The key facts

  • Samples were taken in 2021–2023 at 23 stations: Tomsk, Novosibirsk, Omsk, Tyumen and Kemerovo regions, KhMAO, YaNAO and Altai Krai
  • More than 90% of particles were fibers 0.3–1 mm in size; the share of PET in 2022–2023 samples exceeded 40%
  • The chemical hazard index of polymers rose from 96.2 in 2021 to 991 in 2023, remaining at the lower boundary of the hazardous level under the applied methodology

Scale of the Study

The study, published in the journal Pollutants, covered the territory from the Altai foothills to the Arctic Circle. Snow samples were collected during the period of maximum snow accumulation in 2021–2023 at 23 observation stations. Observations were conducted in the Tomsk, Novosibirsk, Omsk, Tyumen and Kemerovo regions, the Khanty-Mansi and Yamalo-Nenets Autonomous Okrugs, as well as in Altai Krai.

Growth in Content and Particle Composition

Although microplastics were distributed unevenly across the regions, scientists recorded an increase in its average amount over the years of observations and assessed this as a trend of accumulation in the snow cover. More than 90% of the particles found were fibers; the share of small fragments reached 8%, while films and spherical particles together accounted for no more than 2%. Particles measuring 300–1000 micrometers (0.3–1 mm) predominated. In the 2022–2023 samples, the share of polyethylene terephthalate (PET) exceeded 40%; polypropylene, polyethylene and polystyrene were also noted — materials used in the production of synthetic fabrics, clothing, bags, bottles and containers. According to the authors, the abundance of fibers and their composition indicate that one of the main sources of pollution may be synthetic textiles.

Links with Population Density and Precipitation

No direct relationship was found between the amount of microplastics and population density, gross regional product, or proximity to roads. At the same time, a moderate dependence on snow cover thickness was detected: as precipitation increased, the deposition of particles from the atmosphere onto the snow intensified.

Assessment of Ecological Risk

The chemical hazard index of polymers rose from 96.2 in 2021 to 991 in 2023. According to the authors, this corresponds to the lower boundary of the hazardous level in the applied assessment methodology. The increase is explained by the appearance in the samples of polyacrylonitrile and polyurethane with high hazard scores. The potential ecological risk index, which takes concentrations into account, increased from 1.92 to 19.7 but remained in the lowest risk category. Study participant Alexey Rednikin explained that although polymers with a high chemical hazard index are encountered, their concentration is still relatively low; however, the growth of the indicators points to the need to continue observations.