Airborne microplastics are emerging pollutants originating from disposable tableware, packaging materials, textiles, and other consumer goods. Microplastics vary in shape and size and exposed to external factors break down into even smaller fractions. Airborne microplastics are abundant in both urban and natural environments, including water bodies and glaciers, as particles can travel long distances. The potential toxicity of airborne microplastics cannot be underestimated. Microparticles, especially those < 10 µm, entering the human body through inhalation or ingestion have been shown to cause serious adverse health effects, such as chronic inflammation, oxidation stress, physical damage to tissues, etc. Microplastics adsorb toxic chemicals and biopolymers, forming a polymer corona on their surface, affecting their overall toxicity. In addition, microplastics can also affect carbon dynamics in ecosystems and have a serious impact on biochemical cycles. The approaches to improve sampling techniques and develop standardized methods to assess airborne microplastics are still far from being perfect. The mechanisms of microplastic intracellular and tissue transport are still not clear, and the impact of airborne microplastics on human health is not understood well. Reduced consumption followed by collection, reuse, and recycling of microplastics can contribute to solving the microplastic problem. Combinations of different filtration techniques and membrane bioreactors can be used to optimize the removal of microplastic contaminants from wastewater. In this review we critically summarize the existing body of literature on airborne microplastics, including their distribution, identification, and safety assessment.

The objective of the study was a pre-screening of the microplastic (MP) content in surface water and benthic sediments of Kara Darya and Chirchiq rivers, the first-order tributaries of the Syr Darya River (Uzbekistan). For the first time, surface water and benthic sediment samples were taken from this region, and quantitative screening of MPs 0.15–5.00 mm in size was performed. A combined visual and μRaman-based methodology was used to quantify and characterize artificial polymer microparticles from the surface water and bottom sediments of two rivers. The average abundance of MPs in the Kara Darya River and Chirchiq River waters was found to be 4.28 ± 0.09 and 0.95 ± 0.36 items per m³, and that in benthic sediments attained 244 ± 28.9 and 333 ± 11.5 items per kg of dry soil, respectively. MP concentration in surface water and benthic sediments of the Kara Darya River significantly exceeded (p-value < 0.01) that in the Chirchiq River. Microfibers were most abundant; the proportion of MP fibers in the water of the Kara Darya and Chirchiq rivers amounted to 89 and 95%, respectively, and that in benthic sediments of the rivers was 86 and 84%, respectively. The dominance of microfibers may indicate the route of entry to the rivers through domestic wastewater treatment plant discharges. The polymer microparticles in the surface water and benthic sediments of the Kara Darya and Chirchiq rivers were mainly represented by polyethylenterephtalate (PET), which accounted for half of all MPs detected in the Kara Darya River. Microparticles of textile origin were particularly abundant in the Kara Darya River, where viscose and nylon fibers were also found, which suggests the leading role of synthetic textiles in the pollution. The reported data are the first experimental evidence of MP pollution of the Syr Darya tributaries, but the distribution and circulation of MPs in surface water in Central Asia requires further comprehensive studies.

Microplastics (MPs) in aquatic environments can be associated with various substances, including persistent organic pollutants, which add to the problem of plastic ecotoxicity. The abundance of 1–5 mm microplastics and concentrations of particle-adsorbed organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in sandy sediments from three beaches in recreational areas along the upper Ob River in Western Siberia were assessed. MP pollution levels in the Ob River beach sands ranged from 24 ± 20.7 to 104 ± 46.2 items m⁻² or, in terms of mass concentration, from 0.26 ± 0.21 to 1.22 ± 0.39 mg m⁻². The average abundance of MP particles reached 0.67 ± 0.58 items kg⁻¹ or 8.22 ± 6.13 μg kg⁻¹ in the studied sediments. MP concentrations were significantly higher in number (p < 0.05) and mass (p < 0.01) at the riverbank site downstream of the Novosibirsk wastewater treatment plant (WWTP) outfall compared to these at the upstream and more distant beaches. Most MPs (70–100%) were represented by irregularly shaped fragments. The polymer composition of MPs varied between sites, with a general predominance of polyethylene (PE). The study revealed associations of MPs with PCBs and OCPs not previously detected in the riverbed and beach sediments, suggesting that these substances are circulating in the Ob River basin. Although MP concentrations were higher downstream of the WWTP, the maximum levels of particle-associated OCPs were observed in the beach sands of the site farthest from the urban agglomeration. The pesticides γ-HCH, 4,4-DDT, and 4,4-DDE were detected on MPs at relatively low concentrations. PCBs were more abundant in the studied samples, including 118 dioxin-like congener. The results obtained indicate that the Ob River is susceptible to plastic and persistent organic pollutant (POP) contamination and serve as a starting point for further studies and practical solutions to the problem.

This article shows the impact of the COVID-19 pandemic on the environment of the Katunsky reserve on the eco-trail “To the Land of Lakes and Waterfalls”. The research was carried out by three methods: assessment of trail degradation, camps and phytomass in damaged and reference areas. During the pandemic, a process of severe ecosystem degradation was identified, associated with a dramatic increase in the number of visitors to the reserve. Closed state borders and lifted restrictions on entry and exit to the Altai Republic have made the Katunsky Nature Reserve popular for recreational activities.

Atmospheric microplastic pollution is an emerging environmental concern, yet data on ecological risks posed by snow cover pollution remain sparse. This study presents the first assessment of ecological risks associated with snow cover pollution in Western Siberia. Pollution and risk levels were quantified using the pollution load index (PLI), the polymer hazard index (PHI), and the potential ecological risk index (PERI). Microplastics were detected in all snow samples; however, the pollution level was rated as ‘low’ across all sampling sites throughout the observation period. Although median PHI values for the snow cover indicated medium hazard, the presence of samples referred to the hazard categories ‘danger’ and ‘extreme danger’ (up to 27% in 2023) pointed to localized pollution by potentially toxic polymers. In contrast, the average PERI values remained low (1.92–19.7), as this index accounts for both polymer toxicity and microplastic abundance. However, the index showed a consistent upward trend over the three-year observation period, driven by the increase in both the proportion of hazardous polymers and the total microplastic load. Thus, although the quantitative content of microplastics in the snow cover of Western Siberia was low, the high PHI values at some sampling sites and the occurrence of polymers containing toxic monomers like polyacrylonitrile (PAN) and polyurethane (PU) indicate a potential ecological risk that requires further monitoring.