Sometimes, the most subtle and elusive influences may prove to be the most insidious and hazardous. In contrast to spectacular environmental disasters, such as giant oil spills or radiation accidents, the consequences of which are significant in their scale, the threat of adverse effects of plastic pollution accumulates over decades, remaining predominantly imperceptible, until it affects the fundamental underpinnings of living nature and, ultimately, our own body. Plastic pollution of the environment is duly acknowledged as one of the most significant and urgent environmental challenges of our era. The magnitude of such anthropogenic impact is indeed global. The Birmingham Plastics Network shows terrifying values: of the 10 billion tons of plastic produced, about 80% were thrown away without prior recycling, which contributed to the formation of microplastic particles polluting the environment under the exposure to external factors (sunlight, heat, humidity) [1]. These plastic fragments, smaller than 5 mm, penetrate into all components of the biosphere, which makes them dangerous. These are found in water (from the ocean depths to drinking water available on retail shelves), air, soil, and living organisms [2, 3]. Due to their small size and hydrophobic properties, they are easily incorporated into food chains at the most basic levels (for example, they are absorbed by zooplankton), and through the mechanism of biological accumulation they are transferred from one link to another, ultimately reaching the human body. There they affect the integrity of the gastrointestinal tract (GIT), and, having become part of the microbiota, induce oxidative and inflammatory responses [1, 2].

Our aim was to conduct systematic analysis of the currently available research data on the pathways for microplastics migration through food chains, assess direct and indirect effects of microplastics on physiological systems of organisms, including humans, as well as to comprehensively assess the existing and promising strategies to reduce plastic pollution and its consequences for ecosystems and public health.

The methodology for searching and selecting papers was as follows: we searched for scientific sources in international and domestic bibliographic databases PubMed, eLIBRARY.RU (RSCI), and Google Scholar. The analysis included papers published between 2015 and 2025. The search was performed using keywords and their combinations: “microplastics”, “nanoplastics”, “food chain”, “human health”, “drinking water”, “dietary exposure”, as well as equivalents in Russian (”микропластик“, ”нанопластик“, ”пищевая цепь“, ”здоровье человека“, ”питьевая вода“, ”пищевые продукты“). The initial search identified 96 papers, from which 48 sources were selected after removing duplicates and analyzing titles and abstracts. Full-text evaluation allowed us to include in the review 30 papers that met the inclusion criteria (original experimental studies and clinical trials, systematic reviews and meta-analyses focused on pathways of microplastics entry with food and water, mechanisms underlying its biological effects, and assessment of the risk for human health). Exclusion criteria were as follows: no access to the full text, irrelevance to the research topic, paper published before 2015, conference abstracts without detailed results, as well as papers containing no data in the effects of microplastics on the human body or food chains.

Main sources of microplastics entering the food chain

The mechanisms underlying plastic distribution across the environment and its subsequent entry into humans form a complex continuous chain of transformation and migration.

The process begins with the most obvious secondary source – the dumping of large plastic items (such as drinking water bottles) into the ocean or onto land. At this stage a direct adverse effect of plastic is reported: ingestion of human waste by marine mammals, reptiles, birds, and fish can lead to their death or the development of life-threatening diseases, such as exhaustion, rupture of internal organs, and suffocation of coral reef inhabitants due to lack of oxygen and sunlight [4]. In turn, turtles, birds, and mammals are at risk of drowning when caught in nets and traps, as well as when interacting with polymeric materials.

The following should be noted: there is evidence that floating plastics can carry chemicals and pathogenic bacteria to coastal areas, which can be a factor of the subtle but significant impact on human health [5].

Then, under the exposure to ultraviolet radiation from sunlight, the plastic becomes brittle, and mechanical action of waves and sand abrasion lead to its gradual fragmentation into many microscopic particles that can directly enter the human body through the digestive organs (for example, in case of accidental swallowing of water while swimming or when drinking unpurified water due to the inability to use another source of hydration), respiratory organs, and skin in case of direct contact [6].

However, at the same time there is one more, a less noticeable but no less powerful channel for pollutant entry: household activities. The hazard is the routine procedure, i.e. synthetic apparel laundering. Every wash releases hundreds of thousands of microscopic fibers into wastewater that treatment plants are unable to fully capture, which results in contamination of the apparently purified water [7]. This also includes wear and tear on car tires, particles of which are washed away by rain into water bodies, and urban dust, which carries microplastics through the air.

Once in the ocean or soil, particles and fibers become part of an ecological cycle. In aquatic ecosystems, these are swallowed by zooplankton representing the basis of the marine food chain; particles and fibers settle to the bottom and are absorbed by filter feeding organisms, such as mussels and oysters [3, 7]. On land, microplastics are deposited on agricultural land and taken up by soil invertebrates and plant root systems. Bioaccumulation results in buildup of pollutant concentrations in the organisms’ tissues, and biomagnifications results in the concentration increase with the transition from one trophic level to another. Thus, a predatory fish that feeds on smaller species, or a herbivore that eats contaminated plants accumulates large amounts of plastic.

The final link in this chain is human, who by eating seafood, fish, agricultural products, and even breathing city air, inevitably becomes the final target of such pollution, closing the cycle that began with the bottle we, humans, threw away or the next time we washed a fleece sweater.

In addition to the above mechanisms underlying danger to humans from microplastic particles, there is another one. It is associated with using items that have become firmly established in our everyday life ― plastic bottles. Scientists have proven that microplastic particles are often (in 93% of cases) found in bottled water [8]. The major contamination canals are both the packaging material itself (both the container and the lid) and the production process. Bottles made of polyethylene terephthalate (PET) undergo mechanical degradation and release microparticles during use (repeated opening and closing, compression and, most importantly, thermal exposure during storage). Considerable amounts of particles also enter the water from polypropylene lids.

Furthermore, particles yielded by decomposition of plastic are found even in familiar foods such as table salt, honey, wine, tea, coffee capsules, beer, and carbonated beverages [9−11]. The research show that the sea salt, produced by evaporating ocean water, is a particularly significant source: it can contain hundreds of microparticles per kilogram of product, directly linking ocean pollution to the food we eat [9]. The analysis of honey from different world’s regions also revealed microplastic fibers and fragments, likely entering the honey through atmospheric transport and deposition on flowers or during collection and processing by beekeepers [10]. Microscopic plastic particles penetrate into various beverages through multiple points of contact with polymeric materials [11]. When poured into plastic containers, these migrate from the bottle walls, necks, and lids. Wine may contain particles from plastic corks, and hot drinks such as coffee and tea may contain particles from plastic filters, tea bags, coffee capsules, or disposable tableware. Even the process of preparing hot drinks can wash away microparticles, for example, when boiling water in a plastic electric kettle. Microplastics can also be accidentally ingested from non-food sources during oral hygiene and tooth brushing, such as toothpaste, toothbrushes, orthodontic implants, and denture materials [11]. These examples clearly demonstrate that microplastics are already circulating in a vicious circle, becoming part of the key components of our diet. This makes microplastic consumption virtually inevitable.

Thus, plastic pollution represents a closed cycle of migration and transformation: what started as full-size plastic waste, causing direct death to animals, is transformed through fragmentation processes and the household release of microparticles into an invisible but large-scale threat. It is significant that even bottled water, food products, and personal hygiene items become a source of microplastics entering the body, closing the anthropogenic pollution cycle. This systemic problem requires a comprehensive solution at all stages: from production to disposal of plastic materials.

Potential risk for human health

Microplastics invasion of human body represents a multi-layered threat, realized through several interconnected mechanisms. The main receipt pathways are GIT (with food and water), respiratory system, and to a lesser extent, skin. According to the available data, the effects of microplastics on the respiratory, gastrointestinal, cardiovascular and nervous systems are best understood. However, the impact on other body’s systems, including endocrine and reproductive systems, has not been studied sufficiently. The currently available information is fragmentary, it makes it possible to only hypothesize about potential mechanisms of action and long-term consequences. Particularly challenging is the assessment of the cumulative effect in chronic low-dose exposure, typical for real-world conditions. Thus, despite growing body of scientific evidence, many aspects of the impact of microplastics on the human body require further systematic study.

Digestive system

By studying the information on the routes of plastic penetration into the human body, it can be concluded that the most likely route is oral. When consumed in this way, microplastics have a multi-component effect on the GIT. Microplastic particles can cause mechanical damage to enterocytes. Small particles sized 0.1–150 µm can translocate across the mucosal barrier and accumulate in intestinal epithelial cells, causing the tight junction integrity disruption and increased permeability of the intestinal wall playing a role of the barrier between the intestinal lumen and body’s bloodstream [12]. Such intestinal barrier alteration leads to translocation of bacteria, which can cause immune responses and intestinal inflammation. Inflammatory processes can only worsen due to disturbances in lipid and energy metabolism [13]. Furthermore, disturbances in energy metabolism and immune responses are confirmed by gut microbiota alterations: the studies report alteration of the gut microbiota microbial composition often leading to reduction of the number of friendly bacteria, such as Lactobacillus and Bifidobacterium, contributing to growth of opportunistic microorganisms and thereby causing dysbiosis [2, 13, 14]. Of particular danger is the synergistic effect of sorption of pathogenic microorganisms and toxins on the surface of microplastics, which increases their bioavailability and pathogenic potential.

Respiratory system

As stated above, textiles, the fibers of which enter the atmosphere every time a synthetic item is washed, represents one of the sources of microplastics in the atmosphere. Inhalation of microplastics is characterized by selective deposition of particles depending on their size [15]. Particles with a diameter of 2.5−10 µm are deposited mainly in the upper respiratory tract, while ultrafine fractions (< 2.5 µm) reach the alveoli. Pulmonary macrophages show limited phagocytic activity for particles larger than 10 µm, which leads to persistence of those and the development of chronic granulomatous inflammation. Experimental data suggest the dose-dependent reduction of lung capacity and increase in the airway resistance associated with chronic inhalation of polypropylene fibers. Fibrous changes in the interalveolar septa and neoplastic transformation associated with constant proliferation against the background of chronic inflammation are considered to be the long-term consequences.

Nervous system

In addition to microplastic particles, there are also smaller substances, the nanoplastic particles (< 100 nm) demonstrating the ability to penetrate the blood-brain barrier through adsorption-mediated transport [16, 17]. In the experiment involving mice, intravenous administration of fluorescence labeled polystyrene particles with a diameter of 20 nm resulted in their accumulation in the hippocampus and cerebral cortex 24 h after injection. Neurological impairment manifests itself in the form of dose-dependent cognitive decline, short-term memory impairment, and motor activity alteration. New data suggest that the exposure to pollutants in the environment disrupts the connection between the gut and the brain, leading to abnormalities in brain immunity, structure, neural connections, and behavior [17, 18]. Neurotoxicity mechanisms include mitochondrial dysfunction, microglial activation, and impaired synaptic plasticity. Electrophysiological tests record the long-term potentiation changes in hippocampal neurons when the particle concentration ≥ 1 mg/L.

Circulatory system

The cardiovascular system appears to be one of the most vulnerable targets for microplastics circulating in the bloodstream. Numerous scientific papers focused on the issue of the plastic environmental pollution adverse effects on human metabolism contain the reports of the direct relationship between the presence of microplastic particles and the development of endothelial dysfunction, as well as pro-thrombotic states [19]. The mechanisms underlying such effects are multifaceted: in vitro studies show that polyethylene particles with a diameter of 1 μm at a concentration of 50 μg/mL induce apoptosis of human umbilical vein endothelial cells through caspase-3 activation [20]. This process underlies the vascular lining injury, which has been confirmed by animal experiments, in which the accelerated formation of atherosclerotic plaques in the aorta under the combined exposure to microplastics and the atherogenic diet was reported. And there are also hemostatic disorders manifested by platelet activation, increased fibrinogen levels, and shorter blood clotting time [21]. Cardiotoxic effects, including cardiac arrhythmia and reduced left ventricular ejection fraction, become the clinically significant effects of such multi-layered abnormality, which increases the risk of myocardial infarction and heart failure in the long term.

In the context of the global spread of microplastics, the hygienic strategies aimed at minimizing its entry into the human body through the main routes of exposure are particularly relevant. These strategies are based on the principle of multi-level protection, covering both individual practices and the improvement of water treatment and food quality control systems.

As for drinking water supply, advanced water purification methods are of primary importance. Today, there are no special regulatory documents for controlling water filtration from the pollutant described above, i.e. microplastics, in the Russian Federation [22]. However, the current standard water purification methods make it possible to reduce microplastics concentration in the purified water. Thus, according to the research, combined use of sand filtration and membrane technologies (in particular, nanofiltration membranes with the pore size 0.001 µm) allows to increase the microplastic removal efficiency to 99.9% [23]. At home, one can use activated carbon and reverse osmosis water purification systems, which have proven their effectiveness in removing particles larger than 0.0001 µm [24].

Significant potential for reducing exposure is associated with optimizing dietary habits and choosing sustainable foods. Epidemiological studies suggest significant differences in microplastic levels between the aquaculture-raised and wild-caught seafood [25]. As for eating seafood, limiting the consumption of filter-feeding mollusks (mussels, oysters), which demonstrate the greatest ability to accumulate microparticles, seems to be the best solution. When choosing table salt, which has been found to contain large amounts of microplastic particles, preference should be given to rock salt, the microplastic content of which is 2−-3 orders of magnitude lower than in sea salt [9].

As for household hygiene, the issue of synthetic textiles deserves special attention. It has been found that the use of microfiber filters during washing can reduce the release of plastic fibers into wastewater by 80% [26]. Switching to the use of clothing made from natural materials, as well as the use of special detergents that reduce mechanical damage to fibers represent one more protective measure.

The correct choice of packaging and storage conditions for products is an important aspect of food hygiene. Avoiding heating food in plastic packaging is a science-based recommendation, since it has been found that the exposure to temperature of 60−70 °C increases microparticle migration 5−7-fold [27]. Priority should be given to glass and ceramic containers, especially for long-term storage and heat treatment of products.

As for respiratory hygiene, the use of class FFP2 respirators, capable of retaining up to 94% of particles sized 0.3−1 µm, under the conditions of high dust content represents an effective protective measure [28]. It is recommended to use air purifiers with HEPA filters demonstrating 99.97% efficiency for particles larger than 0.3 µm to reduce microplastics concentration in indoor air of residential buildings.

Improving the regulatory framework occupies a special place in hygienic prevention. It is necessary to revise hygienic standards and determine maximum permissible concentrations of microplastics in drinking water and food products. The development of monitoring systems enabling regular monitoring of microparticle content in key environmental objects is a promising area [29].

Thus, the current hygienic strategies to reduce negative effects of microplastics represent a complex of complementary measures based on the principles of evidence-based medicine and aimed at disrupting the pathways, through which microparticles enter the human body with water, food and air.

CONCLUSION

The analysis conducted has shown that the issue of microplastic pollution represents a global challenge characterized by the closed cycle of migration and transformation of plastic materials. A continuous chain of interconnected processes can be traced: from the initial pollution of the environment with macroplastics to the micro- and nanoparticles entering the human body. Of particular concern is the ability of microplastics to enter food chains and undergo bioaccumulation, reaching maximum concentrations at higher levels of the food chain, including humans.

Numerous studies have shown that microplastics have significant pathogenic potential, which is realized through a complex of mechanisms: from mechanical damage to cellular structures to the induction of oxidative stress, chronic inflammation, and dysfunction of major physiological systems. The effects on the gastrointestinal tract, respiratory, and cardiovascular systems is best studied while the effects on the endocrine and reproductive functions requires further research.

The existing strategies to reduce adverse effects of microplastics considered in the paper include both technological solutions (membrane filtration, sorption purification, coagulation) and hygienic practices aimed at breaking the pathways, through which microplastics enter the body. Of particular importance is the development of the regulatory framework and monitoring systems enabling objective assessment of microplastic content in environmental objects and food products.

Prospects for overcoming the challenge are associated with realization of the comprehensive approach that involves improving plastic waste recycling technologies, developing water and air purification methods, and fostering an environmentally friendly consumer culture. No less important is the development of scientific research focused on in-depth study of the long-term effects of microplastic exposure and the development of effective detoxification methods.

Thus, the issue of microplastic pollution requires the combined efforts of the scientific community, authorities, manufacturers and consumers to develop and implement effective measures to reduce the negative impact on ecosystems and human health. Only a comprehensive, interdisciplinary approach will help break the vicious circle of anthropogenic plastic pollution and minimize its consequences for present and future generations.