RESUMO
Plastic pollution has become a major environmental concern, and various plastic polymers are used daily. A study was conducted to examine the toxic effects of polyethylene terephthalate (PET) nanoplastics (NPLs) on Drosophila melanogaster. We have successfully synthesized PET NPLs and characterized using DLS, Zeta potential, TEM, HRTEM, SAED, XRD, FTIR, and Raman spectroscopy to gain crucial insights into the structure and properties. We fed PET NPLs to Drosophila to assess toxicity. ROS was quantified using DCFH-DA and NBT, and the nuclear degradation was checked by DAPI staining. Quantification of protein and activity of antioxidant enzymes like SOD, catalase depicted the adverse consequences of PET NPLs exposure. The dorsal side of the abdomens, eyes, and wings were also defective when phenotypically analyzed. These results substantiate the genotoxic and cytotoxic impact of nanoplastics. Notably, behavioral observations encompassing larval crawling and climbing of adults exhibit normal patterns, excluding the presence of neurotoxicity. Adult Drosophila showed decreased survivability, and fat accumulation enhanced body weight. These findings contribute to unraveling the intricate mechanisms underlying nanoplastic toxicity and emphasize its potential repercussions for organismal health and ecological equilibrium.
Assuntos
Drosophila melanogaster , Polietilenotereftalatos , Animais , Drosophila melanogaster/efeitos dos fármacos , Polietilenotereftalatos/toxicidade , Polietilenotereftalatos/química , Espécies Reativas de Oxigênio/metabolismo , Nanopartículas/toxicidade , Nanopartículas/química , Comportamento Animal/efeitos dos fármacos , Larva/efeitos dos fármacosRESUMO
To address two current issues in evaluating the toxicity of microplastics (MPs) namely, conflicting results due to species specificity and the ecological irrelevance of laboratory data, this study conducted a 10-day exposure experiment using a microalgal community comprising three symbiotic species. The experiment involved virgin and Benzo[a]pyrene-spiked micron-scale fibers and fragments made of polyethylene terephthalate (PET) and polypropylene (PP). The results showed that, from a physiological perspective, environmentally relevant concentrations of micron-scale MPs decreased saccharide accumulation in microalgal cells, as confirmed by ultrastructural observations. MPs may increase cellular energy consumption by obstructing cellular motility, interfering with nutrient uptake, and causing sustained oxidative stress. Additionally, MPs and adsorbed B[a]P induced DNA damage in microalgae, potentially further disrupting cellular energy metabolism. Ecologically, MPs altered the species abundance in microalgal communities, suggesting they could weaken the ecological functions of these communities as producers and affect ecosystem diversity and stability. This study marks a significant advancement from traditional single-species toxicity experiments to community-level assessments, providing essential insights for ecological risk assessment of microplastics and guiding future mechanistic studies utilizing multi-omics analysis.
Assuntos
Metabolismo Energético , Microalgas , Microplásticos , Microplásticos/toxicidade , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Metabolismo Energético/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Polipropilenos/toxicidade , Polipropilenos/química , Dano ao DNA/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Benzo(a)pireno/metabolismo , Polietilenotereftalatos/química , Polietilenotereftalatos/toxicidade , Tamanho da Partícula , Estresse Oxidativo/efeitos dos fármacosRESUMO
Wastewater treatment plants play a crucial role in controlling the transport of pollutants to the environment and often discharge persistent contaminants such as synthetic microplastic fibers (MFs) to the ecosystem. In this study, we examined the fate and toxicity of polyethylene terephthalate (PET) MFs fabricated from commercial cloth in post-disinfection secondary effluents by employing conditions that closely mimic disinfection processes applied in wastewater treatment plants. Challenging conventional assumptions, this study illustrated that oxidative treatment by chlorination and ozonation incurred no significant modification to the surface morphology of the MFs. Additionally, experimental results demonstrated that both pristine and oxidized MFs have minimal adsorption potential towards contaminants of emerging concern in both effluents and alkaline water. The limited adsorption was attributed to the inert nature of MFs and low surface area to volume ratio. Slight adsorption was observed for sotalol, sulfamethoxazole, and thiabendazole in alkaline water, where the governing adsorption interactions were suggested to be hydrogen bonding and electrostatic forces. Acute exposure experiments on human cells revealed no immediate toxicity; however, the chronic and long-term consequences of the exposure should be further investigated. Overall, despite the concern associated with MFs pollution, this work demonstrates the overall indifference of MFs in WWTP (i.e., minor effects of disinfection on MFs surface properties and limited adsorption potential toward a mix of trace organic pollutants), which does not change their acute toxicity toward living forms.
Assuntos
Microplásticos , Águas Residuárias , Poluentes Químicos da Água , Microplásticos/toxicidade , Microplásticos/química , Adsorção , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Águas Residuárias/química , Desinfecção , Humanos , Eliminação de Resíduos Líquidos/métodos , Polietilenotereftalatos/química , Polietilenotereftalatos/toxicidadeRESUMO
Polyethylene terephthalate (PET) is a common plastic widely used in food and beverage packaging that poses a serious risk to human health and the environment due to the continual rise in its production and usage. After being produced and used, PET accumulates in the environment and breaks down into nanoplastics (NPs), which are then consumed by humans through water and food sources. The threats to human health and the environment posed by PET-NPs are of great concern worldwide, yet little is known about their biological impacts. Herein, the smallest sized PET-NPs so far (56 nm) with an unperturbed PET structure were produced by a modified dilution-precipitation method and their potential cytotoxicity was evaluated in Saccharomyces cerevisiae. Exposure to PET-NPs decreased cell viability due to oxidative stress induction revealed by the increased expression levels of stress response related-genes as well as increased lipid peroxidation. Cell death induced by PET-NP exposure was mainly through apoptosis, while autophagy had a protective role.
Assuntos
Estresse Oxidativo , Polietilenotereftalatos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Polietilenotereftalatos/toxicidade , Nanopartículas/toxicidade , Apoptose/efeitos dos fármacos , Microplásticos/toxicidade , Peroxidação de Lipídeos/efeitos dos fármacosRESUMO
Microplastics (MPs) are a major concern in marine ecosystem because MPs are persistent and ubiquitous in oceans and are easily consumed by marine biota. Although many studies have reported the toxicity of MPs to marine biota, the toxicity of environmentally relevant types of MPs is little understood. We investigated the toxic effects of fragmented polyethylene terephthalate (PET) MP, one of the most abundant MPs in the ocean, on the marine rotifer Brachionus koreanus at the individual and molecular level. No significant rotifer mortality was observed after exposure to PET MPs for 24 and 48 h. The ingestion and egestion assays showed that rotifers readily ingested PET MPs in the absence of food but not when food was supplied; thus, there were also no chronic effects of PET MPs. In contrast, intracellular reactive oxygen species levels and glutathione S-transferase activity in rotifers were significantly increased by PET MPs. Transcriptomic and metabolomic analyses revealed that genes and metabolites related to energy metabolism and immune processes were significantly affected by PET MPs in a concentration-dependent manner. Although acute toxicity of PET MPs was not observed, PET MPs are potentially toxic to the antioxidant system, immune system, and energy metabolism in rotifers.
Assuntos
Microplásticos , Polietilenotereftalatos , Espécies Reativas de Oxigênio , Rotíferos , Poluentes Químicos da Água , Animais , Rotíferos/efeitos dos fármacos , Polietilenotereftalatos/toxicidade , Microplásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Glutationa Transferase/metabolismo , Glutationa Transferase/genética , Testes de Toxicidade , Transcriptoma/efeitos dos fármacos , Metabolômica , Ingestão de Alimentos , MultiômicaRESUMO
BACKGROUND: During inhalation, airborne particles such as particulate matter ≤ 2.5 µm (PM2.5), can deposit and accumulate on the alveolar epithelial tissue. In vivo studies have shown that fractions of PM2.5 can cross the alveolar epithelium to blood circulation, reaching secondary organs beyond the lungs. However, approaches to quantify the translocation of particles across the alveolar epithelium in vivo and in vitro are still not well established. In this study, methods to assess the translocation of standard diesel exhaust particles (DEPs) across permeable polyethylene terephthalate (PET) inserts at 0.4, 1, and 3 µm pore sizes were first optimized with transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV-VIS), and lock-in thermography (LIT), which were then applied to study the translocation of DEPs across human alveolar epithelial type II (A549) cells. A549 cells that grew on the membrane (pore size: 3 µm) in inserts were exposed to DEPs at different concentrations from 0 to 80 µg.mL- 1 ( 0 to 44 µg.cm- 2) for 24 h. After exposure, the basal fraction was collected and then analyzed by combining qualitative (TEM) and quantitative (UV-VIS and LIT) techniques to assess the translocated fraction of the DEPs across the alveolar epithelium in vitro. RESULTS: We could detect the translocated fraction of DEPs across the PET membranes with 3 µm pore sizes and without cells by TEM analysis, and determine the percentage of translocation at approximatively 37% by UV-VIS (LOD: 1.92 µg.mL- 1) and 75% by LIT (LOD: 0.20 µg.cm- 2). In the presence of cells, the percentage of DEPs translocation across the alveolar tissue was determined around 1% at 20 and 40 µg.mL- 1 (11 and 22 µg.cm- 2), and no particles were detected at higher and lower concentrations. Interestingly, simultaneous exposure of A549 cells to DEPs and EDTA can increase the translocation of DEPs in the basal fraction. CONCLUSION: We propose a combination of analytical techniques to assess the translocation of DEPs across lung tissues. Our results reveal a low percentage of translocation of DEPs across alveolar epithelial tissue in vitro and they correspond to in vivo findings. The combination approach can be applied to any traffic-generated particles, thus enabling us to understand their involvement in public health.
Assuntos
Material Particulado , Alvéolos Pulmonares , Emissões de Veículos , Humanos , Emissões de Veículos/toxicidade , Emissões de Veículos/análise , Células A549 , Material Particulado/toxicidade , Material Particulado/análise , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Tamanho da Partícula , Microscopia Eletrônica de Transmissão , Polietilenotereftalatos/química , Polietilenotereftalatos/toxicidade , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análiseRESUMO
The environmental presence of nano- and micro-plastic particles (NMPs) is suspected to have a negative impact on human health. Environmental NMPs are difficult to sample and use in life science research, while commercially available plastic particles are too morphologically uniform. Additionally, this NMPs exposure exhibited biological effects, including cell internalization, oxidative stress, inflammation, cellular adaptation, and genotoxicity. Therefore, developing new methods for producing heterogenous NMPs as observed in the environment is important as reference materials for research. Thus, we aimed to generate and characterize NMPs suspensions using a modified ultrasonic protocol and to investigate their biological effects after exposure to different human cell lines. To this end, we produced polyethylene terephthalate (PET) NMPs suspensions and characterized the particles by dynamic light scattering and scanning electron microscopy. Ultrasound treatment induced polymer degradation into smaller and heterogeneous PET NMPs shape fragments with similar surface chemistry before and after treatment. A polydisperse suspension of PET NMPs with 781 nm in average size and negative surface charge was generated. Then, the PET NMPs were cultured with two human cell lines, A549 (lung) and HaCaT (skin), addressing inhalation and topical exposure routes. Both cell lines interacted with and have taken up PET NMPs as quantified via cellular granularity assay. A549 but not HaCaT cell metabolism, viability, and cell death were affected by PET NMPs. In HaCaT keratinocytes, large PET NMPs provoked genotoxic effects. In both cell lines, PET NMPs exposure affected oxidative stress, cytokine release, and cell morphology, independently of concentration, which we could relate mechanistically to Nrf2 and autophagy activation. Collectively, we present a new PET NMP generation model suitable for studying the environmental and biological consequences of exposure to this polymer.
Assuntos
Microplásticos , Polietilenotereftalatos , Humanos , Polietilenotereftalatos/toxicidade , Polímeros , Inflamação/induzido quimicamente , Estresse Oxidativo , Autofagia , Plásticos , PolietilenoRESUMO
Micro- and nanoplastics are widespread throughout the world. In particular, polyethylene (PE) and polyethylene terephthalate or polyester (PET) are two of the most common polymers, used as plastic bags and textiles. To analyze the toxicity of these two polymers, oligomers with different numbers of units were used as models. The use of oligomers as polymeric templates has been used previously with success. We started with the monomer and continued with different oligomers until the chain length was greater than two nm. According to the results of quantum chemistry, PET is a better oxidant than PE, since it is a better electron acceptor. Additionally, PET has negatively charged oxygen atoms and can promote stronger interactions than PE with other molecules. We found that PET forms stable complexes and can dissociate the guanine-cytosine nucleobase pair. This could affect DNA replication. These preliminary theoretical results may help elucidate the potential harm of micro- and nanoplastics.
Assuntos
Microplásticos , Polietileno , Polietileno/toxicidade , Microplásticos/toxicidade , Plásticos/toxicidade , Polietilenotereftalatos/toxicidade , Polímeros , OxidantesRESUMO
The increasing presence of secondary micro/nanoplastics (MNPLs) in the environment requires knowing if they represent a real health concern. To such end, an important point is to test representative MNPLs such as the denominated true-to-life MNPLs, resulting from the degradation of plastic goods in lab conditions. In this study, we have used polyethylene terephthalate (PET) NPLs resulting from the degradation of PET water bottles. Since inhalation is an important exposure route to environmental MNPLS, we have used mouse alveolar macrophages (MH-S) as a target cell, and the study focused only on the cells that have internalized them. This type of approach is novel as it may capture the realistic adverse effects of PETNPLs only in the internalized cells, thereby mitigating any biases while assessing the risk of these MNPLs. Furthermore, the study utilized a set of biomarkers including intracellular reactive oxygen species (ROS) levels, variations on the mitochondrial membrane potential values, and the macrophage polarization to M1 (pro-inflammatory response) and M2 (anti-proinflammatory response) as possible cellular effects due to PETNPLs in only the cells that internalized PETNPLs. After exposures lasting for 3 and 24 h to a range of concentrations (0, 25, 50, and 100 µg/mL) the results indicate that no toxicity was induced despite the 100% internalization observed at the highest concentration. Significant intracellular levels of ROS were observed, mainly at exposures lasting for 24 h, in an indirect concentration-effect relationship. Interestingly, a reduction in the mitochondrial membrane potential was observed, but only at exposures lasting for 24 h, but without a clear concentration-effect relationship. Finally, PETNPL exposure shows a significant polarization from M0 to M1 and M2 subtypes. Polarization to M1 (pro-inflammatory stage) was more marked and occurred at both exposure times. Polarization to M2 (anti-inflammatory stage) was only observed after exposures lasting for 24 h. Due to the relevance of the described biomarkers, our results underscore the need for further research, to better understand the health implications associated with MNPL exposure.
Assuntos
Macrófagos Alveolares , Microplásticos , Humanos , Animais , Camundongos , Polietilenotereftalatos/toxicidade , Espécies Reativas de Oxigênio , BiomarcadoresRESUMO
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.
Assuntos
Poluentes Ambientais , Poliésteres , Poluentes Químicos da Água , Humanos , Poliestirenos/toxicidade , Poliestirenos/análise , Polietilenotereftalatos/toxicidade , Microplásticos/toxicidade , Plásticos/toxicidade , Poluentes Químicos da Água/análise , PolietilenoRESUMO
Polyethylene terephthalate (PET) is a commonly used thermoplastic in industry due to its excellent malleability and thermal stability, making it extensively employed in packaging manufacturing. Inadequate disposal of PET packaging in the environment and natural physical-chemical processes leads to the formation of smaller particles known as PET micro and nanoplastics (MNPs). The reduced dimensions enhance particle bioavailability and, subsequently, their reactivity. This study involved chemical degradation of PET using trifluoroacetic acid to assess the impact of exposure to varying concentrations of PET MNPs (0.5, 1, 5, 10, and 20 mg/L) on morphological, functional, behavioral, and biochemical parameters during the early developmental stages of zebrafish (Danio rerio). Characterization of the degraded PET revealed the generated microplastics (MPs) ranged in size from 1305 to 2032 µm, and that the generated nanoplastics (NPs) ranged from 68.06 to 955 nm. These particles were then used for animal exposure. After a six-day exposure period, our findings indicate that PET MNPs can diminish spontaneous tail coiling (STC), elevate the heart rate, accumulate on the chorion surface, and reduce interocular distance. These results suggest that PET exposure induces primary toxic effects on zebrafish embryo-larval stage of development.
Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Plásticos , Polietilenotereftalatos/toxicidade , Peixe-Zebra , Poluentes Químicos da Água/toxicidade , Nanopartículas/toxicidadeRESUMO
The replication of the hominine physiological environment was identified as an effectual strategy to develop the physiological model in vitro to perform the intuitionistic assessment of toxicity of contaminations. Herein, we proposed a dynamic interface strategy that accurately mimicked the blood flow and shear stress in human capillaries to subtly evaluate the physiological damages. To proof the concept, the dynamic air-blood barrier (ABB) model in vitro was developed by the dynamic interface strategy and was utilized to assess the toxicity of polyethylene terephthalate microplastics (PET-MPs). The developed dynamic ABB model was compared with the static ABB model developed by the conventional Transwell® system and the animal model, then the performance of the dynamic ABB model in evaluation of the PET-MPs induced pulmonary damage via replicating the hominine ABB. The experimental data revealed that the developed dynamic ABB model in vitro effectively mimicked the physiological structure and barrier functions of human ABB, in which more sophisticated physiological microenvironment enabled the distinguishment of the toxicities of PET-MPs in different sizes and different concentrations comparing with the static ABB model constructed on Transwell® systems. Furthermore, the consistent physiological and biochemical characters adopted dynamic ABB model could be achieved in a quick manner referring with that of the mouse model in the evaluation of the microplastics-induced pulmonary damage. The proposed dynamic interface strategy supplied a general approach to develop the hominine physiological environment in vitro and exhibited a potential to develop the ABB model in vitro to evaluate the hazards of inhaled airborne pollutants.
Assuntos
Técnicas Biossensoriais , Poluentes Químicos da Água , Animais , Camundongos , Humanos , Microplásticos/toxicidade , Plásticos/toxicidade , Barreira Alveolocapilar , Pulmão/química , Polietilenotereftalatos/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análiseRESUMO
Microplastics (MPs) and nanoplastics (NPs) are global pollutants with emerging concerns. Methods to predict and screen their toxicity are crucial. Elemental dyshomeostasis can be used to assess toxicity of environmental pollutants. Non-targeted metallomics, combining synchrotron radiation X-ray fluorescence (SRXRF) and machine learning, has successfully differentiated cancer patients from healthy individuals. The whole idea of this work is to screen the phytotoxicity of nano polyethylene terephthalate (nPET) and micro polyethylene terephthalate (mPET) through non-targeted metallomics with SRXRF and deep learning algorithms. Firstly, Seed germination, seedling growth, photosynthetic changes, and antioxidant activity were used to evaluate the toxicity of mPET and nPET. It was showed that nPET, at 10 mg/L, was more toxic to rice seedlings, inhibiting growth and impairing chlorophyll content, MDA content, and SOD activity compared to mPET. Then, rice seedling leaves exposed to nPET or mPET was examined with SRXRF, and the SRXRF data was differentiated with deep learning algorithms. It was showed that the one-dimensional convolutional neural network (1D-CNN) model achieved 98.99% accuracy without data preprocessing in screening mPET and nPET exposure. In all, non-targeted metallomics with SRXRF and 1D-CNN can effectively screen the exposure and phytotoxicity of nPET/mPET and potentially other emerging pollutants. Further research is needed to assess the phytotoxicity of different types of MPs/NPs using non-targeted metallomics.
Assuntos
Aprendizado Profundo , Poluentes Ambientais , Humanos , Polietilenotereftalatos/toxicidade , Microplásticos , Síncrotrons , Raios X , Plásticos , Fluorescência , Plântula , PolietilenoRESUMO
The ubiquitous pollution of plastic particles in most environmental matrices leads to concern about any potential adverse effects on human health. Most studies on the toxicological effect of nanoplastics has focused on standard particles of polystyrene. In reality humans are exposed to a large variety of different types and sizes of plastic material via oral intake and inhalation. In this study, we investigated the effect of polyethylene terephthalate (PET) nanoplastic particles from ground food containers from a supermarket. The aim was to investigate a possible link between exposure to PET nanoplastics and genotoxic response in a cell model of the human airway epithelial (A549) cells. Further, we investigated the combined effect of PET and chemicals known to alter the cellular redox state, as a model of partially compromised antioxidant defense system. DNA damage was assessed by the alkaline comet assay. The ground PET nanoplastics have a mean hydrodynamic diameter of 136 nm in water. The results showed that PET exposure led to increased reactive oxygen species production (approximately 30 % increase compared to unexposed cells). In addition, exposure to PET nanoplastic increased the level of DNA strand breaks (net increase = 0.10 lesions/106 base pair, 95 % confidence interval: 0.01, 0.18 lesions/106 base pair). Pre- or post-exposure to hydrogen peroxide or buthionine sulfoximine did not lead to a higher level of DNA damage. Overall, the study shows that exposure to PET nanoplastics increases both intracellular reactive oxygen production and DNA damage in A549 cells.
Assuntos
Microplásticos , Polietilenotereftalatos , Humanos , Microplásticos/toxicidade , Células A549 , Polietilenotereftalatos/toxicidade , Embalagem de Alimentos , Dano ao DNA , PulmãoRESUMO
Polyethylene terephthalate-based glitters (PET glitters) are a potential source of primary microplastics in the environment. However, the bioeffects of PET glitters and the associated leachates remain largely unknown. In this study, we investigated the individual and combined toxicity of five colors (silver, black, red, green, and blue) of PET glitters and their corresponding leachates on the cellular responses of Desmodesmus sp. The results indicated that the photosynthesis of Desmodesmus sp. could be partly affected by PET glitters through the shading effect, but not that of growth. Conversely, the leachates of red and green PET glitters significantly inhibited the growth of the microalga, suggesting a higher risk associated with additives leached from these colors of PET glitters. Furthermore, the adverse effects of the co-occurrence of PET glitters and leachates were closely related to oxidative stress responses in the microalgal cells, along with a color effect, which could be mainly attributed to variations in the composition and abundance of toxic additives in different colors of PET glitters. Overall, our findings provide insights into the ecological risks posed by glitters in aquatic environments and emphasize the importance of considering color factors in assessing microplastics toxicity.
Assuntos
Poluentes Ambientais , Microalgas , Poluentes Químicos da Água , Microplásticos/toxicidade , Plásticos/toxicidade , Polietileno , Polietilenotereftalatos/toxicidade , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análiseRESUMO
Plastic pollution poses a significant threat to both ecosystems and human health, as fragments of microscale size are daily inhaled and ingested. Such tiny specks are defined as microplastics (MPs), and although their presence as environmental contaminants is ubiquitous in the world, their possible effects at biological and physiological levels are still not clear. To explore the potential impacts of MP exposure, we produced and characterized polyethylene terephthalate (PET) micro-fragments, then administered them to living cells. PET is widely employed in the production of plastic bottles, and thus represents a potential source of environmental MPs. However, its potential effects on public health are hardly investigated, as the current bio-medical research on MPs mainly utilizes different models, such as polystyrene particles. This study employed cell viability assays and Western blot analysis to demonstrate cell-dependent and dose-dependent cytotoxic effects of PET MPs, as well as a significant impact on HER-2-driven signaling pathways. Our findings provide insight into the biological effects of MP exposure, particularly for a widely used but poorly investigated material such as PET.
Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Microplásticos/toxicidade , Plásticos/toxicidade , Polietilenotereftalatos/toxicidade , Ecossistema , Poliestirenos/toxicidade , Poluentes Químicos da Água/toxicidade , Monitoramento AmbientalRESUMO
BACKGROUND: The presence of polyethylene terephthalate (PET) oligomers in food contact materials (FCMs) is well-documented. Consumers are exposed through their migration into foods and beverages; however, there is no specific guidance for their safety evaluation. OBJECTIVES: This systematic evidence map (SEM) aims to identify and organize existing knowledge and associated gaps in hazard and exposure information on 34 PET oligomers to support regulatory decision-making. METHODS: The methodology for this SEM was recently registered. A systematic search in bibliographic and gray literature sources was conducted and studies evaluated for inclusion according to the Populations, Exposures, Comparators, Outcomes, and Study type (PECOS) framework. Inclusion criteria were designed to record hazard and exposure information for all 34 PET oligomers and coded into the following evidence streams: human, animal, organism (non-animal), ex vivo, in vitro, in silico, migration, hydrolysis, and absorption, distribution, metabolism, excretion/toxicokinetics/pharmacokinetics (ADME/TK/PK) studies. Relevant information was extracted from eligible studies and synthesized according to the protocol. RESULTS: Literature searches yielded 7445 unique records, of which 96 were included. Data comprised migration (560 entries), ADME/TK/PK-related (253 entries), health/bioactivity (98 entries) and very few hydrolysis studies (7 entries). Cyclic oligomers were studied more frequently than linear PET oligomers. In vitro results indicated that hydrolysis of cyclic oligomers generated a mixture of linear oligomers, but not monomers, potentially allowing their absorption in the gastrointestinal tract. Cyclic dimers, linear trimers and the respective smaller oligomers exhibit physico-chemical properties making oral absorption more likely. Information on health/bioactivity effects of oligomers was almost non-existent, except for limited data on mutagenicity. CONCLUSIONS: This SEM revealed substantial deficiencies in the available evidence on ADME/TK/PK, hydrolysis, and health/bioactivity effects of PET oligomers, currently preventing appropriate risk assessment. It is essential to develop more systematic and tiered approaches to address the identified research needs and assess the risks of PET oligomers.
Assuntos
Contaminação de Alimentos , Polietilenotereftalatos , Humanos , Contaminação de Alimentos/análise , Embalagem de Alimentos , Inocuidade dos Alimentos , Polietilenotereftalatos/toxicidade , Medição de RiscoRESUMO
Microplastics and the antibiotic sulfamethazine (SMZ) are two prevalent pollutants in regions with high human activity, particularly in coastal marine environments. In this study, the individual and joint effects of microplastics (i.e., the bio-based microplastics polylactic acid (PLA), the petroleum-based microplastics polyethylene terephthalate (PET), and the petroleum-based microplastics polystyrene (PS) at 0.5 and 5 mg/g) and sulfamethazine (SMZ, at 5 mg/g) on the gut microbiota of marine medaka (Oryzias melastigma) via dietary route were investigated. For the individual microplastics exposure, two petroleum-based microplastics PET and PS significantly decreased the alpha diversity and the complexity of co-occurrence networks of gut microbiota. Differently, the adverse effects caused by the bio-based microplastic PLA were more modest, suggesting that PLA was less hazardous than PET and PS. For the combined exposure, SMZ alone dramatically impaired the homeostasis of gut microbiota by decreasing the alpha diversity and the complexity of co-occurrence networks, while the presence of PLA or PET alleviated these adverse effects caused by SMZ. Interestingly, such an alleviation effect was not observed in the SMZ + PS groups, suggesting that different types of microplastics might exhibit distinct joint effects with SMZ. Our findings contribute to a better understanding of the ecological risk of different types of microplastics to marine ecosystems, especially in a scenario of combined pollution with antibiotics.
Assuntos
Microbioma Gastrointestinal , Oryzias , Poluentes Químicos da Água , Animais , Humanos , Microplásticos/toxicidade , Poliestirenos/toxicidade , Plásticos/toxicidade , Sulfametazina , Polietilenotereftalatos/toxicidade , Ecossistema , Poluentes Químicos da Água/toxicidade , AntibacterianosRESUMO
Domestic waste is often burned either as fuel for winter heating or in open areas, simply to get rid of waste. Polyethylene terephthalate (PET) represents an important component of plastics usage as well as of plastic waste produced. While most studies attempt to characterize environmental risk of open burning of mixed household waste, present work evaluates chemical and ecotoxicological parameters of particulate matter (PM) produced during controlled burning of PET samples. In the PM10 samples, polycyclic aromatic hydrocarbon and heavy metal concentrations were measured, ecotoxicity was evaluated using the kinetic Vibrio fischeri bioassay. Both chemical composition and ecotoxicity of the 4 samples showed significant correlation, regardless of the colored or colorless nature of the original PET sample. Antimony was found in considerable concentrations, in the range of 6.93-16.9 mg/kg. PAHs profiles of the samples were very similar, showing the dominance of 4-and 5-ring PAHs, including carcinogenic benzo(a)pyrene.
Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Material Particulado/toxicidade , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Polietilenotereftalatos/toxicidade , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , PlásticosRESUMO
The 2019 global coronavirus disease pandemic has led to an increase in the demand for polyethylene terephthalate (PET) packaging. Although PET is one of the most recycled plastics, it is likely to enter the aquatic ecosystem. To date, the chronic effects of PET microplastics (MPs) on aquatic plants have not been fully understood. Therefore, this study aimed to investigate the adverse effects of PET MP fragments derived from PET bottles on the aquatic duckweed plant Lemna minor through a multigenerational study. We conducted acute (3-day exposure) and multigenerational (10 generations from P0 to F9) tests using different-sized PET fragments (PET0-200, < 200 µm; PET200-300, 200-300 µm; and PET300-500, 300-500 µm). Different parameters, including frond number, growth rate based on the frond area, total root length, longest root length, and photosynthesis, were evaluated. The acute test revealed that photosynthesis in L. minor was negatively affected by exposure to small-sized PET fragments (PET0-200). In contrast, the results of the multigenerational test revealed that large-sized PET fragments (PET300-500) showed substantial negative effects on both the growth and photosynthetic activity of L. minor. Continuous exposure to PET MPs for 10 generations caused disturbances in chloroplast distribution and inhibition of plant photosynthetic activity and growth. The findings of this study may serve as a basis for future research on the generational effects of MPs from various PET products.