Analysis of microplastic particles in the Pilica River catchment (Poland) using FTIR imaging microscopy

Human activity increases the level of anthropogenic pollution in the river basin, including plastic particles, which may pose a serious risk to human and animal health. Wastewater treatment plants are among the key sources of microplastics (MPs) in the natural environment. The aim of the study was to analyze the occurrence and variability of MPs in treated wastewater flowing into the Pilica River, Poland. Samples were taken from selected wastewater treatment plants (raw and treated wastewater) and river control points. Fourier transform infrared (FTIR) microscopy was used to identify MPs. Plastic particles in various forms (including fibers and fragments, various sizes and colors) were found in all samples, regardless of the place of collection. In total, over 20 types of polymers were identified, of which a significant share included, among others: copolymer of ethylene and vinyl alcohol or polyvinyl chloride and others. Small MPs were characterized by the greatest diversity of polymer types. Interestingly, rubber was one of the most abundant polymer type identified. The results suggest that wastewater treatment plants can be a sink but also a source of MPs and can therefore be considered to play an important role in environmental microplastic pollution. This data may be crucial in developing strategies to limit the release of microplastics into the environment and thus achieve good status of river waters. The research was funded by the National Science Centre, Poland (Project No. 2021/43/B/ST10/01076, acronym: FARMIKRO) and the National Centre for Research and Development, Poland (Project No. HYDROSTRATEG1/000E/2022, acronym: FOSMO Water) Also see: https://micro2024.sciencesconf.org/559691/document