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Micro- and nanoplastics (MNPs), emerging as pervasive environmental pollutants, present multifaceted threats to diverse ecosystems. This review critically examines the ability of MNPs to traverse biological barriers in fish, leading to their accumulation in gonadal tissues and subsequent reproductive toxicity. A focal concern is the potential transgenerational harm, where offspring not directly exposed to MNPs exhibit toxic effects. Characterized by extensive specific surface areas and marked surface hydrophobicity, MNPs readily adsorb and concentrate other environmental contaminants, potentially intensifying reproductive and transgenerational toxicity. This comprehensive analysis aims to provide profound insights into the repercussions of MNPs on fish reproductive health and progeny, highlighting the intricate interplay between MNPs and other pollutants. We delve into the mechanisms of MNPs-induced reproductive toxicity, including gonadal histopathologic alterations, oxidative stress, and disruptions in the hypothalamic-pituitary–gonadal axis. The review also underscores the urgency for future research to explore the size-specific toxic dynamics of MNPs and the long-term implications of chronic exposure. Understanding these aspects is crucial for assessing the ecological risks posed by MNPs and formulating strategies to safeguard aquatic life.

Ball milling, as a cost-effective and eco-friendly approach, has been popular in materials synthesis to solve problems involving toxic reagents, high temperatures, or high pressure, which has the potential for large-scale production. However, there are few reviews specifically concentrating on the latest progress in materials characteristics before and after ball milling as well as the adsorptive application for aqueous pollutants. Hence, this paper summarized the principle and classification of ball milling and reviewed the advances of mechanochemical materials in categories as well as their adsorption performance of organic and inorganic pollutants. Ball milling has the capacity to change materials’ crystal structure, specific surface areas, pore volumes, and particle sizes and even promote grafting reactions to obtain functional groups to surfaces. This improved the adsorption amount, changed the equilibrium time, and strengthened the adsorption force for contaminants. Most studies showed that the Langmuir model and pseudo-second-order model fitted experimental data well. The regeneration methods include ball milling and thermal and solvent methods. The potential future developments in this field were also proposed. This work tries to review the latest advances in ball-milled materials and their application for pollutant adsorption and provides a comprehensive understanding of the physicochemical properties of materials before and after ball milling, as well as their effects on pollutants’ adsorption behavior. This is conducive to laying a foundation for further research on water decontamination by ball-milled materials.

China’s sewage treatment standards have been gradually improving, yet there is a widening gap between sewage treatment fees and actual costs. This discrepancy, where the fees for sewage treatment are lower than the actual operational expenses, poses a significant bottleneck to the sustainable development of China’s sewage treatment industry. As a core aspect of environmental economic policies, sewage treatment fees are pivotal in regulating water pollution emissions and addressing water resource shortages. Currently, there are major issues with sewage treatment fees, including an incomplete pricing system, insufficient fees, unclear fee distribution, and a heavy reliance on local finances. These problems impede systematic planning, diminish management efficiency, and hinder the sustainable development of the sewage treatment industry. Thus, future research efforts should prioritize the establishment of a pricing mechanism that comprehensively covers the full cost of sewage treatment. This article presents a concise summary and review of the current situation, types of fee collection, cost accounting methodologies, challenges, and proposed countermeasures for sewage treatment fees, and could serve as a relevant reference for future research on sewage treatment fees. By comprehensively addressing these issues, the sewage treatment industry would progress towards healthier and more sustainable development, ultimately achieving the goal of green growth.

Harmful cyanobacterial blooms pose a major threat. Among them, Microcystis aeruginosa has raised serious concerns for human health due to its frequent occurrence. In this study, an ecological floating-bed system consisting of activated carbon fibers, aquatic plants (Ipomoea aquatica Forsskal), animals (Daphnia), and a solar-powered ultrasonic device was designed. The algae-killing efficiency, removal mechanism, and toxicological effects of the floating-bed system on Microcystis aeruginosa were determined under different conditions. The results showed that the average activity of algal cell dehydrogenase (DHA) was reduced by 64.09%, the average malondialdehyde (MDA) content was reduced to 0.125 μmol/L, and the average removal rate of soluble protein was 57.22% under optimal conditions (pH = 7, temperature = 25 °C, dissolved oxygen concentration = 5 mg/L, and hydraulic retention time = 36 h). Scanning electron microscopy (SEM) analysis showed that the structure within the cells of Microcystis aeruginosa was severely damaged after treatment with the solar-powered ultrasonic carbon fiber eco-floating-bed system. Fourier transform infrared (FTIR) spectroscopy analysis showed that the pyrrole ring of chlorophyll-a was degraded. In addition, a tadpole-based micronucleus test and a comet assay were conducted to assess cell viability and DNA damage in water samples treated with the floating-bed system, and the results confirmed that chromosome damage and genotoxicity were significantly reduced. These findings suggest that the floating-bed system is effective in destroying algal cells, leading to massive algal cell death and reducing the risk of secondary contamination. This study provides a new perspective for further research on ecological floating-bed technology, demonstrating its potential practical application in the prevention and control of cyanobacterial blooms.

Peroxymonosulfate (PMS) activation has gained increasing attention for its water remediation. In this work, carbon nanotube-supported FeCo2O4 nanoparticles (FeCo2O4/CNT) were prepared and showed tremendous potential as a catalyst for PMS activation. The synergistic effect between FeCo2O4 and CNT in FeCo2O4/CNT promotes its better catalytic performance than individual CNT or FeCo2O4. The synthesized FeCo2O4/CNT could reach 100% phenol removal with a k value of 0.30 min−1 within 15 min ([PMS] = 0.3 g L−1, [FeCo2O4/CNT] = 0.3 g L−1). FeCo2O4/CNT can adapt well to a wide pH range (4–9) and a complex water component (with inorganic ions or organic matter). Moreover, the catalytic mechanism investigation suggested that both radical and non-radical pathways are accountable for the efficient removal of phenol.

Soil pollution is a global environmental problem. Nanoscale zero-valent iron (nZVI) as a kind of emerging remedial material is used for contaminated soil, which can quickly and effectively degrade and remove pollutants such as organic halides, nitrates and heavy metals in soil, respectively. However, nZVI and its composites can enter the soil environment in the application process, affect the physical and chemical properties of the soil, be absorbed by microorganisms and affect the growth and metabolism of microorganisms, thus affecting the ecological environment of the entire soil. Because of the potential risks of nZVI to the environment and ecosystems, this paper summarizes the current application of nZVI in the remediation of contaminated soil environments, summarizes the various factors affecting the toxic effects of nZVI particles and comprehensively analyzes the toxic effects of nZVI on microorganisms, toxic mechanisms and cell defense behaviors to provide a theoretical reference for subsequent biosafety research on nZVI.

In recent years, the frequent outbreaks of cyanobacterial blooms have caused severe water pollution in many rivers and lakes at home and abroad, endangering drinking water safety and human health. How to remove cyanobacteria from water bodies safely, quickly, and economically has attracted the attention of many scientists. Currently, the typical treatment methods for algae in algae-bearing water bodies are physical, biological, and chemical methods. The physical method of algae removal is for both the symptoms and the root cause, but the workload is extensive, with high input costs, and should not be used on a large scale. The biological method is low-cost, but the removal efficiency is slow and unsuitable for the treatment of sudden water bloom. The chemical method can kill algae quickly, but it is easy to cause secondary pollution. These methods are relatively independent of each other, so the choice of a practical combination of technologies is essential for algal bloom removal and eutrophication management. This paper reviews the current application status and advantages and disadvantages of algae removal technologies at home and abroad; classifies them from physical, chemical, biological, and combined methods; and provides an outlook on the future development direction of algae removal technologies.

This study mainly investigated the adsorption behavior and mechanism of microfiltration membranes (MFMs) with different physiochemical properties (polyamide (PA), polyvinylidene fluoride (PVDF), nitrocellulose (NC), and polytetrafluoroethylene (PTFE)) for bisphenol A (BPA). According to the adsorption isotherm and kinetic, the maximum adsorption capacity of these MFMs was PA (161.29 mg/g) > PVDF (80.00 mg/g) > NC (18.02 mg/g) > PTFE (1.56 mg/g), and the adsorption rate was PVDF (K1 = 2.373 h−1) > PA (K1 = 1.739 h−1) > NC (K1 = 1.086 h−1). The site energy distribution analysis showed that PA MFMs had the greatest adsorption sites, followed by PVDF and NC MFMs. The study of the adsorption mechanism suggested that the hydrophilic microdomain and hydrophobic microdomain had a micro-separation for PA and PVDF, which resulted in a higher adsorption capacity of PA and PVDF MFMs. The hydrophilic microdomain providing hydrogen bonding sites and the hydrophobic microdomain providing hydrophobic interaction, play a synergetic role in improving the BPA adsorption. Due to the hydrogen bonding force being greater than the hydrophobic force, more hydrogen bonding sites on the hydrophobic surface resulted in a higher adsorption capacity, but the hydrophobic interaction contributed to improving the adsorption rate. Therefore, the distribution of the hydrophilic microdomain and hydrophobic microdomain on MFMs can influence the adsorption capacity and the adsorption rate for BPA or its analogues. These consequences provide a novel insight for better understanding the adsorption behavior and mechanism on MFMs.

As a new type of polymer, water-driven polyurethane (PU) has attracted increasing attention of researchers; however, with the popularization of its application, the following infection problems limit their applications, especially in the biomedical field. Herein, a series of novel cellulose nanocrystals (CNCs)-based PUs were first synthesized by chemical cross-linking CNCs with triblock copolymer polylactide–poly (ethylene glycol)–polylactide (CNC-PU). After covalent binding with tannic acid (TA-CNC-PU), the silver nanoparticles (Ag NPs) were further introduced into the material by a reduction reaction (Ag/TA-CNC-PU). Finally, the prepared serial CNCs-based PU nanocomposites were fully characterized, including the microstructure, water contact angle, water uptake, thermal properties as well as antibacterial activity. Compared with CNC-PU, the obtained TA-CNC-PU and Ag/TA-CNC-PU were capable of lower glass transition temperatures and improved thermal stability. In addition, we found that the introduction of tannic acid and Ag NPs clearly increased the material hydrophobicity and antibacterial activity. In particular, the Ag/TA-CNC-PU had a better antibacterial effect on E. coli, while TA-CNC-PU had better inhibitory effect on S. aureus over a 24 h time period. Therefore, these novel CNCs-based PUs may be more beneficial for thermal processing and could potentially be developed into a new class of smart biomaterial material with good antibacterial properties by adjusting the ratio of TA or Ag NPs in their structures.

Biogenic manganese oxides (Bio-MnOx) have attracted considerable attention for removing pharmaceutical contaminants (PhCs) due to their high oxidation capacity and environmental friendliness. Mn-oxidizing microalgae (MnOMs) generate Bio-MnOx with low energy and organic nutrients input and degrade PhCs. The combined process of MnOMs and Bio-MnOx exhibits good prospects for PhCs removal. However, the synergistic effects of MnOMs and Bio-MnOx in PhCs removal are still unclear. The performance of MnOMs/Bio-MnOx towards diclofenac (DCF) removal was evaluated, and the mechanism was revealed. Our results showed that the Bio-MnOx produced by MnOMs were amorphous nanoparticles, and these MnOMs have a good Mn2+ tolerance and oxidation efficiency (80–90%) when the Mn2+ concentration is below 1.00 mmol/L. MnOMs/Bio-MnOx significantly promotes DCF (1 mg/L) removal rate between 0.167 ± 0.008 mg/L·d (by MnOMs alone) and 0.125 ± 0.024 mg/L·d (by Bio-MnOx alone) to 0.250 ± 0.016 mg/L·d. The superior performance of MnOMs/Bio-MnOx could be attributed to the continuous Bio-MnOx regeneration and the sharing of DCF degradation intermediates between Bio-MnOx and MnOMs. Additionally, the pathways of DCF degradation by Bio-MnOx and MnOMs were proposed. This work could shed light on the synergistic effects of MnOMs and Bio-MnOx in PhCs removal and guide the development of MnOMs/Bio-MnOx processes for removing DCF or other PhCs from wastewater.

At present, there are few studies on known bacterial species and even less on fungi in biological algae control technology. In this paper, the green eutrophic shallow water lake Scenedesmus quadricauda (Turpin) was used as the research object, and white rot fungi, which has a high removal effect on water pollutants, algae and biological toxins, was used for algae control. The extent of the removal effect, physiological characteristics and the internal functional groups of the algae cells in the white rot fungi solution, the supernatant of the white rot fungi solution after centrifugation and the sterilized white rot fungi solution were investigated. The results showed that the best algae solubilization effect of the algae control system was achieved at 250 mg/L, with 8 mg/L of dissolved oxygen and a hydraulic retention time of 48 h. The average algae lysis rate was 85.48%, the average dehydrogenase activity reduction rate was 59.23%, the average soluble protein reduction rate was 65.16% and the average malondialdehyde content increased to 0.128 umol/L. After treatment with the white rot algae control system, the spatial structure of the Turpin cells was severely disrupted, and significant lysis occurred within the algal cells, forcing the release of intracellularly soluble substances, and reducing the dehydrogenase activity of the Turpin cells, thus inhibiting the growth activity of the algae cells. A further reduction in the soluble protein content reduces the nutrients required for the growth of Turpin, exacerbating the rate of reduction in the physiological metabolic activity of the Turpin cells and, ultimately, the inhibition or killing of the algal cells. The results of this research may provide theoretical guidance for the microbial control of water eutrophication; however, whether there will be secondary pollution after the algae dissolution of this process is worthy of further study.

Current research on the inhibition of Microcystis aeruginosa growth is primarily focused on algae-lysing bacteria, and few studies have investigated the inhibitory mechanisms by which fungi affect it at the molecular level. A comparative analysis of the effects of Phanerochaete chrysosporium on the expression of the algal cell antioxidant protease synthesis gene prx, the biological macromolecule damage and repair genes recA, grpE, and fabZ, and the photosynthesis system-related genes psaB, psbD1 and rbcL, as well as genes for algal toxin synthesis mcyB, were performed to elucidate the molecular mechanism of Phanerochaete chrysosporium against Microcystis aeruginosa cells. RT-qPCR technology was used to study the molecular mechanism of algal cell inhibition by Phanerochaete chrysosporium liquid containing metabolites of Phanerochaete chrysosporium, Phanerochaete chrysosporium supernatant and Phanerochaete chrysosporium inactivated via high temperature sterilization at the gene expression level. Compared with the control, the chlorophyll-a contents dropped, and the recA, grpE, fabZ, and prx increased, but the psaB, psbD1, rbcL and mcyB showed that they were significantly reduced, which indicated that Phanerochaete chrysosporium can not only effectively destroy algal cells, but they may also reduce the expression of the Microcystis aeruginosa toxin gene and significantly block the metabolic system underlying the growth of algal cells and the synthesis of microcystins.

Poly(lactic acid) has been extensively investigated in the biomedical field because of its good biocompatibility and biodegradability. As an important method of poly(lactic acid) synthesis, metal complex-catalyzed ring-opening polymerization (ROP) of lactide can achieve a controllable lactide polymerization through the selection of appropriate ligands and metals. In this study, a novel metal (LTi-O)2 complex was synthesized and structurally characterized. (LTi-O)2 showed a relatively high catalytic activity and controllability of Poly(D, L-lactide) (PDLLA) molecular weights (polydispersity index of 1.02-1.22) in the ROP of D,L-lactide. The kinetic equation of D,L-LA ROP catalyzed by (LTi-O)2 could be expressed as-d[M]/dt = k[M]2[(LTi-O)2]1, and the reaction activation energy was 95.67 kJ·mol-1. Physical/chemical properties and biocompatibility evaluation results showed that PDLLA obtained through the (LTi-O)2-catalyzed ROP of D,L- lactide exhibited a good degradation performance and excellent biocompatibility.

Cyanobacterial blooms constituted a serious threat to water environments around the world, and a series of ecological chain reactions accompany them. Because algae have strong reproduction speed and adaptability, it is very difficult for people to address the conundrum of algae-containing water. Common algae removal methods include physical, chemical and biological methods. Compared to these techniques, nZVI has many advantages such as low cost and high efficiency. Yet, there is still a lack of research on the application of nZVI to remove cyanobacterial blooms. Consequently, in this review, recent research on the use of nZVI for environmental governance is analyzed. By analyzing the nZVI material properties, applications and modification aspects. We propose to use BC made from cyanobacteria as a support carrier for nZVI to enhance the algae control system BC/nZVI with a synthetic composite base nZVI system, and highlight the performance advantages of BC loaded with nZVI. On the one hand, BC can provide more attachment sites for nZVI to improve nZVI dispersion and reduce agglomeration, thus improving the stability of this algae control system; on the other hand, nZVI not only has certain removal effect on algae, but also can effectively degrade various pollutants adsorbed on BC, improve the regenerability of BC and prolong its service life, thus enhancing the efficiency and sustainability of this algae control system. This enhances the efficiency and sustainability of the algae control system. This review can provide a new approach for the management of cyanobacterial blooms and the secondary utilization of algal biomass. [ABSTRACT FROM AUTHOR]

nZVI is an advanced water treatment material discovered in recent years, which has the characteristics of efficient degradation of organic pollutants, low cost and no secondary pollution, so it is a promising environmentally friendly material. However, nZVI is easily oxidized and agglomerated, which seriously affects its water treatment effect. It has been found that the stability and safety of nZVI can be effectively improved by loading nZVI into other materials for water treatment. This paper mainly introduces the action principle and preparation method of nZVI and the action principle of nZVI modified materials in water treatment, and expounds the research progress of nZVI loaded composites in water treatment, which can provide technical guidance for the application of nZVI in water treatment. [ABSTRACT FROM AUTHOR]

Despite low exposure level in the water, environmental hormone pollutants can still inflict significant biological effects that endanger ecological safety and human reproduction. However, they are unable to be effectively removed using ordinary water treatment methods, which makes the deposition of environmental residues highly likely. In light of this demand, this study synthesized metal-doped g-C3N4 composite photocatalysts and coupled them with nitrogen doped ordered mesoporous (NMC) carbon to treat water contaminated by environmental hormone micropollutants. The experimental results show that AgIn5S8/g-C3N4 (25%) makes the prime candidate for degrading bisphenol A (BPA), displaying the highest degradation rates of 82%. Moreover, h+ and·O2- were found to be the main active substances in the photocatalytic process, while the degradation rate of BPA by AgIn5S8/g-C3N4 (25%) was still over 80% after 5 repeated photocatalyses. When the nitrogen doped ordered mesoporous carbon was coupled with AgIn5S8/g-C3N4 (25%), the degradation and removal rates of BPA were greatly improved, demonstrating up to 94.8% removal rate in batch treatment. Furthermore, NMC/AgIn5S8/g-C3N4 also exhibited good adsorption-photocatalytic synergy under continuous flow conditions of the fluidized bed, and the highest removal rate of BPA in the dark-free adsorption experiment was about 98.1%. [ABSTRACT FROM AUTHOR]

Pectin was extracted from tobacco stems using an HCl-CH3COOH mixed acid extraction method to assess as a potential tool in commercial pectin production. The effect of hot and cold pretreatments on the pectin yield was investigated first. Then, the response surface methodology was used to determine the effects of the solid-liquid ratio (1/20-1 /40), extraction temperature (80-100 °C) and time (90-150 min) on the pectin yield, and the maximum extraction yield appeared at 88.8 °C, 128 min and a solid-liquid ratio of 1/34. Lastly, the pectins obtained from the mixed acid and single acid treatments were analyzed and compared by yield, structure and physicochemical properties. According to the results, it can be concluded that the mixed HC1-CH3COOH acid could combine the yield and esterification degree of strong inorganic acid and organic acid and yield pectin products with ideal physicochemical properties. [ABSTRACT FROM AUTHOR]

The mechanism of lignin degradation via white rot fungi was studied. Phanerochaete chrysosporium and Pleurotus ostreatus were used for all the experiments, i.e., measuring the concentration and structure of alkali lignins and studying the effect of the substrate concentration and enzyme activity on the removal. Gas chromatography-mass spectrometry was performed on the reaction liquid of the lignin degradation enzyme system. Alkali lignin had a characteristic absorption spectrum with a peak at approximately 280 nm. Precipitation in the laccase (Lac) degradation system occurred earlier, as well as being more obvious than that in the manganese peroxidase (Mnp) degradation system. The maximum removal was 29.4% in the Mnp degradation system at a concentration of 40 mg/L. The removal increased in a concentration-dependent manner in the Lac degradation system. The increase in Mnp and Lac enzyme activity led to an increased alkali lignin removal. The removal of the control group was significantly lower than the experimental degradation systems. The degradation mainly produced organic acids, esters, and aromatic substances. In conclusion, white rot fungi could effectively remove alkali lignin, in which precipitation played a major role, followed by enzymolysis; the enzymolysis was associated with the alkali lignin concentration and enzyme activity. [ABSTRACT FROM AUTHOR]

Eutrophication and frequent algal blooms have become serious ecological problems. White-rot fungi have been considered as possible microorganisms for controlling algal blooms. In this study, Cryptomonas obovata FACID3-1301, Oscillatoria sp. FACIIB-1083, and Scenedesmus quadncauda FACIIB-507 co-cultured with the white-rot fungus Phanerochaete chrysosporium. All algal cells were damaged within 48 h of coculture. P. chrysosporium apparently decreased the chlorophyll-a content, dehydrogenase activity, and soluble protein content but increased the malondialdehyde content of the algal cells. These results indicate that the algae were greatly inhibited and severely damaged by the fungus. In conclusion, P. chrysosporium can effectively remove algal cells and inhibit algal blooms. [ABSTRACT FROM AUTHOR]

It is important to inhibit Algal blooms by efficacy methods, which is caused water stench and threaten human health seriously. The strain of white-rot fungus may be one of the bio-treatment ways to do this, in particular, the Phanerochaete chryso-sporim. Its algicidal ability on algae was studied by three main influence factors: white rot fungus dosage, pi I value and DO. The results showed that the chlorophyll-a content of eutrophication water decreased 92.24% within 24 h under the optimum conditions that 250 mg/L at pH 7.0 for 7.0 mg/L. Pre-treated eutrophication water was investigated by algal cells dehydrogenase activity, soluble protein content and malondialdehyde. It was seen that decrease in algal cells dehydrogenase activity and soluble protein content and an increase in MDA con-lent, which were associated with the decrease in chlorophyll-a content. These results indicated that the fungus could destroy the algal cell and inhibit the algae blooms. [ABSTRACT FROM AUTHOR]

Lignocellulose is a renewable biomass resource, widely used in the fermentation. A reasonable pretreatment method is the key to reducing production costs and promoting the efficient transformation of lignocellulose. In this paper, the uniform design method was used to optimize the corn straw using aluminum trichloride, and the components and the structure of corn straw were analyzed. The optimum treatment conditions were as follows: the concentration of aluminum trichloride was 0.3 mol/L, the reaction temperature was 170 °C, the reaction time was 30 minutes, and the ratio of liquid to solid was 15:1 mL/g. Under these optimal conditions, the enzymatic hydrolysis results showed that the yield of the reducing sugar was 46.6%, which was higher than that of corn straw without pretreatment. The non-stereoregular material content decreased significantly, and the relative content of cellulose increased by 7.95%. X-ray diffraction (XRD) and scanning electron microscopy (SEM) results showed that the spatial structure of the straw was destroyed and the relative crystallinity of the cellulose decreased. After pretreatment, Fourier transform infrared spectroscopy (FTIR) results demonstrated that the functional groups had undergone significant changes, and the hydrogen bonds were destroyed, which is favorable for the molecular adsorption of cellulase. [ABSTRACT FROM AUTHOR]