It is snowing microplastics in Western Siberia.

Area of Science:

• Environmental Science
• Atmospheric Chemistry
• Polymer Science

Background:

• The atmosphere acts as a significant pathway for the dispersal of anthropogenic particles, including microplastics (MPs) and synthetic fibers.
• Snowpack analysis offers a valuable method for monitoring the presence and atmospheric transport of these microplastic pollutants and man-made textile fibers.

Purpose of the Study:

• To investigate the abundance and characteristics of microplastics (MPs) and man-made textile fibers in snow across a wide area of Western Siberia.
• To determine the deposition rates and mass loading of these particles in the snowpack.
• To explore potential sources and transport pathways of detected particles using atmospheric modeling.

Main Methods:

• Sampling and analysis of microplastics (MPs) and man-made textile fibers in deposited snow across Western Siberia, from the Altai Mountains to the Arctic Circle.
• Quantification of particle abundance (items m⁻²) and mass loading (mg m⁻² and mg L⁻¹).
• Utilizing the FLEXPART Lagrangian dispersion model to simulate potential particle source regions and transport patterns.

Main Results:

• Rayon fibers constituted 44% of detected particles, with the remaining 56% being microplastics (MPs) including PET, PA, PC, and PP.
• The highest recorded particle concentration was 2817 ± 915 items m⁻², with a daily deposition rate of 25.8 items m⁻² d⁻¹.
• Maximum mass particle load reached 4444 ± 1530 mg m⁻², or 34.9 ± 12 mg L⁻¹ in melted snow. Concentrations were higher in southern regions but did not correlate with population density.
• Atmospheric modeling indicated that particles can be transported via both short-range and long-range atmospheric transport, with potential for cross-border movement.

Conclusions:

• The study confirms widespread contamination of snow in Western Siberia by microplastics (MPs) and synthetic fibers, primarily originating from atmospheric deposition.
• Both local and long-distance atmospheric transport mechanisms contribute to particle distribution, underscoring the transboundary nature of microplastic pollution.
• Further research is needed to fully elucidate the sources and impacts of these atmospheric pollutants on remote ecosystems.