Evaluation of microplastic pollution in the Vilnelė River

The aim of the work was to carry out experimental research and numerical simulation of microplastic pollution in the Vilnelė River. Six locations were selected for the experimental studies: 3 measurement points and 3 releasers. It was determined that the average concentration of microplastics at the selected measurement points was in the range between 0.10 and 0.42 particles/L. The concentration of microplastics at the selected releasers ranged from 3 to 31.6 particles/L. A morphological analysis of the microplastics was also carried out. Synthetic polymer microplastics were found to be the dominant type among all detected microplastics. The ANSYS software was used for numerical modelling. The Euler–Lagrange method was selected to model the movement of microplastics in river water. It was found that microplastic pollution in the Vilnelė River was mainly lower than in other selected rivers and lakes around the world. The numerical simulation of microplastic pollution in the Vilnelė River provided models that, by depicting the pollution sources, show how far microplastic particles are transported within one hour. These models help identify the most suitable locations for further microplastic research, enable the prediction of pollution levels, and allows other researchers to repeat the research.