Application of FTIR two-dimensional correlation spectroscopy (2D-COS) analysis in characterizing environmental behaviors of microplastics: A systematic review.

Microplastics (MPs) are ubiquitous in the environment, continuously undergo aging processes and release toxic chemical substances. Understanding the environmental behaviors of MPs is critical to accurately evaluate their long-term ecological risk. Generalized two-dimensional correlation spectroscopy (2D-COS) is a powerful tool for MPs studies, which can dig more comprehensive information hiding in the conventional one-dimensional spectra, such as infrared (IR) and Raman spectra. The recent applications of 2D-COS in analyzing the behaviors and fates of MPs in the environment, including their aging processes, and interactions with natural organic matter (NOM) or other chemical substances, were summarized systematically. The main requirements and limitations of current approaches for exploring these processes are discussed, and the corresponding strategies to address these limitations and drawbacks are proposed as well. Finally, new trends of 2D-COS are prospected for analyzing the properties and behaviors of MPs in both natural and artificial environmental processes.

Physicochemical characteristics of airborne microplastics of a typical coastal city in the Yangtze River Delta Region, China.

Airborne microplastics (MPs) are important pollutants that have been present in the environment for many years and are characterized by their universality, persistence, and potential toxicity. This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime. Laser direct infrared imaging (LDIR) and polarized light microscopy were used to characterize the physical and chemical properties of MPs, including number concentration, chemical types, shape, and size. Backward trajectories were used to distinguish the air masses from marine and terrestrial transport. Twenty chemical types were detected by LDIR, with rubber (16.7%) and phenol-formaldehyde resin (PFR; 14.8%) being major components. Three main morphological types of MPs were identified, and fragments (78.1%) are the dominant type. MPs in the atmosphere were concentrated in the small particle size segment (20-50 µm). The concentration of MPs in the air mass from marine transport was 14.7 items/m3 - lower than that from terrestrial transport (32.0 items/m3). The number concentration of airborne MPs was negatively correlated with relative humidity. MPs from terrestrial transport were mainly rubber (20.2%), while those from marine transport were mainly PFR (18%). MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass. The number concentration of airborne MPs is higher during the day than at night. These findings could contribute to the development of targeted control measures and methods to reduce MP pollution.

Real-Time Detection of Microplastics Using an AI Camera.

Microplastics (MPs, size ≤ 5 mm) have emerged as a significant worldwide concern, threatening marine and freshwater ecosystems, and the lack of MP detection technologies is notable. The main goal of this research is the development of a camera sensor for the detection of MPs and measuring their size and velocity while in motion. This study introduces a novel methodology involving computer vision and artificial intelligence (AI) for the detection of MPs. Three different camera systems, including fixed-focus 2D and autofocus (2D and 3D), were implemented and compared. A YOLOv5-based object detection model was used to detect MPs in the captured image. DeepSORT was then implemented for tracking MPs through consecutive images. In real-time testing in a laboratory flume setting, the precision in MP counting was found to be 97%, and during field testing in a local river, the precision was 96%. This study provides foundational insights into utilizing AI for detecting MPs in different environmental settings, contributing to more effective efforts and strategies for managing and mitigating MP pollution.

Proposed validation stages for MPs extraction from edible mussels (Mytilus galloprovincialis).

The potential presence of microplastics (MPs) in seafood products presents significant health concerns, demanding the adoption of standardized and validated methodologies. In this study, we introduce a validated method and an innovative technique for extracting MPs from mussels using an oxidizing agent, Corolase enzyme, and a surfactant, thus eliminating the need for mechanical agitation. Evaluation of the extraction process focused on three critical parameters: recovery percentage, repeatability, and chemical integrity, along with color stability. To ensure precision and reliability, low-density infrared spectroscopy (LDIR) was employed to analyze the effect of spectrum quality (Q). Ultimately, this methodology was applied to identify MPs in commercial mussels, with results showcasing the viability of the proposed validation stages for MPs extraction, maintaining MPs integrity with high recovery percentages.

[Response of Relationship Between Microplastic Abundance and Nitrogen Metabolism Function Microorganisms and Genes in Water].

The impact of microplastics (MPs) as a new type of pollutant on water pollution has become a research hotspot. To explore the response relationship between the abundance of MPs and nitrogen metabolism function in a freshwater environment, Lake Ulansuhai was used as the research object; the abundance of MPs in the water was detected using a Zeiss microscope, and the distribution characteristics of nitrogen metabolism functional bacteria and functional genes in the water were analyzed using metagenomics sequencing. The correlation analysis method was used to explore the relationship between the abundance of MPs and nitrogen metabolism functional microorganisms and nitrogen metabolism functional genes. The results showed that the presence of MPs in freshwater environments had a higher impact on Cyanobacteria and Firmicutes as the dominant phyla, and the presence of MPs promoted their enrichment and growth. Among the dominant bacterial genera, MPs promoted the growth of Mycobacterium and inhibited Candidatus_Planktopila more significantly, further indicating that in freshwater environments, MPs affected normal nitrogen metabolism by affecting microbial communities, and pathways such as carbon and nitrogen fixation and denitrification were important pathways for MPs to affect nitrogen metabolism. From the perspective of nitrogen metabolism functional genes, it was found that the abundance of MPs significantly affected some functional genes during nitrification (pmoA-amoA, pmoB-amoB, and pmoC-amoC), denitrification (nirK and napA), and dissimilatory nitrate reduction (nrfA) processes (P < 0.05). Moreover, the influence of MPs abundance on different functional genes in the same pathway of nitrogen metabolism varied, making the impact of MPs on aquatic environments very complex; thus, its harm to the water environment cannot be underestimated.

[Effects and Mechanisms of Polystyrene Microplastics on Extracellular Antibiotic Resistance Genes in Wastewater].

Microplastics (MPs) and antibiotic resistance genes (ARGs) are typical co-existing emerging pollutants in wastewater treatment plants. MPs have been shown to alter the distribution pattern of ARGs in sludge, but their effects on free extracellular ARGs (feARGs) in wastewater remain unclear. In this study, we used fluorescence quantitative PCR to investigate the dynamics of feARGs (including tetC, tetO, sul1, and sul2) in wastewater and their transition mechanisms after 60 d of exposure to typical MPs (polystyrene, PS). The results showed that the absolute abundance of tetracycline feARGs decreased by 28.4 %-76.0 % and 35.2 %-96.2 %, respectively, under nm-level and mm-level PS exposure and changed by -55.4 %-122.4 % under µm-level PS exposure. The abundance of sul1 showed a trend of nm-level > µm-level > mm-level upon PS exposure, and the changes in sul1 abundance was greater with ρ(PS)=50 mg·L-1 exposure. The relative abundance of sul2 was reduced by 25.4 %-42.6 % and 46.1 %-90.3 % after µm-level and mm-level PS exposure, respectively, and increased by 1.9-3.9 times after nm-level PS exposure, and the sul2 showed a higher reduction at ρ (PS)=50 mg·L-1 exposure than that at ρ (PS)=0.5 mg·L-1. The Pearson correlation analysis showed that the relative abundance of feARGs during PS exposure was positively correlated with cell membrane permeability and typical mobile genetic elements (intI1) abundance and negatively correlated with reactive oxygen species level. Our findings elucidated the effects and corresponding mechanisms of PS on the growth and mobility of feARGs in wastewater, providing a scientific basis for the control of the combined MPs and ARGs pollution in wastewater.

[Effect of Low-density Polyethylene Microplastics on Natural Attenuation of Oxygenated Polycyclic Aromatic Hydrocarbons in Soil].

The continuous accumulation of microplastics in agricultural soils may affect the natural attenuation of oxygen-containing polycyclic aromatic hydrocarbons (OPAHs). The effects of low-density polyethylene (LDPE) microplastics with the spiking proportion of 1 % and 0.01 % in soils on the natural attenuation of OPAHs were investigated via soil microcosm experiments. The relation between the response of bacterial communities and OPAHs dissipation was also explored. The initial content of OPAHs in the soil was 34.6 mg·kg-1. The dissipation of OPAHs in the soil on day 14 was inhibited by LDPE. The contents of OPAHs in LDPE groups were higher than that in the control by 0.9-1.6 mg·kg-1, and the inhibition degree increased with the proportion of LDPE. The contents of OPAHs were not significantly different among groups on day 28, indicating that the inhibitory effect of LDPE disappeared. LDPE did not change the composition of the dominant taxa in the OPAHs-contaminated soil community but influenced the relative abundances of some dominant taxa. LDPE increased the relative abundance of Proteobacteria and Actinobacteria at the phylum level and decreased that of Bacillus and increased those of Micromonospora, Sphingomonas, and Nitrospira (potential degrading bacteria of LDPE and endogenous substances) at the genus level, all four of which were the main genera dominating intergroup community differences. LDPE changed the α and ß diversity of bacterial communities, but the extents were not significant. LDPE affected the function of the bacterial community, reducing the total abundance of PAHs-degrading genes and some degrading enzymes, inhibiting the growth of PAHs-degrading bacteria and thus interfering with the natural decay of OPAHs.

[Aging and Small-sized Particles Release Characteristics of Tire Microplastics in Various Environmental Media].

In recent years, research on microplastics has mostly focused on thermoplastic materials, and there is a lack of research on the pollution status and environmental behavior of tire microplastics, a type of rubber elastomers. In order to investigate the aging and small-sized particles release characteristics of tire microplastics in various environmental media, the aging process of two different tire microplastics, one for cars and the other for electric bicycles, was simulated in dry and aquatic environments under laboratory conditions. The results showed that the tire microplastics would be aged after 30 d of UV illumination, which was manifested by the roughness of the surface and the appearance of cracks and flaking. The Fourier infrared spectra showed that the carbonyl index of the surface also increased. In addition, tire microplastics released a large number of small sub-micron particles under the influence of UV illumination and hydrodynamic action, and the number of particles released from car tire microplastics in aquatic environments reached 694.8 million particles per milliliter of solution at 30 d of the UV light condition, among which 694.6 million particles with a particle size of less than 1 µm were released, which was approximately 100 times of that in the dark condition. The study showed that tire microplastics in aquatic environments were more susceptible to aging and released more small particles under light conditions and that car tire microplastics released more small particles than electric bicycle tire microplastics, posing ecological and environmental risks.

[Effect of Photoaging on Adsorption of Cu(â ¡) by Polystyrene Microplastics with Different Particle Sizes].

In order to evaluate the effect of aging and particle size on the adsorption of heavy metals by microplastics, the adsorption behavior of Cu(Ⅱ) by three different particle sizes of polystyrene (PS; 1, 50, and 100 µm) under UV irradiation was systematically studied. The results demonstrated that UV aging significantly changed the surface morphology and physicochemical properties of PS, and 1 µm PS had the strongest aging degree. The adsorption kinetics of PS on Cu(Ⅱ) conformed to the pseudo-second-order kinetic model, and the Freundlich model was more suitable for the experimental data of isothermal adsorption of Cu(Ⅱ) by PS. These results indicated that the adsorption of Cu(Ⅱ) by PS occurred on the non-uniform surface of PS, and the adsorption behavior was multilayer adsorption. Parameter "n" of the Freundlich model was less than 1, indicating that the adsorption behavior of PS on Cu(Ⅱ) was a higher intensity physical adsorption behavior. The order of theoretical maximum adsorption capacity of different particle sizes PS for Cu(Ⅱ) was as follows:1 µm > 50 µm > 100 µm, indicating that the size of PS was an important influence factor for the adsorption capacity of PS to pollutants. For the same particle size PS, aging enhanced its adsorption capacity for Cu(Ⅱ). The results on the adsorption of Cu(Ⅱ) by PS under different environmental conditions indicated that the adsorption capacity of PS for Cu (II) increased with the increase in pH, whereas an increase in salinity had the opposite effect. Surface complexation and electrical adsorption were the main mechanisms of adsorption of Cu(Ⅱ) by PS. This study provides an important scientific basis for understanding the adsorption behavior of microplastics to heavy metals in the environment.

Probiotics an emerging therapeutic approach towards gut-brain-axis oriented chronic health issues induced by microplastics: A comprehensive review.

Applications for plastic polymers can be found all around the world, often discarded without any prior care, exacerbating the environmental issue. When large waste materials are released into the environment, they undergo physical, biological, and photo-degradation processes that break them down into smaller polymer fragments known as microplastics (MPs). The time it takes for residual plastic to degrade depends on the type of polymer and environmental factors, with some taking as long as 600 years or more. Due to their small size, microplastics can contaminate food and enter the human body through food chains and webs, causing gastrointestinal (GI) tract pain that can range from local to systemic. Microplastics can also acquire hydrophobic organic pollutants and heavy metals on their surface, due to their large surface area and surface hydrophobicity. The levels of contamination on the microplastic surface are significantly higher than in the natural environment. The gut-brain axis (GB axis), through which organisms interact with their environment, regulate nutritional digestion and absorption, intestinal motility and secretion, complex polysaccharide breakdown, and maintain intestinal integrity, can be altered by microplastics acting alone or in combination with pollutants. Probiotics have shown significant therapeutic potential in managing various illnesses mediated by the gut-brain axis. They connect hormonal and biochemical pathways to promote gut and brain health, making them a promising therapy option for a variety of GB axis-mediated illnesses. Additionally, taking probiotics with or without food can reduce the production of pro-inflammatory cytokines, reactive oxygen species (ROS), neuro-inflammation, neurodegeneration, protein folding, and both motor and non-motor symptoms in individuals with Parkinson's disease. This study provides new insight into microplastic-induced gut dysbiosis, its associated health risks, and the benefits of using both traditional and next-generation probiotics to maintain gut homeostasis.

Changes in the Chemical Composition of Polyethylene Terephthalate Under UV Radiation in Various Environmental Conditions.

Polyethylene terephthalate has been widely used in the packaging industry. Degraded PET micro-nano plastics could pose public health concerns following release into various environments. This study focuses on PET degradation under ultraviolet radiation using the NIST SPHERE facility at the National Institute of Standards and Technology in saturated humidity (i.e., ≥ 95 % relative humidity) and dry conditions (i.e., ≤ 5 % relative humidity) with varying temperatures (30 °C, 40 °C, and 50 °C) for up 20 days. ATR-FTIR was used to characterize the chemical composition change of degraded PET as a function of UV exposure time. The results showed that the cleavage of the ester bond at peak 1713 cm-1 and the formation of the carboxylic acid at peak 1685 cm-1 are significantly influenced by UV radiation. Furthermore, the formation of carboxylic acid was considerably higher at saturated humidity and 50 °C conditions compared to dry conditions. The ester bond cleavage was also more pronounced in saturated humidity conditions. The novelty of this study is to provide insights into the chemical degradation of PET under environmental conditions, including UV radiation, humidity, and temperature. The results can be used to develop strategies to reduce the environmental impact of plastic pollution.

Spatial distribution of small microplastics in the Norwegian Coastal Current.

High concentrations of microplastic (MP) particles have been reported in the Arctic Ocean. However, studies on the high-resolution lateral and vertical transport of MPs from the European waters to the Arctic are still scarce. Here, we provide information about the concentrations and compositions of MPs in surface, subsurface, and deeper waters (< 1 m, ∼ 4 m, and 17-1679 m) collected at 18 stations on six transects along the Norwegian Coastal Current (NCC) using an improved Neuston Catamaran, the COntinuos MicroPlastic Automatic Sampling System (COMPASS), and in situ pumps, respectively. FTIR microscopy and spectroscopy were applied to measure MP concentration, polymer composition, and size distribution. Results indicate that the concentrations of small microplastics (SMPs, <300 µm) varied considerably (0-1240 MP m-3) within the water column, with significantly higher concentrations in the surface (189 MP m-3) and subsurface (38 MP m-3) waters compared to deeper waters (16 MP m-3). Furthermore, the average concentration of SMPs in surface water samples was four orders of magnitude higher than the abundance of large microplastics (LMPs, >300 µm), and overall, SMPs <50 µm account for >80 % of all detected MPs. However, no statistically significant geographical patterns were observed in SMP concentrations in surface/subsurface seawaters between the six sampling transects, suggesting a relatively homogeneous horizontal distribution of SMPs in the upper ocean within the NCC/Norwegian Atlantic Current (NwAC) interface. The Lagrangian particle dispersal simulation model further enabled us to assess the large-scale transport of MPs from the Northern European waters to the Arctic.

Review of microplastics and chemical risk posed by plastic packaging on the marine environment to inform the Global Plastics Treaty.

Plastic overproduction and the resulting increase in consumption has made plastic pollution ubiquitous in all ecosystems. Recognizing this, the United Nations (UN) has started negotiations to establish a global treaty to end plastic pollution, especially in the marine environment. The basis of the treaty has been formulated in terms of turning off the tap, signaling the will to prevent plastic pollution at its source. Based on the distribution of plastic production by sector, the plastic packaging sector consumes the most plastic. The volume and variety of chemicals used in plastic packaging, most of which is single-use, is a major concern. Single-use plastics including packaging is one of the most dominant sources of plastic pollution. Plastic waste causes pollution in water, air and soil by releasing harmful chemicals into the environment and can also lead to exposure through contamination of food with micro- and nano-plastic particles and chemicals through packaging. Marine life and humans alike face risks from plastic uptake through bioaccumulation and biomagnification. While the contribution of plastics ingested to chemical pollution is relatively minor in comparison to other pathways of exposure, the effect of plastic waste on marine life and human consumption of seafood is beyond question. To reduce the long-term impact of plastic, it is crucial to establish a global legally binding instrument to ensure the implementation of upstream rather than downstream solutions. This will help to mitigate the impact of both chemicals and microplastics, including from packaging, on the environment.

Combined effects of polyethylene terephthalate and abamectin on enzymatic activity and histopathology response in juvenile zebrafish (Danio rerio).

One of the most pressing global environmental issues is the widespread abundance and distribution of microplastics (MPs). MPs can act as vectors for other contaminants in the environment making these small plastic particles hazardous for ecosystems. The presence of MPs in aquatic environments may pose threats to aquatic organisms that ingest them. This study examined effects of abamectin (ABM) and polyethylene terephthalate (PET) MP fragments on histopathological and enzymatic biomarkers in zebrafish (Danio rerio). Zebrafish were exposed for 96 h to pristine PET-MPs at concentrations of 5 mg/L and 10 mg/L, ABM alone at 0.006 mg/L, and the same concentration of ABM in the presence of PET-MPs in aquaria. Histopathological analysis revealed tissue content changes in liver and kidney in the presence of ABM individually and in combination with MPs. Results of enzymatic analysis showed that MPs increased the bioavailability and toxicity of pesticides due to inhibition of catalase (CAT) and acid phosphatase (ACP) enzymes. However, MPs did not affect the toxicity of ABM for glutathione s-transferase (GST) enzyme. Despite the inhibition of acetylcholinesterase (AChE) in MPs or ABM treatments, and some neurotoxicity, no change in activity of this enzyme and neurotoxicity was observed in the combined MPs and ABM treatments, although toxicity effects of MPs and ABM on zebrafish require more detailed studies.

Assessment of coastal pollutants and health status of Pacific oysters (Magallana gigas) in the Bahía Blanca Estuary and adjacent beaches (Argentina).

This study assessed the effects of pollutants on Magallana gigas along a coastal zone with different levels of human activity: a highly impacted zone in the Bahía Blanca Estuary and a less impacted zone on the adjacent sandy beaches. Oysters collected in 2021 were analyzed for various factors, including metals, polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides, microplastics, oxidative stress and histology. Oysters of both environments exhibited detectable concentrations of all these pollutants in their tissues. However, the estuarine oysters showed higher concentrations of Zn, Cu and As and total PAHs than the beach oysters. Banned organochlorine pesticides were detected only in beach oysters. Estuarine oysters displayed morphological changes in their digestive gland including a reduction in the mean epithelial thickness of the tubule and elevated lipid peroxidation levels, indicating cellular damage. This study underscores the widespread presence of pollutants in M. gigas, indicating the need for effective strategies to safeguard coastal ecosystem health.

Impact on sulfadiazine bio-accessibility in soils through organic diffusive gradients in thin films (o-DGT): Differentiation based on microplastic polymers, aging, and soil properties.

Due to the similar sources of swage irrigation, organic fertilizer, and sludge application, microplastics (MPs) and antibiotics coexist inevitably in the agriculture soils. However, the impacts of MPs with different polymer types and aging status on the bio-accessibility of co-existing antibiotics in soils remained unclear. Therefore, we using the diffusive gradients films for organic compounds devices (o-DGT) to evaluated the distribution of sulfadiazine (SDZ) in both paddy soil and saline soil amended with 0.5 % (w/w) MPs. Four polymer types (polyethylene: PE, polypropylene: PP, polyamide: PA, and polyethylene terephthalate: PET) and two aging statuses (aged PE and aged PP) of MPs were used in this study. Results showed that soil properties significantly influence the partition of SDZ in soil and soil solution, and SDZ gained a lower degradation rate but higher mobility in saline soil. MPs pose different impacts on partition of SDZ between paddy soil and saline soil. Notably, PP reduced the labile solid phase-solution phase partition coefficient (Kdl) by 17.7 % in paddy soil, while PE, PP, and aPE increased the Kdl value by 2.00, 1.62, and 2.81 times in saline soil. Besides, in saline soil, all the MPs reduced the SDZ concentration in the soil solution, while significantly increased the SDZ in o-DGT phase. Conversely, MPs did not impact the SDZ's o-DGT concentration in paddy soil. Additionally, MPs increased the R value of SDZ in two soils, especially in saline soil. It suggested that MPs could potentially enhance the resupply of SDZ from soil to plants, particularly under saline conditions. Furthermore, aged MPs had a more pronounced effect on these indicators compared to virgin MPs in saline soil. Therefore, MPs in soil poses a potential risk for biota's uptake of SDZ, particularly in fragile environment. Moreover, the risk intensifies with aged MPs.

Unveiling the Tiny Invaders: A deep dive into microplastics in shrimp - Occurrence, detection and unraveling the ripple effects.

Aquaculture is a rapidly expanding food sector worldwide; it is the farming of fish, shellfish, and other marine organisms. Microplastics (MPs) are small pieces of plastic with a diameter of less than 5 mm that end up in the marine environment. MPs are fragments of large plastics that take years to degrade but can frustrate into small pieces, and some commercially available MPs are used in the production of toothpaste, cosmetics, and aircraft. MPs are emerging contaminants; they are ingested by marine species. These MPs have effects on marine species such as growth retardation and particle translocation to other parts of the body. Recently, MPs accumulation has been observed in shrimps, as well as in a wide range of other scientific reports. So, in this study, we review the presence, accumulation, and causes of MPs in shrimp. These plastics can trophic transfer to other organisms, changes in plastic count, effects on the marine environment, and impacts of MPs on human health were also discussed. It also improves our understanding of the importance of efficient plastic waste management in the ocean, as well as the impact of MPs on marine biota and human health.

Surface wettability control and electron transport regulation in zerovalent iron for enhanced removal of emerging polystyrene microplastics-heavy metal contaminants.

Emerging microplastics-heavy metal (MPs-HM) contaminants in wastewaters pose an emerging health and environmental risk due to their persistence and increasing ecological risks (e.g., "Trojan horse" effect). Hence, removing MPs in solution and preventing secondary releases of HM has become a key challenge when tackling with MPs pollution. Leveraging the hydrophobic nature of MPs and the electron transfer efficiency from Fe0 to HM, we demonstrate an alkylated and sulfidated nanoscale zerovalent iron (AS-nZVI) featuring a delicate "core-shell-hydrophobic film" nanostructure. Exemplified by polystyrene (PS) MPs-Pb(II) removal, the three nanocomponents offer synergistic functions for the rapid separation of MPs, as well as the reduction and stabilization of Pb(II). The outmost hydrophobic film of AS-nZVI greatly improves the anticorrosion performance of nanoscale zerovalent iron and the enrichment abilities of hydrophobic MPs, achieving a maximum removal capacity of MPs to 2725.87 mgMPs·gFe-1. This MPs enrichment promotes the subsequent reductive removal of Pb(II) through the electron transfer from the iron core of AS-nZVI to Pb(II), a process further strengthened by the introduced sulfur. When considering the inevitable aging of MPs in wastewaters due to mechanical wear or microbial degradation, our study concurrently examines the efficiencies and behaviors of AS-nZVI in removing virgin-MPs-Pb(II) and aged-MPs-Pb(II). The batch results reveal that AS-nZVI has an exceptional ability to remove above 99.6 % Pb(II) for all reaction systems. Overall, this work marks a pioneering effort in highlighting the importance of MPs-toxin combinations in dealing with MPs contamination and in demonstrating the utility of nZVI techniques for MPs-contaminated water purification.

Atlas and source of the microplastics of male reproductive system in human and mice.

Regarding the impact of microplastics (MPs) on the male reproductive system, previous studies have identified a variety of MPs in both human semen and testicular samples. These studies have put forward the hypothesis that small particles can enter the semen through the epididymis and seminal vesicles. Here, we performed qualitative and quantitative analyses of MPs in human testis, semen, and epididymis samples, as well as in testis, epididymis, seminal vesicle, and prostate samples from mice via pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The goal of this approach was to comprehensively characterize the distribution of MPs within the male reproductive system. Additionally, we aimed to evaluate potential sources of MPs identified in semen, as well as to identify possible sources of overall MP exposure. Our results highlighted a general atlas of MPs in the male reproductive system and suggested that MPs in semen may originate from the epididymis, seminal vesicles, and prostate. An exposure questionnaire, coupled with the characteristics of the MPs detected in the male reproductive system, revealed that high urbanization, home-cooked meals, and using scrub cleansers were important sources of MP exposure in men. These findings may provide novel insights into alleviating the exposure of men to MPs.

Influencing mechanisms of microplastics existence on soil heavy metals accumulated by plants.

Microplastics (MPs) and heavy metals often coexist in soil, drawing significant attention to their interactions and the potential risks of biological accumulation in the soil-plant system. This paper comprehensively reviews the factors and biochemical mechanisms that influence the uptake of heavy metals by plants, in the existence of MPs, spanning from rhizospheric soil to the processes of root absorption and transport. The paper begins by introducing the origins and current situation of soil contamination with both heavy metals and MPs. It then discusses how MPs alter the physicochemical properties of rhizospheric soil, with a focus on parameters that affect the bioavailability of heavy metals such as aggregates, pH, Eh, and soil organic carbon (SOC). The paper also examines the effect of this pollution on soil organisms and plant growth and reviews the mechanisms by which MPs affect the bioavailability and movement-transformation of heavy metals in rhizospheric soil. This examination emphasizes the roles of rhizospheric microbes, soil fauna, and root physiological metabolism. Finally, the paper outlines the research progress on the mechanisms by which MPs influence the uptake and transport of heavy metals by plant roots. Through this comprehensive review, this paper provides aims to provide environmental managers with a detailed understanding of the potential impact of the coexistence of MPs and heavy metals on the soil-plant ecosystem.