Modeling multi-source plastic pollution yield and transport driven by catchment hydrometeorological processes.

Plastic pollution has emerged as a global environmental concern, impacting both terrestrial and marine ecosystems. However, understanding of plastic sources and transport mechanism at the catchment scale remains limited. This study introduces a multi-source plastic yield and transport model, which integrates catchment economic activities, climate data, and hydrological processes. Model parameters were calibrated using a combination of field observations, existing literature, and statistical random sampling techniques. The model demonstrated robust performance in simulating both plastic yield and transport from 2010 to 2020 in the upper and middle Mulan River Catchment, located in southeast China. The annual average yield coefficients were found to closely align with existing estimations, and the riverine outflow exhibited a high correlation coefficient of 0.97, with biases ranging from -63.0 % to -21.4 % across all monitoring stations. The analysis reveals that, on average, 12.5 ± 2.5 % of the total plastic yield is transported to rivers annually, with solid waste identified as the primary source, accounting for 37.8 ± 20.7 % of the total load to rivers, followed by agricultural film (26.4 ± 9.8 %), impermeable surfaces (21.5 ± 10.3 %), urban and rural sewage (10.4 ± 5.0 % and 3.0 ± 1.5 %, respectively), and industrial wastewater (0.9 ± 0.7 %). The annual average outflow was estimated to between 9.3 and 43.0 ton/year (median: 23.1) at a 95 % confidence level. This study not only provides insights into the primary sources and transport pathways of plastic pollution at the catchment scale, but also offers a valuable tool for informing effective plastic pollution mitigation strategies.

Unveiling Small-Sized Plastic Particles Hidden behind Large-Sized Ones in Human Excretion and Their Potential Sources.

Health risks of microplastic exposure have drawn growing global concerns due to the widespread distribution of microplastics in the environment. However, more evidence is needed to understand the exposure characteristics of microplastics owing to the limitation of current spectrum technologies, especially the missing information on small-sized particles. In the present study, laser direct infrared spectroscopy and thermal desorption-gas chromatography-mass spectrometry combined pyrolysis using a tubular furnace (TD-GC/MS) were employed to comprehensively detect the presence of plastic particles down to 0.22 µm in human excreted samples. The results showed that polyethylene (PE), polyvinyl chloride, PE terephthalate (PET), and polypropylene dominated large-sized (>20 µm) and small-sized plastic plastics (0.22-20 µm) in feces and urine. Moreover, fragments accounted for 60.71 and 60.37% in feces and urine, respectively, representing the most pervasive shape in excretion. Surprisingly, the concentration of small-sized particles was significantly higher than that of large-sized microplastics, accounting for 56.54 and 50.07% in feces (345.58 µg/g) and urine (6.49 µg/mL). Significant positive correlations were observed between the level of plastic particles in feces and the use of plastic containers and the consumption of aquatic products (Spearman correlation analysis, p < 0.01), suggesting the potential sources for plastic particles in humans. Furthermore, it is estimated that feces was the primary excretory pathway, consisting of 94.0% of total excreted microplastics daily. This study provides novel evidence regarding small-sized plastic particles, which are predominant fractions in human excretion, increasing the knowledge of the potential hazards of omnipresent microplastics to human exposure.

Recent advances and prospects of neonicotinoid insecticides removal from aquatic environments using biochar: Adsorption and degradation mechanisms.

In recent years, neonicotinoid insecticides (NNIs), representing a new era of pest control, have increasingly replaced traditional classes such as organophosphorus compounds, carbamates, and pyrethroids due to their precise targeting and broad-spectrum efficacy. However, the high water solubility of NNIs has led to their pervasion in aquatic ecosystems, raising concerns about potential risks to non-target organisms and human health. Therefore, there is an urgent need for research on remediating NNI contamination in aquatic environments. This study demonstrates that biochar, characterized by its extensive surface area, intricate pore structure, and high degree of aromaticity holds significant promise for removing NNIs from water. The highest reported adsorption capacity of biochar for NNIs stands at 738.0 mg·g-1 with degradation efficiencies reaching up to 100.0 %. This review unveils that the interaction mechanisms between biochar and NNIs primarily involve π-π interactions, electrostatic interactions, pore filling, and hydrogen bonding. Additionally, biochar facilitates various degradation pathways including Fenton reactions, photocatalytic, persulfate oxidations, and biodegradation predominantly through radical (such as SO4-, OH, and O2-) as well as non-radical (such as 1O2 and electrons transfer) processes. This study emphasizes the dynamics of interaction between biochar surfaces and NNIs during adsorption and degradation aiming to elucidate mechanistic pathways involved as well as assess the overall efficacy of biochar in NNI removal. By comparing the identification of degradation products and degradation pathways, the necessity of advanced oxidation process is confirmed. This review highlights the significance of harnessing biochar's potential for mitigating NNI pollution through future application-oriented research and development endeavors, while simultaneously ensuring environmental integrity and promoting sustainable practices.

Application of TCM Nursing in Post-anesthesia Recovery Room Under Integrated Management Mode.

Objective: To explore the effect of traditional Chinese medicine (TCM) nursing under the integrated management mode during anesthesia recovery. Methods: The researchers' hospital admitted 114 patients who underwent general anesthesia between August 2022 and April 2023. Based on the admission order, these patients were divided into a control group (N=57) and an observation group (N=57). The control group received routine nursing intervention, while the observation group received comprehensive TCM nursing management, which included therapies such as cupping, acupressure, massage, herbal decoction, and mirabilite application. The study evaluated the psychological status, recovery indexes after anesthesia, comfort level, incidence of complications, and patient satisfaction with nursing care. Results: Compared to the control group, the observation group showed significant improvement in their psychological well-being (P < .05) and better recovery outcomes after anesthesia (P < .05). Additionally, the observation group reported higher levels of comfort (P < .05), a lower incidence of complications (8.77% vs 29.82%, P < .05), and greater satisfaction with nursing care (98.25% vs 84.21%, P < .05) compared to the control group. Conclusion: Integrated management of traditional Chinese medicine effectively reduces postoperative adverse events, improves treatment outcomes, and facilitates patient recovery. Its benefits are evident, and its feasibility is well-established.

Tissue accumulation of microplastics and potential health risks in human.

Microplastics have become ubiquitous throughout the environment. Humans constantly ingest and inhale microplastics, increasing concerns about the health risks of microplastic exposure. However, limited data impedes a full understanding of the internal exposure to microplastics. Herein, to evaluate microplastic exposure via the respiratory and digestive systems, we used laser direct infrared spectroscopy to identify microplastics >20 µm in size in different human tissues. Consequently, 20-100 µm microplastics were concentrated in all tissues, with polyvinyl chloride (PVC) being the dominant polymer. The highest abundance of microplastics was detected in lung tissue with an average of 14.19 ± 14.57 particles/g, followed by that in the small intestine, large intestine, and tonsil (9.45 ± 13.13, 7.91 ± 7.00, and 6.03 ± 7.37 particles/g, respectively). The abundance of microplastics was also significantly greater in females than in males (p < 0.05). Despite significant diversity, our estimation showed that the lungs accumulated the highest amounts of microplastic. Moreover, PVC particles may cause potential health risks because of their high polymer hazard index and maximal risk level. This study provides evidence regarding the occurrence of microplastics in humans and empirical data to support assessments of the health risks posed by microplastics.

[Research Progress on Characteristics of Human Microplastic Pollution and Health Risks].

Microplastic pollution is not only an environmental problem but also a social problem. Many studies have been conducted on the sources, abundance, and distribution of microplastics in the environment, but an understanding of human exposure levels and potential health risks remains very limited. Based on the bibliometric methods, the present review systematically summarized the exposure pathways of microplastics in humans, and then the characteristics and potential adverse impacts on human health were expounded upon. Available literature showed that microplastics in human bodies were mainly concentrated on sizes smaller than 50 µm, and polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) were the main polymers. Microplastics in environments entered human bodies mainly through food and respiratory pathways, then accumulated in lung and gastrointestinal tissues. Most importantly, small-sized microplastics could distribute in tissues and organs via the circulatory system. The results from lab-based toxicological experiments showed that microplastics not only posed threats to cell membrane integrity, immune stress, gut microbiota, and energy metabolism but also had potentially adverse impacts on the reproductive system. To further understand the health risks of microplastic pollution, it is necessary to promote research on the toxicological effects of microplastics as well as the inner mechanisms and also to establish risk assessment frameworks for evaluating microplastic pollution. These works are crucial to preventing the risks of microplastic pollution with scientific evidence.

Study on the simultaneous release of microfiber and indigo dye in denim fabric home washing.

In recent years, with the increasing global focus on environmental protection, the issue of microfiber release from denim during the washing process has gained attention. In this study, a programmable washing device simulating household drum washing was designed and developed, microfibers and indigo dyes released from denim washing were quantitatively detected, and we have also developed a novel method for estimating the release of microfibers during washing. The effects of washing time, washing temperature, and washing load on microfiber and indigo dye release from denim were explored. The results showed that the effect of washing load on microfiber and indigo dye release was greater than washing temperature and washing time. The research findings indicate that with an increase in washing time (35-95 min) and washing load (100-250 g), the shedding of microfibers and indigo dye significantly increases, reaching peak release levels of 343.6 µg/g fabric and 0.027 mg/L, respectively. However, there is a decreasing trend in the release of microfibers and indigo dye when the washing temperature exceeds 50 °C. Furthermore, our data suggests that an increase in washing load leads to a significant change in the number of microfibers (from 978 items/g fabric to 1997 items/g fabric) and their mass (from 156.87 µg/g fabric to 343.56 µg/g fabric). The influence of washing time, washing temperature, and washing load on microfiber length shows relatively small fluctuations within the range of 600-900 µm. This study provides new ideas and methods for estimating the release of microfiber and indigo dye in denim washing around the world.

Potential Environmental Contaminants: Exploring Hydrolyzed Dyes in Household Washing Sources and Electrochemical Degradation.

Reactive dyes are often released into the environment during the washing process due to their susceptibility to hydrolysis. The hydrolysis experiment of a pure reactive dye, red 195 (RR 195), and the washing experiment of RR 195-colored fabrics (CFSCs) were carried out successively to explore the sources of hydrolyzed dyes in the washing microenvironment. Reversed-phase high-performance liquid chromatography (RP-HPLC) was used for the analysis of hydrolysis intermediates and final products of reactive red 195. The experimental results indicated that the structure of the dye washing shed is consistent with the final hydrolysate of reactive red 195, which is the main colored contaminant in washing wastewater. To eliminate the hydrolyzed dyes from the source, an electrochemical degradation device was designed. The degradation parameters, including voltage, electrolyte concentration, and dye shedding concentration are discussed in the electrochemical degradation experiment. The electrochemical degradation device was also successfully implemented and verified in a home washing machine.

Microplastics transferring from abiotic to biotic in aquatic ecosystem: A mini review.

Microplastics have been detected in global aquatic ecosystems, so it is vital to understand the bioaccumulation and biomagnification of microplastics for ecological risk assessment. However, variability between studies, including sampling, pretreatment processes, and polymer identification methods have made it difficult to draw definitive conclusions. Alternatively, the compilation and statistical analysis of available experimental and investigation data provides insight into the fates of microplastics in an aquatic ecosystem. To reduce bias, we performed a systematic literature retrieval and compiled these reports on microplastic abundance in the natural aquatic environment. Our results indicate that microplastics are more abundant in sediments than in water, mussels, and fish. There is a significant correlation between mussels and sediments, but not between water and mussels or between water/sediment and fish. Bioaccumulation of microplastics appears to occur through water, but the route of biomagnification is unclear. More sound evidence is required to fully understand the biomagnification of microplastics in aquatic environments.

Transport of neonicotinoid insecticides in a wetland ecosystem: Has the cultivation of different crops become the major sources?

Extensive application of neonicotinoid insecticides (NNIs) in agricultural production has resulted in widespread contamination of multiple environmental media. To investigate the occurrence and fate of NNIs in the largest marsh distribution area in Northeast China, an integrated ecosystem covering farmlands, rivers, and marshes, referred to as the farmland-river-marsh continuum in this study, was chosen for soil, water, and sediment sampling. Five NNIs were detected, with imidacloprid (IMI), thiamethoxam (THM), and clothianidin (CLO) being the most frequently detected ones in different samples. Concentrations of target NNIs in soil, surface water, and sediment samples were 2.23-136 ng/g dry weight (dw), 3.20-51.7 ng/L, and 1.53-8.40 ng/g dw, respectively. In soils, NNIs were detected more often and at higher concentrations in upland fields, while the concentration of NNIs in the soybean-growing soils (71.5 ng/g dw) was significantly higher than in the rice-growing soils (18.5 ng/g dw) (p < 0.05). Total concentration of NNIs in surface water was lower in the Qixing River channel than inside the marsh, while that in sediments showed an opposite trend. Total migration mass of IMI from approximately 157,000 ha of farmland soil by surface runoff was estimated to be 2636-3402 kg from the application time to the sampling period. The storage of NNIs in sediments was estimated to range from 45.9 to 252 ng/cm2. The estimated environmental risks, calculated as the risk quotients (RQs), revealed low risks to aquatic organisms (RQs <0.1) from the residual concentrations of NNIs in water.

Potential translocation process and effects of polystyrene microplastics on strawberry seedlings.

A growing body of concerns focuses on microplastics as an emerging threat to terrestrial soil-plant ecosystems, but few previous studies have concentrated on asexual plants. To fill this knowledge gap, we carried out a biodistribution study of polystyrene microplastics (PS-MPs) of different particle sizes in strawberry (Fragaria × ananassa Duch. cv. "Akihime") seedlings via the hydroponic cultivation method. Confocal laser scanning microscopy (CLSM) results indicated that both 100 and 200 nm PS-MPs entered the roots and were further translocated to the vascular bundle through the apoplastic pathway. Both PS-MP sizes were detected in the vascular bundles of the petioles after 7 d of exposure, indicating a xylem-based upward translocation pathway. After 14 d, continuous upward translocation of 100 nm PS-MPs was observed above the petiole, while 200 nm PS-MPs could not be directly observed in the strawberry seedlings. This means that the uptake and translocation of PS-MPs depended on the size of PS-MPs and appropriate timing. The significant influence of strawberry seedling's antioxidant, osmoregulation, and photosynthetic systems（p < 0.05）was presented at 200 nm PS-MPs than 100 nm PS-MPs. Our findings provide scientific evidence and valuable data for the risk assessment of PS-MP exposure in asexual plant systems such as strawberry seedlings.

Occurrence of microplastics in commercially sold bottled water.

Microplastics are ubiquitous in all environmental compartments, including food and water. A growing body of evidence suggests the potential health impacts of continuous microplastic ingestion on humans. However, a lack of information on microplastic exposure to humans through drinking water and the high heterogeneity of available data limits advancements in health risk assessments. In the present study, laser direct infrared spectroscopy (LD-IR) was used to determine the occurrence of microplastics in bottled water sold in China. Then, the ingestion level of microplastics through drinking water was estimated. The results showed that the average microplastic abundance in bottled water was 72.32 ± 44.64 items/L, which was higher than that detected in tap water (49.67 ± 17.49 items/L). Overall, the microplastic structures were dominated by films and mainly consisted of cellulose and PVC. Their sizes were concentrated in the range of 10-50 µm, accounting for 67.85 ± 8.40 % of the total microplastics in bottled water and 75.50 % in tap water. The estimated daily intake of microplastics (EDI) by infants through bottled water and tap water was almost twice as high as that by adults, although adults ingested more microplastics. The present results provide valuable data for further assessing human health risks associated with exposure to microplastics.

The toxicity of nano polyethylene terephthalate to mice: Intestinal obstruction, growth retardant, gut microbiota dysbiosis and lipid metabolism disorders.

Polyethylene terephthalate (PET) are widely used in our daily life while they may be broken to smaller fractions as nano-sized PET (nPET) in the environment. The toxicity of nPET is still less studied. This work first evaluated the LD50 of different size of nPET (200 nm, S-nPET; 700 nm, B-nPET) in mice, then studied the health effects of single exposure to S/B-nPET at 200 mg/kg bw for 30 days. It was found that the LD50 was 266 mg/kg bw for S-nPET and 523 mg/kg bw for B-nPET, respectively, showing a size-dependent effect. S-nPET caused weight loss, cyst, intestinal obstruction, organ damage and mortality (40%), and perturbed gut microbiome and metabolome especially lipid metabolism, such as upregulated cholesterol, glycocholic, propionic acid, niacinamide, ectoine and xanthine, and downregulated arachidonic acid, anserine, histamine, while B-nPET did not. Serological analysis found S-nPET brought more lipid metabolic immune and neurological damage than B-nPET, confirming the size-dependent effect. To the best of our knowledge, this is the first report on the systematic toxicity of nPET to mice. Further studies are warranted for life-long effects of nPET. The protocol applied in this work may also be used for the study of the health effects of other plastics.

Atmospheric microfibers dominated by natural and regenerated cellulosic fibers: Explanations from the textile engineering perspective.

A large number of synthetic fibers found in the environment have aroused public conern about microfiber pollution. However, more studies have found that the number of natural fibers and regenerated cellulose fibers in the environment is much higher than that of synthetic fibers. If humans are exposed to excessive amounts of these two types of fibers for a long time, they may also suffer physiological injury. However, this is often ignored by previous research on microfiber pollution. Recently, some publications attributed the dominating amounts of natural fiber and regenerated cellulosic fibers in the environment to the past yield advantage and low durability compared to synthetic fibers. This correspondence supports that view and further discusses the main reasons for the domination of natural and regenerated cellulosic fibers: their physicochemical properties, material sources, manufacturing processes (staple yarn and filament) and applications. This correspondence aims to arouse attention to the potential impact of natural fibers and regenerated cellulose fibers.

Identification of microplastics in human placenta using laser direct infrared spectroscopy.

Microplastics are ubiquitous in the environment, including in food and drinking water. Consequently, there is growing concern about the human health risks associated with microplastic exposure through diet. However, the occurrence of microplastics in the human body, particularly in mothers and fetuses, is incompletely understood because of the limited amount of data on their presence in the body and the human placenta. This study evaluated the presence and characteristics of microplastics in 17 placentas using laser direct infrared (LD-IR) spectroscopy. Microplastics were detected in all placenta samples, with an average abundance of 2.70 ± 2.65 particles/g and a range of 0.28 to 9.55 particles/g. Among these microplastics, 11 polymer types were identified. The microplastics were mainly composed of polyvinyl chloride (PVC, 43.27 %), polypropylene (PP, 14.55 %), and polybutylene succinate (PBS, 10.90 %). The sizes of these microplastics ranged from 20.34 to 307.29 µm, and most (80.29 %) were smaller than 100 µm. Most of the smaller microplastics were fragments, but fibers dominated the larger microplastics (200-307.29 µm). Interestingly, the majority of PVC and PP were smaller than 200 µm. This study provides a clearer understanding of the shape, size, and nature of microplastics in the human placenta. Importantly, these data also provide crucial information for performing risk assessments of the exposure of fetuses to microplastics in the future.

[Policy Analysis in Plastic Pollution Governance and Recommendations in China].

Plastic pollution is a global concern and an issue in environmental governance. Based on the updated "Plastic Prohibition/Restriction Order" issued recently in China, the present study systematically reviewed the implementation effectiveness of the "Plastic Prohibition/Restriction Order" since 2007. Furthermore, we summarized plastics in China and plastic waste management progress policies. Additionally, three deficiencies of the updated "Plastic Prohibition/Restriction Order" were discussed:policy formulation, implementation, and supervision. Some positive recommendations were provided based on the available reports, such as integrating plastic pollution into national basic laws and regulation systems, building a network platform for public attendance, and coordinating the publicity of the "Plastic prohibition/Restriction Order" with the public interest. Besides these measurements, some points about plastic waste management in the future were also highlighted, such as the "blind area" in small retail stores, the rational sharing of environmental protection responsibility, new materials and processes, and recycling and disposal systems for plastic wastes. Most importantly, the present study could provide ideas for policy-makers to address plastic pollution at its sources.

Enhancing consumption responsibility to address global plastic pollution.

Plastic pollution is a global crisis, especially in the marine environment. Excessive consumption and unsound disposal are responsible for the constant accumulation of plastic waste, resulting in plastic litter and microplastic contamination on a global scale. Establishing a new global framework is regarded as a promising tool to address plastic pollution, including marine plastic litter. However, there is a need to raise awareness of the role of consumers at individual and national levels in reducing the use of unnecessary plastics and increasing the recycling of plastic waste. The global framework should incorporate aspects of the importance of consumption responsibility in solutions addressing the issue of plastic pollution.

A case study on small-size microplastics in water and snails in an urban river.

Microplastic pollution has become pervasive in aquatic ecosystems. They readily interact with aquatic biota, potentially subjecting them to ecological and health risks. Urban rivers are also affected by microplastics due to intense anthropogenic activity. Nevertheless, relatively little is known about the physiocochemistry or ecotoxicology of microplastics in urban rivers. The present study used laser direct infrared chemical imaging to investigate microplastic pollution in a highly urbanized river in Beijing, China. Surface water was sampled at five sites along the river in March and July, and the benthic snail Bellamya aeruginosa was also collected at each location in July. Thirteen and fifteen different polymers were detected and identified in the surface water sampled in March and July, respectively. Thirteen different polymers were found and isolated in the snails. Of these, polypropylene, polyamide and polyethylene predominated in the microplastic particles. Moreover, the average abundance of the microplastic was significantly higher in the surface water sampled in July (39.55 ± 4.78 particles L-1) than in March (22.00 ± 4.87 particles L-1) (p < 0.05). The average microplastic abundance of snails across all sites was 28.13 ± 4.18 particles, among which the Q2 site has significantly higher microplastic abundance than station Q3-Q5 (p < 0.05). Microplastic particles 10-100 µm in size predominated in both the surface water and the snails. By contrast, the proportions of microplastic particles 200-500 µm in size were substantially smaller. The measured microplastic pollution load and microplastic pollution risk indices in the surface water indicated that the current microplastic pollution level in the Qing River was moderate from upstream to downstream. Moreover, the potential adverse effects of microplastic particles on snails remain unclear. Further research is required to elucidate small-size microplastics' environmental fate and potential ecological risks in urban rivers.

Microfiber releasing into urban rivers from face masks during COVID-19.

Face masks play a crucial protective role in preventing the spread of coronavirus disease during the COVID-19 pandemic, but the improper disposal of used face masks also causes an emerging environmental problem, such as microplastic contamination. Here, the aim was to evaluate the improper disposal of used face masks and, subsequently, the potential contribution to microplastic contamination in urban rivers. First, we investigated the occurrence of discarded face masks in Qing River through continuously one-month collection on-site, and the disposable masks with a density of (8.28 ± 4.21) × 10-5 items/m2 with varying degrees of wear and tear were found. Next, the microfibers shedding from two popular types of new disposable masks were tested. The results showed that 50.33 ± 18.50 items/mask of microfibers, ranging from 301 µm to 467 µm in size, were released from the disposal face mask after immersion in ultrapure water for 24-h. It was significantly higher than the KN95 respirator of 31.33 ± 0.57 items/mask, ranging from 273 µm to 441 µm. Besides C and O elements only found in new face masks, some potentially toxic elements were also detected on the surface of discarded face masks, indicating that various environmental contaminations are easy to adsorb on the surface of discarded face masks. The results implied that these discarded face masks in an aquatic environment are emerging sources of microfibers and could act as transport vectors for contaminants, which would aggravate the present microplastic contamination. In conclusion, these findings were expected to raise public awareness of the proper disposal of used face masks to prevent microplastic contamination and the spread of COVID-19 in the environment.