p < 0.01) and domestic sewage (F = 14.20, p < 0.01) evinced as the crucial factors that aggravated the water quality pollution level. Based on the simulation results of the RF model (variation explained = 94.91%; R 2 = 0.978), improving domestic sewage treatment standards is the most effective measure to improve the water quality (increased by 40.3-49.3%) in residential and industrial districts. While in a suburban district, improving the domestic sewage collection rate has more effectively (23%) than those in the residential and industrial districts. Conclusively, reducing exogenous pollution input and improving domestic sewage treatment standards are vital to urban river restoration. Clinical trial registration Not applicable., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Phosphorus speciation in the sediments is regulated by a series of physicochemical and microbial processes, and directly affects water phosphorus pool. However, the influence of culture activities and microbial metabolism on the sedimentary phosphorus speciation is poorly studied. In this study, we compared the abundance of distinguishable phosphorus phases and other physicochemical properties of sediments from oyster-farming areas and reference areas. The Geochip 5.0 technique was introduced to reveal the microbiological mechanisms of phosphorus metabolic alteration. The results showed that oyster culture enhanced the bioavailability of phosphorus in sediments. The free organic phosphorus was reduced significantly, whereas the free inorganic phosphorus and iron-bound phosphorus greatly increased in the oyster culture area (P ≤ 0.05). Moreover, the results of Geochip showed that the oyster culture reshaped the microbial network structure in sediments, with typical phosphate-solubilizing and phosphorus-accumulating microbes being enriched by 17.76% and 10.60%. The abundance of functional genes related to the main phosphorus cycle pathways were also significantly increased (P ≤ 0.05) in the culture area compared to the reference area. This work suggested that oyster culture can greatly improve the microbial phosphorus metabolism and provided insights into the environmental recovery and reconstruction from marine aquaculture activities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In this study, a schwertmannite-like mineral was synthesized for the removal of lead (Pb) and chromium (Cr) from contaminated wastewater. A shaking flask test was performed (150 r/min, 1 h) with FeSO 4 ·7H 2 O, H 2 O 2 , Na 2 SiO 3 , and CaCl 2 added for the mineral synthesis reaction. Results show that optimal performance was achieved with the addition of 1.24 g/L FeSO 4 ·7H 2 O, 0.75 g/L H 2 O 2 , 1.27 g/L Na 2 SiO 3 , and 0.44 g/L CaCl 2 at a water temperature of 28 °C, with coexisting ion (Na + , K + , Mg 2+ ) concentrations of 1.50 mmol/L and 0.50 mmol/L EDTA as a complexing agent. Under these optimal conditions, maximum Pb and Cr removal rates of 95.08% and 97.99%, respectively, were achieved within the first 1 min of the mineral synthesis reaction, with the synthesis reaction completed by 6 min. The simultaneous removal of Pb and Cr during the schwertmannite-like material synthesis process occurred via electrostatic adsorption and coprecipitation. When the concentration of the complexing agent was increased from 0.75 to 6.03 mmol/L, the Pb removal rate decreased from 71.88 to 35.45%, and the Cr removal rate decreased from 95.13 to 75.07%, showing that Pb and Cr removal exhibited significant levels of inhibition. In contrast, varying reaction temperatures induced no significant differences. The Pb and Cr dissolution rates from Pb/Cr-containing schwertmannite-like minerals were 8.18% and 2.86% after 40 days, respectively. Therefore, the risk of secondary dissolution of heavy metals is small., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Microplastics (MPs; <5 mm) in the biosphere draws public concern about their potential health impacts. Humans are potentially exposed to MPs via ingestion, inhalation, and dermal contact. Ingestion and inhalation are the two major exposure pathways. An adult may consume approximately 5.1 × 10 3 items from table salts and up to 4.1 × 10 4 items via drinking water annually. Meanwhile, MP inhalation intake ranges from 0.9 × 10 4 to 7.9 × 10 4 items per year. The intake of MPs would be further distributed in different tissues and organs of humans depending on their sizes. The excretion has been discussed with the possible clearance ways (e.g., urine and feces). The review summarized the absorption, distribution, metabolic toxicity and excretion of MPs together with the attached chemicals. Moreover, the potential implications on humans are also discussed from in vitro and in vivo studies, and connecting the relationship between the physicochemical properties and the potential risks. This review will contribute to a better understanding of MPs as culprits and/or vectors linking to potential human health hazards, which will help outline the promising areas for further revealing the possible toxicity pathways., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Biological upgradation (BU) process was proposed, with the goal of converting the molecular structure, for improving the coagulation effect on humic substances (HS) in effluent organic matter from the membrane bioreactor of a leachate treatment system. Enhancement of coagulation effect was observed with the improvement of chemical oxygen demand and HS removal efficiency from 45.5% and 56.5% to 80.0% and 92.6% (Fe dosage was 400 mg·L -1 ), respectively, which was approximately 30-40% higher than the other available researches. Variations in molecular weight (MW) and carboxyl contents of fulvic acid (FA) and humic acid (HA) were analysed by size exclusion chromatography coupled with dissolved organic carbon detection, potentiometric titration and Fourier transform infrared spectroscopy. The obtained results indicated that BU process led to the growth of MW of HS, of which the larger MW (1650 Da) FA and HA raised from 19.07 and 0.34 mgC·L -1 to 71.67 and 1.58 mgC·L -1 , respectively, as well as increases in the carboxyl contents of FA and HA from 6.70 and 6.28 meq·gC -1 to 11.84 and 8.71 meq·gC -1 , respectively. Because of this, a stronger binding effect between Fe and HS might be formed that improved the coagulation effect.

The microbial communities associated with microplastics (MPs) and their ambient environments have received wide attention. Although previous studies have reported the differences of microbial communities between MPs and natural environment or substrates, the effects of MPs on microbial balance and functions in ambient water remain unclear, particularly for aquaculture water. Here, we investigated the MPs pollution in farm ponds of grass carp located in the Foshan City of Guangdong Province and reported the distinction of bacterial structures, functions, and complexity between microbiota on MPs and in water. MPs with an average abundance of 288.53 ± 74.27 items/L in pond water were mostly fibers and cellulose, mainly transparent and in size of 0.5-1 mm. Structures and functions of bacterial communities on MPs significantly differed from that in pond water. A large number of enriched or depleted OTUs on MPs compared with water belong to the phylum Proteobacteria, the predominant phylum in microbial communities on MPs and in water. Some species included in the phylum Proteobacteria have been shown to be cellulose-degrading and pathogenic. Microbiota on MPs exhibited higher species richness and diversity as well as a more complex network than that in water, illustrating MPs as a distinct habitat in the aquaculture system., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Recently, metal-organic frameworks (MOFs), which are porous inorganic-organic hybrid materials consisting of metal ions (clusters or secondary building units) and organic ligands through coordination bonds, have attracted wide attention because of their high surface area, huge ordered porosity, uniform structural cavities, and excellent thermal/chemical stability. In this work, durian shell biomass carbon fiber and Fe 3 O 4 functionalized metal-organic framework composite material (durian shell fiber-Fe 3 O 4 -MOF, DFM) was synthesized and employed for the adsorption removal of methylene blue (MB) from wastewater. The morphology, structure, and chemical elements of the DFM material were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electron microscope (TEM), and X-ray photoelectron spectroscope (XPS) techniques. Adsorption conditions such as pH, adsorption time, and temperature were optimized. The adsorption isotherm and kinetics results show that the adsorption process of DFM material to MB is more in line with the Freundlich model and pseudo-second-order kinetic model. Using these models, the maximum adsorption capacity of 53.31 mg/g was obtained by calculation. In addition, DFM material could be easily reused through an external magnet and the removal rate of MB was still 80% after five adsorption cycles. The obtained results show that DFM composite material, as an economical, environmentally friendly, recyclable new adsorbent, can simply and effectively remove MB from wastewater.

As a kind of emerging pollutant, microplastics (MPs) play an important role as a carrier for pollutant migration in the water environment. Carried by the MPs, benzotriazoles, and benzothiazoles (collectively referred to as BTs) 1 are ubiquitous water contaminants. In this paper, the adsorption behavior of BTs on polyvinyl chloride (PVC) MPs was first studied systematically to explain the adsorptive mechanisms and the consequential pollution caused by the absorption-desorption process. The studies on kinetics, isotherms, and thermodynamics revealed that the adsorption of BTs on PVC MPs was a multi-rate, heterogeneous multi-layer, and exothermic process, which was affected by external diffusion, intra-particle diffusion, and dynamic equilibrium. The factors including pH, salinity, and particle size also influenced the adsorption process. In the multi-solute system, competitive adsorption would occur between different BTs. The desorption of BTs from PVC MPs was positively associated with the increase of adsorption amount. Based on the results, the adsorption mechanisms of PVC MPs were clarified, involving hydrophobic interaction, electrostatic force, and non-covalent bonds. It was demonstrated that BTs in the water environment could most probably be accumulated and migrated through MPs, and eventually carried into organisms, posing an increased risk to the ecological environment., Competing Interests: Declaration of competing interest No competing economic interests or personal relations need to be declared., (Copyright © 2022. Published by Elsevier B.V.)

The adverse impact of microplastics (MPs) on gut microbiota within aquatic animals depends on the overall effect of chemicals and biofilm of MPs. Thus, it is ideal to fully understand the influences that arise from each or even all of these characteristics, which should give us a whole picture of consequences that are brought by MPs. Harmful effects of MPs on gut microbiota within aquatic organisms start from the ingestion of MPs by aquatic organisms. According to this, the present review will discuss the ingestion of MPs and its following results on gut microbial communities within aquatic animals, in which chemical components, such as plastic polymers, heavy metals and POPs, and the biofilm of MPs would be involved. This review firstly analyzed the impacts of MPs on aquatic organisms in detail about its chemical components and biofilm based on previous relevant studies. At last, the significance of field studies, functional studies and complex dynamics of gut microbial ecology in the future research of MPs affecting gut microbiota is discussed., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Plastic discharged into the environment would break down into microplastics (MPs). However, the possible impact of MPs on heavy metals in the aquatic sediment remains unknown. In order to evaluate the potential role of MPs as carriers of coexisting pollutants, the adsorption capacity of lead ions from sediment onto aged degradable and conventional MPs were investigated as a function of lead ions concentration, contact time, temperature, MPs dosage, aging time, and fulvic acid concentration. MPs were exposed to UV to obtain aged polyethylene (A-PE) and aged polylactic acid (A-PLA). The aging treatment increased the oxygen content, specific surface area and hydrophilicity of MPs. The adsorption capacity of A-PE for Pb(II) in sediment increased from 10.1525 to 10.4642 mg g -1 with the increasing aging time. However, the adsorption capacity of A-PLA for Pb(II) in sediment decreased from 9.3199 to 8.7231 mg g -1 with the increasing aging time. The adsorption capacity of MPs in sediment for Pb(II) was in the following order: A-PE > PLA > PE > A-PLA. Fulvic acid could promote the adsorption of Pb(II) by MPs in sediment. These results indicated that the aging process of the plastics in the environment would affect its role as a carrier of coexisting pollutants., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Triclocarban (TCC) is considered an endocrine disruptor and shows antagonist activity on thyroid receptors. In view of the report that thyroid hormone signaling mediates retinal cone photoreceptor specification, we hypothesize that TCC could impair visual function, which is vital to wildlife. In order to verify our hypothesis, we assessed alteration in the retinal structure (retinal layer thickness and cell density), visually-mediated behavior, cone and rod opsin gene expression, and photoreceptor immunostaining in zebrafish larvae exposed to TCC at environmentally realistic concentrations (0.16 ± 0.005 µg/L, L-group) and one-fifth of the median lethal concentrations (25.4 ± 1.02 µg/L, H-group). Significant decrease in eye size, ganglion cell density, optokinetic response, and phototactic response can be observed in the L-group, while the thickness of outer nuclear layer, where the cell bodies of cone and rod cells are located, was significantly reduced with the down-regulation of critical opsin gene (opn1sw2, opn1mw1, opn1mw3, opn1lw1, opn1lw2, and rho) expression and rhodopsin immunofluorescence in the H-group. It should be noted that TCC could affect the sensitivity of zebrafish larvae to red and green light according to the results of behavioral and opsin gene expression analysis. These findings provide the first evidence to support our hypothesis that the visual system, a novel toxicological target, is affected by TCC. Consequently, we urgently call for a more in-depth exploration of TCC-induced ocular toxicity to aquatic organisms and even to humans., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Pollutant-attached microplastics have received increasing attention in recent years. However, information regarding the influence of hydroxyl group content of pollutants on the adsorption and desorption behavior is unclear, which affects their fate and risks in the aquatic environment. In this study, we investigated the adsorption and desorption behavior of anthracene (ANT) and its hydroxy derivatives (OHAs), including 2-hydroxyanthracene (MOHA), 2,6-dihydroxyanthracene (DOHA), and 1,8,9-trihydroxyanthracene (TOHA) on polyvinyl chloride (PVC) microplastics, and their interaction mechanism through the batch, characterization, and computational experiments. The results showed that the adsorption of ANT and OHAs on PVC microplastics conformed to the pseudo-second-order kinetic model and was exothermic spontaneously. The adsorption efficiency on PVC followed the order of ANT > MOHA > DOHA > TOHA, indicating that increase in hydroxyl group substitution degree will inhibit pollutant adsorption on PVC microplastics. Conversely, the release amounts of MOHA from PVC into simulated gastric fluids were higher than those of ANT. Experimental and computational results suggested that the affinity of ANT/OHAs to PVC microplastics was the most likely outcome in hydrophobic effect, electrostatic repulsion, and CH-π interaction forces. These findings help elucidate the mechanisms of pollutant adsorption on microplastics and evaluate the risk of pollutant-attached microplastics in the aquatic environment., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The continuous release of manufactured nanomaterials (MNMs) to environments raised concerns on their combined toxicological risks with co-existing contaminants, since MNMs might severely alter the environmental behavior and fate of the contaminants. In this study, the combined toxicity of nano-sized titanium dioxide (nTiO 2 ) and cadmium (Cd 2+ ) to the green alga Scenedesmus obliquus and the underlying physicochemical mechanisms were investigated for the first time at different concentration ratios of Cd 2+ to nTiO 2 to closely mimic the realistic environment scenarios where the concentration ratios of nTiO 2 to other contaminants are constantly changing. Our results suggested that under the co-exposure to different concentration ratios of Cd 2+ to nTiO 2 , the co-exposure contaminants exhibited three different combined toxicity modes (antagonistic, partially additive, and synergistic). Specifically, antagonistic combined toxicity was observed under co-exposure to a low concentration ratio of nTiO 2 to Cd 2+ as the absorption by nTiO 2 decreased the bioavailability of Cd 2+ . However, the partially additive and synergistic combined toxicity occurred when the proportion of nTiO 2 in the co-exposure system was relatively high, which would mechanically and/or oxidatively damage the alga cell structures. Even worse, as a carrier of Cd 2+ , nTiO 2 enhanced the amount of Cd 2+ entering cells, which significantly enhanced the toxicity of Cd 2+ to algae. Overall, we demonstrated that concentration ratios of nTiO 2 to Cd 2+ play an important role in determining the combined toxicity mode, which would provide a novel reference to environmental and health risk assessment of co-exposure to conventional pollutants and MNMs., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Hexachlorobutadiene, pentachloroanisole, and chlorobenzenes are regulated to control their release into the environment. There is little information regarding the distribution and risks of these pollutants in Chinese rivers. Therefore, we selected a prosperous agricultural and industrial region in South China as our study area and investigated the contamination profiles and risks of these pollutants in sediment and fish tissue samples. The results showed that, when compared with their levels in sediment, these lipophilic pollutants tended to accumulate in fish tissues in the following order: liver > brain > muscle. Some trichlorobenzene was found to be the result of reductive dechlorination of higher chlorinated benzenes. Hexachlorobutadiene and hexachlorobenzene could pose medium risks at certain sampling sites, but in general, almost no risk was found to the ecosystem. When the estimated daily human intakes of analytes through fish consumption were calculated for different age groups, the results suggested the analytes were unlikely to be a serious health concern for human. Our results could be used to update the existing data on the occurrence of these pollutants in the aquatic environment and to provide information for further pollution control by the local government., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Intensified disinfection of wastewater during the COVID-19 pandemic increased the release of toxic disinfection by-products (DBPs). However, studies relating to the ecological impacts of DBPs on the aquatic environment remain insufficient. In this study, we comparatively investigated the toxicities and ecological risks of 17 typical, halogenated DBPs to three trophic levels of organisms in the freshwater ecosystem, including phytoplankton ( Scenedesmus sp.), zooplankton ( Daphnia magna ), and fish ( Danio rerio ). Toxicity of DBPs was found to be species-specific: Scenedesmus sp. was the most sensitive to haloacetic acids, while D. magna was the most sensitive to haloacetonitriles and trihalomethanes. Specific to each DBP, toxicities were also related to their classes and substituted halogen atoms. Damage to photosystems and oxidative stress served as the potential mechanisms for DBPs toxicity to microalgae. The different sensitivities to DBPs indicate that a battery of bioassays with organisms at different trophic levels is necessary to determine the ecotoxicity of DBPs. Furthermore, the ecological risks of DBPs were assessed by calculating the risk quotients (RQs) based on toxicity data from multiple bioassays. The cumulative RQs of DBPs to all the organisms were greater than 1.0, indicating high ecological risks of DBPs in wastewater effluents.

Climbazole (CBZ) ubiquitously detected in the aquatic environment may disrupt fish reproductive function. Thus far, the previous study has focused on its transcriptional impact of steroidogenesis-related genes on zebrafish, but the underlying toxic mechanism still needs further investigation at the metabolic level. In this study, adult zebrafish were chronically exposed to CBZ at concentrations of 0.1 (corresponding to the real concentration in surface water), 10, and 1000 μg/L and evaluated for reproductive function by egg production, with subsequent ovarian tissue samples taken for histology, metabolomics, and other biochemical analysis. After 28 days' exposure, fecundity was significantly decreased in all exposure groups, with the inhibition of oocytes in varying developmental stages to a certain degree. The decrease in retinoic acid and sex hormones, down-regulated genes important in steroidogenesis, and increase in oxidized/reduced glutathione ratio and occurrence of apoptotic cells were observed in zebrafish ovaries following exposure to CBZ even at environmentally realistic concentrations, suggesting that alternations in steroidogenesis and oxidative stress can play significant roles in CBZ-triggered reproductive toxicity. Besides, mass spectrometry imaging analysis validated the results from metabolomics analysis. Our findings provide novel perspectives for unveiling the mechanism of reproductive dysfunction by CBZ and highlight its risk to fish reproduction., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Engineering nanoparticles (NPs) could act as accumulator and carrier of co-contaminants, affecting their fate and toxicity in environments. However, the effects of NPs on the bioaccumulation and trophic transfer of co-contaminants through the food chain and the ensuing effects on higher predators are unclear. In the present study, we investigated the effects of titanium dioxide nanoparticles (nTiO 2 ) on the trophic transfer of phenanthrene (Phe) from prey Artemia salina to predator Scophthalmus maximus. We also evaluated the ensuing toxic performance of Phe in S. maximus after been transferred from A. salina in the presence and absence of nTiO 2 . The presence of nTiO 2 significantly (p < 0.05) increased Phe accumulation in A. salina with higher bioconcentration factor (BCF) up to 90.9 than that of 38.6 in Phe exposure along. After trophic transfer, nTiO 2 (1 mg/L) also promoted the bioaccumulation of Phe (1 μg/L) in predator S. maximus from 4.17 mg/kg to 7.85 mg/kg (dry weight). However, nTiO 2 did not enhance the trophic transfer of Phe from A. salina to S. maximus since the biological magnification factor (BMF) decreased from 0.13 to 0.08. Nevertheless, the nTiO 2 -enhanced bioaccumulation of Phe did enhance Phe toxicity performance in predator S. maximus after trophic transfer, showing significant (p < 0.05) growth inhibition and changes of nutrient status in the predator, compared to those of the control. Further physio-biochemical investigations suggested that oxidative stress and inhibition of digestive functions might explain the growth inhibition in treatment with nTiO 2 + Phe. This study demonstrates the first evidence that NP-enhanced bioaccumulation and toxic performance of co-existing pollutants across trophic transfer, which poses potential risks to marine ecosystems, and ultimately human health by seafood consumption., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Three-dimensional graphene aerogel materials used for treatment of oily wastewater with sophisticated composition remains a challenge due to volume shrinkage, resulting in single-function and low adsorption capacity. In this work, renewable Enteromorpha was introduced into the graphene aerogel via facile hydrothermal-freeze casting treatment, forming the compression, ultralight and amphiphilic adsorbent for oil spill cleanup and water pollution remediation. Meanwhile, further freeze casting avoids aerogel collapse for capillary tension during drying and produce more hierarchical pores. As for oil spill clean up, the Enteromorpha modified graphene aerogel (EGA) exhibits excellent adsorption capacity towards oil and organic solvents than pristine graphene aerogel (GA). Even after several cycles by compression and heat treatment, it still has a stable adsorption capacity for oil and organic solvents. The EGA also showed high ability to absorb water-soluble pollutants, such as dyes through hydrogen bonding and electrostatic reactions between dye molecules and aerogel. The facile strategy to fabricate the Enteromorpha-based amphiphilic EGA broadens the applications in water treatment through the high-value utilization of Enteromorpha., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

To assess the potential effects of microplastics (MPs) on gut microbiome, a simple investigation of gut microbial structure is not sufficient, and the function and association of gut microbial structure with host health should also be taken into account. Here, the effects of two particle sizes (2 and 200 μm) of polystyrene MPs (PS-MPs) on the gut microbiota of medaka were evaluated following oral administration at 0.3 and 3.0 μg/mg for 28 days. No change in body length and gut histopathology damage were observed. However, the exposure to PS-MPs significantly decreased fish body weight and disrupted the liver anti-oxidative status. The PS-MPs caused a shift in the gut microbial structure of medaka accompanied by changes in community function, including significant environmental stress, increased carbon degradation/fixation activities, and partially modified nitrogen/phosphorus/sulfur metabolic abilities. Furthermore, the PS-MPs exposure disturbed the glycolipid/tyrosine/energy metabolism and the endocrine balance. A potential correlation between the gut microecology and host response to PS-MPs exposure was also observed. These results indicated that the PS-MPs may contribute to gut-liver axis disruption, which could be the underlying toxicological mechanisms of PS-MPs exposure. This work has improved our knowledge about the relationship between gut microbiota dysbiosis and host metabolic disorders following MPs exposure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Polybrominated diphenyl ethers (PBDEs) are a class of widely used flame retardants, and their residue in the environment may threaten the ecosystem and human health. The neurodevelopmental toxic effects of PBDEs have been verified in previous studies, but the mechanisms are still unclear. Behavioral analysis and transcriptomics were performed in this study to assess the neurodevelopmental toxic effects of PBDEs on zebrafish embryos and larvae, and the potential mechanisms. The embryos were collected after fertilization and exposed to control (0.05% DMSO), 10, 50, 100 (ug/L) 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) for 7 days. The locomotion parameters of larvae were recorded and analyzed by a behavioral analysis system (EthoVision XT, Noldus). Enrichment of functions and signaling pathways of differentially expressed genes (DEGs) were analyzed by GO and DAVID database. The comparison with the control group showed adverse developments such as low hatching rate, high mortality rate, alterative heart rate, and abnormal spontaneous tail coiling frequency of embryos (24hpf). For the zebrafish larvae, behavioral analyses results suggested decreased activities and movements of the treatment in the light-dark period at 120, 144 and 168hpf, especially the 50 and 100μg/L groups. The affected functions included steroid hormone regulation, neuro regulation, circadian regulation, cardioblast differentiation, immune-related regulation. The enrichment of KEGG pathways were Hedgehog signaling (Shh), Toll-like receptor signaling, FoxO signaling, and Steroid biosynthesis pathway. Hedgehog signaling pathway was further verified via RT-qPCR for its major role in the development of neurogenesis. The mRNA levels of Shh pathway indicated the inhibition of Shh signal in our study since shha, patched1, gli1 and gli2 genes were significantly down-regulated. In summary, PBDEs might influence the neurodevelopment of zebrafish in the early life stage by multiple toxic signaling pathways alteration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Bisphenol A (BPA) is a well-known xenobiotic endocrine disrupting chemical, with estrogenic activity and many other potential biological effects. Although multiple toxicities have been reported for BPA, molecular mechanisms underlying the transgenerational toxic effects of BPA are still underestimated., Methods: Parental F0 fish were exposed to 1.0 μM BPA or control (0.1% DMSO, v/v) for 7 days. Eggs (F1) were collected and kept in control medium until 4.5 or 120 h post fertilization (hpf). RNA sequencing (RNA-seq) was conducted on embryos and larvae, to discover differentially expressed genes (DEGs), and then KEGG pathway, GO enrichment and GSEA were performed to interpret functional ontology. Histopathology was performed to explore the morphological and structural alterations in liver tissues of zebrafish larvae (120 hpf) after parental BPA exposure., Results: Parental BPA exposure induced global transcriptomic changes in zebrafish embryos and larvae. For embryos, epigenetic regulation genes were decidedly affected, highlighted epigenotoxicity might involve in the transgenerational effects during embryogenesis and early development. By further investigation on its delayed effects, our RNA-Seq data of larvae suggested ROS metabolic process, apoptosis, p53 and MAPK signaling pathway were concentrated, indicating defensive cellular processes still involved in protecting against BPA toxicity. Furthermore, parental BPA-treated larvae manifested hepatic injury by histopathological analysis., Conclusions: Parental BPA exposure led to global transcriptomic changes involved in epigenetic regulation, oxidative stress, apoptosis and DNA damage of offspring. These findings advanced the field of the parental-mediated subsequent generational toxic effects of BPA., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The increasing use of nanoscale TiO 2 particles (nTiO 2 ) and their subsequent leakage into aquatic environments poses a threat to the ecosystem. One major concern is that nTiO 2 may alter the environmental behaviors of arsenic (As) and disrupt the equilibrium of As accumulation and speciation in organisms. In this study, we investigated the effects of nTiO 2 on the bioaccumulation and biotransformation of As(V) in the mussel Perna viridis . Exposure to nTiO 2 significantly increased As accumulation in mussels. Our As speciation analysis demonstrated that nTiO 2 treatment increased the proportion of inorganic As and reduced that of organic As, displaying inhibitory effects on the methylation and detoxification of inorganic As in mussels. Analysis of enzyme systems related to As metabolism in mussels demonstrated that nTiO 2 might limit the methylation of inorganic As by suppressing the GST activity and GSH content. The strong adsorption capacity and weak desorption rate of As by nTiO 2 , which could result in the disruption of As distribution and decrease of the amount of As involved in biotransformation, might serve as another mechanism to the limition on As methylation in mussels. Moreover, exposure to nTiO 2 disturbed the osmotic adjustment system in mussels by reducing arsenobetaine and Na + -K + -ATPase activity, resulting in enhanced toxicity of As after coexposure. The findings indicate, for the first time, that nTiO 2 can block the transformation and detoxification of As in mussels, which would increase the risk of As to marine animals and even humans via the food chain, and may disrupt the biogeochemical cycle of As in natural environments.

As the industries advances at a fast pace, efficient and simultaneous removal of both heavy metals and organics from aqueous is essential to protecting public human health and environment. In this work, we used pyrite as reductant and catalyst for simultaneously reducing Cr(VI) and activating persulfate (PS) to degrade acid orange 7 (AO7). The results indicated that the simultaneous removal rate of AO7 and Cr(VI) by pyrite-PS was up to 100% within 60 min under acidic conditions. However, There was a competitive relationship between PS activation and Cr(VI) reduction for robbing Fe 2+ . At beginning of the reaction, the limited Fe 2+ firstly activated persulfate rather than reduce Cr(VI). The effect of dosage of pyrite and PS on Cr(VI) reduction was more significant than that on AO7 degradation. Increased pyrite dosages from 1g·L -1 to 6 g L -1 resulted in enhanced Cr(VI) removal, and excessive PS (more than 0.4 g L -1 ) was not beneficial to Cr(VI) removal. Electron paramagnetic resonance (EPR) spectroscopy and radical scavenger studies demonstrated that sulfate (SO 4 - ·), singlet oxygen ( 1 O 2 ) and superoxide radical (·O 2 - ) were the crucial reactive oxygen species (ROS) in the pyrite-PS system rather than hydroxyl radical (·OH). This study showed that the pyrite-PS system could simultaneously remove AO7 and Cr(VI), which provided a new idea for the actual wastewater treatment., (Copyright © 2020 Elsevier Inc. All rights reserved.)

To regulate the water level and minimize the occurrence of water eutrophication in shallow lakes, dams and gates are often constructed in rivers. However, this practice may result in a deterioration of water quality in some estuaries. In the present study, using the correction of Nemerow pollution index (CNPI) and a redundancy analysis (RDA), water samples from different dammed rivers around Taihu Lake were compared to assess the pollution risk and identify the factors responsible for water eutrophication. The average total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC) concentrations, and chemical oxygen demand (COD Mn ) were 2.45 ± 2.28, 0.08 ± 0.06, 43.01 ± 18.75, and 10.78 ± 4.86 mg L -1 , respectively. The CNPI values indicated that approximately 76.47% of the estuarine water was moderately polluted (1 < CNPI < 7.28). A positive correlation was observed between dam construction and nutrient concentrations (e.g., r TN = 0.38, p < 0.05; r TP = 0.89, p < 0.01). Under the effects of dam construction, land use change, estuary shape, and meteorological conditions, there was a clear spatial variation of the TN concentrations. Dams that were closed all year round accelerated the TN accumulation in the water around them. The pollution risk in a trumpet-shaped estuary was higher than that in other regions (t = 2.92, p = 0.02). Endogenous release of pollutants was an important factor that may have a priming effect on algal blooms and should be given more attention. In Wuli Lake, exogenous pollution was the dominant pollutant source. A total of 74.49% of the nitrogen losses with the runoff into the estuarine water in 2018 were derived from urban domestic sewage and constructed land, with the load being 4.40 times higher than in 2000. The RDA results revealed that dam construction was the main factor (43.70%) affecting water quality, while meteorological conditions, land use types, estuary shape, and other factors contributed 56.30%. Scientific regulation and control of dam operation is important to protect the water environment of Taihu Lake.

Pharmaceutical and personal care products (PPCPs) have been the focus of increasing concern in recent decades due to their ubiquity in the environment and potential risks. Out-of-date PPCPs are usually discharged into municipal solid wastes (MSWs), enter the leachates in MSW landfills, and have serious adverse effects on the surrounding water environment. However, the occurrence and removal of PPCPs from landfill leachates have rarely been examined to date. This lack of knowledge makes the landfill an underestimated source of PPCPs in the environment. In this review, we collected the relevant publications of PPCPs in landfill leachates, systematically summarized the occurrence of PPCPs in landfill leachates globally, evaluated the removal performances for various PPCPs by different types of on-site full-scale leachate treatment processes, and assessed the impacts of landfill leachates on PPCPs in the adjacent groundwater. In particular, influencing factors for PPCPs in landfill leachates, including the physicochemical properties of PPCPs, climate conditions, and characteristics of landfill sites (i.e., landfill ages) as well as sociological factors (i.e., economic development), were extensively discussed to understand their occurrence patterns. Future perspectives were also proposed in light of the identified knowledge gaps. To the best of our knowledge, this is the first review regarding the occurrence and removal of PPCPs from landfill leachates worldwide.

The non-point source pollution of drinking water source areas is a global issue which is mainly caused by unreasonable management of the commercial forests growing in the upstream areas. However the occurrence and specific mechanism of runoff pollution in these areas have not been approached. In order to clarify the factors influencing the non-point source pollution in the area, the test plot in Fushi Reservoir watershed covered by Phyllostachys edulis plantations with pure and modified stands was chosen, and the characteristics of soil chemical properties, enzyme activities and the coupling between soil factors and surface runoff of were initially analyzed, the relationship between soil factors and surface runoff pollutants was examined using redundancy analysis. The results showed that pH, soil nitrate reductase (S-NR) and catalase (S-CAT) were the key factors affecting the differentiation of water quality in surface runoff. The total nitrogen (TN) concentration in surface runoff was positively correlated with S-NR but negatively correlated with pH, TN and alkali-hydrolyzed nitrogen (AN) concentrations in soil. The total phosphorus (TP) concentration was negative correlation with soil pH and TP. In addition, the permanganate index (COD Mn ) concentration has positive correlation with urease (S-UE), acid phosphatase (S-ACP) and organic matter (SOM) in soil. These results suggest that soil enzyme activities are more sensitive than soil nutrient status, and could be used as indicators of non-point source pollution assessing. Moreover, pollution in this area could be effectively controlled by enhancing vegetation coverage and ameliorating soil environment., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

In this study, we report a new class of rhodamine-based fluorescent sensors for highly selective and sensitive detection of Pd 2+ ions in aqueous medium. A rhodamine-based palladium sensor RPS and a coumarin-rhodamine Förster resonance energy transfer (FRET)-pair based palladium sensor FPS were synthesized with the designed podand ligand for Pd 2+ ion recognition. They showed both colorimetric change and fluorometric change in the presence of Pd 2+ ion due to the opening of their spirolactam rings. Both chemosensors are highly selective to Pd 2+ over the other 24 different metal ions and they are selective to palladium species in +2 oxidation state, RPS showed a 70-fold fluorescent turn-on while FPS showed a 1.75-fold ratiometric change at I 599 /I 470 . Furthermore, RPS showed low cell cytotoxicity and it was successfully used to image Pd 2+ in BEAS-2B lung epithelial cells. © 2019 Elsevier Science. All rights reserved., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Extensive application of fullerene nanoparticles (nC 60 ) leads to potential environmental pollution. The acute toxic effects of nC 60 have been largely investigated, but studies of behavioural and chronic toxicity at sublethal doses are still rare and the underlying molecular mechanisms remain unknown. The present study investigated behavioural and chronic toxicity of nC 60 to Daphnia magna. The results showed that, in response to nC 60 exposure, hopping, heartbeat frequencies and feeding ability of D. magna decreased significantly, displaying negative relationship with exposure time and dose. Chronic treatments with 0.1 mg/L or 1 mg/L nC 60 for 21 days significantly reduced survival and reproduction of D. magna. These harmful effects suggested negative impacts of nC 60 on aquatic ecosystems. Moreover, transcriptome analysis showed that the behavioural and chronic toxicity of nC 60 to D. magna might be related to physiological functions such as cell structural repair, protein degradation, energy metabolism and reproduction. We found that nC 60 accumulated in guts of D. magna, which should be responsible for the decrease of food ingestion and consequently inhibiting energy intake. Deficiency of energy not only affects behaviours but also declines reproduction in D. magna. Overall, this is the first study comprehensively considered the behavioral and chronic toxicity of nC 60 to aquatic organism. The results should be helpful to better understand the ecological consequences of C 60 released into water environments., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

It is greatly important to promote low-carbon green transformations in China, for implementing the emission reduction commitments and global climate governance. However, understanding the spatial spillover effects of carbon emissions will help the government achieve this goal. This paper selects the carbon-emission intensity panel data of 11 provinces in the Yangtze River Economic Belt from 2004 to 2016. Then, this paper uses the Global Moran's I to explore the spatial distribution characteristics and spatial correlation of carbon emission intensity. Furthermore, this paper constructs a spatial econometric model to empirically test the driving path and spillover effects of relevant factors. The results show that there is a significant positive correlation with the provincial carbon intensity in the Yangtze River Economic Belt, but this trend is weakening. The provinces of Jiangsu, Zhejiang, and Shanghai are High-High agglomerations, while the provinces of Yunnan and Guizhou are Low-Low agglomerations. Economic development, technological innovation, and foreign direct investion (FDI) have positive effects on the reduction of carbon emissions, while industrialization has a negative effect on it. There is also a significant positive spatial spillover effect of the industrialization level and technological innovation level. The spatial spillover effects of FDI and economic development on carbon emission intensity fail to pass a significance test. Therefore, it is necessary to promote cross-regional low-carbon development, accelerate the R&D of energy-saving and emission-reduction technologies, actively enhance the transformation and upgrade industrial structures, and optimize the opening up of the region and the patterns of industrial transfer.