# Pilot Study of Microplastics in Snow from the Zhetysu Region (Kazakhstan)
## 3 Results and Discussion  
The Zhetysu region is characterized by a variety of natural and climatic conditions that affect the accumulation and distribution of microplastics. The snow cover height varied from several centimeters (4.0 cm) to several tens of centimeters (80.5 cm). Accordingly, the volume of snow sampled and the meltwater volume obtained from it differed markedly: the minimum meltwater volume was about 1.5 L (indicating a very thin snow layer), while the maximum reached \(\sim\)143 L (corresponding to a significantly thicker snow cover). Such differences reflect the variability of snow density and height at different locations: for example, in the mountains, dry loose snow at high altitudes may show a relatively small volume of water, whereas in the lowlands, wet snow even at lower altitudes provides a comparable water equivalent. Analysis of 53 snow samples collected at different altitudes (from about 350 m a.s.l. in the plain to about 1400-1500 m a.s.l. in the foothills) showed the presence of microplastic in most samples (92.6%). MP concentrations ranging from 1 to 12 particles per square meter, with a total number of 170 microplastic particles (Figure 2), indicated its widespread occurrence in lowland, highland, and semi-desert landscapes. The identification of microplastics in snow cover is considered as a result of the combined effect of local emissions, secondary wind transport of particles from contaminated surfaces. and long-range atmospheric transport with deposition in the form of dry and wet atmospheric deposition. The Raman spectrometry analyses of microplastic samples show differences in the location and height of the peaks, which helps to determine the composition of the materials. Each material has a unique set of peaks corresponding to specific chemical bonds in its structure. The \(X\) axis of the graphs shows the Raman shift between 0 and 3000 cm\({}^{-1}\). The \(Y\) axis represents the intensity in arbitrary units (a.u.) (Figure 3). Figure 3: Microplastic Raman spectra of selected snow samples. Figure 2: Processing of snow samples for the identification of microplastics and examples of microplastic particles found in the snow cover of the Zhetysu region, Kazakhstan. Sample No. 35 (polypropylene, PP) shows the spectral peaks in the ranges of about 810, 841, 972, 1155, 1330, 1458, and 2882 cm\({}^{-1}\), which correspond to valence and strain vibrations of C-H and C-C bonds, typical for the structure of polypropylene. The graph of sample No. 37 (polystyrene, PS, foam) shows bright peaks around 620, 1001, 1032, 1158, 1452, 1585, 1602, and 3056 cm\({}^{-1}\), among which the 1001 cm\({}^{-1}\) peak is particularly pronounced, characteristic of the ring breathing vibrations of the aromatic bonds of polystyrene. In sample No. 41 (polyethylene, PE, presumably a package), the spectrum is characterized by the presence of peaks in the region around 1062, 1128, 1295, 1439, 2848, and 2883 cm\({}^{-1}\), corresponding to the symmetric and asymmetric vibrations of the C-H bonds intrinsic to polyethylene. The Raman spectroscopy spectrum graph for sample No. 39, representing polyethylene (PE), shows typical peaks that correspond to chemical bonds in its structure. Several characteristic peaks can be identified on the spectrum of PE in the ranges of approximately 1062, 1128, 1295, 1439, 2848, and 2883 cm\({}^{-1}\). These peaks are due to symmetric and asymmetric C-H bond vibrations, which are typical for polyethylene. The peak around 1062 cm\({}^{-1}\) is typically associated with C-C vibrations in the polymer chain, and the peaks between 2848 and 2883 cm\({}^{-1}\) are related to C-H valence vibrations, which also confirms the presence of polyethylene in the sample. Polyethylene (PE), polypropylene (PP), and polystyrene (PS) are the main components of plastic waste, most frequently found in the snow cover of the Zhetysu region, often as a result of anthropogenic activities, including improper handling of packaging and household waste.