## 3 Results and Discussion
### Microscopic Analysis
#### 3.1.2 SEM-EDS Analysis  
Figures 5 and 6 illustrate the morphology of the fractionated sediment samples and products of extraction with organic solvents. The samples under consideration display irregular geometry and shape, with their dimensions correlating with the implemented fractionation procedure. The powders within a fraction of less than 25 \(\upmu\)m exhibit a flake-like morphology, while particles exceeding 25 \(\upmu\)m demonstrate angular characteristics. Particles of smaller size also present an acidular morphology. It is noteworthy that the particles within the fraction of less than 25 \(\upmu\)m encompass a range of sizes, including very small particles (less than 10 \(\upmu\)m) and larger particles (greater than 10 \(\upmu\)m). In contrast, larger fractions are characterized by particles of more uniform sizes and consistent shapes. Predominantly, these particles display a combination of rounded and angular shapes. Additionally, EDS was performed, and the results are compiled in Table 4. Depending on the samples' origin, they display diverse chemical compositions.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Sample Name**} & \multicolumn{10}{c}{**Element Symbol** \(\dagger\)** **Atomic Concentration [\%]**} \\ \hline BAT sediment & O & 57.05 & Ca & 12.49 & C & 21.09 & N & 9.37 & & & & & & \\ \hline BAT sediment & O & 59.77 & Si & 10.00 & Al & 10.04 & Na & 8.51 & C & 11.35 & & & & \\ \hline SZY sediment & O & 57.17 & Si & 14.06 & C & 17.41 & Al & 5.47 & Na & 5.69 & Te & 0.16 & & & \\ \hline SZY sediment & O & 57.36 & C & 29.75 & Ca & 8.21 & Na & 1.85 & Cl & 1.04 & Si & 1.19 & Al & 0.51 & \\ \hline BIS sediment & O & 65.97 & Si & 12.39 & Fe & 5.12 & Al & 9.88 & Mg & 4.20 & K & 1.77 & & & \\ \hline CZT2 sediment & O & 65.84 & Si & 12.69 & Al & 8.84 & C & 12.63 & & & & & & \\ \hline UMU sediment & O & 60.98 & Si & 9.67 & Al & 8.95 & Fe & 3.13 & C & 13.86 & Na & 1.39 & Te & 0.24 & Cl & 0.52 \\ \hline DCM extracts * & C & 100 & & & & & & & & & & & \\ \hline \hline \end{tabular}  
* In EDS observations it was noticed that all samples of DCM extracts contained only carbon.  
\end{table}
Table 4: Elemental composition of selected materials obtained by EDS analysis.  
Figure 4: Microscopic images of sediment samples of fractions below 25 \(\upmu\)m and particles separated using a magnet.  
Figure 5: SEM images of all isolated sediment fractions obtained from BIS DCM.  
Samples collected from roadside sand contained a higher concentration of mineral components, such as calcium, aluminum, sodium, and metals like iron, likely originating from the wear and tear of brake pads. Furthermore, tellurium was detected in these samples. The sources and confirmation of its presence in the surface layer of soil at the sampling site have been extensively described in the work by [PERSON] et al. [40].  
EDS analysis of materials obtained from melted snow did not reveal the presence of calcium, which is consistent with the information provided in the section discussing thermogravimetric analysis (Section 3.3).  
SEM images of organic-solvent-extracted and concentrated rubber particles are depicted in Figure 6. These particles exhibit a spherical shape and tend to agglomerate, leading to the formation of larger clusters with sizes smaller than 2 \(\upmu\)m. The precise sizes of these particles were further examined using the DLS technique, which is described below.  
The EDS analysis of all samples (Figure 6A-F) revealed only the presence of carbon. This further confirms that the organic fractions extracted contain rubber particles originating from car tires.  
Figure 6: SEM images taken for extracts after washing with organic solvents: (**A**) UMU, (**B**) BIS, (**C**) BAT, (**D**) SZY, (**E**) CZT1, (**F**) DK11.