Microplastics Pollution in the Groundwater of Three Land Use Types, Southeastern Hungary

Groundwater is one of the sources of freshwater for drinking and agricultural activities, yet it is continuously threatened by emerging contaminants and pollutants such as microplastics (MiP). Contrary to the surface water bodies, there is a paucity of knowledge about the rate and distribution of the horizontal movement of microplastics in the groundwater of different land use areas. This study examined 18 groundwater samples collected from three land use types greenhouse, grassland, and landfill across four locations in southeastern Hungary (Szeged, Szarvas, Szentes, and Hódmezővásárhely). The research aimed to quantify microplastic contamination levels, analyze their morphological characteristics, and compare pollution levels among the land uses. After filtering 1 litre and digesting organic matter with hydrogen peroxide, microplastics were identified and counted under a microscope. The mean microplastic concentration across all samples was 7.6 ± 3.4 pieces/L, with the landfill area recording the highest level (27.50 ± 11.29 pieces/L), followed by the greenhouse (2.88 ± 0.65 pieces/L) and grassland (0.20 ± 0.20 pieces/L) areas. Statistical analysis revealed a significant difference in microplastic abundance among the three land use types, indicating that landfill areas are the primary contributors to groundwater contamination. The dominant microplastic forms were green and red fibers and fragments measuring between 1.0 and 2.1 mm. No evidence of horizontal movement of microplastics between the areas was found. The study concludes that groundwater from all land use types contains microplastics, recommending treatment before consumption or irrigation and emphasizing the need for proper plastic waste management and further research on groundwater contamination dynamics.