Abstract: The ongoing use of plastic polymers to manufacture food packaging has raised concerns about the presence of nano- and microplastics (NMPs) in a variety of foods. This review provides the most recent data on NMPs' migration from plastic packaging into milk and dairy products. Also discussed are the possible effects of NMPs on nutrient digestion, absorption, and metabolism. Different kinds of milk products, including skimmed or whole liquid and powder milk, infant formula milk, and other dairy products, have been found to contain NMPs of various sizes, shapes, and concentrations. NMPs may interact with proteins, carbohydrates, and fats and have a detrimental impact on how well these nutrients are digested and absorbed by the body. The presence of NMPs in the gastrointestinal tract may impact how lipids, proteins, glucose, iron, and energy are metabolised, increasing the risk of developing health conditions such as diabetes, cardiovascular disease, hypertension, and some cancers. In addition to NMP, plastic oligomers released from food packaging material have been found to migrate to various food simulants and milk, though their effect on human health has yet to be investigated. Viewpoints on potential directions for future studies on NMPs and nutrient digestion, absorption, and health are also presented in this review.

Microplastics (MPs) are small pieces of plastics. They are ubiquitous in the environment and can enter the freshwater environment from surface run-off and wastewater effluent (treated and untreated), industrial effluent, degraded plastic waste, and atmospheric deposition. They are not usually destroyed but convert into one phase to another. They are a source of air pollution, occurring in dust and airborne fibrous particles. Mostly MPs are non-biodegradable while some MPs are biodegradable, which can be decomposed in the presence of ultraviolet (UV) light or by the action of microorganisms. Popular methods: chemical, spectroscopic, and thermo-analytical are available for the determination of the chemical composition and size of plastic particles. This chapter discusses the uses, health hazards, sources, and transport of MPs particles.

Our understanding of the fate and distribution of micro- and nano- plastics in the marine environment and their impact on the biota compartment is limited by the intrinsic difficulties of conventional analytical techniques (light scattering, FT-IR, Raman, optical and electron microscopies) in the detection, quantification and chemical identification of small particles in liquid samples. Here we propose the use of optical tweezers, a technique awarded in 2018 with the Nobel prize, as an analytical tool for the study of micro- and nano- plastics in sea water. In particular, we exploit the combination of optical tweezers with Raman spectroscopy (Raman Tweezers, RTs) to optically trap plastic particles with sizes from tens of µm down to 90 nm and unambiguously reveal their chemical composition. RTs applications are shown on particles made of the most common plastic pollutants, including polyethylene, polypropylene, nylon and polystyrene, that are artificially fragmented and aged directly in seawater. RTs allow us to assess the size and shapes of microparticles (beads, fragments, fibers) and can be applied to investigate particles covered with organic layers. Furthermore, operating at the single particle level, RTs enable unambiguous distinction of plastic particles from marine microorganisms and seawater minerals, overcoming the capacities of standard Raman spectroscopy in liquid, limited to average measurements. Coupled to suitable extraction and concentration protocols, RTs could have a strong impact in the study of the fate of micro and nanoplastics in marine environment, as well as in the understanding of the fragmentation processes on a multi-scale level.

Manufactured nanoplastic particles (NPs) are indispensable for in vitro and in vivo testing and health risk assessment of this emerging environmental contaminant. High surface area and inherent hydrophobicity of plastic material, makes production of NPs devoid of any contaminants very challenging. In this study we produced nanoprecipitated polyethylene terephthalate (PET) NPs (300 nm hydrodynamic diameter) and characterized presence of ionic surfactant sodium dodecyl sulfate (SDS) by 1H NMR. Relative ratio of NP/surfactant was monitored on the basis of chemical shifts characteristic for PET and SDS. For a wide range of surfactant/NP ratio (1:17 to 1:1.2), measured zeta potential changed from -42.10 to -34.93 mV, but no clear differences were observed in cellular assays performed in protein-rich media on primary human cells. The remaining impurities contributed to the outcome of biological assays applied in protein-free buffers, such as human red blood cells hemolysis. As size, shape, zeta potential and contaminants of NPs may all be relevant parameters for biological effects of NPs, relative quantification of impurities exemplified in our work by application of 1H NMR for PET NPs and ionic surfactant SDS could be a valuable auxiliary method in quality control of manufactured NPs.

Given the broad and intense use of plastic, society is being increasingly affected by its degradation and by-products, particularly by microplastics (MPs) -fragments smaller than 5 mm in size-, and nanoplastics (NPs) -with sizes less than 1 µm. MPs and NPs may enter the body primarily through inhalation, consumption, and skin contact. Once ingested, MPs can penetrate tissues, deviating to other parts of the body, and hence potentially affecting important cellular pathways such as nonconforming chemokine receptors that control the communication between the fetus and the mother. Consequently, the potential health harm induced by MP internalization is a major issue, evidenced by multiple studies demonstrating harmful consequences in diverse animal models and human cells. Here, an overview of the various modes of exposure to MPs and NPs is presented, including inhalation, placental transfer, ingestion, breastmilk consumption, and skin absorption, as well as placental and fetal toxicity due to plastic particles based on animal and in vitro studies. Though MPs in our environment are becoming more recognized, their developmental toxicity is still scarcely known. Besides negatively affecting pregnancy, MPs and NPs have been shown to potentially harm the developing fetus, given their ability to cross the placental barrier. Still, considerable gaps remain in our understanding of the dispersion and toxicity of these particles in the environment, as well as the precise types of NPs and MPs bearing the greatest dangers. As a result, we advocate for larger-scale epidemiological investigations, the development of novel approaches for measuring NP and MP exposures, and the necessity of understanding the toxicity of various kinds of NPs to guide future research efforts.

Micro-nano-plastics (MNPs) are an important constituent of atmospheric aerosol. However, there is still no standard procedure for their sampling and size fractionation, which is an obstacle to the aggregation and critical analysis of results obtained by different research groups. This review focuses on the sampling and fractionation methodologies used for MNPs. Moreover, a straightforward optimized methodology for the sampling and fractionation is proposed.

The present review critically examines the advancements in the past 5 years concerning the re-search on the bioavailability of the nanoplastics (NPLs) to freshwater plankton. With a specific emphasis on two bioavailability components: uptake availability and toxico-availability, we dis-cuss the recent progress in the understanding of the adsorption, absorption, trophic transfer and biological effects in phyto- and zooplankton induced by NPLs exposure. The influence of the plankton on the NPLs bioavailability via excretion of the biomolecules and formation of eco-corona is also examined. In spite of the important research developments, there are still con-siderable knowledge gaps with respect to NPLs biouptake and trophic transfer by plankton, as well as a potential adverse effect in natural aquatic systems. As plankton play a critical role in primary production, nutrient cycling and food web structure, understanding the interaction be-tween NPLs and plankton is essential in assessing the potential implications of the nanoplastics pollution for aquatic ecosystem biodiversity and services.

Microplastics (MPs) and nanoplastics (NPs) are distributed and transferred among the four major environmental compartments (air, water, soil, and biota) and have been already found in humans, making crucial to develop remediation technologies to tackle this kind pollution. Photocatalysis can be used to eliminate MPs present in contaminated wastewater effluents before their discharge into waterbodies. In this work, several green TiO2-based semiconductors were prepared using the extrapallial fluid (EPF) of Mytilus edulis sea water mussels as doping precursor. The semiconductors were then used as films or powders to photocatalytically degrade polystyrene (PS) NPs and MPs and polyethylene (PE) MPs. It was found that the obtention of green TiO2-based semiconductors with good characteristics for photocatalytic purposes (anatase crystalline phase, presence of porosity, activity in visible light and high surface area) seems not enough to achieve high degradation efficiency. The operational conditions of the reaction system should be also taken into account. For instance, the convenience of using semiconductors in the form of films can be overcome by their limited exposed surface area or the null adsorption of the semiconductor in the MPs particles. Additionally, crystallinity of the semiconductor can be a more determinant factor to take into account when performing photocatalysis of MPs.

Static (SLS) and dynamic (DLS) light scattering techniques are assessed for their capacity to detect colloidal particles with diameters between d = 0.1 and 0.8 µm at very low concentrations in seawater. The detection limit of the apparatus was determined using model monodisperse spherical polystyrene latex particles with diameters 0.2 µm and 0.5 µm. It is shown that the concentration and size of colloids can be determined down to about 10^-6 g/L. Seawater obtained from different locations in western Europe was characterized using light scattering. It was found that seawater filtered through 0.45 µm pore size membrane filters was within the experimental error the same as that of ultrapure Milli-Q water containing the same amount of sea salt and no colloids could be detected with DLS. When the seawater was filtered through 0.8 µm pore size filters, colloidal particles were detected. The measurements show that the concentration of colloids in the seawater samples is not higher than 10^-6 g/L and that they have an average diameter of about 0.6 µm. We stress that these particles are not necessarily nanoplastics.

Contamination of the environment with nano- and microplastic particles exerts a threatened impact on the aquatic ecosystems and sustainable catfish aquaculture. The presence of nanoplastics has been found to have a detrimental impact on both aquatic and terrestrial ecosystems. The present study examines the effect of polystyrene nanoplastics on DNA, erythrocytes, oxidative status and renal of catfish in addition to the potential protective effects of Chlorella vulgaris bioremeditation and selenium to hinder this effect. Six equal groups of fish were used as follows: Group 1: served as a control group and received water free from PS NPs; Group 2: was exposed to PS NPs at a concentration of 5mg/L; Group 3: was exposed to PS NPs (5mg/L) + selenium (1mg/kg diet); Group 4: was exposed to PS NPs (5mg/L) + C. vulgaris (25g/kg diet); Group 5: was supplemented with C. vulgaris (25g/kg diet); and Group 6: was supplemented with selenium (1mg/kg diet). The results indicated that PS NPs induced oxidative stress by significantly elevating MDA activities and slightly reducing antioxidant biomarkers, resulting in DNA damage, increased frequency of micronuclei, erythrocyte alterations, and numerous histopathological alterations in kidney tissue. Selenium and C. vulgaris significantly ameliorated the oxidative/antioxidant status, reduced DNA damage, micronucleus frequency, erythrocyte alterations, and morphology of kidney tissue. Nevertheless, further research is needed to evaluate in detail the mechanism behind the toxicity with nano-microplatics in aquatic system.

Microplastics and nanoplastics (MP/NPs) have been found everywhere they have been searched. On the top of Everest, in the Mariana Trench, on the clouds e recently, microplastics have been discovered in the human placenta, meconium and babies’ feces. In this review we explain what the consequences of the presence of these pollutants in fetuses and newborns are, with particular attention to human breastfeeding. Finally, we outline the possible political and social solutions to the problem of plastic overproduction that characterizes the modern world.

: Microplastics and nanoplastics (MNPs) are becoming an increasingly severe global problem due to their widespread distribution and complex impact on living organisms. Apart from their environmental impact, the effects of MNPs on living organisms have also continued to attract attention. The harmful impact of MNPs has been extensively documented in marine invertebrates and larger marine vertebrates like fish. However, the research on the toxicity of these particles on mammals is still limited, and their possible effects on humans are poorly understood. Considering that MNPs are commonly found in food or food packaging, humans are primarily exposed to them through ingestion. It would be valuable to investigate the potential harmful effects of these particles on gut health. This review focuses on recent research exploring the toxicological impacts of micro- and nanoplastics on the gut, as observed in human cell lines and mammalian models. Available data from various studies indicate that the accumulation of MNPs in mammalian models and human cells may result in adverse consequences, in terms of epithelial toxicity, immune toxicity, and disruption of gut microbiota. The paper also discusses the current research limitations and prospects in this field, aiming to provide a scientific basis and reference for further studies on the toxic mechanisms of micro- and nanoplastics.

Background. Escalating global plastic production, expected to reach 34,000 million tons by 2050, poses a significant threat to human and environmental well-being, particularly in aquatic ecosystems. Microplastics (MP) and nanoplastics (NP), which originate from the degradation of plastics, are of concern due to their potential bioaccumulation and uptake of pollutants. This study addresses identification methods and focuses on insect meal, a raw material for aquaculture feed. Methods. By using different techniques, the study was able to detect MP and NP in insect meal samples. Chemical digestion with KOH at 60°C efficiently removed organic matter without affecting the synthetic polymer polyethylene (PE). Filtration, confocal Raman microscopy, SEM and TEM were used for comprehensive analysis and integrity tests on PE films were performed using Raman and FTIR spectroscopy. The results showed the presence of PE microplastic particles in the insect meal, which was confirmed by correlative Raman and SEM mapping on a positively charged surface. In addition, the increased resolution of the Raman microscope identified submicrometric PE NP (800 nm). Transmission electron microscopy (TEM) with energy dispersive X-ray spectroscopy (EDX) confirmed plastic-like structures in the insect meal, highlighting the presence of PE plastics characterized by irregular shapes and some agglomeration. The higher carbon concentration in the EDX analysis supported the plastic nature, which was also confirmed by Raman spectroscopy. Conclusions. The study provides a robust method for the detection of MP and NP in insect meal and provides valuable insight into the possible presence of plastics in insect-based aquafeeds. The combination of different analytical methods increases the reliability of the results and sets the stage for future investigations that could focus on the quantification of NP and the assessment of their potential environmental impact.