Microplastics as an emerging menace to environment: Insights into their uptake, prevalence, fate, and sustainable solutions

Micro-nanoscale polystyrene co-exposure impacts the uptake and translocation of arsenic and boscalid by lettuce (Lactuca sativa)

The influence of micro-nanoplastics (MNPs) on the fate and effects of other pollutants present in the environment is largely unknown. This study evaluated if the root exposure to MNPs (polystyrene, PS; 20 or 1000 nm) had an impact on the accumulation of arsenic and boscalid (As and Bos) in lettuce (Lactuca sativa). Under hydroponic conditions, plants were co-exposed to MNPs at 10 or 50 mg/L, and to 1 mg/L of each environmental pollutant (EP). For soil-like media, plants were exposed to MNPs at 50 and EPs at 10 mg/kg. Phytotoxicity was enhanced by PS under both growth conditions, particularly by nanoscale PS (nPS), although impacts were less in potting mix-grown plants. Nanoscale PS had a greater impact than microscale PS (μPS) on As fate; the As translocation factor from roots to the edible shoots was increased 3-fold in plants exposed to nPS (50 mg/L) and EPs. PS dose and size had a variable impact on Bos uptake and translocation. Fluorescent microscopy analysis of lettuce co-exposed to MNPs and EPs suggests that nPS is entering the roots and translocating to the leaves, while μPS mostly remains in the roots. Pyrolysis-GC/MS showed that in solid media, the presence of EPs significantly increased the translocation of nPS to lettuce shoots from 4.43 ± 0.53 to 46.6 ± 9.7 mg/kg, while the concentration of μPS in the shoots remained the same regardless of the presence of EPs (ranging between 13.2 ± 5.5 to 14.2 ± 4.1 mg/kg). These findings demonstrate that co-exposure of MNPs with other EPs can significantly impact co-contaminant accumulation and toxicity, presenting an unknown risk to humans and other receptors.

Fungal microbiota of biodamages of various polymeric materials

Data on microbial fouling of various synthetic polymer materials, including those used in space technology, are summarized. It has been established that the dominant groups of microbiota of polymer fouling are the genera of mitosporous fungi Aspergillus, Penicillium, Alternaria, Trichoderma. The enzymatic properties of fungal strains from the collection of microbial cultures of the Microbial Depository Center of the National Academy of Sciences of Armenia were studied. It has been shown that Aspergillus fumigatus, Penicillium chrysogenum, P. steckii, Juxtiphoma eupyrena and a number of other fungi have biofouling activity towards polyethylene, polyethylene terephthalate and some other synthetic polymers. New fungal kits have been developed and proposed to evaluate the fungal resistance of polymeric materials. They include fungi isolated from bio-damaged polymers used in space technology and contain 2 to 5 fungal strains instead of 7 to 9 strains in previously used kits. Taking into account the obtained data, a comparative assessment of the fungal resistance of samples of synthetic polymeric materials of various classes that passed accelerated climatic tests has been carried out. It has been established that the kits of biodegradant fungi, composed of cultures of bio-damaged space technology, generally exceeded the activity of the previously used kits, based on which one can judge the obvious advantages of strains isolated from bio-damaged space technology. In the future, these kits could find application not only for biodegradation of polymers, but also for testing the biostability of various polymers, to use for the construction of aviation and space techniques. Moreover, new optimized kits may be developed based on the strains involved in this study.

Investigation of cell-to-cell transfer of polystyrene microplastics through extracellular vesicle-mediated communication

Plastics are an essential part of human life and their production is increasing every year. Plastics degrade into small particles (<5 mm, microplastics, MPs) in the environment due to various factors. MPs are widely distributed in the environment, and all living organisms are exposed to the effects of MPs. Extracellular vesicles (EVs) are small membrane particles surrounded by a lipid bilayer that are released into the environment by various cell types and are highly involved in inter- and intra-cellular communication through the exchange of proteins, nucleic acids, and lipids between cells. There have been numerous reports of adverse effects associated with the accumulation of MPs in human and animal cells, with recent studies showing that plastic treatment increases the number of EVs released from cells, but the mechanisms by which MPs accumulate and move between cells remain unclear. In this study, we investigated whether polystyrene (PS)-MPs are transferred cell-to-cell via EVs. This study showed that cell-derived EVs can transport plastic particles. Furthermore, we confirmed the accumulation of PS-MPs transported by EVs within cells using a real-time imaging device. This study provides an understanding of potential EVs-mediated effects of PS-MPs on organisms and suggests directions for further research.

Microplastics-biofilm interactions in biofilm-based wastewater treatment processes: A review

Microplastics, pervasive contaminants from plastic, present significant challenges to wastewater treatment processes. This review critically examines the interactions between microplastics and biofilm-based treatment technologies, specifically focusing on the concepts of "biofilm on microplastics" and "microplastics in biofilm". It discusses the implications of these interactions in contaminant removal and process performance. Advanced characterization techniques, including morphological characterization, chemical composition analysis, and bio-information analysis, are assessed to elucidate the complex interplay between microplastics and biofilms within biofilters, biological aerated filters (BAFs), rotating biological contactors (RBCs), and moving bed biofilm reactors (MBBRs). This review synthesizes current research findings, highlighting that microplastics can either hinder or enhance the treatment processes, contingent on their concentration, physicochemical properties, and the specific biofilm technology employed. The insights gained from this review are essential for developing strategies to mitigate the adverse effects of microplastics and for optimizing the design and operation of wastewater treatment.

Cobalt nanoparticles attenuate microplastic-induced vascular endothelial injury via Nrf2 pathway activation

The widespread utilization of plastic and cobalt alloy products in industries and medicine has led to the increased presence of their degradation byproducts, microplastics (MPs), and cobalt nanoparticles (Co NPs), in the environment and organisms. While these particles can circulate throughout the body via the circulatory system, their specific adverse effects and mechanisms on the vascular system remain unclear. Employing scanning electron microscope (SEM) analysis and other methodologies, we demonstrate the potential adsorption and aggregation phenomena between MPs and Co NPs. In vitro experiments illustrate that ingestion of either MPs or Co NPs compromises vascular endothelial cell function and induces the generation of reactive oxygen species (ROS). Notably, this effect is markedly attenuated when a combination of MPs and Co NPs is administered compared to MPs alone. Additionally, zebrafish experiments validate our in vitro findings. Mechanistic studies have demonstrated that both MPs and Co NPs induce aberrant Nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. Intriguingly, a weaker activation level is observed when these agents are administered in combination compared to when they are administered individually. Our study provides novel insights into the interaction between MPs and Co NPs and their detrimental effects on vascular endothelial cells.

Microplastics in riverine systems: Recommendations for standardized sampling, separation, digestion and characterization

Microplastic (MP) pollution has emerged as a global concern, prompting numerous studies on MP detection. Due to the remaining methodological challenges, it affects the accuracy and reliability of MP's impact assessment on river systems. To address this, the establishment of standardized operating protocols is crucial, encompassing sampling, separation, digestion, and characterization methods. This study evaluates the current tools used for identifying and quantifying MPs in riverine ecosystems, aiming to offer harmonized guidelines for future protocols. Recommendations include adopting a consistent format for reporting MP concentrations and providing improved information on sampling, separation, and digestion for enhanced cross-study comparisons. The importance of quality assurance and quality control is also discussed. Furthermore, we highlight unresolved issues, proposing avenues for further investigation. Suggestions encompass standardizing river sampling methods, optimizing technical steps and analysis processes, and enhancing the accuracy, reliability, and comparability of detection data to advance our understanding of MPs in river environments.

Overview of the environmental risks of microplastics and their controlled degradation from the perspective of free radicals

Owing to the significant environmental threat posed by microplastics (MPs) of varying properties, MPs research has garnered considerable attention in current academic discourse. Addressing MPs in river-lake water systems, existing studies have seldom systematically revealed the role of free radicals in the aging/degradation process of MPs. Hence, this review aims to first analyze the pollution distribution and environmental risks of MPs in river-lake water systems and to elaborate the crucial role of free radicals in them. After that, the study delves into the advancements in free radical-mediated degradation techniques for MPs, emphasizing the significance of both the generation and elimination of free radicals. Furthermore, a novel approach is proposed to precisely govern the controlled generation of free radicals for MPs' degradation by interfacial modification of the material structure. Hopefully, it will shed valuable insights for the effective control and reduction of MPs in river-lake water systems.

Occurrence, distribution and sources of microplastics in typical marine recirculating aquaculture system (RAS) in China: The critical role of RAS operating time and microfilter

Industrial mariculture, a vital means of providing high quality protein to humans, is a potential source of microplastics (MPs) which have recently received increasing attention. This study investigated the occurrence and distribution of microplastics in feed, source water and recirculating aquaculture system (RAS) with long & short operating times as well as in fish from typical industrial mariculture farms in China. Results showed that microplastics occurred in all samples with the average concentration of 3.53 ± 1.39 particles/g, 0.70 ± 0.17 particles/L, 1.53 ± 0.21 particles/L and 2.21 ± 0.62 particles/individual for feed, source water, RAS and fish, respectively. Microplastics were mainly fiber in shape, blue in color and 20-500 μm in size. Compared with short operated RAS, long operating time led to higher microplastic concentration in RAS, especially that of microplastic in 20-500 μm, granular and blue. Regardless of short or long operating time, microplastics in RAS mainly gathered in culture tank, tank before microfilter and fixed-bed biological filter, and the microfilter removed efficiently the microplastic with the shape of film, granule, fragment as well as those with size > 1000 μm. As for the polymer types, polyamide (PA, 71.9 %) and polyethylene terephthalate (PET, 65.7 %) dominated in feed and source water, respectively, which may be the reason for the high proportion of PA (38.8 % and 26.4 %) and PET (31.8 % and 30.2 %) in RAS and fish. In addition, polypropylene (PP) was also detected in RAS (18.7 %) and fish (22.6 %), indicating that other plastic facilities such as PP brush carrier also made a contribution. Positive matrix factorization (PMF) model revealed three sources of MP in RAS, namely plastic facilities, industrial sewage and plastic packaging products. Our results provided a theoretical basis for the management of MP in RAS.

Microplastic-induced NAFLD: Hepatoprotective effects of nanosized selenium

Polystyrene microplastics (MPs) are persistent environmental pollutants commonly encountered in daily human life. Numerous studies have demonstrated their ability to induce liver damage, including oxidative stress, inflammation, and lipid accumulation. However, limited information exists regarding preventive measures against this issue. In our study, we investigated the potential preventive role of selenium nanoparticles (YC-3-SeNPs) derived from Yak-derived Bacillus cereus, a novel nanobiomaterial known for its antioxidant properties and lipid metabolism regulation. Using transcriptomic and metabolomic analyses, we identified key genes and metabolites associated with oxidative stress and lipid metabolism imbalance induced by MPs. Upregulated genes (Scd1, Fasn, Irs2, and Lpin) and elevated levels of arachidonic and palmitic acid accumulation were observed in MP-exposed mice, but not in those exposed to SeNPs. Further experiments confirmed that SeNPs significantly attenuated liver lipid accumulation and degeneration caused by MPs. Histological results and pathway screening validated our findings, revealing that MPs suppressed the Pparα pathway and Nrf2 pathway, whereas SeNPs activated both pathways. These findings suggest that MPs may contribute to the development of nonalcoholic fatty liver disease (NAFLD), while SeNPs hold promise as a future nanobio-product for its prevention.

Microplastics as carriers of toxic pollutants: Source, transport, and toxicological effects

Microplastic pollution has emerged as a new environmental concern due to our reliance on plastic. Recent years have seen an upward trend in scholarly interest in the topic of microplastics carrying contaminants; however, the available review studies have largely focused on specific aspects of this issue, such as sorption, transport, and toxicological effects. Consequently, this review synthesizes the state-of-the-art knowledge on these topics by presenting key findings to guide better policy action toward microplastic management. Microplastics have been reported to absorb pollutants such as persistent organic pollutants, heavy metals, and antibiotics, leading to their bioaccumulation in marine and terrestrial ecosystems. Hydrophobic interactions are found to be the predominant sorption mechanism, especially for organic pollutants, although electrostatic forces, van der Waals forces, hydrogen bonding, and pi-pi interactions are also noteworthy. This review reveals that physicochemical properties of microplastics, such as size, structure, and functional groups, and environmental compartment properties, such as pH, temperature, and salinity, influence the sorption of pollutants by microplastic. It has been found that microplastics influence the growth and metabolism of organisms. Inadequate methods for collection and analysis of environmental samples, lack of replication of real-world settings in laboratories, and a lack of understanding of the sorption mechanism and toxicity of microplastics impede current microplastic research. Therefore, future research should focus on filling in these knowledge gaps.

Effect of plastic mulch residue on plant growth performance and soil properties

Plastic mulch is widely utilized for weed control, temperature regulation, soil erosion prevention, disease management, and soil structure improvement, ultimately enhancing crop quality and yield. However, a significant issue with conventional plastic mulches is their low recycling rates, which can cause plastic residue to build up, thereby damaging soil quality and reducing crop yield. The emergence of biodegradable films offers a promising solution to mitigate this issue and reduce soil pollution. However, its potential effects on soil properties and plant performance remain unclear. In this study, low-density polyethylene (LDPE) and poly (butylene succinate-co-butylene adipate) (PBSA) were used to observe the effect of plastic mulch residues on soil properties and plant growth performance via potting experiment. Additionally, the interaction effects of compost and biochar as soil amendments with plastic mulch residues were also evaluated. The result of this study revealed that the type of plastic significantly affected the total nitrogen and magnesium uptake; however, the morphological traits of the tested plant (Japanese mustard spinach) were not significantly affected. The addition of compost and biochar led to a significant increase in both shoot and total dry weight of the plant, indicating a positive effect on its growth. The results of the two-way ANOVA indicated a significant influence of plastic type on dissolved phosphate (PO43-) levels and soil dehydrogenase activity (DHA). The interaction effect (plastic type with soil amendment) was statistically significant only for soil DHA. Neither plastic mulch residues nor soil amendments significantly affected other soil chemical properties. However, long-term experiments to systematically investigate the long-term effects of plastic residues are necessary.

Environmental pollutants induce NLRP3 inflammasome activation and pyroptosis: Roles and mechanisms in various diseases

Environmental pollution is changing with economic development. Most environmental pollutants are characterized by stable chemical properties, strong migration, potential toxicity, and multiple exposure routes. Harmful substances are discharged excessively, and large quantities of unknown new compounds are emerging, being transmitted and amplifying in the food chain. The increasingly severe problems of environmental pollution have forced people to re-examine the relationship between environmental pollution and health. Pyroptosis and activation of the NLRP3 inflammasome are critical in maintaining the immune balance and regulating the inflammatory process. Numerous diseases caused by environmental pollutants are closely related to NLRP3 inflammasome activation and pyroptosis. We intend to systematically explain the steps and important events that are common in life but easily overlooked by which environmental pollutants activate the NLRP3 inflammasome and pyroptosis pathways. This comprehensive review also discusses the interaction network between environmental pollutants, the NLRP3 inflammasome, pyroptosis, and diseases. Thus, research progress on the impact of decreasing oxidative stress levels to inhibit the NLRP3 inflammasome and pyroptosis, thereby repairing homeostasis and reshaping health, is systematically examined. This review aims to deepen the understanding of the impact of environmental pollutants on life and health and provide a theoretical basis and potential programs for the development of corresponding treatment strategies.

A review of the effects of environmental hazards on humans, their remediation for sustainable development, and risk assessment

In the race for economic development and prosperity, our earth is becoming more polluted with each passing day. Technological advances in agriculture and rapid industrialization have drastically polluted the two pillars of natural resources, land and water. Toxic chemicals and microbial contaminants/agents created by natural and anthropogenic activities are rapidly becoming environmental hazards (EH) with increased potential to affect the natural environment and human health. This review has attempted to describe the various agents (chemical, biological, and physical) responsible for environmental contamination, remediation methods, and risk assessment techniques (RA). The main focus is on finding ways to mitigate the harmful effects of EHs through the simultaneous application of remediation methods and RA for sustainable development. It is recommended to apply the combination of different remediation methods using RA techniques to promote recycling and reuse of different resources for sustainable development. The report advocates for the development of site-specific, farmer-driven, sequential, and plant-based remediation strategies along with policy support for effective decontamination. This review also focuses on the fact that the lack of knowledge about environmental health is directly related to public health risks and, therefore, focuses on promoting awareness of effective ways to reduce anthropological burden and pollution and on providing valuable data that can be used in environmental monitoring assessments and lead to sustainable development.