The abundance, characteristics and ecological risk assessment of microplastics in rainwater – Preliminary study

The deficit of water resources results in an increasing interest in the possibilities of using rainwater. Direct use of rainwater raises concerns due to the potential presence of micropollutants, including microplastic particles. The article presents results on the pollution of rainwater with microplastics (MPs). The samples were collected in Mala, a village and in the city of Rzeszow. The samples were collected once a month, from January to December 2023. Samples from Rzeszow were more contaminated with MPs. The mean abundance of MPs was 93.75 ± 58.67 and 213.83 ± 190.92 items/dm 3 in Mala and Rzeszow, respectively. The number of MPs detected varied depending on the season. Greater air pollution in the form of MPs was recorded in the autumn and winter months. The most frequently detected polymer was rubber. Rubber particles accounted for 79.8 % and 88.3 % of all MPs identified in Rzeszow and Mala, respectively. Ecological risk assessment was performed through the Risk Quotient and the Polymer Hazard Index, with the results indicating a potential risk that ranges from high to very high depending on the applied approach. The results obtained herein contribute new information related to MP transport and deposition in rainfall in Poland.