Nano- and Microplastics Migration from Plastic Food Packaging into Dairy Products: Impact on Nutrient Digestion, Absorption, and Metabolism

Study of fibrous microplastic and natural microfiber levels in branded milk samples from Italy

As far as we know, there is no evidence regarding the microfiber (MF) occurrence and abundance in branded milk samples from Italy. Therefore, a total of 20 milk samples from 5 brands were collected and analyzed using a digestion step with hydrogen peroxide followed by filtration. Natural and synthetic MFs were classified according to the evaluation of surface morphology (i.e., shape and texture), followed by chemical identification using Fourier transform infrared spectroscopy (FTIR) microspectroscopy. Results revealed the occurrence of MFs in 67.5% of the analyzed samples and showed variability ranging between 1-27 particles/100 mL with an overall average of 3.85 MFs/100 mL. The FTIR analyses confirmed the presence of polyethylene, polyester, acrylic, and cellulosic MFs. According to the literature, the contamination of milk may occur at various stages along the production chain. The blood-milk barrier would prevent MFs from being transferred across the mammary gland into the milk. The highest MF levels found in ultra-high temperature skimmed milk of some brands may indicate the more complex the processing of milk, the more MFs they contain. However, due to the different MF types and polymers, an unambiguous conclusion on MF sources cannot be made. MFs could be shed from the filters used in the milk processing factories and the protective clothing for workers. Therefore, the MF contamination should be properly investigated along the entire supply chain, identifying the sources of contamination and implementing control strategies and mitigation measures.

Identification and occurrence of microplastics in drinking water bottles and milk packaging consumed by humans daily

Microplastic (MP) pollution has become a growing concern due to its potential environmental and health impacts. The present study aimed to investigate the presence of MPs in specific brands of drinking water bottle and milk packets. To identify the MPs, researchers employed microscopic techniques, FTIR spectroscopy, and FESEM with EDS. The types of polymers were determined by comparing the obtained values with reference standards. The study also assessed the potential daily microplastic exposure from drinking water and milk consumption. MPs were detected in the samples in three different shapes: filaments, fibers, and fragments. Four types of polymers were identified: polypropylene (PP), polyamide (PA), polysulfone (PSU), and polyethersulfone (PES). The colors observed included violet, blue, green, red, and black. In the analyzed drinking water samples, a total of 13 MPs sized 1-3 mm and 7 MPs sized 3-6 mm were found. In the milk samples, there were 2 MPs sized 4-5 mm and 4 MPs sized 2-3 mm. The results of the study indicate that MPs are present in the examined drinking water and milk, which are directly consumed by humans. This suggests that microplastic pollution may occur during the manufacturing or packaging processes of these products. The study recommends implementing measures to reduce microplastic contamination at the beginning of the production process for drinking water and milk.

Analysis of Brazilian plastic waste management in the global context and case study of the City of Vitória, Espírito Santo

This review analyses Brazil's current stage of plastic waste management, comparing it to what is being carried out worldwide. The Brazilian National Solid Waste Policy established principles and guidelines for solid waste management. However, a decade after its implementation, the results demonstrate timid results about those expected. Brazil's official solid waste and plastics recycling rates are around 4% and 1%, respectively, considerably behind countries with comparable economic growth levels. This work dedicates considerable attention to microplastic pollution, a worldwide concern with potential effects on water bodies, the atmosphere, soils, human health, and vegetal and animal lives. A case study on the solid waste management system in Vitória City, the capital of Espírito Santo, was developed. Besides, a portrait of the pollution in Vitória and Espírito Santo Bays in the atmosphere and mangrove areas is presented. The more critical issues found were the low adherence of the population's city in the selective waste collection (what is reflected in the low solid waste recycling rates), plastic debris, and tiny plastic in the waters, coexisting with heavy metals and hydrocarbons-originated from industrial and anthropogenic activities; microplastics are present in the atmosphere, adding their adverse effects to those of the pollutants already existing in the air and the illegal disposal of waste and the anthropogenic activities which degrade the mangrove ecosystems. A global treaty is being discussed at the United Nations. It's expected that their definitions, initially promised by the end of 2024, will be able to eradicate plastic pollution effectivelly.

Environmental toxicology of microplastic particles on fish: A review

The increase in plastic debris and its environmental impact has been a major concern for scientists. Physical destruction, chemical reactions, and microbial activity can degrade plastic waste into particles smaller than 5 mm, known as microplastics (MPs). MPs may eventually enter aquatic ecosystems through surface runoff. The accumulation of MPs in aquatic environments poses a potential threat to finfish, shellfish, and the ecological balance. This study investigated the effect of MP exposure on freshwater and marine fish. MPs could cause significant harm to fish, including physical damage, death, inflammation, oxidative stress, disruption of cell signalling and cellular biochemical processes, immune system suppression, genetic damage, and reduction in fish growth and reproduction rates. The activation of the detoxification system of fish exposed to MPs may be associated with the toxicity of MPs and chemical additives to plastic polymers. Furthermore, MPs can enhance the bioavailability of other xenobiotics, allowing these harmful substances to more easily enter and accumulate in fish. Accumulation of MPs and associated chemicals in fish can have adverse effects on the fish and humans who consume them, with these toxic substances magnifying as they move up the food chain. Changes in migration and reproduction patterns and disruptions in predator-prey relationships in fish exposed to MPs can significantly affect ecological dynamics. These interconnected changes can lead to cascading effects throughout aquatic ecosystems. Thus, implementing solutions like reducing plastic production, enhancing recycling efforts, using biodegradable materials, and improving waste management is essential to minimize plastic waste and its environmental impact.

Antibacterial and antioxidant plant-derived aldehydes: A new role as cross-linking agents in biopolymer-based food packaging films

In recent years, biopolymer-based food packaging films have emerged as promising alternatives to petroleum-based plastic food packaging films. Various additives have been explored to enhance their properties, and one such group of additives is natural plant aldehydes. These aldehydes are commonly employed to improve the antibacterial and antioxidant properties of biopolymer-based food packaging films. However, their potential role as cross-linking agents is often overlooked in these applications. This work introduces the properties of commonly used natural plant aldehydes in biopolymer-based food packaging films. Specifically, it summarizes the effects of natural plant aldehydes such as cinnamaldehyde, vanillin, and others on the properties of biopolymer-based food packaging films. Furthermore, the application of biopolymer-based food packaging films functionalized with natural plant aldehydes in food preservation is discussed. This work concludes that various natural plant aldehydes serve as effective antimicrobial agents and antioxidants. They can not only physically interact with biopolymers but also undergo chemical cross-linking reactions with some polymers through Schiff base reactions and Michael addition reactions, thereby further improving the comprehensive properties of the film.

Micro- and nano-plastics, intestinal inflammation, and inflammatory bowel disease: A review of the literature

Plastics, encompassing a wide range of polymeric materials, and their downstream products (micro- and nanoplastics, MNPs) are accumulating in the environment at an alarming rate, and they are linked to adverse human health outcomes. Considering that ingestion is a main source of MNPs exposure, the impact of plastics is particularly relevant towards intestinal inflammation and inflammatory bowel disease (IBD). However, the study of MNPs has been limited by obstacles relating to sample collection, preparation, and microplastics analysis based on optical microscopy and chemical analysis, which we detail in this review alongside potential solutions. We summarize available data on human exposure to MNPs and overall health outcomes, with particular focus on data pertaining to intestinal inflammation, microbiome perturbations, and related outcomes. We include ecologic perspectives, and human, in vitro, and animal model studies. We discuss the way forward in MNPs and IBD research, including knowledge gaps and future research.

Phytolacca americana extract as a quality-enhancing factor for biodegradable double-layered films based on furcellaran and gelatin - Property assessment

For the first time, novel active double-layered films based on furcellaran (FUR) and gelatin (GEL) with the addition of Phytolacca americana (PA) extract were obtained. The 1st layer consisted of FUR and GEL, while the aqueous extract of P. americana berries was added in three different concentrations to the 2nd FUR-based layer. The films were characterised by good mechanical (TS range of 0.0011-0.0013 MPa, EAB range between 30.38 %-33.51 %) and water properties (WVTR range of 574.74-588.49 g/m2xd). Structural analysis (SEM and AFM) confirmed good film structure: regular, without cracks or air bubbles. The films showed antioxidant activity tested via the Folin-Ciocâlteu method (4.77-20.70 mg GAExg-1), FRAP assay (0.18-3.40 mM TExg-1) and CUPRAC assay (48.63-53.99 mM TExg-1). The film with the highest PA concentration (6 %) demonstrated the ability to neutralise free radicals, DPPH• and ABTS2+•, at the levels of 1.97 % and 17.34 %, respectively. The ecotoxicity test performed on Lepidium sativum seeds confirmed the lack of ecotoxic film aspects. The biodegradation test indicated that the films are biodegradable. The obtained films can be a good alternative to plastic packaging films (used in the food packaging industry), which are currently a global problem related to the development of post-consumer plastics.

Teabag-derived micro/nanoplastics (true-to-life MNPLs) as a surrogate for real-life exposure scenarios

The potential health implications of environmental micro/nanoplastics (MNPLs) are increasingly concerning. Beyond environmental exposure, other sources such as food packaging, including herbal/teabags, may also be significant. This study investigates the release of MNPLs from three commercially available teabags. By simulating tea preparation, MNPL samples were extracted and characterized using a range of analytical techniques: scanning electron microscopy (SEM), transmission electron microscopy (TEM), attenuated total reflectance/Fourier transform infrared spectroscopy (ATR-FTIR), dynamic light scattering (DLS), laser Doppler velocimetry (LDV), and nanoparticle tracking analysis (NTA). The results confirmed that the teabags were made of nylon-6 (NY6), polypropylene (PP), and cellulose (CL) and that microfibers and nano-range particles (NPLs) were present in the leachates. NTA data revealed that the number of released NPLs was 1.20 × 109/mL (PP; 136.7 nm), 1.35 × 108/mL (CL; 244 nm), and 8.18 × 106/mL (NY6; 138.4). The leachate particles were then stained with iDye Poly-Pink and used to expose three human intestine-derived cell types (Caco-2, HT29, and HT29-MTX) to assess their biointeractions and the role of the mucosubstances in vitro. The results demonstrated that after 24 h of exposure to 100 μg/mL NPLs, there was significant uptake of PP-NPLs in HT29-MTX cells, as a model of cells segregating high amount of mucus. A similar uptake was observed for CL-NPLs in HT29 and HT29-MTX cells, while NY6-NPLs were internalized preferentially in Caco-2 cells. These findings underscore the importance of identifying new environmentally relevant MNPL exposure sources, for developing realistic MNPLs samples, and further investigating their potential human health effects.

Quantification of polystyrene microplastics in water, milk, and coffee using thermogravimetry coupled with Fourier transform infrared spectroscopy (TGA-FTIR)

Rapid quantification of plastic contaminants, particularly microplastics (MPs), in foods is a challenge. This study introduces a novel method using Fourier transform infrared spectroscopy coupled with thermogravimetric (TGA-FTIR) and chemometric analysis for the quantification of MPs in foods. A model study was performed using polystyrene (PS) MPs (1 μm) added to various foods, namely, water, milk, and coffee without any pretreatment. Foods were spiked with PS microbeads at different concentrations, heated in a TGA, and FTIR spectra of the gases evolved from the TGA were collected over time. The FTIR spectral data were used to construct a Gram-Schmidt profile and identify the characteristic PS peak. The spectrum corresponding to the peak maxima was extracted to represent the specific PS concentration. A dataset of selected spectra and their associated PS concentrations was preprocessed prior to calibration and cross-validation using PLS regression models, for each food matrix studied. The results showed that the PLS models reliably predicted the PS content in water, milk, and coffee with R2CV above 0.96, and RMSECV between 0.045 and 0.07 mg. Multivariate detection limit intervals (LODmin/LODmax) were 0.041/0.085 mg for water, 0.061/0.128 mg for milk and 0.06/0.101 mg for coffee. This method is simple to operate, relatively rapid, and most importantly, does not require sample pretreatment. This research also suggests that the analysis is applicable to a broad range of food samples, and it is suitable for quantifying MPs and nanoplastics regardless of size and shape. The chemometric approach also shows its potential for automation in daily detection and quantification of MPs in food safety control.

Micro-Nanoparticle Characterization: Establishing Underpinnings for Proper Identification and Nanotechnology-Enabled Remediation

Microplastics (MPLs) and nanoplastics (NPLs) are smaller particles derived from larger plastic material, polymerization, or refuse. In context to environmental health, they are separated into the industrially-created "primary" category or the degradation derivative "secondary" category where the particles exhibit different physiochemical characteristics that attenuate their toxicities. However, some particle types are more well documented in terms of their fate in the environment and potential toxicological effects (secondary) versus their industrial fabrication and chemical characterization (primary). Fourier Transform Infrared Spectroscopy (FTIR/µ-FTIR), Raman/µ-Raman, Proton Nuclear Magnetic Resonance (H-NMR), Curie Point-Gas Chromatography-Mass Spectrometry (CP-gc-MS), Induced Coupled Plasma-Mass Spectrometry (ICP-MS), Nanoparticle Tracking Analysis (NTA), Field Flow Fractionation-Multiple Angle Light Scattering (FFF-MALS), Differential Scanning Calorimetry (DSC), Thermogravimetry (TGA), Differential Mobility Particle [Sizing] (DMPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Scanning Transmission X-ray Microspectroscopy (STXM) are reviewed as part of a suite of characterization methods for physiochemical ascertainment and distinguishment. In addition, Optical-Photothermal Infrared Microspectroscopy (O-PTIR), Z-Stack Confocal Microscopy, Mueller Matrix Polarimetry, and Digital Holography (DH) are touched upon as a suite of cutting-edge modes of characterization. Organizations, like the water treatment or waste management industry, and those in groups that bring awareness to this issue, which are in direct contact with the hydrosphere, can utilize these techniques in order to sense and remediate this plastic polymer pollution. The primary goal of this review paper is to highlight the extent of plastic pollution in the environment as well as introduce its effect on the biodiversity of the planet while underscoring current characterization techniques in this field of research. The secondary goal involves illustrating current and theoretical avenues in which future research needs to address and optimize MPL/NPL remediation, utilizing nanotechnology, before this sleeping giant of a problem awakens.

Degradation of Polymer Materials in the Environment and Its Impact on the Health of Experimental Animals: A Review

The extensive use of polymeric materials has resulted in significant environmental pollution, prompting the need for a deeper understanding of their degradation processes and impacts. This review provides a comprehensive analysis of the degradation of polymeric materials in the environment and their impact on the health of experimental animals. It identifies common polymers, delineates their degradation pathways, and describes the resulting products under different environmental conditions. The review covers physical, chemical, and biological degradation mechanisms, highlighting the complex interplay of factors influencing these processes. Furthermore, it examines the health implications of degradation products, using experimental animals as proxies for assessing potential risks to human health. By synthesizing current research, the review focuses on studies related to small organisms (primarily rodents and invertebrates, supplemented by fish and mollusks) to explore the effects of polymer materials on living organisms and underscores the urgency of developing and implementing effective polymer waste management strategies. These strategies are crucial for mitigating the adverse environmental and health impacts of polymer degradation, thus promoting a more sustainable interaction between human activities and the natural environment.

Polystyrene nanoplastics induced learning and memory impairments in mice by damaging the glymphatic system

The excessive usage of nanoplastics (NPs) has posed a serious threat to the ecological environment and human health, which can enter the brain and then result in neurotoxicity. However, research on the neurotoxic effects of NPs based on different exposure routes and modifications of functional groups is lacking. In this study, the neurotoxicity induced by NPs was studied using polystyrene nanoplastics (PS-NPs) of different modifications (PS, PS-COOH, and PS-NH2). It was found that PS-NH2 through intranasal administration (INA) exposure route exhibited the greatest accumulation in the mice brain after exposure for 7 days. After the mice were exposed to PS-NH2 by INA means for 28 days, the exploratory ability and spatial learning ability were obviously damaged in a dose-dependent manner. Further analysis indicated that these damages induced by PS-NH2 were closely related to the decreased ability of glymphatic system to clear β-amyloid (Aβ) and phosphorylated Tau (P-Tau) proteins, which was ascribed to the loss of aquaporin-4 (AQP4) polarization in the astrocytic endfeet. Moreover, the loss of AQP4 polarization might be regulated by the NF-κB pathway. Our current study establishes the connection between the neurotoxicity induced by PS-NPs and the glymphatic system dysfunction for the first time, which will contribute to future research on the neurotoxicity of NPs.

Designing healthier and more sustainable ultraprocessed foods

The food industry has been extremely successful in creating a broad range of delicious, affordable, convenient, and safe food and beverage products. However, many of these products are considered to be ultraprocessed foods (UPFs) that contain ingredients and are processed in a manner that may cause adverse health effects. This review article introduces the concept of UPFs and briefly discusses food products that fall into this category, including beverages, baked goods, snacks, confectionary, prepared meals, dressings, sauces, spreads, and processed meat and meat analogs. It then discusses correlations between consumption levels of UPFs and diet-related chronic diseases, such as obesity and diabetes. The different reasons for the proposed ability of UPFs to increase the risk of these chronic diseases are then critically assessed, including displacement of whole foods, high energy densities, missing phytochemicals, contamination with packaging chemicals, hyperpalatability, harmful additives, rapid ingestion and digestion, and toxic reaction products. Then, potential strategies to overcome the current problems with UPFs are presented, including reducing energy density, balancing nutritional profile, fortification, increasing satiety response, modulating mastication and digestion, reengineering food structure, and precision processing. The central argument is that it may be possible to reformulate and reengineer many UPFs to improve their healthiness and sustainability, although this still needs to be proved using rigorous scientific studies.