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Microplastics and nanoplastics have become noteworthy contaminants, affecting not only outdoor ecosystems but also making a notable impact within indoor environments. The release of microplastics and nanoplastics from commonly used plastic items remains a concern, and the characterisation of these contaminants is still challenging. This study focused on evaluating the microplastics and nanoplastics produced from plastic building bricks. Using Raman spectroscopy and correlation analysis, the plastic material used to manufacture building blocks was determined to be either acrylonitrile butadiene styrene (correlation value of 0.77) or polycarbonate (correlation value of 0.96). A principal component analysis (PCA) algorithm was optimised for improved detection of the debris particles released. Some challenges in microplastic analysis, such as the interference from the colourants in the building block materials, was explored and discussed. Combining Raman results with scanning electron microscopy - energy-dispersive X-ray spectroscopy, we found the scratches on the building blocks to be a significant source of contamination, estimated several thousand microplastics and several hundred thousand nanoplastics were generated per mm2 following simulated play activities. The potential exposure to microplastics and nanoplastics during play poses risks associated with the ingestion and inhalation of these minute plastic particles. [Display omitted] • Interlocking and dismantling building bricks create microscopic scuffs. • Raman analysis confirms the presence of microplastics and nanoplastics. • Principal component analysis enables effective identification of polymer type. • The number of fragments released may represent a risk to children. [ABSTRACT FROM AUTHOR]

The Ganga is the largest river in India, serves as a lifeline for agriculture, drinking water, and religious rites. However, it became highly polluted due to the influx of industrial wastes and untreated sewages, leading to the decline of aquatic biodiversity. This study investigated the microbial diversity and plastic-xenobiotic degrading enzymes of six sediment metagenomes of river Ganga at Prayagraj (RDG, TSG, SDG) and Devprayag (KRG, BNG, BRG). The water quality parameters, higher values of BOD (1.8–3.7 ppm), COD (23–29.2 ppm) and organic carbon (0.18–0.51%) were recorded at Prayagraj. Comparative analysis of microbial community structure between Prayagraj and Devprayag revealed significant differences between Bacteroidetes and Firmicutes, which emerging as the predominant bacterial phyla across six sediment samples. Notably, their prevalence was highest in the BRG samples. Furthermore, 25 OTUs at genus level were consistent across all six samples. Alpha diversity exhibited minimal variation among samples, while beta diversity indicated an inverse relationship between species richness and diversity. Co-occurrence network analysis established that genera from the same and different groups of phyla show positive co-relations with each other. Thirteen plastic degrading enzymes, including Laccase, Alkane-1 monooxygenase and Alkane monooxygenase, were identified from six sediment metagenomes of river Ganga, which can degrade non-biodegradable plastic viz. Polyethylene, Polystyrene and Low-density Polyethelene. Further, 18 xenobiotic degradation enzymes were identified for the degradation of Bisphenol, Xylene, Toluene, Polycyclic aromatic hydrocarbon, Styrene, Atrazene and Dioxin etc. This is the first report on the identification of non-biodegradable plastic degrading enzymes from sediment metagenomes of river Ganga, India. The findings of this study would help in pollution abatement and sustainable management of riverine ecosystem. [Display omitted] • Metagenomic study of microbial communities in sediments of river Ganga stretches. • Highest concentrations of Mn, Fe, and Cr were observed in the polluted sites. • Bacteroidota and Chloroflexota were predominant in all sediment samples. • First report reveals the presence of 13 plastic & 18 xenobiotic degradation enzymes. [ABSTRACT FROM AUTHOR]

Concerns over worldwide plastic pollution have led to the development of biodegradable polyester materials with excellent physical and chemical properties through the copolymerization of poly(butylene oxalate) (PBOx). As a result, poly(butylene oxalate- co -terephthalate)s (PBOTs) with varying compositions, were prepared by incorporating aromatic units. Studies have indicated that PBOT-47 (with a 47% molar terephthalate), exhibits exceptional mechanical properties. With an elongation at break of 1160% and a tensile strength that remains above 30 MPa, similar to or even better than those of the commercial biodegradable plastic poly(butylene adipate- co -terephthalate) PBAT-47 (47% molar terephthalate). Moreover, the permeability coefficients of PBAT-47 for H 2 O, CO 2 and O 2 were 5.8, 50.6 and 5.6 times higher than that of PBOT-47, revealing the superior barrier properties of PBOT. Through experimental research and theoretical simulation, the mechanism of the copolymer hydrolysis was elucidated. The readily hydrolytic nature of the oxalate unit endows it with the capacity for rapid degradation, possessing the potential to be a short-term degradable material with physical properties similar to PBAT. [Display omitted] • PBOT balances degradation and physical properties toward PBAT-like material. • Unique non-enzymatic hydrolysis oxalate unit contributes to rapid hydrolysis. • Theoretical insights elucidate BOx unit's role in hydrolysis. • PBOT has lower cost than PBAT. [ABSTRACT FROM AUTHOR]

The accumulation of microplastics in reservoirs due to river damming has drawn considerable attention due to their potential impacts on elemental biogeochemical cycling at the watershed scale. However, the effects of plastisphere communities on the sulfur cycle in the large deep-water reservoir remain poorly understood. Here, we collected microplastics and their surrounding environmental samples in the water and sediment ecosystems of Xiaowan Reservoir and found a significant spatiotemporal pattern of microplastics and sulfur distribution in this Reservoir. Based on the microbial analysis, plastic-degrading taxa (e.g., Ralstonia , Rhodococcus) involved in the sulfur cycle were enriched in the plastisphere of water and sediment, respectively. Typical thiosulfate oxidizing bacteria Limnobacter acted as keystone species in the plastisphere microbial network. Sulfate, oxidation reduction potential and organic matter drove the variations of the plastisphere. Environmental filtration significantly affected the plastisphere communities, and the deterministic process dominated the community assembly. Furthermore, predicted functional profiles related to sulfur cycling, compound degradation and membrane transport were significantly enriched in the plastisphere. Overall, our results suggest microplastics as a new microbial niche exert different effects in water and sediment environments, and provide insights into the potential impacts of the plastisphere on the sulfur biogeochemical cycle in the reservoir ecosystem. [Display omitted] • Plastisphere has potential impacts on the sulfur cycling in the reservoir. • MPs selectively enriched plastic-degrading taxa with sulfur conversion function. • Keystone species in the plastisphere mainly mediated sulfur and carbon cycles. • Predicted functions between plastisphere and surrounding environment are different. [ABSTRACT FROM AUTHOR]

The microbial degradation of polyethylene (PE) and polypropylene (PP) resins in rivers and lakes has emerged as a crucial issue in the management of microplastics. This study revealed that as the flow rate decreased longitudinally, ammonia nitrogen (NH 4 +-N), heavy fraction of organic carbon (HFOC), and small-size microplastics (< 1 mm) gradually accumulated in the deep and downstream estuarine sediments. Based on their surface morphology and carbonyl index, these sediments were identified as the potential hot zone for PE/PP degradation. Within the identified hot zone, concentrations of PE/PP-degrading genes, enzymes, and bacteria were significantly elevated compared to other zones, exhibiting strong intercorrelations. Analysis of niche differences revealed that the accumulation of NH 4 +-N and HFOC in the hot zone facilitated the synergistic coexistence of key bacteria responsible for PE/PP degradation within biofilms. The findings of this study offer a novel insight and comprehensive understanding of the distribution characteristics and synergistic degradation potential of PE/PP in natural freshwater environments. [Display omitted] • Microplastic was enriched in freshwater estuarine sediments with reduced flow rate. • Deep and downstream sediment was the hot zone of PE/PP degradation in estuaries. • PE/PP-degrading genes and enzymes of plastic biofilms were higher in the hot zone. • PE/PP-degrading core bacteria and enzymes in biofilms were positively correlated. • NH 4 +-N and HFOC benefit the coexistence of synergistic-degrading bacteria of PE/PP. [ABSTRACT FROM AUTHOR]

Some narratives present biodegradable plastic use for soil mulching practices in agriculture as "environmentally friendly" and "sustainable" alternatives to conventional plastics. To verify these narratives, environmental research recently started focusing on their potential impact on soil health, highlighting some concerns. The paper by Degli-Innocenti criticizes this unfolding knowledge arguing that it is affected by communication hypes, alarmistic writing and a focus on exposure scenarios purposedly crafted to yield negative effects. The quest of scientists for increased impact – the paper concludes – is the driver of such behavior. As scholars devoted to the safeguarding of scientific integrity, we set to verify whether this serious claim is grounded in evidence. Through a bibliometric analysis (using number of paper reads, citations and mentions on social media to measure the impact of publications) we found that: i) the papers pointed out by Degli-Innocenti as examples of biased works do not score higher than the median of similar publications; ii) the methodology used to support the conclusion is non-scientific; and iii) the paper does not fulfil the requirements concerning disclosure of conflicts of interests. We conclude that this paper represents a non-scientific opinion, potentially biased by a conflict of interest. We ask the paper to be clearly tagged as such, after the necessary corrections on the ethic section have been made. That being said, the paper does offer some useful insights for the definition of exposure scenarios in risk assessment. We comment and elaborate on these proposed models, hoping that this can help to advance the field. • The paper main conclusion was assessed through bibliometric analysis. • No evidence that hypes in papers' titles results in high impact. • The incomplete disclosure of competing interests is reported. • Evidence of residues of biodegradable plastic films in soil is given. • The predicted environmental concentration model is critically discussed. [ABSTRACT FROM AUTHOR]

The escalating prevalence of nanoplastics contamination in environmental ecosystems has emerged as a significant health hazard. Conventional analytical methods are suboptimal, hindered by their inefficiency in analyzing nanoplastics at low concentrations and their time-intensive processes. In this context, we have developed an innovative approach that employs luminescent metal–phenolic networks (L-MPNs) coupled with surface-enhanced Raman spectroscopy (SERS) to separate and label nanoplastics, enabling rapid, sensitive and quantitative detection. Our strategy utilizes L-MPNs composed of zirconium ions, tannic acid, and rhodamine B to uniformly label nanoplastics across a spectrum of sizes (50–500 nm) and types (e.g., polystyrene, polymethyl methacrylate, polylactic acid). Rhodamine B (RhB) functions as a Raman reporter within these L-MPNs-based SERS tags, providing the requisite sensitivity for trace measurement of nanoplastics. Moreover, the labeling with L-MPNs aids in the efficient separation of nanoplastics from liquid media. Utilizing a portable Raman instrument, our methodology offers cost-effective, swift, and field-deployable detection capabilities, with excellent sensitivity in nanoplastic analysis and a detection threshold as low as 0.1 μg/mL. Overall, this study proposes a highly promising strategy for the robust and sensitive analysis of a broad spectrum of particle analytes, underscored by the effective labeling performance of L-MPNs when coupled with SERS techniques. [Display omitted] • A novel L-MPNs strategy was developed to facilitate labeling and separation of nanoplastics. • Formation of L-MPNs@NPs was validated by microscopic and spectroscopic measurements. • SERS approach allows detection of various sizes (50–500 nm) and types of nanoplastics with a LOD of 0.1 ppm. • Nanoplastics can be successfully detected into real environmental water systems. [ABSTRACT FROM AUTHOR]

Precisely determining which bonds are more sensitive when plastic aging occurs is critical to better understand the mechanisms of toxic release and microplastics formation. However, the relationship between chemical bonds with the active aging sites changes and the aging behavior of plastics at an early age is still unclear. Herein, the mechanical behavior of four polymers with different substituents was characterized by the high-resolution AFM. Young's modulus (YM) changes suggested that the cleavage of C-Cl bonds in PVC, C-H bonds in PE and PP, and C-F bonds in PTFE are the main active aging sites for plastic aging. The aging degree of the plastics followed the order of PVC > PP > PE > PTFE. Two aging periods exhibited different YM change behavior, the free radical and cross-linking resulted in a minor increase in YM during the initiation period. Numerous free radicals formed and cross-linking reaction happened, causing a significant increase in YM during the propagation period. Raman spectroscopy verified the formation of microplastics. This research develops promising strategies to quantitatively evaluate the aging degrees using AFM and establish the relationship between chemical bonds and mechanical behavior, which would provide new method to predict plastic pollution in actual environments. [Display omitted] • C-X bonds are the main aging active sites of plastics with different substituents. • Plastics with different substituents have different changing trends in Young's modulus during aging. • Micromechanical behavior affects the formation of microplastics. • The effect of chemical bonds on micromechanical properties was investigated. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) and fluoxetine are ubiquitous emerging pollutants in aquatic environments that may interact with each other due to the carrier effects of MPs, posing unpredictable risks to non-target organisms. However, limited studies have focused on the carrier effects of MPs in the aquatic food chain. This study evaluated the influences of polystyrene MPs on the trophic transfer and biotoxicity of fluoxetine in a simple food chain composed of brine shrimp (Artemia nauplii) and zebrafish (Danio rerio). The finding reveals that carrier effects of MPs enhanced the accumulation of waterborne fluoxetine in brine shrimp, but suppressed that in zebrafish due to the distinct retention times. The accumulated fluoxetine in shrimp was further transferred to fish through the food chain, which was alleviated by MPs due to their cleaning effects. In addition, the specific neurotransmission biotoxicity in fish induced by fluoxetine was mitigated by MPs, whilst the oxidative damage, apoptosis, and immune responses in zebrafish were reversely enhanced by MPs due to the stimulating effect. These findings highlight the alleviating effects of MPs on the trophic transfer and specific biotoxicity of fluoxetine in the food chain, providing new insights into the carrier effects of MPs in aquatic environments in the context of increasing global MP pollution. [Display omitted] • MPs altered the accumulation of fluoxetine in different trophic organisms. • Fluoxetine exhibited transfer in the food chain but did not undergo biomagnification. • MPs inhibited the trophic transfer of fluoxetine in the food chain. • The specific biotoxicity induced by fluoxetine in fish was alleviated by MPs. [ABSTRACT FROM AUTHOR]

Microplastics and antibiotics are prevalent and emerging pollutants in aquatic ecosystems, but their interactions in aquatic food chains remain largely unexplored. This study investigated the impact of polypropylene microplastics (PP-MPs) on oxytetracycline (OTC) trophic transfer from the shrimp (Neocaridina denticulate) to crucian carp (Carassius auratus) by metagenomic sequencing. The carrier effects of PP-MPs promoted OTC bioaccumulation and trophic transfer, which exacerbated enterocyte vacuolation and hepatocyte eosinophilic necrosis. PP-MPs enhanced the inhibitory effect of OTC on intestinal lysozyme activities and complement C3 levels in shrimp and fish, and hepatic immunoglobulin M levels in fish (p < 0.05). Co-exposure of MPs and OTC markedly increased the abundance of Actinobacteria in shrimp and Firmicutes in fish, which caused disturbances in carbohydrate, amino acid, and energy metabolism. Moreover, OTC exacerbated the enrichment of antibiotic resistance genes (ARGs) in aquatic animals, and PP-MPs significantly increased the diversity and abundance of ARGs and facilitated the trophic transfer of teta and tetm. Our findings disclosed the impacts of PP-MPs on the mechanism of antibiotic toxicity in aquatic food chains and emphasized the importance of gut microbiota for ARGs trophic transfer, which contributed to a deeper understanding of potential risks posed by complex pollutants on aquatic ecosystems. [Display omitted] • The carrier effects of PP-MPs promoted OTC bioaccumulation and trophic transfer. • OTC and MPs produced synergistic effects on immunotoxic responses of shrimp and fish. • OTC in combination with MPs disrupted gut microbial communities of aquatic animals. • PP-MPs and OTC facilitated enrichment effects and trophic transfer of ARGs. [ABSTRACT FROM AUTHOR]

Microplastics are known to negatively affect anaerobic digestion (AD) of waste activated sludge. However, whether thermal hydrolysis (TH) pretreatment alters the impact of microplastics on sludge AD remains unknown. Herein, the effect of TH on the impact of polyethylene (PE) microplastics in sludge AD was investigated. The results showed that the inhibition of methane production by PE at 100 particles/g total solids (TS) was reduced by 31.4% from 12.1% to 8.3% after TH at 170 °C for 30 min. Mechanism analysis indicated TH reduced the potential for reactive oxygen species production induced by PE, resulting in a 29.1 ± 5.5% reduction in cell viability loss. In addition, additive leaching increased as a result of rapid aging of PE microplastics by TH. Acetyl tri-n-butyl citrate (ATBC) release from PE with 10 and 100 particles/g TS increased 11.5-fold and 8.6-fold after TH to 68.2 ± 5.5 μg/L and 124.0 ± 5.1 μg/L, respectively. ATBC at 124.0 μg/L increased methane production by 21.4%. The released ATBC enriched SBR1031 and Euryarchaeota, which facilitate the degradation of proteins and promote methane production. This study reveals the overestimated impact of PE microplastics in sludge AD and provides new insights into the PE microplastics-induced impact in practical sludge treatment and anaerobic biological processes. [Display omitted] • TH mitigated the inhibition of PE microplastics on sludge anaerobic digestion. • PE microplastic-induced reactive oxygen species production was reduced by TH. • ATBC release from PE microplastics increased 8.6-fold after TH. • ATBC at 124.0 μg/L increased methane production by 21.4%. • The impact of PE microplastics in sludge anaerobic digestion was overestimated. [ABSTRACT FROM AUTHOR]

The plastic production that contributes to the global plastic reservoir presents a major challenge for society in managing plastic waste and mitigating the environmental damage of microplastic (MP) pollution. In the environment, the formation of biomolecular corona around MPs enhance the stability of MP suspensions, influencing the bioavailability and toxicity of MPs. Essential physical properties including MP stability, dispersibility, agglomeration, and dimensional size must be precisely defined and measured in complex media taking into account the formation of a protein corona. Using static multiple light scattering (SMLS), small angle X-ray scattering (SAXS), Raman microscopy, and scanning electron microscopy (SEM), we measured the particle size, density, stability, and agglomeration state of polyethylene and polypropylene MPs stabilized in aqueous suspension by BSA. SEM analysis revealed the formation of nanoplastic debris as MP suspensions aged. Our results suggest that protein adsorption favors the formation of secondary nanoplastics, potentially posing an additional threat to ecosystems. This approach provides analytical methodologies by integrating SEM, SMLS, and SAXS, for characterizing MP suspensions and highlights the effect of the protein corona on size measurements of micro/nanoplastics. Our analysis demonstrates the detectability of secondary nanoplastics by SEM, paving the way for monitoring and controlling human exposure. [Display omitted] • Nanoplastics debris formed during shelf-storage of PE without mechanical stress. • The protein corona favors the release of secondary nanoplastics. • MP size analyses by SMLS on the colloidal suspension and SEM on deposits are consistent. • MP density was determined in suspension by combining SAXS and SEM. • Stabilization of hydrophobic MPs by a biocorona is essential for dimensional analysis. [ABSTRACT FROM AUTHOR]

Microplastics and nanoplastics are ubiquitous in rivers and undergo environmental aging. However, the molecular mechanisms of plastic aging and the in-depth effects of aging on ecological functions remain unclear in waters. The synergies of microplastics and nanoplastics (polystyrene as an example) with natural organic small molecules (e.g., natural hyaluronic acid and vitamin C related to biological tissue decomposition) are the key to producing radicals (•OH and •C). The radicals promote the formation of bubbles on plastic surfaces and generate derivatives of plastics such as monomer and dimer styrene. Nanoplastics are easier to age than microplastics. Pristine plastics inhibit the microbial Shannon diversity index and evenness, but the opposite results are observed for aging plastics. Pristine plastics curb pectin decomposition (an indicator of plant-originated refractory carbon), but aging plastics promote pectin decomposition. Microplastics and nanoplastics undergoing aging processes enhance the carbon biogeochemical cycle. For example, the increased carbohydrate active enzyme diversity, especially the related glycoside hydrolase and functional species Pseudomonas and Clostridium , contributes to refractory carbon decomposition. Different from the well-studied toxicity and aging of plastic pollutants, this study connects plastic pollutants with biological tissue decomposition, biodiversity and climate change together in rivers. [Display omitted] • Natural organic small molecules promote plastic aging. • Nanoplastics are easier to age than microplastics. • Aging plastics promote refractory carbon decomposition. • Aging plastics promote the carbon cycle in waters. • Carbohydrate active enzyme (CAZyme) diversity is boosted. [ABSTRACT FROM AUTHOR]

Continuous exposure to plastic pollutants may have serious consequences on human health. However, most toxicity assessments focus on non-environmentally relevant particles and rarely investigate long-term effects such as cancer induction. The present study assessed the carcinogenic potential of two secondary nanoplastics: polyethylene terephthalate (PET) particles generated from plastic bottles, and a biodegradable polylactic acid material, as respective examples of environmentally existing particles and new bioplastics. Pristine polystyrene nanoplastics were also included for comparison. A broad concentration range (6.25–200 μg/mL) of each nanoplastic was tested in both the initiation and promotion conditions of the regulatory assessment-accepted in vitro Bhas 42 cell transformation assay. Parallel cultures allowed confirmation of the efficient cellular internalisation of the three nanoplastics. Cell growth was enhanced by polystyrene in the initiation assay, and by PET in both conditions. Moreover, the number of transformed foci was significantly increased only by the highest PET concentration in the promotion assay, which also showed dose-dependency, indicating that nano PET can act as a non-genotoxic tumour promotor. Together, these findings support the carcinogenic risk assessment of nanoplastics and raise concerns regarding whether real-life co-exposure of PET nanoplastics and other environmental pollutants may result in synergistic transformation capacities. [Display omitted] • Polyethylene terephthalate, polylactic acid, and polystyrene nanoplastics were used. • Carcinogenicity was assessed using the in vitro Bhas 42 cell transformation assay. • Only polyethylene terephthalate (PET) nanoplastics induced cell transformation. • PET nanoplastics acted through a tumour promotion mode of action. • The three types of nanoplastics were efficiently internalised into cells. [ABSTRACT FROM AUTHOR]

Pyrolysis-gas chromatography coupled to Orbitrap-mass spectrometry is a novel technique that allows the low level and precise determination of microplastics in environmental samples. In this paper, we develop and assess the target and untargeted performance of Pyr-GC-Orbitrap-MS. The method was optimized for 10 plastic polymers: polymethyl methacrylate, nylon-6,6, polypropylene, nitrile butadiene rubber, polyvinyl chloride, polyethylene terephthalate, acrylonitrile butadiene styrene, polyethylene, polycarbonate, and polystyrene. Standards were home-made using a diamond driller to attain mean sizes within the range of 45–382 µm. A step-by-step optimization of the analytical procedure was carried out. First, accurate mass measurement of each polymer at 60,000 resolution was studied to select the 3 most intense and selective quantification and confirmation ions. Second, internal standard quantification was optimized, and good linearity, repeatability, and reproducibility were obtained. Blank contribution and instrumental detection limit were evaluated for each polymer. Finally, the combined and expanded uncertainty of the Pyr-GC-Orbitrap-MS method was calculated to determine the sources of variation, considering that home-made standards were used. To evaluate method performance, targeted and non-targeted analysis of indoor air samples collected from gyms and department stores were carried out. The Pyr-GC-Orbitrap-MS methodology herein described can be applied for the quantitative assessment of MPs and other substances in different matrices. [Display omitted] • Pyrolysis with orbitrap mass spectrometry allows detection of microplastics in air. • Microplastic standards allow calibration and calculation of quality parameters. • Exact mass measurements allows target and non-target analysis of microplastics. • The uncertainty of the method allows validating the method for trace concentrations. • Microplastics and other contaminants have been detected in air from stores and gyms. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) act as carriers for organic pollutants (e.g. antibiotics) and microorganisms (e.g. bacteria) in waters, leading to the proliferation of antibiotic resistance genes. Moreover, the antibiotics adsorbed on MPs may exacerbate this process. For further research, it is necessary to understand the types and amounts of antibiotics adsorbed on MPs. However, due to the heavy work of MPs collection and sample pretreatment, there is a lack of analytical methods and relevant data. In this study, an in-tube solid phase microextraction (IT-SPME) on-line coupled to HPLC-MS/MS method based on amorphous precursor polymer of three-dimensional covalent organic frameworks/monolith-based composite adsorbent was developed, which could efficiently capture, enrich and analyze tetracycline (TCs) antibiotics. Under the optimal extraction parameters, the developed method was capable of detecting TCs at levels as low as 0.48–1.76 pg. This method was applied to analyze the TCs adsorbed on MPs of different particle sizes in mariculture water for the first time, requiring a minimum amount of MPs of only 1 mg. Furthermore, it was observed that there could be an antagonistic relationship between algal biofilm and TCs loaded on MPs. This approach could open up new possibilities for analyzing pollutants on MPs and support deeper research on MPs. [Display omitted] • Amorphous precursor polymer of COFs was developed as adsorbent in IT-SPME for TCs. • The established approach was capable of detecting TCs as low as 0.48-1.76 pg. • TCs adsorbed on MPs could be measured with a minimal requirement of MPs of 1 mg. • TCs adsorbed on MPs of different sizes in mariculture water were analyzed for the first time. • There may be antagonistic relationship between algal biofilm and TCs attached to MPs. [ABSTRACT FROM AUTHOR]

The escalating accumulation of plastic waste in ecosystems poses a significant health concern to soil environment, yet the environmental effects of plastics remains largely unexplored. Biodegradable plastics could offer a viable alternative to conventional persistent plastics, but our understanding of their potential benefits or detrimental effects on the decomposition of plant debris by soil biomass is limited. In this study, we conducted a year-long field experiment to examine the environmental response and impact on plant debris decomposition in the presence of varying quantities of persistent versus biodegradable plastics. Our findings indicate that the decomposition rate decreased by 2.8–4.9% for persistent plastics, while it increased by 1.3–4.2% for biodegradable plastics. Persistent plastics primarily induced adverse effects, including a reduction in soil nutrients, microbial diversity, bioturbation, enzyme activity, easily decomposable carbon, and microbial biomass carbon in plant debris. In contrast, biodegradable plastics resulted in beneficial effects such as an increase in enzyme activity, microbial biomass carbon, and easily decomposable carbon. We also observed that the decomposition rate of plant residues and nutrient release are closely associated with changes in the organic carbon chemical structure induced by different plastic film fragments. A significant shift in alkoxy carbon content facilitated the release of nutrients and soluble carbon, while modifications in carboxyl and aromatic carbon content hindered their release. Overall, our study reveals over one year that biodegradable plastics primarily induce positive effects on the decomposition of soil organic matter. [Display omitted] • PPF and BPF remnants exert contrasting impacts on the soil environment. • BPF promote the decomposition of plant debris. • Nutrient release is intimately tied to alterations in its organic carbon structure. [ABSTRACT FROM AUTHOR]

Biodegradable polymers have been proposed as an alternative to conventional plastics to mitigate the impact of marine litter, but the research investigating their toxicity is still in its infancy. This study evaluates the potential ecotoxicological effects of both virgin and marine-incubated microparticles (MPs), at environmentally relevant concentration (0.1 mg/l), made of different biodegradable polymers (Polycaprolactone, Mater-Bi, cellulose) and conventional polymers (Polyethylene) on Mytilus galloprovincialis by using transcriptomics. This approach is increasingly being used to assess the effects of pollutants on organisms, obtaining data on numerous biological pathways simultaneously. Whole hepatopancreas de novo transcriptome sequencing was performed, individuating 972 genes differentially expressed across experimental groups compared to the control. Through the comparative transcriptomic profiling emerges that the preponderant effect is attributable to the marine incubation of MPs, especially for incubated polycaprolactone (731 DEGs). Mater-Bi and cellulose alter the smallest number of genes and biological processes in the mussel hepatopancreas. All microparticles, regardless of their polymeric composition, dysregulated innate immunity, and fatty acid metabolism biological processes. These findings highlight the necessity of considering the interactions of MPs with the environmental factors in the marine ecosystem when performing ecotoxicological evaluations. The results obtained contribute to fill current knowledge gaps regarding the potential environmental impacts of biodegradable polymers. [Display omitted] • M. galloprovincialis hepatopancreas de novo transcriptome sequencing was performed. • All microparticle (MPs) treatments significantly alter the mussel transcriptome profile. • The marine incubation of MPs increases the transcriptional effects of all polymers. • Biopolymers (cellulose and Mater-Bi) exposure causes lower transcriptional alteration. • Innate immunity and lipid metabolisms processes are the most affected by MPs exposure. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) and pesticides commonly exist in the environment, yet the interactions between them and their subsequent impacts on plants remain poorly understood. Thus, this study aimed to investigate the impacts of differently charged polystyrene (PS) MPs, including PS-COO-, PS and PS-NH 3 + MPs, on the fate of 14C-labelled new antiviral pesticide Dufulin (DFL) in a hydroponic tomato system. The results showed that MPs greatly reduced the growth of tomato plants, with suppression of 18.4–30.2%. Compared to the control group, PS-COO-, PS and PS-NH 3 + MPs also reduced the bioaccumulation of DFL in whole tomato plants by 40.3%, 34.5%, and 26.1%, respectively. Furthermore, MPs influenced the translocation of DFL in plant tissues, and the values decreased at the rates of 38.7%, 26.5% and 15.7% for PS-COO-, PS and PS-NH 3 +, respectively. Interestingly, compared to the control group, PS-COO- exhibited a profound inhibitory effect on DFL concentrations in tomatoes, potentially resulting in a lower dietary risk in the hydroponic tomato system. This may be due to the strong adsorption between PS-COO- and DFL, and PS-COO- may also inhibit the growth of tomato plants. Overall, our study could provide valuable insights into the risk assessment of DFL in the presence of MPs in plant systems. [Display omitted] • Effects of differently charged PS-MPs on DFL fate in hydroponics were different. • Compared with DFL, PS-MPs in combination with DFL reduced tomatoes' biomass and yield. • BCFs of DFL in tomato decreased in the order of: control > PS-NH3 + > PS > PS-COO-. • PS-MPs greatly inhibited translocation of DFL from roots to aerial parts of tomato. • PS-COO- significantly inhibited dietary risk of DFL in the hydroponic tomato system. [ABSTRACT FROM AUTHOR]

Microplastics and antibiotics not only pollute aquatic environments and threaten human health, but are also tricky to remove. Microplastics adsorb antibiotics, and, before being released into the natural environment, most microplastics pass through some wastewater treatment and/or disinfection (such as chlorination) facilities. It is therefore necessary to understand how these treatment processes may affect or alter microplastics' properties, particularly their ability to adsorb antibiotics, and whether or not the two, when bound together, may present exacerbated harm to the environment. This study used both laboratory tests and molecular dynamics simulation to investigate the mechanism through which chlorinated microplastics (specifically polystyrene) adsorb the antibiotic tetracycline, and showed that chlorination gave the polystyrene a larger interaction area (> 21%) and more free energy (> 14%) to adsorb tetracycline. Van der Waals (vdW) forces played a more dominant role than electrostatics in facilitating tetracycline's adsorption. Moreover, a density functional theory analysis demonstrated that the vdW potentials of the microplastics decreased as more and more hydrogen atoms became replaced by chlorine, suggesting a facilitation of the adsorption of polycyclic antibiotic molecules. The experimental results confirmed the simulation's prediction that a higher degree of chlorination significantly increases the polystyrene's adsorption capacity, whereas pH and salinity had almost no effect on the adsorption. This study demonstrates that disinfection elevates the risk of antibiotics adhering to and accumulating on the surface of microplastics. [Display omitted] • Chlorination improved microplastics' tetracycline adsorption by more than 3 times. • VdW forces dominated microplastics' adsorption of tetracycline (over electrostatic). • Chlorination increased the vdW potentials of microplastics by chlorine substitution. • The amount of tetracycline adsorbed by microplastics increased with chlorine dosage. [ABSTRACT FROM AUTHOR]

Understanding of the environmental behaviors of microplastics is limited by a lack of knowledge about how photoaging influences biofilm formation on microplastics in soil. Here, original microplastics (OMPs) and photoaged-microplastics (AMPs) were incubated in soil to study the effect of photoaging on formation and characteristics of biofilm on the poly (butylene succinate) microplastics. Because photoaging decreased the hydrophobicity of the microplastic, the biomass of biofilm on the OMPs was nearly twice that on the AMPs in the early stage of incubation. However, the significance of the substrate on biomass in the biofilm declined as the plastisphere developed. The bacterial communities in the plastisphere were distinct from, and less diverse than, those in surrounding soil. The dominant genera in the OMPs and AMPs plastispheres were Achromobacter and Burkholderia , respectively, indicating that photoaging changed the composition of the bacterial community of biofilm at the genus level. Meantime, photoaging decreased the complexity and stability of the plastisphere bacterial community network. Results of Biolog ECO-microplate assays and functional prediction from amplicons showed that photoaging treatment enhanced the carbon metabolic capacity of the microplastic biofilm. This study provides new insights into the formation of plastispheres in soil. [Display omitted] • Aging decreased the interaction of soil microplastics with surrounding microbes. • The influence of substrates on microbial biomass declined with the development of plastisphere. • Microplastics with stronger hydrophobicity have higher affinities to microorganisms. • Aging decreased the complex and stability of network in plastisphere bacterial communities. • Aging enhanced the carbon metabolic capacity of bacterial communities in plastisphere. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) from the incomplete degradation of agricultural mulch can stress the effectiveness of biofertilizers and ultimately affect the rhizosphere environment of crops. Yet, the involved mechanisms are poorly known and robust empirical data is generally lacking. Here, conventional polyethylene (PE) MPs and poly(butylene adipate-co-butylene terephthalate) (PBAT) / poly(lactic acid) (PLA) biodegradable MPs (PBAT-PLA BioMPs) were investigated to assess their potential impact on the rhizosphere environment of Brassica parachinensis in the presence of Bacillus amyloliquefaciens biofertilizer. The results revealed that both MPs caused different levels of inhibited crop both above- and belowground crop biomass (up to 50.11% and 57.09%, respectively), as well as a significant decrease in plant height (up to 48.63% and 25.95%, respectively), along with an imbalance of microbial communities. Transcriptomic analyses showed that PE MPs mainly affected root's vitamin metabolism, whereas PBAT-PLA BioMPs mainly interfered with the lipid's enrichment. Metabolomic analyses further indicated that PE MPs interfered with amino acid synthesis that involved in crops' oxidative stress, and that PBAT-PLA BioMPs mainly affected the pathways associated with root growth. Additionally, PBAT-PLA BioMPs had a bigger ecological negative impact than did PE MPs, as evidenced by more pronounced alterations in root antioxidant abilities, a higher count of identified differential metabolites, more robust interrelationships among rhizosphere parameters, and a more intricate pattern of impacts on rhizosphere metrics. This study highlights the MPs' impact on crop rhizosphere in a biofertilizer environment from a rhizosphere multi-omics perspective, and has theoretical implications for scientific application of biofertilizers. [Display omitted] • Both PE and PBAT-PLA BioMPs inhibited Brassica parachinensis growth. • MPs mainly affected rhizospheric bacterial communities and biodiversity. • MPs disrupted genes expression and related metabolic function in B. parachinensis. • PBAT-PLA BioMPs had bigger rhizosphere ecological responses than PE MPs. • The mulches' using with biofertilizer requires attention to rhizosphere profiles. [ABSTRACT FROM AUTHOR]

The debris of plastics with a size < 5 mm, called microplastics, possess long-lived legacies of plastic pollution and a growing threat to human beings. The adverse effects and corresponding molecular mechanisms of microplastics are still largely unknown and must be prioritized. Antibiotics commonly co-existed with microplastics; the current study investigated the syngenetic toxic effect of doxycycline (Dox) and polystyrene microplastics (PS). Specifically, we found that Dox combined with PS exposure perturbed gut microbiota homeostasis in mice, which mediated brain lesions and inflammation with a concomitant decline in learning and memory behaviors through the gut-brain axis. Of note, PS exposure resulted in intestinal damage and structural change, but Dox did not accelerate the disruption of intestinal barrier integrity in PS-treated mice. Interestingly, fecal microbiota transplantation (FMT) can reverse neurological impairment caused by combined PS and Dox exposure via compensating gut microbes; therefore, the learning and memory abilities of mice were also recovered. This work not only provides insights into the syngenetic effect of microplastics and antibiotics and highlights their distal neurotoxicity through the gut-brain axis but also offers a promising strategy against their combined toxicity. [Display omitted] • Dox combined with PS exposure perturbed gut microbiota homeostasis in mice. • Co-exposure causes brain lesions and inflammation accompanied by decreased learning and memory behaviors through the gut-brain axis. • Fecal microbiota transplantation can reverse neurological impairment via compensating gut microbes. [ABSTRACT FROM AUTHOR]

In their Letter to the Editor, Nizzetto et al. challange a recent article in which I show that there has been unwarranted alarmism about biodegradable mulch films due to the publication of numerous articles based on preliminary data that are irrelevant for drawing conclusions on environmental risk. The tendency to over-emphasise results in order to attract attention is a growing problem in the scientific world and has been studied by many scholars. Nizzetto et al. accuse me of not using scientific methodology and of not disclosing that I am a scientist working for a company that produces biodegradable plastics. In this rebuttal I show that Nizzetto et al.'s accusations suffer from a number of logical fallacies, in particular the "straw man" fallacy and the "ad hominem" fallacy. [ABSTRACT FROM AUTHOR]

Biodegradable plastic bags (BPBs), meant for eco-friendly, often inadequately degrade in compost, leading to microplastic pollution. In this study, the effect of Fenton-like reaction with Fe 3 O 4 nanoparticles (NMs) on the plastisphere microorganisms' evolution and the BPBs' aging mechanism was revealed by co-composting of food waste with BPBs for 40 days. The establishment of the Fenton-like reaction was confirmed, with the addition of Fenton-like reagent treatments resulting in an increase of 57.67% and 37.75% in H 2 O 2 levels during the composting, compared to the control group. Moreover, the structural characterization reveals that increasing oxygen content continuously generates reactive free radicals on the surface, leading to the formation of oxidative cavities. This process results in random chain-breaking, significantly reducing molecular weights by 39.27% and 38.81%, thus showcasing a deep-seated transformation in the plastic's molecular structure. Furthermore, the microbial network suggested that the Fenton-like reaction enriched plastisphere keystone species, thus accelerating the BPBs' aging. Additionally, the Fenton-like reaction improved compost maturity and reduced greenhouse gas emissions. These results reveal the bio-chemical mechanisms of BPBs aging and random chain-breaking by the Fenton-like reaction, under alternating oxidative/anoxic conditions of composting and provide a new insight to resolve the BPBs' pollutions. [Display omitted] • Fenton-like system boosts BPBs degradation in compost, increasing H 2 O 2 by 57.67%. • Fenton-like reaction enriches keystone species for BPBs aging. • Biochemical action reduces BPBs molecular weight by 39.27%. • Raises humic substance synthesis to 33.64 g•kg−1 in compost. • The biochemical mechanism of Fenton-like reaction to BPBs is random chain-breaking. [ABSTRACT FROM AUTHOR]

Biodegradable mulches are widely recognized as ecologically friendly substances. However, their degradation percentage upon entering soils may vary based on mulch type and soil microbial activities, raising concerns about potential increases in microplastics (MPs). The effects of using different types of mulch on soil carbon pools and its potential to accelerate their depletion have not yet well understood. Therefore, we conducted an 18-month experiment to investigate mulch biodegradation and its effects on CO 2 emissions. The experiment included burying soil with biodegradable mulch made of polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT), and control treatments with traditional mulch (PE) and no mulch (CK). The results indicated that PE did not degrade, and the degradation percentage of PLA and PBAT were 46.2% and 88.1%, and the MPs produced by the degradation were 6.7 × 104 and 37.2 × 104 items/m2, respectively. Biodegradable mulch, particularly PLA, can enhance soil microbial diversity and foster more intricate bacterial communities compared to PE. The CO 2 emissions were 0.58, 0.74, 0.99, and 0.86 g C/kg in CK, PE, PLA, , PBAT, respectively. A positive correlation was observed between microbial abundance and diversity with CO 2 emissions, while a negative correlation was observed with soil total organic carbon. Biodegradable mulch enhanced the transformation of soil organic C into CO 2 by stimulating microbial activity. [Display omitted] • Biodegradable mulch produced 7-37 × 104 items/m2 of microplastics after 18-month degradation. • Biodegradable mulch increased 25% CO 2 emission than Polyethylene. • Biodegradable mulch promoted soil C converted to CO 2 by stimulating microbial activity. • Biodegradation of soil mulch has the risk of increasing CO 2 and reducing soil C storage. • Polybutylene adipate terephthalate produce more microplastics, while polylactic acid more CO 2. [ABSTRACT FROM AUTHOR]

Ubiquitous pollution due to microplastics through the food chain is a major cause of various deleterious effects on the human health. The aim of this study was to determine the existence of microplastics and the internal mechanism of microplastics as accelerators of cholelithiasis. Gallstones were collected from 16 patients after cholecystectomy, and microplastics in the gallstones were detected through laser direct infrared and pyrolysis gas chromatography mass spectrometry examinations. Mice model of gallstone were constructed with or without different diameters of microplastic (0.5, 5 and 50 µm). The affinity between microplastic and cholesterol or bilirubin was tested by co-culturing and qualified using molecular dynamics simulations. Finally, altered gut microbiota among the groups were identified using 16 s rRNA sequencing. The presence of microplastics in the gallstones of all the patients were confirmed. Microplastic content was significantly higher in younger chololithiasis patients (age<50 years). Mice fed a high-cholesterol diet with microplastic drinks showed more severe chololithiasis. In terms of the mechanism, microplastics showed a higher affinity for cholesterol than for bilirubin. Significant alterations in the gut microbiota have also been identified after microplastic intake in mice. Our study revealed the presence of microplastics in human gallstones, showcasing their potential to aggravate chololithiasis by forming large cholesterol-microplastic heteroaggregates and altering the gut microbiota. [Display omitted] • Microplastic were present in gallstones, with significantly higher levels observed in younger cholelithiasis patients. • Microplastic ingestion accelerated the formation of gallstone in mice. • Microplastics exhibited strong affinity for cholesterol and formed cholesterol-microplastic heteroaggregates. • Microplastic ingestion altered the composition of the gut microbiota in mice fed a high-cholesterol diet. [ABSTRACT FROM AUTHOR]

Discarding PET plastic (dPET) causes serious environmental pollution and enormous fossil resources waste. Processing techniques have mainly focused on the conversion of dPET into monomers, with minimal reports highlighting their transformation into high–value materials. This work intends to transform dPET into a high–performance material with potential alternative value in harsh production environments. The soft and hard segments of the thermoplastic polyester elastomeric (TPEE) molecular structure are reacted and cross–linked with dPET using a facile one–pot process, and two main polymers, (C 8 H 4 O 4) n and ((C 16 H 18 O 4) 0.76 ·(C 4 H 8 O) 0.24) n are generated after the reaction. Through chemical reactions between TPEE and dPET, new characteristic products and chemical bond–crossing structures are formed, while the resulting product particles or multiple TPEE particles are anchored by the high viscosity of dPET, which endows the material with superior tensile strength (34.21 MPa) and impact resistance. The glass transition temperature (T g) of the material implies that neither the molecular chain nor the chain segments can move, while only the atoms or groups composing the molecule vibrate at their equilibrium positions. The development of this new treatment method may contribute to the reduction of environmental pollution and the improvement of the high–value conversion and utilization of dPET. [Display omitted] • An innovative strategy to convert dPET into functional materials was developed. • The fabricated material showed excellent tensile strength and impact resistance. • (C 8 H 4 O 4) n and (C 16 H 18 O 4) 0.76 ·(C 4 H 8 O) 0.24) n were generated after polymerization. • Newly formed long–chain polymer is responsible for superior tensile strength. • This study gives a new alternative approach to high-value utilization of dPET. [ABSTRACT FROM AUTHOR]

The extensive use of plastics has given rise to microplastics, a novel environmental contaminant that has sparked considerable ecological and environmental concerns. Biodegradation offers a more environmentally friendly approach to eliminating microplastics, but their degradation by marine microbial communities has received little attention. In this study, we used iron-enhanced marine sediment to augment the natural bacterial community and facilitate the decomposition of polyethylene (PE) microplastics. The introduction of iron-enhanced sediment engendered an augmented bacterial biofilm formation on the surface of polyethylene (PE), thereby leading to a more pronounced degradation effect. This novel observation has been ascribed to the oxidative stress-induced generation of a variety of oxygenated functional groups, including hydroxyl (-OH), carbonyl (-C O), and ether (-C-O) moieties, within the microplastic substrate. The analysis of succession in the community structure of sediment bacteria during the degradation phase disclosed that Acinetobacter and Pseudomonas emerged as the principal bacterial players in PE degradation. These taxa were directly implicated in oxidative metabolic pathways facilitated by diverse oxidase enzymes under iron-facilitated conditions. The present study highlights bacterial community succession as a new pivotal factor influencing the complex biodegradation dynamics of polyethylene (PE) microplastics. This investigation also reveals, for the first time, a unique degradation pathway for PE microplastics orchestrated by the multifaceted marine sediment microbiota. These novel insights shed light on the unique functional capabilities and internal biochemical mechanisms employed by the marine sediment microbiota in effectively degrading polyethylene microplastics. [Display omitted] • Natural bacterial microbiota exhibits a crucial role in degradation of microplastics. • Enhancement of iron can significantly improve the biodegradation of microplastics. • Bacterial community succession is a key determinant in degradation of microplastics. • Two degradation pathways of microplastics by marine microbiota have been proposed. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) accumulation in sediments has posed a huge threat to freshwater ecosystems. However, it is still unclear the effect of MPs on riparian sediment structures and contaminant adsorption under different hydrological processes. In this study, three concentrations of polyamide (PA) MPs-treated sediments (0.1%, 1%, and 10%, w/w) were subjected to natural (NA) exposure, dry-wet (DW) cycles, and freeze-thaw (FT) cycles. The results indicated that PA MPs-added sediment increased the micro-aggregates by 10.1%−18.6% after FT cycles, leading to a decrease in aggregate stability. The pH, OM, and DOC of sediments were significantly increased in DW and FT treatments. In addition, the increasing concentration of PA MPs showed an obvious decrease in aromaticity, humification, and molecular weight of sediment DOM in FT treatments. Also, high level of MPs was more likely to inhibit the formation of humic-like substances and tryptophan-like proteins. For DW and FT cycles, 0.1% and 1% PA MPs-treated sediments slightly increased the adsorption capacity of Cd(II), which may be ascribed to the aging of MPs. Further correlation analysis found that DW and FT altered the link between DOM indicators, and aggregate stability was directly related to the changes in sediment organic carbon. Our findings revealed the ecological risk of MPs accumulating in riparian sediments under typical hydrological processes. [Display omitted] • Macro-aggregate and aggregate stability significantly reduced by combined FT cycles and MPs. • DW and FT cycles showed an obvious increase in sediment properties. • The aromaticity and humification degree of DOM were significantly decreased in 10% MPs-treated sediment. • DW and FT cycles slightly increased the Cd(II) adsorption onto 0.1% and 1% MPs-treated sediments. • There was a relationship between aggregate stability and sediment organic carbon. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have emerged as a significant global environmental concern, particularly within agricultural soil systems. The extensive use of plastic film mulching in cotton cultivation has led to the alarming presence of MP pollution in cotton fields. However, the uptake and effects of MPs on the growth of cotton plants are poorly understood. In this study, we conducted a comprehensive analysis of hydroponically cultured cotton seedlings at the phenotypic, transcriptional, and metabolic levels after exposure to carboxyl-modified polystyrene microplastics (PS-COOH). Treatment with three concentrations of PS-COOH (100, 300, and 500 mg/L) resulted in notable growth inhibition of treated plants and exhibited a dose-dependent effect. And, PS-COOH can invade cotton roots and be absorbed through the intercellular spaces via apoplastic uptake, with accumulation commensurate with treatment duration. Transcriptomic analysis showed significant up-regulation of genes associated with antioxidant activity in response to 300 mg/L PS-COOH treatment, suggesting the induction of oxidative stress. In addition, the PS-COOH treatment activated the phenylpropanoid biosynthesis pathway, leading to lignin and flavonoid accumulation, and altered sucrose catabolism. These findings illustrate the absorption and effects of MPs on cotton seedlings and offer valuable insights into the potential toxicity of MPs to plants in soil mulched with plastic film. [Display omitted] • Cotton exhibited a dose-dependent phenotypic response to PS-COOH. • Fluorescent PS-COOH was absorbed via apoplastic uptake in cotton roots. • Oxidative stress was induced in cotton after PS-COOH treatments. • PS-COOH treatment activated phenylpropanoid pathway and altered sucrose catabolism. [ABSTRACT FROM AUTHOR]

Biosourced and biodegradable plastics offer a promising solution to reduce environmental impacts of plastics for specific applications. Here, we report a novel bacterium named Alteromonas plasticoclasticus MED1 isolated from the marine plastisphere that forms biofilms on foils of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Experiments of degradation halo, plastic matrix weight loss, bacterial oxygen consumption and heterotrophic biosynthetic activity showed that the bacterial isolate MED1 is able to degrade PHBV and to use it as carbon and energy source. The likely entire metabolic pathway specifically expressed by this bacterium grown on PHBV matrices was shown by further genomic and transcriptomic analysis. In addition to a gene coding for a probable secreted depolymerase, a gene cluster was located that encodes characteristic enzymes involved in the complete depolymerization of PHBV, the transport of oligomers, and in the conversion of the monomers into intermediates of central carbon metabolism. The transcriptomic experiments showed the activation of the glyoxylate shunt during PHBV degradation, setting the isocitrate dehydrogenase activity as regulated branching point of the carbon flow entering the tricarboxylic acid cycle. Our study also shows the potential of exploring the natural plastisphere to discover new bacteria with promising metabolic capabilities. [Display omitted] ● A. plasticoclasticus MED1, a novel bacteria isolated from the plastisphere. ● MED1 is a PHBV-degrader forming biofilms. ● Complete metabolic pathway of MED1 for PHBV degradation. ● Activation of the glyoxylate shunt during PHBV degradation. [ABSTRACT FROM AUTHOR]

More single-use plastics are accumulating in the environment, and likewise biodegradable plastics (BPs), which are being vigorously promoted, cannot escape the fate. Currently, studies on the actual degradation of BPs in open-air and freshwaters are underrepresented despite they are potentially headmost leakage and contamination sites for disposable BPs. Herein, we compared the degradation behavior of six BP materials and non-degradable polypropylene (PP) plastics over a 1-year in situ suspension in the high-humidity air, a eutrophic river, and an oligotrophic lake. Moreover, a 3-months laboratory incubation was performed to detect the release of dissolved organic carbon (DOC) from BPs. In both air and freshwaters, poly(p-dioxanone) (PPDO) degraded significantly while PP and polylactic acid (PLA) showed no signs of degradation. The average degradation rates of three poly(butylene adipate- co -terephthalate) (PBAT)-based films varied: 100% in river, 55% in lake, and 10% in air. In addition to PLA, surface chemical groups, hydrophilicity, and thermal stability of BPs changed, and microplastics were found on their surfaces. Correspondingly, BPs with faster degradation rates released relatively higher amounts of DOC. Environmental microbial and chemical characteristics may contribute to differences in BP degradation besides polymer specificity. Altogether, our results indicate the need for appropriate monitoring of BPs. [Display omitted] • The degradation of diverse BPs in air and freshwaters was significantly different. • Single-use PBAT-based films were completely degraded in a eutrophic river over one year. • BPs with faster degradation released higher amounts of dissolved organic carbon. • Polymer type and water quality affected the degradation of BPs. [ABSTRACT FROM AUTHOR]

Microplastic particles are persistent micropollutants that provide a substrate for the growth of bacterial biofilms, posing a threat to the environment. This study explores the changes in commercially available food containers made of conventional (polypropylene PP, polyethylene terephthalate PET), innovative biodegradable (Mater-Bi) and natural (wood and cellulose) materials, when introduced in the surface waters of Lake Maggiore for 43 days. Spectral changes revealed by FT-IR spectroscopy in PET and Mater-Bi, and changes in thermal properties of all human-made material tested indicated a degradation process occurred during environmental exposure. Despite similar bacterial richness, biofilms on PET, PP, and Mater-Bi differed from natural material biofilms and the planktonic community. Human-made material communities showed a higher proportion of potential pathogens, with PET and PP also exhibiting increased abundances of antibiotic resistance genes. Overall, these findings stress the need for dedicated strategies to curb the spread of human-made polymers in freshwaters, including innovative materials that, due to their biodegradable properties, might be perceived less hazardous for the environment. [Display omitted] • Exposure to lake water modified physical and chemical properties of microplastics. • Biofilm composition was peculiar for each incubated material. • Cellulose and wood-based materials showed different biofilm formation and community composition. • Human-made polymers were colonised by similar bacterial communities. • Plastisphere accumulated potential pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Nanoplastics are emerging environmental contaminants, but their presence in environmental and potable water remains largely understudied due to the absence of quantitative analytical methods. In this study, we developed and validated a pretreatment method that combines hydrogen peroxide digestion and Amicon® Stirred Cell ultrafiltration (at 100 kDa, approximately 10 nm) with subsequent detection by pyrolysis gas chromatography–mass spectrometry (Pyr-GC/MS). This method allows for the simultaneous identification and quantification of nine selected nanoplastic types, including poly(ethylene terephthalate) (PET), polyethylene (PE), polycarbonate (PC), polypropylene (PP), poly(methyl methacrylate) (PMMA), polystyrene (PS), polyvinylchloride (PVC), nylon 6, and nylon 66, in environmental and potable water samples based on polymer-specific mass concentration. Limits of quantification ranged from 0.01 to 0.44 µg/L, demonstrating the method's ability to quantitatively detect nanoplastics in environmental and potable water samples. Most of the selected nanoplastics were detected at concentrations of between 0.04 and 1.17 µg/L, except for PC, which was consistently below the limit of detection (<0.44 µg/L). The prevalent polymer components in the samples were PE (0.10 – 1.17 µg/L), PET (0.06 – 0.91 µg/L), PP (0.04 – 0.79 µg/L), and PS (0.06 – 0.53 µg/L) nanoplastics. The presented analytical method offers an accurate means to identify, quantify, and monitor nanoplastics in complex environmental and potable water samples. It fills gaps in our understanding of nanoplastic pollution levels, providing a valuable methodology and crucial reference data for future studies. [Display omitted] • Presentation of a methodology for the quantification of nanoplastics in water. • Mass concentrations of nanoplastics across water samples were assessed by Pyr-GC/MS. • Eight nanoplastics (PMMA, Nylon 6, Nylon 66, PC, PS, PET, PP, PE) quantified. • PE, PET, PP and PS were the predominant nanoplastics. • Total nanoplastics concentrations of between 0.04 and 1.17 µg/L in water samples. [ABSTRACT FROM AUTHOR]

The concerns on the carriers of microplastics (MPs) on co-existing pollutants in aquatic environments are sharply rising in recent years. However, little is known about their interactions on the colonization of microbiota, especially for the spread of pathogens and antibiotic resistance genes (ARGs). Therefore, this study aimed to investigate the influences on the propagation of ARGs in sediments by the co-exposure of different MPs and sulfamethoxazole (SMX). The results showed that the presence of MPs significantly enhanced the contents of total organic carbon, while having no effects on the removal of SMX in sediments. Exposure to SMX and MPs obviously activated the microbial carbon utilization capacities based on the BIOLOG method. The propagation of ARGs in sediments was activated by SMX, which was further promoted by the presence of polylactic acid (PLA) MPs, but significantly lowered by the co-exposed polyethylene (PE) MPs. This apparent difference may be attributed to the distinct influence on the antibiotic efflux pumps of two MPs. Moreover, the propagation of ARGs may be also dominated by microbial carbon metabolism in sediments, especially through regulating the carbon sources of carboxylic acids, carbohydrates, and amino acids. This study provides new insights into the carrier effects of MPs in sediments. [Display omitted] • Both PLA- and PE-MPs enhanced the TOC concentrations in sediments. • SMX induced higher microbial carbon metabolism, which was inhibited by the co-exposed MPs. • MPs and SMX enhanced microbial richness and diversity, but lowered metabolic function. • MPs and SMX could propagate ARGs through regulating the antibiotic efflux pumps. • Carbon metabolism may be the predominant factor affecting ARGs propagation in sediments. [ABSTRACT FROM AUTHOR]

The idea that it is a risk to promote biodegradable mulch films on a large scale is becoming established at academic level based on a series of articles similar in approach and conclusions. However, a critical analysis shows that the results do not justify the alarmist tones. The negative effects of hand-cut pieces of virgin material added in pots at concentrations up to 714 times the application doses are ascribed to the "accumulation" and "contamination" of "residues" and "debris" of biodegradable plastics. Yet, no accumulation and no contamination of biodegradable microplastics has actually been shown. No Predicted Environmental Concentration was established, thus the use of the term risk is inappropriate. The hypothesis of transient phytotoxicity of organic matter under decomposition i.e., an artificial outcome of the experimental scheme used, was not considered. A scrupulous approach to terminology is very important for the quality of communication and for the development of innovations. Scientific communication is a delicate process in which and to avoid hyperbole, there must be strict logical and lexical consistency between results and conclusions. Guidelines on the communication of the results of studies on biodegradable mulch must be developed to avoid the spread of unjustified concerns. [Display omitted] • The number of publications and obtained quotes affects academic career and grants. • Hype is increasingly used to make scientific articles more visible and quoted. • The results are shown in a negative way using hyperbole to raise attention. • This situation creates bias in publications and baseless concerns in public opinion. • Guidelines are urgently needed to improve scientific communication. [ABSTRACT FROM AUTHOR]

Biodegradable plastics (BPs) are more prone to generate harmful microplastics (MPs) in a short time, which have always been ignored. Oxygenated functional group formation is considered to be a key indicator for assessing microplastic formation, while it is difficult to characterize at a very early stage. The micromechanical properties of the aging plastic during the formation of the MPs are highly influenced by the evolution of oxygen-containing functional groups, however, their relationship has rarely been revealed. Herein, we compared changes in the physicochemical properties of BPs and non-degradable plastic bags during aging in artificial seawater, soil, and air. The results showed that the oxidation of plastics in the air was the most significant, with the most prominent oxidation in BPs. The accumulation of carbonyl groups leads to a significant increase in the micromechanical properties and surface brittleness of the plastic, further exacerbating the formation of MPs. It was also verified by the FTIR, 2D-COS, AFM, and Raman spectroscopy analyses. Furthermore, the increased adhesion and roughness caused by oxygen-containing functional groups suggest that the environmental risks of BPs cannot be ignored. Our findings suggest that the testing of micromechanical properties can predicate the formation of the MPs at an early stage. [Display omitted] • Biodegradable plastics are more prone to form MPs in natural conditions. • Accumulation of oxygen-containing functional groups induces the micromechanical forces changes and the formation of MPs. • The micromechanical behavior changes are correlated to the formation of MPs. • Micromechanical properties can be a new method to predict the formation of MPs. [ABSTRACT FROM AUTHOR]

Microplastics are recognized as an emerging critical issue for the environment. Here an innovative chemical approach for the treatment of microplastics is proposed, based on an oxidative process that does not require any direct energy source (irradiation or heat). Linear low-density polyethylene (LLDPE) was selected as target commodity polymer, due to its widespread use, chemical inertness and inefficient recycling. This route is based on a hybrid material coupling titanium oxide with a bio-waste, rosin, mainly constituted by abietic acid, through a simple sol-gel synthesis procedure. The ligand-to-metal charge transfer complexes formed between rosin and Ti4+ allow the generation of reactive oxygen species without UV irradiation for its activation. In agreement with theorical calculations, superoxide radical ions are stabilized at ambient conditions on the surface of the hybrid TiO 2. Consequently, an impressive degradation of LLDPE is observed after 1 month exposure in a batch configuration under indirect daylight, as evidenced by the products revealed by gas chromatography-mass spectrometry analysis and by chemical and structural modifications of the polymer surface. In a context of waste exploitation, this innovative and sustainable approach represents a promising cost-effective strategy for the oxidative degradation of microplastics, without producing any toxic by-products. [Display omitted] • A new hybrid material (T- Abi) was synthesized by a waste-to-wealth approach. • Rosin bio-waste acts as ligand to Ti4+ forming charge-transfer complex. • O 2 •– radicals are generated on T- Abi without the need for any energetic source. • A new oxidative degradation process using indirect daylight is exploited. • After 1 month, alkanes, alcohols, esters are the LLDPE degradation by-products. [ABSTRACT FROM AUTHOR]

The presence of microplastics (MPs) in large quantities in the aqueous environment significantly affects the degradation process of water pollution. Still, the interaction between MPs and pollutants during photocatalytic degradation has not been studied. Here, a soluble BiOCl-OH semiconductor-organic framework (BOCH-SOF) was prepared from xylitol, and the polystyrene (PS) MPs' effect on the photocatalytic degradation of tetracycline (TC) was investigated. It was found that the appropriate number of PS can promote TC degradation and also change degradation products and pathways. At the same time, the presence of TC can effectively enhance PS aging and reduce the molecular weight of PS. This indicates that BOCH-SOF produces a synergistic effect in treating the combined pollution of TC and PS. Through free radical analysis and density functional theory calculations, it was proposed that PS and TC can complement each other. A certain concentration and size of PS can promote the conversion of Bi(III) to Bi and enhance charge separation and radical generation; the TC can change the interfacial charge distribution and free radical depletion, extend the light absorption in the system, and the PS and TC work together to ultimately achieve the synergistic degradation of the TC and the aging PS. This paper provides an in-depth analysis of the mechanism of the effect of MPs on the photocatalytic degradation of antibiotics, which is significant in controlling the combined pollution of MPs and associated pollutants in the water environment. [Display omitted] • BOCH-SOF significantly improved the photocatalytic degradation activity of TC. • The PS promotes the trans of Bi(III) to Bi and enhances the radical generation. • TC changes charge distribution and ROS depletion, extending the light absorption. • PS and TC work together to achieve the synergist of the TC removal and the PS age. [ABSTRACT FROM AUTHOR]

The widespread use of plastic materials, owing to their several advantageous properties, has resulted in a considerable increase in plastic consumption. Consequently, the production of primary and secondary microplastics has also increased. To identify, categorize, and quantify microplastics, several analytical methods, such as thermal analysis and spectroscopic methods, have been developed. They generally offer little insight into the size and shape of microplastics, require time-consuming sample preparation and classification, and are susceptible to background interference. Herein, we created a macroscale hyperspectral Raman method to quickly quantify and characterize large volumes of plastics. Using this approach, we successfully obtained Raman spectra of five different types of microplastics scattered over an area of 12.4 mm × 12.4 mm within just 550 s and perfectly classified these microplastics using a machine learning method. Additionally, we demonstrated that our system is effective for obtaining Raman spectra, even when the microplastics are suspended in aquatic environments or bound to metal-mesh nets. These results highlight the considerable potential of our proposed method for real-world applications. [Display omitted] • We obtained a hyperspectral Raman image of microplastics covering an area of 12.4 mm × 12.4 mm in just 10 min. • Machine learning model and image processing techniques were applied to analyze microplastics, sea sand, and dust effectively. • Our system successfully provided Raman images of microplastics in aquatic environments and on metal mesh nets. [ABSTRACT FROM AUTHOR]

Plastic pollution, particularly microplastics, poses a significant environmental challenge. This study aimed to address the urgent need for sustainable solutions to manage plastic waste. The degradation of polyethylene microplastics (PEMPs) and nylon 6,6 microplastics (NMPs) were investigated using bacterial culture isolates, isolated from a municipal landfill site and identified through 16 S rDNA as well as metagenomics techniques.The study demonstrated for the first time along with degradation mechanism. The isolates identified as Achromobacter xylosoxidans and mixed culture species in dominance of Pulmonis sp. were used to degrade PEMPs and NMPs. Achromobacter xylosoxidans reduced microplastic's dry weight by 26.7% (PEMPs) and 21.3% (NMPs) in 40 days, while the mixed culture achieved weight reductions of 19.3% (PEMPs) and 20% (NMPs). The release of enzymes, laccase and peroxidases revealed C-C bond cleavage and reduced polymer chain length. The thermal studies (TGA and DSC) revealed changes in the thermal stability and transition characteristics of microplastics. The structural alterations on PEMPs and NMPs were recorded by FTIR analysis. Byproducts such as alkanes, esters, aromatic compounds and carboxylic acids released were identified by GC-MS. These results suggest the effectiveness of bacterial isolates in degrading PEMPs and NMPs, with potential for sustainable plastic waste management solutions. [Display omitted] • Metagenomics reveals plastic degrading soil bacterial community. • Laccase and peroxidase plays significant role in microplastic degradation. • Thermal studies demonstrated thermal stability and degradation of PEMPs and NMPs. • Identification of alkanes, esters and aromatic, byproducts through GC-MS analysis. [ABSTRACT FROM AUTHOR]

Over recent years, biodegradable polymers have been proposed to reduce environmental impacts of plastics for specific applications. The production of polyhydroxyalkanoates (PHA) by using diverse carbon sources provides further benefits for the sustainable development of biodegradable plastics. Here, we present the first study evaluating the impact of physical, chemical and biological factors driving the biodegradability of various tailor-made PHAs in the marine environment. Our multidisciplinary approach demonstrated that the chemical structure of the polymer (i.e. the side chain size for short- vs. medium-chain PHA) which was intrinsically correlated to the physico-chemical properties, together with the specificity of the biofilm growing on plastic films (i.e., the associated 'plastisphere') were the main drivers of the PHA biodegradation in the marine environment. [Display omitted] • Marine biodegradation is much higher on scl- than mcl- PHA. • PHA types mainly influence biodegradation. • Identification of distinct bacteria involved in scl- or mcl- PHA biodegradation. [ABSTRACT FROM AUTHOR]

Microplastic (MP) pollution has become a major global concern due to the widespread use and discharge of plastics into the environment. However, very few studies have assessed the potential variations in the toxicity of MPs according to their shape and size. Therefore, our study sought to identify the biotoxic effects of spherical, fiber-shaped, and fragment-shaped polyethylene terephthalate MPs of different sizes at different concentrations on the Mediterranean mussel Mytilus galloprovincialis. The survival rate after exposure to small-sized MPs was lower than that observed for the larger type MPs. Bioaccumulation of MPs was different depending on the exposure periods and MP shapes. Interestingly, the fiber-shaped MPs underwent morphological modifications in the mussel body upon uptake. MP exposure also increased the global DNA methylation levels (i.e., an epigenetic signature), expression of the microbiota immunity-related toll-like receptor gene, and alteration of the gut microbial composition in the mussel. These findings indicated that MPs of different shapes and sizes at different concentrations can alter the bioaccumulation sensitivity of mussels according to the exposure periods, and the balance of gut immunity and epigenetic process. Furthermore, our results demonstrated that MPs of different shapes, particularly fiber types, can undergo morphological modification in mussel tissues, thus posing a hazardous threat. [Display omitted] • Small types of fiber and fragment MPs have lower survival rate than large type MPs. • Bioaccumulation of MPs were different depending on the exposure time and MP types. • Morphological (length) changes were observed in fiber MPs upon uptake into mussel tissues. • MPs induced upregulations of global DNA methylation, which is an epigenetic signature. • Long-term exposures of MPs disrupted microbial communities and immunity in mussel gut. [ABSTRACT FROM AUTHOR]

Environmental microplastics (MPs) constitute various sizes, polymers, and shape components. In estuaries, such differences are related to the reliability of assessing the seaward fate of MPs, aggregation hotspots, and ecological risks. This study sets the MP particle mass gradient using the shape factor and size probability density function to categorically estimate the MP load in the surface layer of the Yangtze River Estuary (YRE), which is the largest contributor of plastics to the sea. During the high plastic input period in July, the optimized estimated MP load through the surface layer of the YRE was 9766 kg/month, which was overestimated by 821 kg/month based on the empirical average particle mass. While tracking MP transport classified by shape and polymer type, the resuspension of MPs that accumulate in the intertidal zone cannot be neglected. The average relative error of the simulation was as low as 19.6% after including the abovementioned factors. Finally, the simulation results of the sensitive regions were extracted to assess the new MP risk index, which considers shape, abundance, and polymer type. By introducing these essential tools, this study helps to understand the fate of riverine MPs entering estuaries, where valuable opportunities for removing MPs exist before they spread to the oceans. [Display omitted] • Shape and polymer classification for MP simulation is considered in an estuary. • The riverine MP load and transport was modified by size PDF and new shape factor. • Riverine load and MP source from intertidal zone control the model accuracy in summer. • An MP risk index covering abundance, shape, and polymer characteristics is proposed. [ABSTRACT FROM AUTHOR]

To address the challenging issues of waste plastic pollution and petroleum shortage, we report herein a pulse pressurized catalytic pyrolysis process where polyethylene is continuously converted into aromatics using HZSM-5 catalyst incorporated with hydrated SiO 2. Pressurization improves the activity of single-pulse pyrolysis of polyethylene by 14.42%. In contrast to the linear decrease of BTEXS relative yield with a K value of − 0.23 under non-pressurized conditions, pressurization results in a notable stability in the latter stage, characterized by a K value of only − 0.063. Comprehensive catalyst characterization demonstrates that pressurization promotes the release of water from hydrated SiO 2 , enabling HZSM-5 to effectively undergo dealumination and obtain suitable acidity and pore structure, and ultimately enhancing the resistance to carbon deposition. In summary, pressurization improves both pyrolysis activity and catalysis stability, offering a promising strategy for the high-value utilization of waste plastics. [Display omitted] • Pulse pressurized catalytic pyrolysis process for plastic upcycling is proposed. • Pressurization improves single pulse pyrolysis activity of polyethylene by 14.42%. • Pressurization improves overall catalytic stability of HZSM-5. • Pressurization promotes dealumination of HZSM-5 with synergism of hydrated SiO 2. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are ubiquitous pollutants that significantly threaten organisms and ecosystems. Constructed wetlands (CWs), a nature-based treatment technology, can effectively remove MPs from wastewater. However, the responses of CWs when exposed to MPs remain unclear. In this study, lab-scale vertical flow constructed wetlands (VFCWs) were installed for receiving polystyrene (PS) MPs at concentrations of 100 μg/L and 1000 μg/L. The results showed that exposure to PS-MPs has no effects on COD and TP removal in VFCWs, but TN removal decreased by 3.69–5.37 %. Further investigation revealed that PS-MPs significantly impacted microbial communities and metabolic functions. The abundances of predominant nitrifiers (Nitrospira and Nitrosomonas) and denitrifiers (Nakamurella , Bradyrhizobium , and Bacillus) in VFCWs were significantly reduced, aligning with the responses of key enzymes. The presence of PS-MPs also decreased nitrogen removal by plant uptake, leading to decreased plant biomass and chlorophyll by 39.32–48.75 % and 5.92–32.19 %, respectively. Notably, > 90 % removal rates were observed for PS-MPs within VFCWs. In addition to PS-MPs interception by VFCWs substrate, the increase of released benzenes indicated that the PS-MPs biodegradation occurred. Such insights are vital for developing sustainable solutions to mitigate MPs' adverse effects on ecosystems. [Display omitted] • PS-MPs negatively impacted complete nitrification and denitrification modules in VFCWs. • PS-MPs reduced plant biomass by 39.32–48.75 % in VFCWs. • Over 90 % of PS-MPs were removed via substrate interception and biodegradation in VFCWs. • PS-MPs underwent biodegradation, forming benzene intermediates. [ABSTRACT FROM AUTHOR]