Plasticized Poly Vinyl Chloride Research Articles

Effect of Scratches on Mechanical Properties and Impermeability of PVC-P Geomembranes

Plasticized polyvinyl chloride (PVC-P) geomembranes (GMBs) are susceptible to physical scratches due to improper construction in water conservancy projects. Axial tensile tests and permeability tests were carried out to investigate the mechanical properties and impermeability of PVC-P GMBs with scratches under various combinations of scratch angles, lengths, and depths. This was achieved by evaluating the break strength, break elongation, Young’s modulus, and permeability coefficient. The results demonstrated that physical scratches weaken the mechanical properties of PVC-P GMBs, and interactions among the influencing factors were observed. The influence of scratches on the break elongation and break strength outweighed that on Young’s modulus, with scratch depth exerting the most significant effect on the mechanical properties under identical conditions. The scratches on PVC-P GMBs should be minimized in practice, while those without penetrating cracks along the thickness direction and tensile deformation have negligible effects on impermeability. The failure threshold of PVC-P GMBs with scratches was determined, along with the scratch depths, angles, and lengths affecting the operation of the project. This provides a reference for assessing whether PVC-P GMBs with scratches jeopardize the safety of projects.

Comprehensive Review on Bio-Based Treatments for Polyvinyl Chloride Plastic.

Polyvinyl chloride (PVC) plastics are widespread around the globe, and each year, thousands of tons of PVC end up in the environment in the form of micro-/nanoplastics. Literature has reported extensively on the biodegradation of its PVC additives/plasticizers; however, bio-based treatment approaches for its polymers have been scanty. The current review has discussed elaborately all possible PVC degradation processes and the toxicity challenges faced during its mitigation. This review has also delineated and assessed all physical, chemical, and biological approaches reported for PVC treatments. All the biodeterioration, biocatalysis, and biodegradation mechanisms reported for PVC have been comprehensively discussed. Recent advances have also been highlighted like the direct application of invertebrate species and selective enzymes like peroxidases, alkane monooxygenase, and laccase during PVC treatment. Insights of functional genomes/genes and OMICS have been recommended, which might help predict and address any future issues during the mitigation of PVC pollution in the environment.

From the end to the beginning: Obtaining and evaluation of flexible PVC produced via chemical recycling of post-consumer PET

Di(2-ethylhexyl) terephthalate (DEHTP) is a promising substitute for dioctyl phthalate (DOP, banned in certain countries) as a polyvinyl chloride (PVC) plasticizer. This research endeavors to present findings about the synthesis of DEHTP through the depolymerization of polyethylene terephthalate (PET) with 2-ethyl-1-hexanol, the production and assessment of PVC formulated with this plasticizer, and a comparative analysis with PVC compounded using commercial plasticizers (DOP and DEHTP). Approximately 200 post-consumer PET bottles underwent chemical recycling under various conditions, leading to complete depolymerization (99%) following a six-hour reaction at 300°C. The plasticizers were characterized by infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, and gas chromatography coupled to mass spectrometry. The flexible PVCs were tensile and hardness tested and submitted to dynamic mechanical and thermogravimetric analyses. The resulting plasticizer exhibited properties analogous to commercial DEHTP, producing flexible PVC with even better properties. For instance, the activation energy of the dehydrochlorination reaction of the flexible PVC produced with DHETP from depolymerization was 3.3% to 16.2% higher than those produced with commercial plasticizers.

Amphiphilic poly(methacryloxyethyl sulfobetaine)-block-poly(ε-caprolactone) blended polyvinyl chloride plastics: Study on the Relationship between molecular structure and antibiofouling properties

The blending of amphiphilic copolymers with plastics is an important method for preparing antibiofouling medical plastics. However, enhancing the enrichment of amphiphilic copolymers on the plastic surface, thereby improving the antibiofouling performance of the plastics remain challenging tasks. Herein, we designed and synthesized a series of amphphilic copolymers, denoted as PSB-b-nPCL. These copolymers possess similar chemical compositions but exhibit distinct topological structures. Antibiofouling flexible polyvinyl chloride (PVC) films were prepared by blending PSB-b-nPCL with PVC. These films showed excellent mechanical and thermal properties. X-ray photoelectron spectroscopy, water contact angle and hydration capacity tests demonstrated that PSB-b-nPCL which bearing more PCL blocks were more prone to migrating to the film surface, thereby enhancing the film’s hydrophilicity. Furthermore, anti-protein adsorption, anti-bacterial and anti-platelet adhesion properties of the films were investigated. It was found that topological structure can obviously affect the antibiofouling performance of films. Specifically, films blended with PSB-b-nPCL containing more PCL blocks exhibited superior performance. The optimal blended film achieved a reduction of 96.4% in bovine albumin adsorption, 82% in platelet adhesion, and nearly complete inhibition of bacterial adhesion. We anticipate that the strategy presented in this work will pave a new path for the development of high performance antibiofouling plastics.

Toxic Cargo: How Rail Transport of Vinyl Chloride Puts Millions at Risk, an Analysis One Year After the Ohio Train Derailment.

On February 3, 2023, five train cars containing 887,400 pounds of vinyl chloride, the key building block for polyvinyl chloride (PVC) plastic, derailed and burned, setting off a major environmental health disaster that sickened area residents and first responders, killed wildlife, and contaminated East Palestine, Ohio and surrounding communities. OxyVinyls is the largest vinyl chloride monomer producer in the United States and the third-largest PVC supplier in the United States. How much of this hazardous chemical is transported every year, and how many people are put at risk? To better understand the magnitude of this hazard, we established the most likely rail routes for shipping of vinyl chloride from two OxyVinyls plants in Texas to four PVC factories in New Jersey, Illinois, and Ontario. We estimate that up to 36 million pounds of vinyl chloride travels on more than 200 rail cars across nearly 2,000 miles of US railways at any given moment. Over a year, an estimated 8,595 rail cars carry approximately 1.5 billion pounds of vinyl chloride from OxyVinyls to these plastics plants. The rail shipment of vinyl chloride to make PVC plastic puts more than three million people at risk. We estimate more than three million people live, and about 670,000 children attend more than 1500 schools, within one mile of the train route between Texas and New Jersey.

Digging Deeper: Assessing the Impact of Limestone Exploitation and Use Worldwide

Limestone has always been widely used in various sectors, thus having significant economic and environmental impacts. The quarrying process is, on the one hand, essential, but on the other, harmful to the environment and people’s health, therefore, the challenge is finding a balance. This review explores the multifaceted nature of limestone, a sedimentary rock predominantly composed of calcium carbonate. The formation of limestone, along with its various types and global occurrence, is discussed to provide a basic understanding. The diverse applications of limestone range from historical uses in ancient monuments to contemporary roles in cement production, plasticized polyvinyl chloride (PVC), and soda–lime glass. The discussion extends to post-mining solutions, showcasing successful rehabilitation and innovative repurposing of former quarries into useful infrastructures, wildlife habitats, and cultural spaces. This article draws attention to the importance of sustainable practices and technological developments to balance resource use with environmental conservation. Ultimately, it emphasizes the need for responsible limestone quarrying and proactive rehabilitation strategies to ensure that no permanent ecological problems will occur.

Effects of dual plasticizers for improved PVC gel-based varifocal tiny lens

Abstract Electroactive polyvinyl chloride (PVC) gel-based varifocal lenses are attractive due to their excellent transparency, simple fabrication, compact structure, and good flexibility. In this work, dibutyl adipate (DBA) and propylene carbonate (PC) were utilized to plasticize PVC for fabricating transparent, soft, and flexible gels by solvent casting method. The PVC gels were characterized by various experimental techniques to investigate their optical, electrical, mechanical, and thermal properties. Further, the PVC gels were examined to construct a compact plano-convex tiny lens structure for varifocal lens application under electrical stimulation. The work revealed that the introduction of a co-plasticizer PC improves the overall dielectric property as well as transparency of the PVC gels. The observed enhancement in dielectric constant of the PC incorporated gels increased up to 6 times of the only DBA plasticized PVC gel (D9) while the transmittance value is ~5% higher than that of D9 gel. Moreover, the optimal ratio of DBA and PC in PVC gel was found to be 8.6: 0.4: 1 (wt %) and the optimized D8.6P0.4 gel induces better actuation properties resulting in improved focal length variation for the developed lens. The proposed adaptive tiny lens could change its focal length from 3 mm to 20.5 mm with increasing input voltage from 0 V to 1000 V. The developed tiny lens exhibited excellent optical characteristics including fast response speed and good stability. Moreover, this study broadens the scope for property tuning strategies for the EAP design and application.

The Effect of Dicarboxylic Acid Structure on the Plasticizing Ability of Its Ester.

Polyvinyl chloride (PVC) belongs to the most widely used group of thermoplastics. Most of the market for PVC products belongs to plasticized compositions. Plasticizers are the most demanded additives in the polymer industry. Environmental problems and the identified toxicity of the plasticizer di(2-ethylhexyl) phthalate (DEHP) stimulate the restriction of its use and contribute to the development of alternative plasticizers. As a possible replacement for phthalates, esters of dicarboxylic acids are known to provide reduced toxicity and high frost resistance to the resulting compositions. In this regard, esters of dicarboxylic acids and ethoxylated alcohols were obtained and their compatibility with polyvinyl chloride was investigated. The plasticizing effect of the esters obtained was evaluated. The thermomechanical characteristics of PVC compositions containing the developed plasticizers were studied, the glass transition temperature was determined, and the areas of the glassy and highly elastic state of the plastics were identified. It was shown that the chemical structure of dicarboxylate used as a plasticizer determines the important technological and operational characteristics of the PVC plastics obtained. Dibutoxyethyl sebacate (DBES) has the best plasticizing effect among the synthesized esters. The expansion of the highly elastic state area for PVC samples containing this ester exceeded the industrial plasticizers DEHP and di(2-ethylhexyl) adipate (DOA). The indicators of the critical temperature of dissolution of PVC in the esters under study suggest ensuring their low migration from PVC plastics.

Selection of Plastic-Binding DNA Aptamers for Microplastics Detection.

Plastics are critical materials for modern technological applications, yet environmental contamination by microplastics has become a growing concern. In this study, DNA aptamers were isolated for two of the most abundant plastic materials: polyvinylchloride (PVC) and polystyrene (PS). These aptamers contain approximately 90 % cytosine and thymine but only 10 % purine content. Among them, the PVC-1 aptamer binds to PVC with a six-fold higher capacity than a random sequenced DNA. Among the tested plastic materials, PVC and PS exhibited the highest specific binding capacity. Using fluorophore-labeled PVC-1 aptamer, PS/PVC microplastics as low as 1 mg were detected, and the aptamer was selective for microplastics over other environmentally relevant materials, such as silica. Molecular dynamics simulations indicated that the aptamer attempted to maximize contact with the plastic surface for adsorption. This plastic-binding aptamer is expected to find applications in environmental monitoring and has fundamental implications for surface-binding aptamers.

Photothermal Upcycling of Waste Polyvinyl Chloride Plastics.

Upgrading the most difficult-to-recycle waste polyvinyl chloride remains a significant challenge due to the potential formation of highly toxic substances, such as polychlorinated biphenyls. Here, we introduce a paradigm shift with a mild photothermal dechlorination-carbonization process that converts waste polyvinyl chloride plastics into valuable carbon materials. Through detailed techno-economic assessment (TEA) process modeling, based on recycling 96,000 tons of plastics, we demonstrate that utilizing clean solar energy for photothermal conversion can save approximately 2.34 × 1012 kJ electricity and reduce the carbon footprint by 261,912.2 tons compared to traditional thermal-driven methods, offering clear environmental benefits. Notably, this photothermal recycling method can process more than 10 types of postconsumer and mixed waste polyvinyl chloride plastics, yielding carbon materials that exhibit excellent performance as components in sodium-ion energy storage batteries. Photothermal catalytic recycling of plastics thus emerges as a green and sustainable technology with promising applications.

New Antimicrobial Materials Based on Plasticized Polyvinyl Chloride for Urinary Catheters: Preparation and Testing.

Given the constant increased number of nosocomial infections in hospitals, especially associated with prolonged usage of inserted medical devices, our work aims to ameliorate clinical experience and promote faster healing of patients undergoing urinary catheterization by improving the properties of medical devices materials. Within this research, nine different composites were prepared based on polyvinyl chloride, using three different plasticizers (di-(2-ethylhexyl) phthalate, Proviplast 2646, and Proviplast 2755), and two different antimicrobial additives containing silver nanoparticles. The prepared materials were analyzed, and their physicochemical properties were determined: water absorption, relative density, plasticizer migration, hydrophobicity/hydrophilicity by contact angle measurement, Shore A hardness, tensile strength, and elongation at break. Structure and morphology were also investigated by means of FTIR, SEM, and EDX analyses, and thermal (TG-DSC) and biological properties were evaluated. The most important aspects of obtained results are showing that plasticizer migration was significantly reduced (to almost zero) and that the usage of antimicrobial additives improved the materials' biocompatibility. Thus, based on the concluded favorable properties, the obtained materials can be further used for catheter development. Pressure-flow studies for different sizes and configurations are the next steps toward advanced in vivo and clinical trials.

High rubber elasticity and thermal conductivity in plasticized polyvinyl chloride film with flame retardancy and smoke suppression properties

AbstractFor hydrogenated nitrile‐butadiene rubber (HNBR) modified polyvinyl chloride (PVC), magnesium hydroxide and antimony trioxide are frequently employed as flame retardants. Fume silica is thought to be useful reinforced agent for rubber as well as efficient flame retardant for polymer‐based composites. The plasticized PVC and HNBR blend in this work were combined with three fillers mentioned above to create rubber‐plastic composites that performed well overall, with a notable improvement in combustion. The limiting oxygen index of the composites increased from 23.7% to 33.8% with no droplets falling during combustion, the smoke density rating decreased from 23.8% to 7.9%, and the maximum smoke density dropped from 95.5% to 15.5%. The cone calorimetry test findings revealed that the three fillers simultaneously prevented the emission of smoke and heat from combustion. High thermal conductivity is typically linked to excellent flame retardancy. The thermal conductivity of composites rose from 0.193 to 0.583 W m−1 K−1 with the addition of fillers. Furthermore, the low glass transition temperature and permanent set of improved composites reflect its softness and rubber elasticity. Thermogravimetric analysis was used to examine the thermal stability of the composites in nitrogen and air, and the results indicated the addition of fillers improved the thermal stability.

The Impact of Plasticizer Levels in Hardening PVC Plastic

This paper provides a detailed investigation into the effects of Trioctyl Trimellitate (TOTM) plasticizer levels on the hardness of Polyvinyl Chloride (PVC) materials. The study reveals an inverse correlation between the level of TOTM plasticizer and the hardness of PVC, with an increase in TOTM levels leading to a decrease in hardness. This trend is consistent across various PVC samples, despite minor variations. The role of plasticizers in determining the physical and mechanical properties of PVC is further explored, emphasizing their function in reducing PVC’s crystallinity, thereby producing a clearer and more flexible material. This research contributes to the understanding of how plasticizers can be used to tailor the properties of PVC, leading to the development of two distinct types of PVC: Flexible PVC, which contains a plasticizer, and Rigid PVC, which does not. The findings underscore the importance of plasticizers in material design and engineering, offering valuable insights for future applications.

Natural sea water and artificial sea water are not equivalent in plastic leachate contamination studies

Background Plastic contamination is one of the concerns of our age. With more than 150 million tons of plastic floating in the oceans, and a further 8 million tons arriving to the water each year, in recent times the scientific community has been studying the effects these plastics have on sea life both in the field and with experimental approaches. Laboratory based studies have been using both natural sea water and artificial sea water for testing various aspects of plastic contamination, including the study of chemicals leached from the plastic particles to the water. We set out to test this equivalence, looking at the leaching of heavy metals form plastic particles. Methods We obtained leachates of polyvinyl chloride plastic pre-production nurdles both in natural and artificial sea water and determined the elements in excess from untreated water by Inductively coupled plasma – optical emission spectrometry. We then used these different leachates to assess developmental success in the tunicate Ciona intestinalis by treating fertilised eggs through their development to hatched larvae. Results Here we report that chemical analysis of polyvinyl chloride plastic pre-production pellet leachates shows a different composition in natural and artificial sea water. We find that the zinc leaching from the plastic particles is up to five times higher in natural seawater than in artificial seawater, and this can have an effect in the toxicological studies derived. Indeed, we observe different effects in the development of C. intestinalis when using leachates in natural or artificial sea water. We also observe that not all artificial sea waters are suitable for studying the development of the tunicate C. intestinalis. Conclusions Our results show that, at least in this case, both types of water are not equivalent to produce plastic leachaetes and suggest that precaution should be taken when conclusions are derived from results obtained in artificial sea water.

Production of Bio-plasticized Polyvinyl Chloride (PVC) Films Synthesized from Microalgae (Chlorella vulgaris)

Abstract Bio-based plasticizers for PVC films are being explored to replace conventional phthalate-based plasticizers due to the threats they pose to human health and the environment. In the present study, fatty acids from Chlorella vulgaris were extracted via Microwave-assisted Extraction and were epoxidized using esterification and transesterification reactions in a magnetically stirred reactor to produce EFAME plasticizer. FTIR Analysis determined the presence of an epoxy group as the peak C=O stretch (1739.79 cm−1) was detected. PVC films were synthesized at different concentrations of EFAME (30%, 40%, and 60%). At 40% of EFAME, the PVC exhibited high displacement in the tensile strength and elongation at break test, which was used as a basis to produce PVC-A, PVC-B, and PVC-C, and was compared to phthalate-plasticized PVC film, PVC-D. SEM-EDX Analysis verified the presence of PVC and EFAME in the plasticized PVC films as Carbon, Oxygen, and Chlorine elements were detected. PVC A had the lowest weight loss percentage at 40.96% indicating it has developed high migration resistance among the extraction mediums used. DSC analysis confirmed the plasticizing effect of EFAME as the glass transition temperature of bioplasticized PVC films decreased. Using One-way ANOVA, the physicochemical tests of PVC films plasticized with EFAME showed significantly better results than PVC films plasticized by DOP. Thus, the present study indicates that the bio-based plasticizer derived from C. vulgaris is a better and a potential alternative for phthalates in plasticizing PVC films.

Impact of hydrophobic and hydrophilic surface properties on Pseudomonas aeruginosa adhesion in materials used in mineral water wells

Microbiologically contaminated water is a significant source of infections in humans and animals, with Pseudomonas aeruginosa (PSA) being particularly concerning due to its ability to thrive in water environments and its resistance to many disinfectants. Therefore, this study investigates the adhesion potential of PSA strains on various materials used in mineral water extraction wells, focusing on hydrophobic and hydrophilic properties. Mineral water samples were collected from three wells (P-01, P-07, and P-08) within the Guarani Aquifer System and Fractured Aquifer System (SAF) in Brazil. The physicochemical properties of the water, including concentrations of Sr (strontium), Fe (iron), Si (silicon), SO4 2− (sulfate ions), Cl− (chloride ions), and ORP (oxidation-reduction potential), were analyzed. Results indicated higher PSA adhesion on hydrophobic materials, particularly high-density polyethylene (HDPE) and geomechanically plasticized polyvinyl chloride (PVC). Multiple correlation analyses revealed positive correlations between PSA adhesion on hydrophilic materials and Sr, Fe, Si, SO4 2−, and Cl− concentrations. Conversely, ORP negatively correlated with bacterial adhesion on PVC surfaces, suggesting higher ORP values reduced PSA attachment. These findings highlight the importance of water composition and material properties in influencing bacterial adhesion and potential biofilm formation in mineral water extraction systems.

Revolutionizing sensing technologies: Crafting a green, ultra-sensitive bismuth optical sensor via fixation of 5-(2′,4′-dimethyl-phenylazo)-6-hydroxypyrimidine-2,4-dione on PVC membrane

An innovative and exceptionally responsive optical sensing device engineered to selectively identify Bi(III) ions in water-based solutions. The sensing component, 5-(2′,4′-dimethylphenylazo)-6-hydroxypyrimidine-2,4-dione (DMPAHPD), is incorporated into a plasticized polyvinyl chloride (PVC) membrane. The sensor demonstrates an exceptional selectivity for Bi(III) within a broad dynamic range spanning from 7.5 × 10−10 to 4.2 × 10−5 M at pH 2.25. Notably, it achieves lower quantification and detection limits of 7.25 × 10−10 and 2.15 × 10−10 M, respectively. The optode membrane’s response to Bi(III) proves to be entirely reversible, demonstrating remarkable selectivity for Bi(III) ions over a diverse range of other cations and anions. The sensor exhibits favorable performance characteristics, including good reversibility, a wide dynamic range, a prolonged lifespan, sustained response stability over the long term, and high reproducibility. This visual chemical sensor exhibits potential for real-world usage, offering consistent outcomes when assessing Bi(III) levels in matrices such as water, soil, plants, biological and synthetic mixtures. Importantly, the sensor’s performance is comparable to corresponding data achieved from inductively coupled plasma atomic emission spectroscopy (ICP-AES).

Method of calculation of temperature parameters and servic life of cable lines with a voltage of 10 kV

RELEVANCE. The paper presents a method for calculating the temperature parameters and service life of cable lines (CL) with a voltage of 10 kV for various types of insulation and operating conditions. Dependencies have been developed that are recommended for clarifying the parameters of the CL, taking into account different operating modes. The results of the study can be used for practical application and will contribute to reducing the number of accidents resulting from thermal breakdowns of CL due to incorrect selection of CL parameters.PURPOSE. To investigate the temperature parameters of 10 kV CL, taking into account various methods of laying them and load factors for the climatic conditions of the Republic of Tatarstan.METHODS. Methods for calculating the temperature parameters of CL and their service life, methods of statistical data processing, and methods for approximating functions are used. The ELCUT software package is used to visualize the results obtained during calculations. results. The results of calculations of the temperature parameters of 10 kV CL with paper-impregnated insulation (BPI), polyvinyl chloride plastic (PVC) insulation and polyethylene (PE) insulation during their laying in air, in the ground, in the ground in a pipe, taking into account the load coefficients of cable lines, are presented. The results of calculations of the service life of the CL are shown. The values of the optimal load coefficients of the CL are determined to reduce the rate of thermal aging of insulation under various operating conditions. conclusion. The results of the conducted research and calculations can be used to evaluate and select the optimal load of 10 kV CL at the stages of operation and design of power supply systems.

Quantification of tungsten in real samples spectrophotometrically using optical sensor

A new methodology was devised to detect tungsten in aqueous samples, employing a sensor membrane crafted by physically incorporating a tungsten-selective compound, 5-(2 -bromophenylazo)-6-hydroxypyrimidine-2,4-dione (BPAHPD), into a plasticized poly(vinyl chloride). The addition of Triton X-114 was observed to be advantageous in augmenting the absorption of HWO4− ions from the liquid phase into the membrane phase, thereby amplifying sensor absorption intensity. The method established a linear dynamic span of 15–350 ng mL−1 for W(VI), exhibiting a notable correlation coefficient of 0.9992. Quantification and detection limits were determined to be 14.85 and 4.45 ng mL−1, correspondingly, under optimized conditions. The Sandell responsiveness and molar absorptivity were calculated at 0.0455 ng cm−2 and 4.04 × 108 L/mol cm−1, respectively. The sensor demonstrated superb selectivity, as demonstrated by the negligible influence of potential interfering species. Statistical analyses, encompassing variance ratio F-tests and Student’s t-tests, indicated no substantial differences. The efficacy of the methodology was authenticated through the scrutiny of genuine samples, with statistical comparison to the ICP-AES method.

Combined effects of polyvinyl chloride or polypropylene microplastics with cadmium on the intestine of zebrafish at environmentally relevant concentrations

Cadmium (Cd) is a common additive in polyvinyl chloride (PVC) and polypropylene (PP) plastics. Aquatic organisms were inevitably co-exposed to PVC/PP microplastics (MPs) and Cd, but their combined toxicity is still unknown. In this study, adult zebrafish were exposed to 200 μg/L MPs (PVC or PP) and 10 μg/L Cd alone or in combination for 28 days to investigate their toxicity and mechanisms. Results showed that combined exposure with PVC/PP enhanced the Cd accumulation in the zebrafish intestine. Subsequently, toxicology analyses showed that both PVC and PP possessed synergistic toxicity with Cd, manifested by the exfoliation and necrosis of intestinal epithelial cells, and increased levels of interleukin-1β (IL-1β), superoxide dismutase (SOD) and malondialdehyde (MDA). PP exhibited a stronger synergistic effect than PVC. Integration of non-targeted metabolomics and 16S rRNA gene sequencing revealed that combined exposure to PVC and Cd induced intestine toxicity mainly through bile acid (BA) biosynthesis, fructose (Fru) and mannose (Man) metabolism, and pentose phosphate pathway (PPP). The combined exposure of PP and Cd induced toxicity through the arginine (Arg) and glutathione (GSH) metabolisms. Meanwhile, combined exposure of PVC/PP and Cd increased the abundance of intestinal Proteobacteria and pathogen Vibrio, and decreased the abundance of Gemmobacter. These changes indrectly promoted the synergistic toxicity of PVC/PP and Cd through metabolites, such as indole-3-pyruvate (IPyA), chenodeoxycholic acid (CDCA), and cholic acid (CA). These findings highlighted that more attention should be paid to the toxicity of chemicals at environmentally relevant concentrations, particularly those co-existing with MPs.