Characterization of microplastic contamination and influencing factors in different environmental compartments of a coal mining subsidence area in northern Anhui, China

Environmental pollution caused by microplastics (MPs) has garnered significant global attention, however, research on MPs contamination of various environmental compartments within mining regions remains limited. The objective of this study was to investigate the occurrence and distribution of MPs in soil, surface water, and sediment, as well as the factors influencing the distribution of microplastics in the Panji Mining Area in Huainan City, Anhui Province, China. The findings indicate that MPs contamination in soil and surface water within the study area is substantial. The average abundance of MPs in soil, surface water, and sediment were 1860.8 n·kg, 11,323.7 n·m, and 384.0 n·kg, respectively. The dominant MPs were transparent, fibrous particles <0.1 mm, with polyethylene (PE) common in soil and polypropylene (PP) prevalent in surface water and sediment. A significant correlation was observed among MPs and environmental factors such as pH, total phosphorus (TP), and total organic carbon (TOC) (p < 0.05) showed a positive correlation in soil while in sediment, MPs abundance showed a positive correlation with pH and TOC (p < 0.05). Additionally, a positive correlation was observed of MPs abundance with pH, total nitrogen (TN), and nitrate nitrogen (NO₃-N) (p < 0.05) in surface water. This study provides insights into the characteristics, distribution, and environmental risks of MPs in mining areas, laying a foundation for the development of prevention and control strategies to mitigate MPs pollution in these regions.