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Microplastics are an emerging anthropogenic pollutant risk with a significant body of research dedicated to understanding the implications further. To generate the databases required to characterize the impact of microplastics on our environment, and improve recovery and recycling of current plastic materials, we need rapid, in-line characterization that can distinguish individual polymer types. Here, autofluorescence spectroscopy was investigated as an alternative characterization method to the current leading techniques based on vibrational spectroscopy. It was confirmed that the autofluorescence of seven common textile polymers (acrylic, polyester, nylon, polyethylene, polypropylene, cellulose/cotton, wool) arose due to the cluster-triggered emission phenomenon. Both simulated polymer aging via photooxidation and dyeing of the polymers were found to affect the resultant autofluorescence spectra. A total of 1485 spectra from 39 unique sample groups (polymer type, colour, and degree of photooxidation) were analysed via machine learning (k-means cluster analysis). Correct identification of the polymer type was achieved in 71% of the cases from only eight input values (normalized intensity values at three autofluorescence emission wavelengths, the total autofluorescence emission intensity, the sample RGB colour values, and the sample shape). This represents a significant step towards automated polymer identification at the sub-second time scales required for the in-line characterization of microplastics. [ABSTRACT FROM AUTHOR]

The use of biodegradable plastics has been proposed as an alternative to mitigate the pollution problem caused by traditional non‐biodegradable plastics. However, the relative impacts of both types of microplastics on plant community productivity and diversity is not known. Moreover, it is unclear whether soil biota can differentially mediate the impacts of biodegradable and non‐biodegradable microplastics on plant communities. In this study, we investigated the effects of biodegradable and non‐biodegradable microplastics on plant community biomass production and diversity, and whether soil biota mediate these effects. We employed a fully crossed factorial design, growing six plant communities in the presence or absence of 10 individual microplastics, and in live soil versus sterilized soil. We hypothesized that: (1) Biodegradable microplastics have a less negative effect on plant community biomass production and diversity compared to non‐biodegradable microplastics. (2) Soil biota differentially mediate the effects of biodegradable and non‐biodegradable microplastics on plant community biomass production and diversity. Statistical analyses that included all 10 microplastics yielded two main findings. First, live soil ameliorated the negative effects of biodegradable microplastics on community shoot biomass. Second, the presence of microplastics, rather than their biodegradability, significantly reduced community diversity. Separate analyses of individual microplastics suggest that these patterns were driven by specific microplastics. The biodegradable microplastic polybutylene succinate (PBS) was the main driver of the pattern observed in community shoot biomass. In contrast, the biodegradable microplastic polycaprolactone (PCL) and non‐biodegradable microplastics ethylene‐vinyl acetate (EVA) and polyvinyl chloride (PVC) were the main drivers of the pattern observed in community diversity. Further analyses excluding PBS from the global models, but including the other nine microplastics, revealed no significant differences in community shoot biomass and diversity between biodegradable and non‐biodegradable microplastics in live versus sterilized soil. Synthesis and applications. Our findings suggest that biodegradable microplastics, often considered environmentally friendly, are not necessarily less harmful than non‐biodegradable microplastics to the growth and diversity of plant communities. Some individual biodegradable microplastics, such as PBS, still pose significant ecological risks to plant community structure and productivity. However, the results also suggest that soil biota may mitigate the negative effects of some biodegradable microplastics. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are one of the major substantial pollutants in the environment and are stored in sediments worldwide, especially in marine environments. This study shed light on the abundance, distribution, sources and chemical composition of MPs present in the surface sediments collected from the shelf part of the southeast coast of India, Bay of Bengal. A total of twenty-seven surface sediment samples were collected to study MPs pollution. The abundance and morphological characteristics of MPs were determined by counting using an Olympus SXZ7 stereo microscope. Raman spectroscopy analysis was used to identify the polymer type of the MPs. The average abundance of MPs in the study area is 460±275 MPs/kg in dry sediment. Regarding colour, transparent particles were predominant (46.42%), followed by blue, green, brown, etc. With respect to particle shape and size, fibres and 500-µm sized MPs are abundant. Polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polystyrene (PS) are the polymer types characterised in the study area. The higher abundance of MPs in the study area can be attenuated to human interruptions, viz., tourism, fishing and inappropriate sewage disposal in the marine environment. In addition to this, population density also plays an important role in providing MPs to the marine environment. This study provides the most valuable data to extrapolate the research for mitigating MP pollution in oceans. It also informs mankind about their disastrous activities on the marine environment, which is expected to recuperate quickly and negatively impact human health and the functionality of the marine system. [ABSTRACT FROM AUTHOR]

This study examined plastics and toxic metals in municipal solid waste compost from various regions in Sri Lanka. Plastics were extracted using density separation, digested using wet peroxidation, and identified using Fourier Transform Infra-Red Spectroscopy in Attenuated Total Reflection mode. Compost and plastics were acid-digested to quantify total Cd, Cu, Co, Cr, Pb, and Zn concentrations and analyzed for the bioavailable fraction using 0.01 M CaCl2. Notably, plastics were highly abundant in most compost samples. The main plastic types detected were polyethylene, polypropylene, and cellophane. However, the average Cd, Cu, Co, Cr, Pb, and Zn levels were 0.727, 60.78, 3.670, 25.44, 18.95, and 130.7 mg/kg, respectively, which are well below the recommended levels. Zn was the most bioavailable (2.476 mg/kg), and Cd was the least bioavailable (0.053 mg/kg) metal associated with compost. The Contamination factor data show that there is considerable enhancement of Cd and Cu, however, Cr, Cu, Co, and Pb are at low contamination levels. Mean geo accumulation index values were 1.39, 1.07, − 1.06, − 0.84, − 0.32, and 0.08 for Cd, Cu, Co, Cr, Pb, and Zn. Therefore, the contamination level of compost samples with Cd and Cu ranges from uncontaminated to contaminated levels, whereas Co, Cr, Pb, and Zn are at uncontaminated levels. Despite no direct metal-plastic correlation, plastics in compost could harm plants, animals, and humans due to ingestion. Hence, reducing plastic and metal contamination in compost is crucial. [ABSTRACT FROM AUTHOR]

Microplastics have become a pressing environmental issue due to their widespread presence in our ecosystems. Among various plastic components, polyethylene (PE) is a prevalent and persistent contaminant. Hydrothermal gasification (HTG), a promising technology for converting PE into syngas, holds great promise for mitigating the microplastic problem. In this study, we employ ReaxFF molecular dynamics simulations to investigate the HTG process of PE, shedding light on the intricate relationships between temperature, water content, carbon conversion efficiency, and product distributions. The results reveal that hydrothermal gasification of PE is a complex process involving multiple reaction pathways. Consistently with experimental findings, the calculations indicate that the gas phase exhibits a substantial hydrogen fraction, reaching up to 70%. Interestingly, our simulations reveal a dual role of water content in the HTG process. On one hand, water enhances hydrogen production by promoting the gas formation. On the other hand, it elevates the activation energy required for PE decomposition. Depending on the water content, the calculated activation energies range from 176 to 268 kJ/mol, which are significantly lower than those reported for thermal gasification (TG). This suggests that HTG may be a more efficient route for PE conversion. Furthermore, this study highlights the importance of optimizing both temperature and water content in HTG systems to achieve high yields of hydrogen-rich syngas. The results obtained from our ReaxFF MD simulations demonstrate the robustness of this computational methodology in elucidating complex chemical reactions under extreme conditions. Our findings offer critical insights into the design of advanced waste management strategies for microplastics and contribute to the development of sustainable practices for resource recovery. This work underscores the potential of HTG as a key technology for addressing the global challenge of plastic pollution. [ABSTRACT FROM AUTHOR]

Microplastics and heavy metals are two different classes of pollutants that are often present in aquatic systems. However, the interaction between these two pollutants is poorly understood in freshwater systems. This research has examined the sorption of cadmium(II) ions onto polyethylene microplastic (PEMP) under freshwater conditions. The scanning electron microscope, X-ray diffraction, and Fourier transform infrared analyses confirmed the existence of different functional groups and the porous nature of the PEMP surface. The influences of physicochemical parameters such as the solution pH, contact time, and initial Cd(II) concentration have been examined. The Langmuir isotherm predicted the Cd(II) sorption capacity by PEMP at pH 5 as 1.37 mg/g. Several isotherm models were utilized, including the Freundlich, Langmuir, and Sips models. The results confirmed that the Sips model has been more appropriate for Cd(II)-PEMP isotherm based on percentage errors and correlation coefficient values. Furthermore, the pseudo-first kinetic model fitted Cd(II)-PEMP more accurately than the pseudo-second kinetic equation. Desorption experiments were conducted to release Cd(II) ions from Cd(II)-bearing PEMP using different chemical agents. The findings showed that using 0.01 M nitric acid resulted in a desorption efficiency exceeding 99.8%. This demonstrates that microplastics loaded with Cd(II) may release Cd(II) ions in highly acidic environments, potentially allowing for the uptake of Cd(II) ions by aquatic organisms in their digestive tracts. [ABSTRACT FROM AUTHOR]

Plastic pollution has become a global problem since the extensive use of plastic in industries such as packaging, electronics, manufacturing and construction, healthcare, transportation, and others. This has resulted in an environmental burden that is continually growing, which has inspired many scientists as well as environmentalists to come up with creative solutions to deal with this problem. Numerous studies have been reviewed to determine practical, affordable, and environmentally friendly solutions to regulate plastic waste by leveraging microbes' innate abilities to naturally decompose polymers. Enzymatic breakdown of plastics has been proposed to serve this goal since the discovery of enzymes from microbial sources that truly interact with plastic in its naturalistic environment and because it is a much faster and more effective method than others. The scope of diverse microbes and associated enzymes in polymer breakdown is highlighted in the current review. The use of co-cultures or microbial consortium-based techniques for the improved breakdown of plastic products and the generation of high-value end products that may be utilized as prototypes of bioenergy sources is highlighted. The review also offers a thorough overview of the developments in the microbiological and enzymatic biological degradation of plastics, as well as several elements that impact this process for the survival of our planet. [ABSTRACT FROM AUTHOR]

This document discusses the ecological effects of micro(nano)plastics in the water environment. It highlights the accumulation and degradation of plastic products in aquatic systems, leading to the creation of micro- and nanoplastics. The document presents findings from a special issue collection, including studies on the impact of plastic litter on marine biodiversity, the toxicity of plastic additives to freshwater animals, the combined effect of microplastics and organic micropollutants on crustaceans, the toxic potential of conventional and compostable plastic particles for goldfish, the avoidance of plastic particles by climbing perch, and a method for detecting micro- and nanoplastics using the phototrophic behavioral response of crustaceans. The document concludes that more research is needed to understand the long-term effects of micro- and nanoplastics on aquatic species and calls for standardized testing methods for risk assessment of plastic contaminants in aquatic systems. [Extracted from the article]

Microplastic particles appear in great abundance and variety in freshwater ecosystems across the globe, spanning lakes and rivers, with increasingly frequent exposure of aquatic organisms. Studies on the mechanisms of any effects of plastic particles are still scarce, particularly in relation to the regenerative capacity of biota, for which there is no established model organism; however, planaria have shown sensitivity for assessing these risks to the aquatic environment. Thus, the present study aimed to investigate the behavioral and regeneration responses of the freshwater planaria Girardia tigrina exposed to polyethylene (PE) microplastics (MPs) incorporated into their food source. The greatest effect was observed on planarian regeneration, which was manifested at 10 μg/mg liver. Planaria reproduction and fertility were affected at 50 μg/mg liver; however, planaria locomotion was not affected at the concentrations evaluated. Mid-infrared absorption spectroscopy (FT-IR) was used to identify the constituent polymers, and ingestion of the polyethylene microplastic by the planaria was confirmed by infrared spectroscopy. The results highlight the potential adverse effects of exposure to polyethylene microplastic and show that the reproductive behavior and regeneration of a freshwater organism can be indicators of toxicity resulting from environmental pollution. [ABSTRACT FROM AUTHOR]

In the natural environment, plastics and microplastics (MPs) are difficult to break down due to their hydrophobicity, the presence of persistent covalent bonds, and their functional groups' resistance to attack. The destiny of both organic and inorganic pollutants at contaminated areas can be influenced by MPs ability to absorb them. Because of their enormous surface to volume ratio and chemical surface characteristics, MPs are able to absorb dangerous substances from their surroundings. Accordingly, the study's main objectives were to provide a concise review of characterization techniques of MP biodegradation techniques, including the nano‐enabled methods, and the gaps in current research were outlined. This review paper summarizes the degradation mechanism and efficiency of MPs in different circumstances. For the purpose of eliminating plastic pollution, this work will help for the further studies. [ABSTRACT FROM AUTHOR]

Virgin and environmentally aged polypropylene (PP) micropowders (V-PP and E-PP, respectively) were used as reference microplastics (MPs) in comparative photo- and thermo-oxidative ageing experiments performed on their mixtures with a natural ferrous sand (NS) and with a metal-free silica sand (QS). The ferrous NS was found to catalyze the photo-oxidative degradation of V-PP after both UV and simulated solar light irradiation. The catalytic activity in the V-PP/NS mixture was highlighted by the comparatively higher fraction of photo-oxidized PP extracted in dichloromethane, and the higher carbonyl index of the bulk polymer extracted with boiling xylene, when compared with the V-PP/QS mixture. Similarly, NS showed a catalytic effect on the thermal degradation (at T = 60 °C) of E-PP. The results obtained indicate that, under suitable environmental conditions (in this case, an iron-containing sediment or soil matrix, combined with simulated solar irradiation), the degradation of some types of MPs could be much faster than anticipated. Given the widespread presence of iron minerals (including the magnetite and iron-rich serpentine found in NS) in both coastal and mainland soils and sediments, a higher than expected resilience of the environment to the contamination by this class of pollutants is anticipated, and possible routes to remediation of polluted natural environments by eco-compatible iron-based minerals are envisaged. [ABSTRACT FROM AUTHOR]

Platforms are structures built by coypus for various purposes, such as reproduction, resting, and thermoregulation. In a coastal wetland of central Italy, during a study aimed at investigating the characteristics of coypu's platforms, it was recorded, for the first time worldwide, the presence of plastic in these structures. Through a transect survey, we censused 83 platforms, among which three (3.61%) were found with presence of macro- and megaplastics (polystyrene, polypropylene, and low-density polyethylene in film form; polyester, polyamide, and expanded polystyrene in fragments). Through the FTIR spectra, it was possible to highlight the degradation of the polymeric materials. To stimulate possible in-depth investigations at the level of the food chain (e.g., coypu predators, including canids) in wet habitats, we discussed possible causes and implications of plastic presence in coypus' nest structures. [ABSTRACT FROM AUTHOR]

As a way to reduce microplastics or nano-plastics in the ocean, it is of interest to develop biodegradable paper-based drinking straws to replace non-degradable plastic drinking straws. Primary questions to be addressed include how to design suitable coatings for paper drinking straws. Such coatings not only need to resist water. In addition, consumers have high expectations for the strength of a drinking straw. It is proposed here to replace non-biodegradable polypropylene, which is presently the main component of straws, with biodegradable and hydrophobic coating components via an entropy-driven approach. It is further proposed to develop colored paper-based drinking straws with cellulose nematic liquid crystal photonic pigments as a way to make the product stand out visibly, while at the same time mediating the usage of toxic chemical pigments. [ABSTRACT FROM AUTHOR]

The presence of perfluoroalkyl substances (PFAS) in the environment poses a significant threat to ecological safety and environmental health. Widespread microplastics (MPs) have been recognized as vectors for emerging contaminants due to human activities. However, the adsorption behaviors of PFAS on MPs, especially on aged MPs, have not been extensively investigated. This study aimed to investigate the adsorption behaviors of perfluorooctanoic acid (PFOA) on aged MPs (polystyrene, polyethylene, and polyethylene terephthalate) treated with UV irradiation and persulfate oxidation under salinity and dissolve organic matter (DOM) condition. Carbonyl index values of MPs increased after the aged treatment, indicating the production of oxygen‐containing groups. The PFOA adsorption on aged MPs was impacted by the co‐existence of Na+ ions and DOM. As PFOA adsorption onto aged MPs was mainly controlled by hydrophobic interaction, the electrostatic interaction also made a contribution, but there was no significant change in PFOA adsorption behavior between the pristine and aged MPs. While these findings provide insight into PFAS adsorption on aged MPs, further research is necessary to account for the complexity of the real environment. Practitioner Points: Adsorption behaviors of perfluorooctanoic acid (PFOA) on aged microplastics were investigated.Hydrophobic interaction mainly controlled PFOA adsorption on aged microplastics (MPs).Co‐existence dissolve organic matter and salinity influenced PFOA adsorption behaviors on aged MPs. [ABSTRACT FROM AUTHOR]

A method has been developed to quantify PET and PBT microplastics (MPs) based on depolymerization and detection of depolymerization products by gas chromatography-tandem mass spectrometry (GC–MS/MS) without a complex separation process from environmental samples. Under the optimal depolymerization conditions, PET and PBT were efficiently converted to ethylene glycol (78%) and 1,4-butanediol (87%), respectively. Subsequently, the linear curves were constructed between signal intensities of depolymerization products and polymer masses by GC–MS/MS, and the correlation coefficients of PET and PBT were 0.996 and 0.997, respectively. The spiking and recovery experiments of PET and PBT in the environmental samples showed that the recovery was stable in the range 89–100%, and the limit of detection was 4.95 μg and 1.39 μg of PET and PBT, respectively. The method has been proven to be capable of simultaneous identification and quantification of PBT and PET MPs in real environmental water samples without complex separation process, which provided a scheme for the determination of microplastics. [ABSTRACT FROM AUTHOR]

Microplastics, an emerging contaminant, are widespread in oceans around the world, and rivers are the key conveyors of these pollutants into the oceans. There exists a dearth of available data pertaining to seasonal fluctuation, spatial distribution and risk assessment of microplastics in rivers extending from upper reaches to the lower reaches. The collection of such data is of utmost importance for the purpose of formulating beneficial management strategies for riverine microplastics. In order to bridge this research gap, an investigation was made in the Periyar River in Kerala, India, which is exposed to anthropogenic stress and is at risk of microplastic pollution. A total of eighteen sites (six sites each from downstream, midstream and upstream) along the 244 km of the river were investigated across three seasons in a year. The study revealed a discernible pattern in the spatial distribution of microplastic concentrations, wherein there was a rise in abundance from the upstream to midstream and then a sudden increase of abundance along the downstream regions towards the lower reaches. The highest mean microplastic abundance of 124.95 items/L was obtained during the monsoon season followed by post-monsoon season i.e. 123.21 items/L and pre-monsoon i.e. 120.50 items/L. The predominant forms of microplastics were found to be fibres, fragments and filaments. Most prevalent polymer types acquired were polyethylene (PE) and polypropylene (PP). Pollution hazard index (PHI) and pollution load index (PLI) were also evaluated to assess the water quality of this river. The findings of this study conclude that the Periyar River is polluted with microplastics throughout its course and offer significant insights into the detection of microplastic origins in river systems and lend support to the implementation of potential measures aimed at mitigating their impact. [ABSTRACT FROM AUTHOR]

Microplastics pose significant challenges to ecosystems and organisms. They can be ingested by marine and terrestrial species, leading to potential health risks and ecological disruptions. This study aims to address the urgent need for effective remediation strategies by focusing on the biodegradation of microplastics, specifically polyvinyl chloride (PVC) derivatives, using the bacterial strain Bacillus albus. The study provides a comprehensive background on the accumulation of noxious substances in the environment and the importance of harnessing biodegradation as an eco-friendly method for pollutant elimination. The specific objective is to investigate the enzymatic capabilities of Bacillus albus, particularly the alpha/beta hydrolases (ABH), in degrading microplastics. To achieve this, in-silico studies were conducted, including analysis of the ABH protein sequence and its interaction with potential inhibitors targeting PVC derivatives. Docking scores of − 7.2 kcal/mol were obtained to evaluate the efficacy of the interactions. The study demonstrates the promising bioremediation prospects of Bacillus albus for microplastics, highlighting its potential as a key player in addressing microplastic pollution. The findings underscore the urgent need for further experimental validation and practical implementation of Bacillus albus in environmental remediation strategies. [ABSTRACT FROM AUTHOR]

High levels of plastic pollutants threaten aquatic habitats as the plastic materials are ingested by aquatic organisms as food. This study assessed seasonal variations of microplastics and the water quality of Njoro River and Lake Nakuru. Selected water physico-chemical parameters were measured. Microplastic abundance in the surface water samples in the dry season was recorded as 47–649 MPs 300L−1 for sampling points in Njoro River and 54–508 microplastics (MPs) 300L−1 for Fisher’s Point in Lake Nakuru; an abundance during the rainy season was measured as 8–389 MPs 300L−1 and 28–259 MPs 300L−1 for Njoro River and Lake Nakuru, respectively. Our study observed a significant pattern of microplastics from polymers such as polyethylene (20%), polypropylene (25%), polyester (40%) and polyethylene terephthalate (10%). Salinity ranged between 0.085 to 2.59 ± 0.03 ppt; temperature 23.69–14.22 ± 0.07°C; pH 8.8–9.3; turbidity 13.95−36.03 ± 0.35 NTU; TN 5.9 to 8.57 ± 3.24 mg L−1; TP 7.49−.41 ± 1.84 mg L−1; EC 73.3−533.3 ± 0.64 μs cm−1; and TDS 46.67–243.33 ± 0.11ppm. These ranges were within the standards recommended by WHO and US EPA. Results indicate the possibility for the quantity and mass of plastic particles in Lake Nakuru to surpass that of Njoro River. [ABSTRACT FROM AUTHOR]

Background: Plastic is generating global pollution and the replacement such as bioplastic has been developed to mitigate the pollution. To this end, the fate, transformation and pathway of bioplastics need more research. For example, the fragmentation of bioplastic can release small debris that can be categorised as microplastics, which is tested herein by taking an example of a compostable plastic that is used as a bin bag on our kitchen table to collect the food residues. Results: First, we employ matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) to identify the main components of the bioplastic bag as polymer and starch. Next, we use Raman imaging to monitor the stability under laser illumination, in an oven at ~ 60 °C for ~ 2 weeks, or in the presence of tap water for half a year. Basically, the compostable plastic is stable under these conditions. Thirdly, however, once used as table-bin bag with involvement of food residues, within ~ 1 week, the bioplastic bag is broken and biodegraded to release debris. The derivate surface groups are effectively monitored and directly visualised via Raman imaging, and cross-checked with scanning electron microscope (SEM). The yielded small molecule such as formic acid is also identified, along with the released debris of microplastics, with the help of on-site extraction of the fragmented sample and imaging analysis algorithm of the hyper spectrum. Conclusions: After one week, the bag in the waste bin fragments, releasing a significant amount of debris. This could pose a functional issue if users intend to use the bag for at least a week, and could become a potential environmental problem if the waste is dispersed uncontrollably. In general, further research is needed to potentially distinguish the persistent conventional microplastics from the bioplastic fragments, to effectively mitigate the plastic pollution. [ABSTRACT FROM AUTHOR]

Plastics are extensively used in agriculture, but their weathering and degradation generates microplastics (MPs) that can be carried by runoff into water bodies where they can accumulate and impact wildlife. Due to its physicochemical properties, biochar has shown promise in mitigating contaminants in agricultural runoff. However, few studies have examined its effectiveness at removing MPs. In this study, we assessed MP pollution (>30 µm) in runoff from a farm in the Mississippi Delta and examined the effectiveness of biochar (pinewood and sugarcane) to remove MPs from aqueous solutions. Using micro-Fourier Transform Infrared spectroscopy (µ-FTIR), we observed an average of 237 MPs/L (range 27-609) in the runoff, with most particles identified as polyethylene, polyamide, polyvinyl chloride, polyurethane, acrylonitrile butadiene styrene, and polyarylamide. Biochar columns effectively removed MPs from runoff samples with reductions ranging from 86.6% to 92.6%. MPs of different sizes, shapes, and types were stained with Nile red dye (to facilitate observation by fluorescence) and quantified their downward progress with multiple column volumes of water and wet/dry cycles. Smaller MPs penetrated the columns further, but ≥90% of MPs were retained in the ~20 cm columns regardless of their shape, size, and type. We attribute these results to physical entrapment, hydrophobic behaviors, and electrostatic interactions. Overall, this proof-of-concept work suggests biochar may serve as a cost-effective approach to remove MPs from runoff, and that subsequent field studies are warranted. [ABSTRACT FROM AUTHOR]

This data paper presents microplastic (MP) concentration and composition data from four campaigns in a one-year period in the Seine River within the Greater Paris area. Detailed data on MP occurrence, physical water parameters, hydrological conditions, and potential sewer point sources are presented. Initial analysis of the data set shows that MP concentrations were significant (median: 600 particles m-3 and 100 mg m-3) and MP fluxes showed variations across sampling sites and campaigns. Three polymer types (polypropylene -- PP, polyethylene -- PE, polystyrene -- PS) account for 96% of the total number of MP. This dataset provides valuable insights for understanding river MP pollution under anthropogenic pressure. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are gaining global attention in recent years due to its widespread distribution and potential health impacts. The present study focuses on the distribution and characterisation of microplastics in the sediments and its transfer into the organisms living in Kavvayi and Kumbla backwaters of Northern Malabar region, Kerala, India. MP isolation procedures including density separation, organic matter digestion, and membrane filtration followed by visual and spectral analyses using optical microscope and confocal Raman spectroscopy have been utilised for the microplastic evaluation. Microplastics of size range up to 1 μm was analysed, and the presence of MPs was detected in all samples with an average abundance of 99.5 ± 69.43 particles/kg and 96.57 ± 29.96 particles/kg in Kavvayi and Kumbla backwaters respectively. Raman spectral analysis confirmed that almost 50% of MPs to be synthetic elastomers with the remaining half encompassed by polyamide, polyethylene, polyester, polyurethane, and polypropylene. Higher abundance of MPs in the edible aquatic organisms like clams, prawns, and fishes confirmed the transfer of MP from the environment into living organisms envisages the need of further investigation on toxicological impacts and management strategies. [ABSTRACT FROM AUTHOR]

Contamination with plastics of small dimensions (<1 µm) represents a health concern for many terrestrial and aquatic organisms. This study examined the use of plastic-binding peptides as a coating probe to detect various types of plastic using a plasmon nano-gold sensor. Plastic-binding peptides were selected for polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS) based on the reported literature. Using nAu with each of these peptides to test the target plastics revealed high signal, at 525/630 nm, suggesting that the target plastic limited HCl-induced nAu aggregation. Testing with other plastics revealed some lack of specificity but the signal was always lower than that of the target plastic. This suggests that these peptides, although reacting mainly with their target plastic, show partial reactivity with the other target plastics. By using a multiple regression model, the relative levels of a given plastic could be corrected by the presence of other plastics. This approach was tested in freshwater mussels caged for 3 months at sites suspected to release plastic materials: in rainfall overflow discharges, downstream a largely populated city, and in a municipal effluent dispersion plume. The data revealed that the digestive glands of the mussels contained higher levels of PP, PE, and PET plastic particles at the rainfall overflow and downstream city sites compared to the treated municipal effluent site. This corroborated earlier findings that wastewater treatment could remove nanoparticles, at least in part. A quick and inexpensive screening test for plastic nanoparticles in biological samples with plasmonic nAu-peptides is proposed. [ABSTRACT FROM AUTHOR]

Microplastic has emerged as a global threat owing to its chronic ubiquity and persistence. Microplastics' small size expedites their ingestion at each trophic level causing biomagnification and bioaccumulation, which has raised public concerns. The present study isolated, quantified and characterized the abundance, shape, size, color, and chemical composition of the microplastics from water and sediments of the Hirakud Reservoir through a scanning electron microscope and FTIR. The ecological risk associated with the microplastics was assessed using the species sensitivity distribution (SSD) method to derive the Predicted No-Effect Concentration (PNEC) value and risk quotient (RQ). The abundance of microplastics in the surface water and sediments of the Hirakud Reservoir was estimated at 82-89 particles/L and 159-163 particles/kg, respectively. Fiber-shaped microplastics dominated both surface water (46.21%) and sediment samples (44.86%). Small-sized microplastics (53-300 μm) prevailed in all samples. Color delineation exhibited an abundance of transparent microplastics. Chemical characterization indicated the dominance of polypropylene (38%), followed by high-density polyethylene, low-density polyethylene, and polystyrene. The calculated PNEC value was 3,954 particles/m³, and the RQ was estimated to be 0.02073-0.04122 indicating negligible ecological risk to freshwater species in all the sampling sites. [ABSTRACT FROM AUTHOR]

Plastic pollution is becoming a major health issue due to the recent discovery of microplastics and nanoplastics in living organisms and the environment, calling for advanced technologies to remove plastic waste. Here we review enzymes that degrade plastics with focus on plastic properties, protein engineering and polymers such as poly(ethylene terephthalate), poly(butylene adipate-co-terephthalate), poly(lactic acid), polyamide and polyurethane. The mechanism of action of natural and engineered enzymes has been probed by experimental and computation approaches. The performance of polyester-degrading enzymes has been improved via directed evolution, structure-guided rational design and machine learning-aided strategies. The improved enzymes display higher stability at elevated temperatures, and tailored substrate-binding sites. [ABSTRACT FROM AUTHOR]

The global plastic production has steadily increased from 1.7 million tons in 1950 to over 400 million tons in 2022, with about 60% of plastic ultimately ending up in landfills and oceans. There is also growing evidence that microplastics exert negative effects on biota and ecosystems. Biodegradable plastics may represent a safe alternative, yet their potential adverse effects have not been comprehensively analyzed. Here, we reviewed biodegradable plastics, with focus on their conversion into microplastics, their interactions with pollutants, and their combined toxicity for aquatic biota. Biodegradable plastics include polylactic acid, polyhydroxyalkanoates, polybutylene succinate, poly(butylene adipate-co-terephthalate), and poly(ε-caprolactone). We found that some biobased plastics are hardly biodegradable. Some biobased plastics are compostable but require specific environmental conditions for their biodegradation. Biobased plastics can generate microplastics when released into the environment, which can impact biota. Contrary to the common public belief, biodegradable plastics may not only originate from biosources but can be synthesized from fossil fuels. Microplastics originating from biodegradable plastics can interact with pollutants, adsorbing and transporting these pollutants, resulting in synergistic or antagonistic effects on exposed organisms. Biofilm formation on microplastics impacts their degradation and pollutant interactions. [ABSTRACT FROM AUTHOR]

Background: Escalating global plastic production, expected to reach 34,000 million tons by 2050, poses a significant threat to human and environmental well-being, particularly in aquatic ecosystems. Microplastics (MP) and nanoplastics (NP), which originate from the degradation of plastics, are of concern due to their potential bioaccumulation and uptake of pollutants. This study addresses identification methods and focuses on insect meal, a raw material for aquaculture feed. Methods: By using different techniques, the study was able to detect MP and NP in insect meal samples. Chemical digestion with KOH at 60 °C efficiently removed organic matter without affecting the synthetic polymer polyethylene (PE). Filtration, confocal Raman microscopy, SEM, and TEM were used for comprehensive analysis, and integrity tests on PE films were performed using Raman and FTIR spectroscopy. The results showed the presence of PE microplastic particles in the insect meal, which was confirmed by correlative Raman and SEM mapping on a positively charged surface. In addition, the increased resolution of the Raman microscope identified submicrometric PE NP (800 nm). Transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDX) confirmed plastic-like structures in the insect meal, highlighting the presence of PE plastics characterized by irregular shapes and some agglomeration. The higher carbon concentration in the EDX analysis supported the plastic nature, which was also confirmed by Raman spectroscopy. Conclusions: The study provides a robust method for the detection of MP and NP in insect meal and provides valuable insight into the possible presence of plastics in insect-based aquafeeds. The combination of different analytical methods increases the reliability of the results and sets the stage for future investigations that could focus on the quantification of NP and the assessment of their potential environmental impact. [ABSTRACT FROM AUTHOR]

Plastic is a widely available material in every aspect of life, and its long‐term usage is an important threat to the environment. An enormous quantity of plastic waste has been discharged into the environment throughout the world, resulting in global white pollution. The weathering of accumulated plastic waste in the environment, which can further break down into small fragments like microplastics and nanoplastics, will harm the ecosystem and humans. Therefore, the production and disposal of plastics need to be considered. Bioplastics are increasingly being used as an alternative to conventional plastics; their primary purpose is to solve pollution‐related problems with plastics. Bioplastics (BPs) are an adequate substitute for traditional plastics since they have less carbon footprint and are readily biodegradable, but not all bioplastics can degrade entirely in the natural environment. Due to less environmental impact, bioplastics are defined as polymers produced by using renewable feedstocks or by microorganisms. BP has a wide range of applications in the medical, automotive, and food packaging industries, and it has the potential impact on effect of development of low‐carbon environment. The standards bioplastics must meet to be called compostable or biodegradable are determined by certified worldwide standard processes. The primary purpose of this review is to focus on bioplastics as an alternative tool to plastic—its types, structure, characteristics, degradation behavior, standard techniques, feedstock used for the production of bioplastic, process for its development, and limitation of bioplastics. [ABSTRACT FROM AUTHOR]

Packaging has important functions for products, contributing to their protection and presenting information. Recognizing that food loss and waste affect all countries, it is necessary to search for alternatives that change this scenario, such as active packaging. Particles with sizes between 1 and 100 nanometers (nanoparticles) are incorporated into polymeric materials because they are capable of improving or even providing properties that the film formed by the pure polymer does not have, due to its surface area being greater than that of macro‐sized particles. If two nanoparticles are previously combined to form a nanohybrid before being dispersed in a polymeric matrix, in addition to having this purpose, they can provide even better results when incorporated, due to the synergistic effects that can be attributed to the nanoparticles used. The utilization of active packaging composed of nano‐hybrids within biodegradable polymers holds significant potential for reducing solid plastic waste and the generation of persistent microplastics, thereby positively impacting human health. In this literature review, the effects of nanohybrid on antibacterial and barrier properties for application in food packaging in polymeric matrices were investigated using materials such as: nickel nanoparticles, zinc oxide nanoparticles, silver nanoparticles, copper oxide nanoparticles, cellulose nanowhiskers, Cloisite 30B, sodium alginate, poly(ethylene oxide), starch, poly(vinyl alcohol), chitosan and gelatin. The results were found to show the efficiency of nanohybrids in polymeric matrices, decreasing the water vapor and oxygen permeability and also increasing the antibacterial activity, which can prevent illnesses stemming from contaminated food occurs. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive review on microplastic from source to sink and reviews the current state of knowledge of the topic by focusing on the articles published within the last five years on identification, quantification, analyses, and effects of microplastics on soil and aqueous environments. Microplastics are materials formed either by the degradation of the plastic into smaller micro sized particles or obtained directly in daily products such as cosmetics, toothpastes, domestic cleaning products, etc. Hence, the origin of microplastics is either a primary or secondary microplastic source. The lack of information and research conducted on microplastics in soil compared to water influenced many disparities. These include variations in defining microplastics to lack of conclusive methodologies in analysis of microplastics in soil which therefore lead to gaps in identification of plastic source and comprehension of plastic pollution in soil. The effect of microplastics on different aquatic vertebrates, mammals, and humans is studied and, in most cases, various negative effects were observed in the organism's physiology. In addition to innovative control methods, there is a growing focus on exploring bioplastics as a potential substitute for traditional plastics. Numerous studies suggest that the environmental impact is more manageable with the production and use of bioplastics. Nonetheless, additional research is needed to confirm the viability of bioplastics as a potential solution. [ABSTRACT FROM AUTHOR]

Microplastic pollution is a pervasive global issue affecting various ecosystems. Despite the escalating production and well-documented contamination in both aquatic and terrestrial environments, the research focused on airborne microplastics and their interaction with terrestrial birds remains limited. In this study, we collected fecal sacs from Common swifts (Apus apus) to investigate their diet and to evaluate the potential ingestion of microplastics by both adults and nestlings. The diet was mainly composed of Hymenoptera and Coleoptera and did not differ among sexes and age classes. The 33% of nestlings' and 52% of adults' fecal sacs contained anthropogenic items, the totality of which was in the shape form of fibers. The 19.4% of the anthropogenic items were chemically characterized as microplastics, either polyethylene terephthalate (PET; two microfibers) or cellophane (four microfibers). Airborne anthropogenic items, including microplastic, might be passively ingested during the Common swift aerial feeding. In addition, our findings suggest that these ingested microparticles have the potential to be transferred to the offspring through food. While further research is essential to elucidate the pathways of microplastic ingestion, our results reinforce the evidence of the transfer of anthropogenic items from the atmosphere to the biota. [ABSTRACT FROM AUTHOR]

Detecting, separating, and characterizing airborne microplastics from other airborne particulates is currently challenging due to the various instrumental constraints and related sample preparation hurdles that must be overcome. The ability to measure these real-world environments is needed to better assess the risks associated with microplastics. To that end, the current study focused on developing a methodology for sampling and characterizing airborne microplastics. Particulate sampling was carried out at a municipal materials recovery facility near a conveyer belt containing sorted plastic materials to collect airborne environmental particles on filters. Nucleopore filters were mounted on Teflon support rings, coated with 100 nm aluminum to reduce the background signal for micro-Raman spectroscopy, and marked with a fiducial pattern using a laser engraver. The fiducial pattern was crucial in identifying samples, relocating particles, and efficiently enabling orthogonal measurements on the same samples. Optimum sampling conditions of 2 h at 25 L/min were determined using light microscopy to evaluate the particle loadings. The filters were then cut into slices which were attached to sections of thin beryllium-copper sheeting for easy transfer of the filter between microscopy platforms. Scanning electron microscopy was used to identify carbon-rich particles. Light microscopy was used to identify colored particles which were also carbon-rich which were then analyzed using micro-Raman spectroscopy to identify specific polymers. [ABSTRACT FROM AUTHOR]

Approximately 50% of global plastic wastes are produced from plastic packaging, a substantial amount of which is disposed of within a few minutes of its use. Although many plastic types are designed for single use, they are not always disposable. It is now widely acknowledged that the production and disposal of plastics have led to a plethora of negative consequences, including the contamination of both groundwater and soil resources and the deterioration of human health. The undeniable impact of excessive plastic manufacturing and waste generation on the global plastic pollution crisis has been well documented. Therefore, degradable polymers are a crucial solution to the problem of the non-degradation of plastic wastes. The disadvantage of degradable polymers is their high cost, so blending them with natural polymers will reduce the cost of final products and maximize their degradation rate, making degradable polymers competitive with industrial polymers that are currently in use daily. In this work, we will delineate various degradable polymers, including polycaprolactone, starch, and cellulose. Furthermore, we will elucidate several aspects of polyvinyl alcohol (PVA) and its blends with natural polymers to show the effects of adding natural polymers on PVA properties. This paper will study cost-effective and ecologically acceptable polymers by combining inexpensive natural polymers with readily accessible biodegradable polymers such as polyvinyl alcohol (PVA). [ABSTRACT FROM AUTHOR]

Microbeads find widespread usage in personal care items and cosmetics, serving as exfoliants or scrubbing agents. Their micro-scale size poses challenges in effective drainage capture and given their origin from non-biodegradable oil-based plastics, this contributes substantially to marine pollution. In this study, microbeads were prepared by a simple yet scalable melt homogenization method using four types of polyhydroxyalkanoates (PHA), namely poly[(R)-3-hydroxybutyrate] (P(3HB)), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyvalerate] (P(3HB-co-3HV)), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] (P(3HB-co-3HHx)) and poly[(R)-3-hydroxybutyrate-co-(R)-4-hydroxyvalerate] (P(3HB-co-4HB)). Microbeads with different surface smoothness, compressive strength (6.2–13.3 MPa) and diameter (from 1 ~ 150 μm) could be produced. The microbeads were subjected to a comprehensive degradation analysis using three techniques: enzymatic, Biochemical Oxygen Demand (BOD) evaluations, and in situ degradation tests in the deep-sea off Misaki Port in the northern Pacific Ocean (depth of 757 m). Qualitatively, results from enzymatic and in situ degradation demonstrated significant degradation within one week and five months, respectively. Quantitatively, BOD findings indicated that all PHA microbeads degraded similarly to cellulose (~ 85% biodegradability in 25 days). In conclusion, PHA microbeads from this study exhibit promising potential as alternatives to conventional non-biodegradable microbeads. [ABSTRACT FROM AUTHOR]

The topic of riverine microplastics is of great interest to the general public, yet the univocal scientific knowledge on this topic is limited. This review investigated the occurrence of microplastics in 6 major European rivers and their tributaries based on the results from 29 studies. We examined the reviewed studies in regard to data quality and reproducibility and assessed the abundance of microplastics in different sections of the water column. Furthermore, we investigated the chemical composition and potential origin of the reported riverine microplastics. We found that polystyrene, polypropylene, and polyethylene were the most abundant polymer types. The majority of primary microplastics arose from the industry sector as well as from personal care and cleaning products, whereas secondary microplastics constituted fibers from synthetic textiles and fragments of diverse origins. We highlighted the diversity of experimental and analytical approaches that could lead to high uncertainties in the measurements of microplastics abundance. Furthermore, the presence of microplastics in rivers was found to vary spatially likely due to point and nonpoint pollution sources of anthropogenic activities. Heterogenous environmental processes impacted the fate of microplastics characterized by various forms, sizes, and densities, in different ways. This impeded the identification of representative quantitative measurements of microplastics across different time frames. We advocate for the development of standardized protocols by the research community to ensure higher reproducibility of sampling, processing, and analysis of microplastics in aquatic environments. We recommend long‐term and site‐specific monitoring on microplastics with high data comparability to better inform policy making. This article is categorized under:Science of Water > Water QualityWater and Life > Conservation, Management, and Awareness [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrophobic ZIF-8/SA monolithic materials were fabricated via in situ synthesis. • The cooperation of SA, PDMS, and ZIF-8 significantly enhanced adsorption capacity. • The composites displayed rapid kinetic adsorption. • The composites have remarkable absorption recyclability. Microplastics (MPs), a newly emerging class of environmental contaminants, pose a severe threat to the entire ecosystem. The development of efficient and environmentally responsible adsorbents for removing the MPs is a particularly urgent research. Herein, a kind of monolithic ZIF-8 based adsorbents featuring stable hydrophobicity and micropore-mesopore-macropore hierarchical porous structure were fabricated by in situ growth of ZIF-8 nanoparticles on sodium alginate (SA) framework, and using polydimethylsiloxane (PDMS) as a hydrophobic agent. The monolithic nature of ZIF-8/SA allowed an easy solid–liquid separation process for adsorbents from water environment compared to powdered materials. The hierarchical porous structure ensures a remarkable MPs removal performance. The ZIF-8/SA showed high adsorption capacities of 594, 585, and 282 mg/g for polymethyl methacrylate (PMMA), poly (vinylidene difluoride) (PVDF), and polyvinyl chloride (PVC) respectively, and rapid adsorption kinetic progress within 120 min. The ZIF-8/SA adsorbents also exhibited excellent stability in the presence of interfering ions, acid/alkali, and humic acid, and displayed adsorption performance of > 70 % even in actual aquatic environment such as tap water, river water, and seawater. The results of characterizations showed that the synergistic effect of electrostatic interaction, hydrogen bonding, hydrophobic force, and van der Waals force was the main adsorption mechanism. The well-designed hydrophobic ZIF-8/SA monolithic materials would be promising to rapidly remove the MPs from the water environment. [ABSTRACT FROM AUTHOR]

The ubiquitous proximity of the commonly used microplastic (MP) particles particularly polyethylene (PE), polypropylene (PP), and polystyrene (PS) poses a serious threat to the environment and human health globally. Biological treatment as an environment-friendly approach to counter MP pollution has recent interest when the bio-agent has beneficial functions in their ecosystem. This study aimed to utilize beneficial floc-forming bacteria Bacillus cereus SHBF2 isolated from an aquaculture farm in reducing the MP particles (PE, PP, and PS) from their environment. The bacteria were inoculated for 60 days in a medium containing MP particle as a sole carbon source. On different days of incubation (DOI), the bacterial growth analysis was monitored and the MP particles were harvested to examine their weight loss, surface changes, and alterations in chemical properties. After 60 DOI, the highest weight loss was recorded for PE, 6.87 ± 0.92%, which was further evaluated to daily reduction rate (k), 0.00118 day−1, and half-life (t1/2), 605.08 ± 138.52 days. The OD value (1.74 ± 0.008 Abs.) indicated the higher efficiency of bacteria for PP utilization, and so for the colony formation per define volume (1.04 × 1011 CFU/mL). Biofilm formation, erosions, cracks, and fragments were evident during the observation of the tested MPs using the scanning electron microscope (SEM). The formation of carbonyl and alcohol group due to the oxidation and hydrolysis by SHBF2 strain were confirmed using the Fourier transform infrared spectroscopic (FTIR) analysis. Additionally, the alterations of pH and CO2 evolution from each of the MP type ensures the bacterial activity and mineralization of the MP particles. The findings of this study have confirmed and indicated a higher degree of biodegradation for all of the selected MP particles. B. cereus SHBF2, the floc-forming bacteria used in aquaculture, has demonstrated a great potential for use as an efficient MP-degrading bacterium in the biofloc farming system in the near future to guarantee a sustainable green aquaculture production. [ABSTRACT FROM AUTHOR]

Sustainable poly (vinyl alcohol)/Agave fiber-based films were obtained by the melt mixing process. The structural features of films containing unmodified and modified Agave fibers after 90 days of composting were studied. The results indicated that more than 10% of the dry weight of films remained after composting. Thus, the weight loss differences in the material were attributed to a partial disintegration process instead of complete biodegradation or mineralization. The SEM analysis showed degraded fibers in the matrix, which left hollow areas that promoted film fragmentation. Regardless of the fiber type, all films showed a decrease in lignocellulosic components (waxes, pectin, hemicellulose) and crystallinity, as FTIR, TGA and XRD analysis indicated. Furthermore, DMA analysis corroborated that after 90 days, the chain motion of the main PVA chain (alpha transition) decreased due to the plasticizer exudation. Meanwhile, an increased movement of side chains (beta transition) was observed, indicating that more amorphous regions are available for degradation. The results could be of interest to packaging industries that develop biodegradable materials since these findings showed that the Agave fibers waste disintegrated faster than the polymeric PVA matrix, which led to obtaining microplastics instead of the total disintegration of the film. [ABSTRACT FROM AUTHOR]

Plastics that pollute the environment can be depleted to produce small plastic particles called microplastics. Microplastics have a wide range of negative effects on ecosystem health because they can enter food webs. This study has aimed to assess the ability of a consortium of bacteria colonizing plastic waste from Jakarta Bay to degrade polypropylene microplastics. The plastic waste was collected from 3 sampling points (Muara Kamal, Muara Angke, and Marina) and was enriched in the medium Zobell marine broth for 3d at 27 ˚C, at 125 rpm in an incubator shaker. The obtained bacterial consortium was then tested for their degrading activity on 0.2% polyethylene (PP) microplastics using Mineral Salt Medium (4.5 g/L K2HPO4, 0.2 g/L MgSO4.7H2O, 0.1 g/L CaCl2, 0.1 g/L NaCl, 0.002 g/L FeCl3, 0.1 g/L (NH4)2SO4) at 27 ˚C, 125 rpm for 60d. The results showed that the bacterial consortium degraded PP microplastic in the range of 2.16–6.6% (dry weight basis). Among the three sampling points, the bacterial consortium from Muara Angke exhibited the highest degradation activity. Damage to PP microplastics resulting from the bacterial degradation tests was confirmed using Fourier Transform Infra-Red (FTIR) and Scanning Electron Microscopy (SEM) analyses, which showed the damage to the chemical bonds and the surface of the microplastic. These findings suggest that the Muara Angke bacterial consortium is a viable candidate for PP microplastic remediation while posing no risk to human health or the environment. [ABSTRACT FROM AUTHOR]

The presence of plastic particles in oceans has been recognized as a major environmental concern. The decrease in particle size increases their ability to directly interact with biota, with particles in the nanometer size range (nanoplastics—NPs) displaying a higher ability to penetrate biological membranes, which increases with the decrease in particle size. This study aimed to evaluate the role of life stages in the effects of poly(methyl)methacrylate (PMMA) NPs on the polychaete Hediste diversicolor, a key species in the marine food web and nutrient cycle. Thus, behavioral (burrowing activity in clean and spiked sediment) and biochemical endpoints (neurotransmission, energy reserves, antioxidant defenses, and oxidative damage) were assessed in juvenile and adult organisms after 10 days of exposure to spiked sediment (between 0.5 and 128 mg PMMA NPs/Kg sediment). Overall, the results show that H. diversicolor is sensitive to the presence of PMMA NPs. In juveniles, exposed organisms took longer to burrow in sediment, with significant differences from the controls being observed at all tested concentrations when the test was performed with clean sediment, whereas in PMMA NP-spiked sediment, effects were only found at the concentrations 8, 32, and 128 mg PMMA NPs/Kg sediment. Adults displayed lower sensitivity, with differences to controls being found, for both sediment types, at 8, 32, and 128 mg PMMA NPs/Kg sediment. In terms of Acetylcholinesterase, used as a marker of effects on neurotransmission, juveniles and adults displayed opposite trends, with exposed juveniles displaying increased activity (suggesting apoptosis), whereas in adults, overall decreased activity was found. Energy-related parameters revealed a generally similar pattern (increase in exposed organisms) and higher sensitivity in juveniles (significant effects even at the lower concentrations). NPs also demonstrated the ability to increase antioxidant defenses (higher in juveniles), with oxidative damage only being found in terms of protein carbonylation (all tested NPs conditions) in juveniles. Overall, the data reveal the potential of PMMA NPs to affect behavior and induce toxic effects in H. diversicolor, with greater effects in juveniles. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the sustainable use of recycled plastics, specifically polypropylene (PP) and high-density polyethylene (HDPE), in the manufacture of geogrids for geotechnical and civil engineering applications. Plastics were collected from a recycling center, specifically targeting containers used for food, cleaning products, and other domestic packaging items. These plastics were sorted according to the Möbius triangle classification system, with HDPE (#2) and PP (#5) being the primary categories of interest. The research methodologically evaluates the mechanical properties of PP/HDPE (0/100, 25/75, 50/50, 75/25 and 100/0% w/w) composites through tensile and flexural tests, exploring various compositions and configurations of geogrids. The results highlight the superiority of pure recycled HDPE processed into 1.3 mm thick laminated yarns and hot air welded for 20 to 30 s, exhibiting a deformation exceeding 60% in comparison to the PP/HDPE composites. Through SolidWorks® Simulation, it was shown that the adoption of a trigonal geogrid geometry optimizes force distribution and tensile strength, significantly improving slope stabilization efficiency. Based on the results obtained, a laboratory-scale prototype geogrid was developed using an extrusion process. The results underscore the importance of careful composite design and yarn configuration selection to achieve the desired mechanical properties and performance in geogrid applications. It emphasizes the potential of recycled plastics as a viable and environmentally friendly solution for stabilizing slopes, contributing to the reduction in plastic waste and promoting sustainable construction practices. [ABSTRACT FROM AUTHOR]

The increased use of plastics in industrial and agricultural applications has led to high levels of pollution worldwide and is a significant challenge. To address this plastic pollution, conventional methods such as landfills and incineration are used, leading to further challenges such as the generation of greenhouse gas emissions. Therefore, increasing interest has been directed to identifying alternative methods to dispose of plastic waste from agriculture. The novelty of the current research arose from the lack of critical reviews on how 3-Dimensional (3D) printing was adopted for recycling plastics, its application in the production of agricultural plastics, and its specific benefits, disadvantages, and limitations in recycling plastics. The review paper offers novel insights regarding the application of 3D printing methods including Fused Particle Fabrication (FPF), Hot Melt Extrusion (HME), and Fused Deposition Modelling (FDM) to make filaments from plastics. However, the methods were adopted in local recycling setups where only small quantities of the raw materials were considered. Data was collected using a systematic review involving 39 studies. Findings showed that the application of the 3D printing methods led to the generation of agricultural plastics such as Polylactic Acid (PLA), Acrylonitrile Butadiene Styrene (ABS), Polyethylene Terephthalate (PET), and High-Density Polyethylene (HDPE), which were found to have properties comparable to those of virgin plastic, suggesting the viability of 3D printing in managing plastic pollution. However, limitations were also associated with the 3D printing methods; 3D-printed plastics deteriorated rapidly under Ultraviolet (UV) light and are non-biodegradable, posing further risks of plastic pollution. However, UV stabilization helps reduce plastic deterioration, thus increasing longevity and reducing disposal. Future directions emphasize identifying methods to reduce the deterioration of 3D-printed agricultural plastics and increasing their longevity in addition to UV stability. [ABSTRACT FROM AUTHOR]

Upon entering the environment, the surface properties of pristine plastics are rapidly altered due to interactions with exogenous biomolecules, contaminants, and even microbiota, which ultimately alter their ecological impacts. When present in biological fluids or high protein environments, micro(nano)plastics bind with proteins, which form a protein corona around the particle. Although a significant body of literature exists on protein corona formation on nanomaterials, less is known about how the physiochemical properties of microplastics may influence protein corona formation. This study utilises quantitative proteomics to quantify protein binding to pristine and leached microplastics. Pristine polyethylene (PE) beads (50 and 500 μm), polyamide (PA) fibres (100 μm), polyethylene terephthalate fibres (500 μm), and fragments (< 300 μm), as well as pristine and leached textile microfibres comprised of PET, recycled PET, PA or cotton were incubated for 24 h in bovine serum albumin solution (2 mg mL−1) to form a protein corona. Protein adsorption to microplastics was dependant on particle surface area to volume ratio but only when additives were absent. For environmentally relevant textile microfibres, cotton microfibres adsorbed significantly more protein than synthetic microfibres. Fourteen-day aqueous leaching increased the zeta potential of all microfibres. However, only PA fibres adsorbed significantly higher protein on the leached fibres compared to their pristine counterparts. Overall, the presence of chemical additives in microplastics strongly influenced protein corona formation, and this phenomenon should be incorporated into routine microplastic toxicity assessment. [ABSTRACT FROM AUTHOR]

Within the scope of the current study, the researchers developed activities for middle school students to raise their awareness on the harm of plastics and microplastics, which are detrimental to nature and living things. In addition, through the activities developed, the study aimed to provide students with knowledge of and experience with bioplastics, which have emerged as an alternative to plastic materials and are environmentally friendly. Twelve eighth grade students participated in the current study. The activities developed by the researchers within the framework of the REACT strategy covered a four-week period. The researchers made sure that the activities designed included each step of the REACT strategy (Relating, Experiencing, Applying, Cooperating, Transferring) and the researchers used different tools (mind map, concept map, Vee diagram). The study suggests that activities designed for classroom use should be integrated with tools such as Vee diagram, concept map and mind map in order to increase students' knowledge and awareness about global environmental problems as well as support students' ability to produce solutions to such problems. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) contamination is a well-established impact in oceans, but integrated approaches combining simultaneous analyzes of biotic and abiotic components are scarce. This study addresses this gap, demonstrating Atherinella brasiliensis (fish species) ingestion of MPs and comparing with the contaminant presence in water and sediment. Three Ubatuba beaches (exposed, calm and sheltered estuary) were surveyed for fish, water, and sediment components in summer and winter. Environmental data evidenced spatial and seasonal differences (PCA/ANOVA). Presence of synthetic particles (SPs) in fish was high (~38%). Maximum concentrations occurred in the estuary, for water (490 SPs/m³), and in the exposed beach, for sediment (62 SPs/50g). Fibers format predominated in all components. Fish preference for blue color seems to occur. Significant statistical relationships were determined for fish length and SPs size and between SPs concentrations in water and fish. The chemical identities (µ-FTIR spectra) polypropylene, polyethylene, polyamide, polyester, and cardboard/cellulose predominated. Influences of local hydrodynamics (e.g., SPs sizes) and reduction in tourism during Covid-19 epidemic (e.g., less SPs in summer) are discussed. This study confirms environmental contamination by SPs (mostly MPs) in Ubatuba beaches, affecting fish through direct water column ingestion. Urgent actions from authorities and changes in local user's habits are crucial. [ABSTRACT FROM AUTHOR]

Microplastics have garnered an infamous reputation as a sorbate for many concerning environmental pollutants and as a delivery vehicle for the aquatic food chain through the ingestion of these contaminated small particulates. While sorption mechanisms have been extensively studied for polycyclic aromatic hydrocarbons, polycyclic aromatic sulfur heterocycles (PASHs) have not been investigated, partly due to their low concentrations in aquatic ecosystems. Herein, an analytical methodology is presented for the analysis of dibenzothiophene, benzo[b]naphtho[1,2-b]thiophene, benzo[b]naphtho[2,1-b]thiophene, benzo[b]naphtho[2,3-b]thiophene, chryseno[4,5-bcd]thiophene and dinaphtho[1,2-b:1′,2′-d]thiophene at relevant environmental concentrations based on solid phase extraction and high-performance liquid chromatography. The sorption uptake behavior and the sorption kinetics of the three benzo[b]napthothiophene isomers were then investigated on nylon microplastics to provide original information on their environmental fate and avoid human contamination through the food chain. The obtained information might also prove relevant to the development of successful remediation approaches for aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Polyethylene-, polyvinylidene chloride-, and per- and polyfluoroalkyl substance-coated paper generate microplastics or fluorochemicals in the environment. Here, we report an approach for the development of oil-resistant papers using an environmentally friendly, fluorine-free, water-dispersible poly(dimethylsiloxane) (PDMS) coating on kraft paper. Carboxylic-functionalized PDMS (PDMS-COOH) was synthesized and subsequently neutralized with ammonium bicarbonate to obtain a waterborne emulsion, which was then coated onto kraft paper. The water resistance of the coated paper was determined via Cobb60 measurements. The Cobb60 value was reduced to 2.70 ± 0.14 g/m2 as compared to 87.6 ± 5.1 g/m2 for uncoated paper, suggesting a remarkable improvement in water resistance. Similarly, oil resistance was found to be 12/12 on the kit test scale versus 0/12 for uncoated paper. In addition, the coated paper retained 70–90% of its inherent mechanical properties, and more importantly, the coated paper was recycled via pulp recovery using a standard protocol with a 91.1% yield. [ABSTRACT FROM AUTHOR]

Frequently used protective items during the pandemics are prepared from plastics products, such as polypropylene, polyurethane, polyacrylonitrile, polystyrene, polycarbonate, polyethylene, and polyester. Globally more than 57 million pounds of personal protective equipment along with other biomedical plastic waste are entering into the oceans per annum. Lots of economic benefits can be obtained by recycling the polymeric wastes by converting them into useful products through, reduced manufacture cost, bio converted products, and cleaner environment by developing a circular waste management model. Personal protective equipment's are prepared from different plastic products and the outer most surface of these free-floating plastics presents in the aquatic environment serve as colonization support to diverse microbial populations known as plastisphere. Microbial colonization starts with an initial attachment under different environmental conditions, subsequently by developing a permanent association on the plastic surface. The community structure of microorganisms in the plastisphere can be significantly influenced by the depth of water in the aquatic ecosystem where microplastics present and the nutrients availability. As microorganisms have been deeply investigated for their role in the biodegradation of several pollutants, the present review article focuses on microbial diversity on plastisphere in the aquatic ecosystem, the underlying mechanism of colonization, and their potential role in microplastic degradation. This review article also highlights on imminent research for sustainable management of aquatic microplastic pollution. [ABSTRACT FROM AUTHOR]

This article explores the relationship between solar UV radiation, climate change, and plastic pollution. It highlights the role of UV-driven weathering in the degradation of plastics and the formation of harmful micro- and nanoplastic particles. The article emphasizes the need for global assessments of plastic dispersal, persistence, and weathering to consider these linkages. It also discusses the impact of the Montreal Protocol on plastic degradation and the potential effects of UV radiation and climate change on plastic pollution in the future. The article concludes by calling for further research and the development of new plastics with durability matching the functional life of products. [Extracted from the article]

This investigation explores the various impacts that polystyrene microplastics (PS-MPs) have on human health. As most of the plastic materials affect human health when they release leachable toxic substances that affect human health, this causes a negative effect that determines poor health conditions and leads to health hazards associated with plastic toxins routed in the human body, such as: Polychlorinated Biphenyls, Polybrominated Biphenyls etc. The study includes micro-plastic exposure assessment on testicular structure analysis, and cytotoxicity evaluations of different human cell types. The findings clarified the possible dangers of PS-MPs exposure from food, medications, and common products, emphasising the necessity of standard specimen handling procedures for precise biomonitoring. [ABSTRACT FROM AUTHOR]