Mixture Of Polyethylene Research Articles

Detection of micro- and nanoplastic particles in leafy green vegetables by SERS coupled with gold-silver core-shell nanoparticles.

Asensitive and accurate method has been developedfor detecting and quantifying polystyrene (PS) and polyethylene (PE) in food samples using surface-enhanced Raman spectroscopy (SERS) with a simple preparation process. Themethod is designed to effectively detect and quantify mixtures of these polymers in varying ratios within the food matrix. By employing gold-silver core-shell nanoparticles (Au@Ag NPs) as the enhancing substrate, the SERS method demonstrated superior sensitivity in detecting trace amounts of micro- and nanoplastic particles (MNPs). For 1-µm PS microparticles, the limit of detection (LOD) values range from 12 to 50 mg/L or mg/kg in water, spinach, and kale, while for 100-nm PS nanoparticles, the LOD values range from 18 to 47 mg/L or mg/kg. For 1-µm PE microparticles, the LOD values range from 173 to 416 mg/L or mg/kg in the same matrices, whereas for 65-nm PE nanoparticles, the values range from 446 to 744 mg/L or mg/kg. The mixtures of PS and PE in varying ratios were also tested, with both plastics detectable even at trace levels, emphasizing the method's precision in detecting plastic contaminants. These findings highlight the potential of SERS as a powerful tool for monitoring MNP contamination in food products by detecting both individual plastics and their mixtures, enabling precise quantification of contamination and contributing to improved food safety.

Fate and effects of an environmentally relevant mixture of microplastics in simple freshwater microcosms

Most studies assessing the effects of microplastics (MPs) on freshwater ecosystems use reference materials of a certain size, shape, and polymer type. However, in the environment, aquatic organisms are exposed to a mixture of different polymers with different sizes and shapes, resulting in different bioaccessible fractions and effects. This study assesses the fate and effects of an environmentally relevant mixture of high-density polyethylene (HDPE) fragments, polypropylene (PP) fragments, and polyester (PES) fibres in indoor freshwater microcosms over 28 days. The MP mixture contained common polymers found in freshwater ecosystems, had a size range between 50 and 3887 µm, and was artificially aged using a mercury lamp. The invertebrate species included in the microcosms, Lymnea stagnalis (snail) and Lumbriculus variegatus (worm), were exposed to four MP concentrations: 0.01, 0.05, 0.1 and 1 % of sediment dry weight. MPs fate was assessed by performing a balance of the MPs in the surface water, water column, and sediment after a stabilization period and at the end of the experiment. Sedimentation rates per day were calculated (2.13 % for PES, 1.46 % for HDPE, 1.87 % for PP). The maximum size of MPs taken up by the two species was determined and compared to the added mixture and their mouth size. The size range taken up by L. variegatus was smaller than L. stagnalis and significantly different from the size range in the added mixture. The No Observed Effect Concentrations (NOECs) for the reproduction factor of L. variegatus and the number of egg clutches produced by L. stagnalis were 0.01 % and 0.1 % sediment dry weight, respectively. The EC10 and EC50 for the same endpoint for L. stagnalis were 0.25 % and 0.52 %, respectively. This study shows that current MP exposure levels in freshwater sediments can result in sub-lethal effects on aquatic organisms, highlighting the importance of testing MP mixtures.

Characterization of pyroplastics from the North Atlantic

This work describes for the first time the presence of pyroplastics in the Canary Islands (Spain). A total of 300 pyroplastics, identified between 2021 and 2024 in three beaches of the island of Tenerife, present mainly grey and dark colors, a mean weight of 6.8 ± 13.4 g and mean dimensions of 34.2 ± 17.0 mm (X), 24.5 ± 12.2 mm (Y) and 14.4 ± 6.4 (Z). A wide variety of encapsulated and semi-encapsulated materials were also found in the pyroplastics matrix, such as rocks, wood, charcoal and unmelted plastic inclusions. Fourier-transform infrared spectroscopy analysis revealed that polyethylene and polypropylene were the main types of plastic found, 61.3 % and 33.6 %, respectively. However, an important number of pyroplastics composed of more than one polymer were also found, coexisting even mixtures of polyester and polyethylene or polyethylene and styrene-ethylene-butylene-styrene in the same matrix. X-ray fluorescence spectroscopy analysis revealed the presence of a wide range of elements, being remarkable the high concentration of some heavy metals such as Pb and Cr, registering mean concentration values of 205.3 ± 6.3 mg·kg−1 and 51.1 ± 8.9 mg·kg−1, respectively. A good correlation was also found for these two metals in a total of 22 pyroplastics, which could be indicative of the presence of PbCrO4 as additive, widely used in the plastic industry for its bright yellow color, but currently regulated and restricted due to its harmful effects on human and environment health. Also noteworthy is the large variety of remains of marine organisms identified attached to the surface of the pyroplastics, such as algae, bryozoans, arthropods and molluscs, among others, which could indicate that these formations may act as a transport vector for such marine organisms.

Mixing screw design and high density polyethylene toughening modification for recycled polypropylene based on screw 3D printing

AbstractThe recycling of waste plastics primarily involves physical modification and the addition of modifiers, often utilizing equipment such as twin‐screw extruders for miscible modification. Considering the widespread use of single‐screw 3D printing, improving the mixing efficiency of the single‐screw is crucial to achieve a “one‐stop” recycling modification that is suitable for 3D printing. This paper introduces a 3D printer equipped with a mixing screw (MS) and compares it with a conventional screw (CS). We conduct numerical simulations to investigate the pressure build‐up capacity, velocity streamline distribution, and the mixing effect of the MS. The mechanical properties, thermal characteristics, and molecular orientation of the recycled Polypropylene (rPP) and high density polyethylene (HDPE) mixture are investigated through experiments. The results show that the MS provides more effective elongational flows compared to the CS by breaking down the reinforcing materials into smaller particles. Additionally, toughening and modification experiments are performed on rPP and HDPE. The composites treated with the MS showed improved elongation at break (increased by ~111%), a stable melt crystallization temperature, and an enhanced mixing effect. This study on single‐screw 3D printers lays the groundwork for streamlining the plastic recycling process and increasing the reuse rate of recycled plastics.

Classical and reactive simulations of plastic co-pyrolysis: Effects of polystyrene and its fragments on product yields, aggregation, and reaction mechanisms

Mixtures of polyethylene (PE), polypropylene (PP), polystyrene (PS), and their fragments such as ethylbenzene (EB) and linear alpha olefin (LAO) are simulated at different ratios using classical and reactive force fields. Using all-atom models validated by calculating conformations and diffusivities of differently sized PE melts in agreement with experiments, simulations are performed at 450 or 513 K that mimics a low temperature under the thermal co-pyrolysis condition, showing that the decomposition of PE into LAO influences densities and diffusivities of PE, to an extent dependent on PE lengths. In PE/PP/PS simulations, PS polymers aggregate at PS concentrations of 20 wt% or higher, leading to the separation between PS and other polymers. With the inclusion of EB that are assumed to be decomposed from PS, polymers do not aggregate. To understand reaction mechanisms, reactive simulations of PE and PS are performed, showing more heavy oil and less gas products at higher PS concentrations, in agreement with experiments, because PS fragments such as benzene, EB, and methylbenzene bind to PE and end up in heavy or light oils. In particular, the transfer of H radicals between PE and PS not only prevents further decomposition of polymers but also yields free radicals of polymers that can expedite co-pyrolysis. These findings help explain experimental observations regarding the effect of PS on liquid and gas product yields and suggest the optimal PS concentration without aggregation under the thermal co-pyrolysis condition, interpreted by reaction mechanisms of the transfer of H radicals and benzene fragments.

Hierarchical HZSM-5 catalysts enhancing monocyclic aromatics selectivity in co-pyrolysis of wheat straw and polyethylene mixture

The limitation in bio-oil quality hampers its further utilization in the fuel or chemical industry. This study employed a combination of tetra propylammonium hydroxide (TPAOH) and NaOH solutions for HZSM-5 desilication to enhance the yield of monocyclic aromatic hydrocarbons in the catalytic co-pyrolysis of wheat straw with polyethylene. Results revealed hierarchical HZSM-5, prepared with equal mole concentrations of NaOH and TPAOH, exhibited optimal catalytic performance. The bio-oil from this process had an aromatic content of 72 %, with monocyclic aromatic hydrocarbons (MAHs) constituting 56.26 %. Further optimization was achieved through iron modification of hierarchical HZSM-5. The addition of 0.5 % iron-modified hierarchical HZSM-5 increased the aromatic hydrocarbons to 80.57 %, with BTX compounds (benzene, toluene, and xylene) reaching a selectivity of 61.9 %. This approach reduced polycyclic aromatic hydrocarbons (PAHs), contributing to less coke formation, presenting a promising method for high-quality bio-oil.

Increasing microplastic exposure had minimal effects on fatty acid composition in zooplankton and yellow perch in a large, in-lake mesocosm experiment

Using 10 m diameter mesocosms in a Canadian boreal lake, we investigated the effects of microplastic (MP) exposure on the body weight and diet of yellow perch ( Perca flavescens) and the fatty acid composition of yellow perch and zooplankton. We exposed the aquatic ecosystem within seven mesocosms for 10 weeks to a mixture of polyethylene, polystyrene, and polyethylene terephthalate fragments, ranging in nominal addition concentrations from 6 to 29 240 particles L−1 (although realized water column concentrations were lower), as well as two negative controls. Increasing MP exposure did not affect yellow perch body weight (growth) or diet, or the overall fatty acid composition of yellow perch muscle or zooplankton. Results were highly variable across mesocosms. Despite high levels of MP ingestion by yellow perch, we did not find evidence of MPs leading to food dilution or any other effect where we could anticipate impacts on food web structure.

Modified electrode configuration of the free-fall tribo-electrostatic separator for the recovery of polyethylene and polypropylene flakes from shredded packaging waste

Free-fall tribo-electrostatic separators have long been used for sorting granular plastic wastes. The aim of this paper is to propose a modified configuration of the electrode system of such a separator and validate its effectiveness for processing a mixture of polyethylene (PE) and polypropylene (PP) flakes originating from the processing of packaging waste at GRANUPLAST Company, Jassans-Riottier, France. The mixture to be treated is not homogeneous and consisted of roughly 2/3 PE and 1/3 PP. The granular mixture samples were charged by triboelectric effect in a fluidized bed device, and then introduced into a laboratory-scale free-fall electrostatic separator. Preliminary tests were conducted to ascertain the mass of the mixture to be introduced in the fluidized bed and the duration of the charging process. Better results were obtained with the modified electrode configuration of the free-fall electrostatic separator. Thus, from 100 g of mixed flakes, 98.2% of PE and 96.6% of PP were recovered with purities of 99.1% and 98%, respectively. In addition, numerical modeling of the PP and PE particles trajectory was performed to simulate the behavior of charged particles in the standard and modified electrode configurations. Work is in progress for the industrial implementation of this tribo- electrostatic separation technology.

Single exposure of food-derived polyethylene and polystyrene microplastics profoundly affects gut microbiome in an in vitro colon model

Microplastics (MPs) are widespread contaminants highly persistent in the environment and present in matrices to which humans are extensively exposed, including food and beverages. MP ingestion occurs in adults and children and is becoming an emerging public health issue. The gastrointestinal system is the most exposed to MP contamination, which can alter its physiology starting from changes in the microbiome. This study investigates by an omic approach the impact of a single intake of a mixture of polyethylene (PE) and polystyrene (PS) MPs on the ecology and metabolic activity of the colon microbiota of healthy volunteers, in an in vitro intestinal model. PE and PS MPs were pooled together in a homogeneous mix, digested with the INFOGEST system, and fermented with MICODE (multi-unit in vitro colon model) at loads that by literature correspond to the possible intake of food-derived MPs of a single meal. Results demonstrated that MPs induced an opportunistic bacteria overgrowth (Enterobacteriaceae, Desulfovibrio spp., Clostridium group I and Atopobium − Collinsella group) and a contextual reduction on abundances of all the beneficial taxa analyzed, with the sole exception of Lactobacillales. This microbiota shift was consistent with the changes recorded in the bacterial metabolic activity.

STUDY ON THE INFLUENCE OF RATING CHARGE ON TEMPERATURE AND PHASE BEHAVIOR OF STABILIZED MATRIX WAX-BASED THERMAL STORAGE

The rating charge characteristic is crucial for the heat energy storage, particularly for low-temperature system which uses paraffin wax. The influence of different rating charge causes severe temperature fluctuation, which is undesirable for the heat system. It is affected by unstable phase transformation, reducing the heat distribution and makes the average rating charge insufficient. In this work, the fluctuation can be minimized by adding polyethylene plastic as phase stabilizer for the wax. The polyethylene is added by ratio of weight of 15% from the total mass of 134 grams. Each material is mixed in the liquid state, stirred and molded into the apparatus. The phase transition evaluation is performed, showing the mixture indicates an additional transition peak after the principal phase transformation, ranging between 15.26 °C – 19.34 °C (melting) and 11.98 °C – 9.45 °C (freezing). The steady operation makes the lowest rating variation is only 0.3 °C/min, which is obtained by the mixture of wax and polyethylene. In the same rating charge, the wax has rating variation of 2.9 °C/min, signifying the effect of unsteady melting transition. It clearly demonstrates the addition of polyethylene for the mixture promotes a better phase transformation under various rating charge, maintaining the effective temperature distribution for the heat storage.

Assessment of heating rate and mixing ratio on the synergistic effects of co-pyrolysis of pine sawdust and high-density polyethylene

The co-pyrolysis of biomass and plastics presents a promising approach for generating hydrocarbon fuels and high-value chemicals while addressing environmental pollution concerns. This study investigates the pyrolysis process by examining mixtures of pine sawdust (PS) and high-density polyethylene (HDPE) with varying mass proportions and heating rates using analytical methods including thermogravimetric analysis and differential scanning calorimetry (TGA-DSC), thermogravimetry coupled with Fourier transform infrared spectroscopy (TG-FTIR) coupled analysis, pyrolysis gas chromatography-mass spectrometry (Py-GC-MS) and kinetic analysis. The study highlights the impact of heating rate on product distribution, with significant changes observed when the biomass ratio is at 30 %. Moreover, the addition of high-density polyethylene leads to an increase in polyol content in the liquid product. Analysis of product types reveals that plastics act as “hydrogen donors,” supplying hydrogen to biomass during co-pyrolysis, thus reducing oxygen chemicals. Results from the kinetic analysis show that the activation energy for co-pyrolysis is lower than individual pyrolysis, also indicating a synergistic effect. Overall, this research provides insights into the synergistic benefits of co-pyrolysis and establishes a theoretical foundation for advancing co-pyrolysis technology.

Efficiencies of Thermophilic Bacteria Species in Degrading Biodegradable Low-density Polyethylene Mixtures in Aquatic Ecosystems

The study examined the efficiencies of bacteria thermophiles responsible for the depolymerization of biodegradable Low-Density Polyethylene (LDPE) blends in two aquatic environments to suggest model bacteria species that could be used for reducing the accumulation of single-use LDPE in both marine and freshwater ecosystems. Each of the biodegradable LDPE, polyethylene, and cellulose was placed in respirometry jars filled with 500 mls of the freshwater and marine water respectively in a randomized design of 4 by 2 by 3 following the American Standard Testing and Materials (ASTM) procedure. To identify the bacteria species, bacterial isolation was done using pour plate and streak methods. The bacteria species were identified by morphological, biochemical, and molecular methods. The thermophilic bacteria species were confirmed by sequencing to be Bacillus cereus, Pseudomonas species among others. The results revealed that the bacteria isolates on LDPE were responsible for the biodegradation processes of the LDPE. This study concluded that Bacillus cereus and Pseudomonas species have the bioremediation potentials to break down single-use biodegradable Low-Density Polyethylene (LDPE) in aquatic environments within six (6) months.

Catalytic Deconstruction of Ethylene Vinyl Acetate Copolymer and Polyethylene Mixtures via Hydroconversion: Challenges and Solutions

Catalytic Deconstruction of Ethylene Vinyl Acetate Copolymer and Polyethylene Mixtures via Hydroconversion: Challenges and Solutions

Investigation of waste LDPE with Pongamia pinnata seed for sustainable resource recovery: Thermodynamics, Kinetics and artificial neural network modeling for co-pyrolysis potential

Pyrolysis conversion offers the advantages of significant waste reduction and potential energy recovery. This work examined the potential of combining plastic and agricultural wastes as pyrolysis feedstocks. The mixture of waste low-density polyethylene and Pongamia pinnata seeds was analysed using differential and thermogravimetric methods. In addition to the Coats-Redfern (CR) method, Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO), Friedman (FRM), and Kissinger (KN) model-free methods were also applied to calculate the kinetic parameters. The apparent activation energy (Ea) calculation demonstrated that the co-pyrolysis conversion required Ea values of 125–154 kJ mol−1. The artificial neural network (ANN) model was considered to validate thermogravimetric data. The R2 values were near unity in training, validation, and testing conditions, with the minimum possible value for mean square error obtained for the considered heating rates. The Pongamia pinnata seeds and waste plastic mixture could surely be utilized to lessen environmental degradation, add value to leftover seeds and waste low-density polyethylene by extracting fuel for transportation and other commercial activities, and produce industrial chemicals, as found through the kinetic modelling, thermodynamic parameters, and ANN modelling.

The promoting effects of soil microplastics on alien plant invasion depend on microplastic shape and concentration

Both alien plant invasions and soil microplastic pollution have become a concerning threat for terrestrial ecosystems, with consequences on the human well-being. However, our current knowledge of microplastic effects on the successful invasion of plants remains limited, despite numerous studies demonstrating the direct and indirect impacts of microplastics on plant performance. To address this knowledge gap, we conducted a greenhouse experiment involving the mixtures of soil and low-density polyethylene (LDPE) microplastic pellets and fragments at the concentrations of 0, 0.5 % and 2.0 %. Additionally, we included Solidago decurrens (native plant) and S. canadensis (alien invasive plant) as the target plants. Each pot contained an individual of either species, after six-month cultivation, plant biomass and antioxidant enzymes, as well as soil properties including soil moisture, pH, available nutrient, and microbial biomass were measured. Our results indicated that microplastic effects on soil properties and plant growth indices depended on the Solidago species, microplastic shapes and concentrations. For example, microplastics exerted positive effects on soil moisture of the soil with native species but negative effects with invasive species, which were impacted by microplastic shapes and concentrations, respectively. Microplastics significantly impacted catalase (P < 0.05) and superoxide dismutase (P < 0.01), aboveground biomass (P < 0.01), and belowground/aboveground biomass (P < 0.01) of the native species depending on microplastic shapes, but no significant effects on those of the invasive species. Furthermore, microplastics effects on soil properties, nutrient, nutrient ratio, and plant antioxidant enzyme activities contributed to plant biomass differently among these two species. These results suggested that the microplastics exerted a more pronounced impact on native Solidago plants than the invasive ones. This implies that the alien invasive species displays greater resistance to microplastic pollution, potentially promoting their invasion. Overall, our study contributes to a better understanding of the promoting effects of microplastic pollution on plant invasion.

Agglomeration of coal and polyethylene mixtures during fixed-bed co-gasification

The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene (up to 20 wt% fraction) in a laboratory reactor. The work aims to study the agglomeration process during the heating and oxidation of the mixtures. The measurement results (gas composition, pressure drop) provide indirect information on the dynamics of thermal decomposition and structural changes in the fuel bed. We have shown that the interaction between polyethylene and a coal surface leads to the formation of dense agglomerates, in which the molten polymer acts as a binder. Clinkers form as a result of interfacial interactions between components and filtration flow rearranging. The hydrogen/carbon ratio in the solid residue of coal-polyethylene co-gasification increases from 0.07–0.2 to 1.11, indicating the formation of stable hydrocarbon compounds on the carbon surface. The conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to agglomeration in mixtures of coal with polyethylene.

Catalytic hydrogenolysis of polypropylene and polyethylene mixtures: Effect of temperature on liquid alkane components

This study explored the interactions between different polyolefins using a commercial Ru/C catalyst-mediated hydrogenolysis of polypropylene (PP), low-density polyethylene (LDPE), and their mixtures. The effects of the mass ratio of polyolefins to the catalyst, temperature, pressure and time on the yield of products and the internal components of liquid alkane products were studied, and the optimum conditions for solo plastic hydrogenolysis were determined. The highest liquid alkane yields of PP (46.70 %) and LDPE (70.70 %) were obtained at 250 and 210 °C, respectively. Further, the interactions between PP and LDPE during co-hydrogenolysis were observed. The temperature had a significant influence on the gaseous and liquid products, and we proposed a two-step hydrogenolysis reaction process for a mixture of polyethylene with polypropylene conducted at various temperatures. Co-hydrogenolysis provides a high-value utilization path for polyolefins that are difficult to separate during recovery.

Influence of structure-forming agent on rheological properties of polymer mixture based on low and high density polyethylene

The paper considers the effect of a structure-forming agent (titanium dioxide) on the rheological characteristics of a polymer mixture based on low and high density polyethylene, taken in a 50/50 ratio. The titanium dioxide concentration was 1 wt%. The rheological behavior of melts of polymer composites was studied using a CEAST MF50 capillary rheometer (Instron, Italy) at temperatures of 190, 210, 230, 250 °С and loads of 3.8, 5.0, 10.0, 12.5, and 21.6 kg. The effect of temperature and shear stress on the regularity of changes in effective viscosity and shear rate has been established. According to the Arrhenius – Frenkel – Eyring model, the activation energy of the viscous flow of composites is determined. The “apparent” activation energy of the viscous flow varies within 16.04–33.10 kJ/mol for the initial polyethylene mixture and in the range of 6.96–33.10 kJ/mol for composites modified with a structurant based on a mixture of low and high density polyethylene. A universal temperature-invariant characteristic of the viscosity properties of polymeric materials has been constructed, which makes it possible, by extrapolating this dependence to the region of high shear rates, to predict the technological mode of their processing by injection molding and extrusion.

Municipal Plastic Waste Recycling through Pyrogasification

Conventional mechanical recycling technologies cannot recycle all types and amounts of generated plastic waste. Pyrolysis can convert these municipal mixed plastic streams into products with significant calorific value, which are likely to be used as energy sources. The present work describes a technology used to expand the portfolio of technical approaches to drive plastics circularity, i.e., thermochemical recycling. A base case scenario considered a capacity of 1.000 kg/h of municipal plastic waste, consisting of a mixture of polypropylene (PP), polystyrene (PS), polyethylene (PE), and plastic associated with paper, which were converted into non-condensable gases, oil, and char through a pyrogasification system. Based on mass and energy balances and experimental data from the literature, a total of 199.4 kg (48 MJ/kg) of liquid fuel and 832.85 kg (16 MJ/kg) of gas could be obtained with no need for external heating sources. The thermal requirement for the pyrolysis of 1.000 kg of municipal plastic waste (1.316 MJ) was supplied by the gasification of a fraction of the produced pyrolysis oil and gases. This feasibility analysis confirmed the technical adequacy of the proposed technology, which that will be further complemented by a technoeconomic study of the proposed solution.

Hidden threats in the plastisphere: Carbapenemase-producing Enterobacterales colonizing microplastics in river water

Carbapenem resistance poses a significant burden on healthcare systems worldwide. Microplastics (MPs) have emerged as potential contributors to antibiotic resistance spread in the environment. However, the link between MPs and carbapenem resistance remains unexplored. We investigated the prevalence of carbapenem-resistant bacteria colonizing MPs placed in a river. Three replicates of a mixture of polypropylene (PP), polyethylene (PE) and polyethylene terephthalate (PET) and of PET alone were placed both upstream and downstream a wastewater treatment plant (WWTP) discharge. Carbapenem-resistant Enterobacterales (CRE) were further characterized by phenotypic tests and whole-genome sequencing. The abundance of carbapenem-resistant bacteria on MPs increased significantly downstream the WWTP. Their prevalence was higher in the MPs mixture compared to PET alone. CRE strains colonizing MPs included Klebsiella pneumoniae (n = 3), Klebsiella quasipneumoniae (n = 3), Raoultella ornithinolytica (n = 2), Enterobacter kobei (n = 1) and Citrobacter freundii (n = 1), most (n = 8) recovered after the WWTP discharge. All strains exhibited at least one of the tested virulence traits (biofilm formation at 37 °C, haemolytic activity and siderophore production), were multi-drug resistant and carried carbapenemase-encoding genes [blaKPC-3 (n = 5), blaGES-5 (n = 2) or blaKPC-3 + blaGES-5 (n = 3)]. Uncommon phenotypes of resistance to imipenem/relebactam (n = 3) and ceftazidime/avibactam (n = 2) were observed. Two blaKPC−3-positive K. pneumoniae successfully transfer this gene trough conjugation. Genome analysis predicted all strains as human pathogens. The blaKPC−3 was associated with the Tn4401d transposon on a pBK30683-like plasmid in most of the isolates (n = 7). The blaGES-5 was mostly linked to class 3 integrons. A K. pneumoniae strain belonging to the outbreak-causing high-risk clone ST15 carried both blaKPC-3 and blaCTX-M-15. Two K. quasipneumoniae isolates carried the plasmid-mediated colistin resistance gene mcr-9. Our results underscore the role of MPs as vectors for CRE dissemination, particularly following WWTPs discharges. MPs may act as carriers, facilitating the dissemination of carbapenemase-encoding genes and potentially contributing to increased CRE incidence in the environment.