A Comprehensive Review of Plastics in Agricultural Soils: A Case Study of Castilla y León (Spain) Farmlands

Plastics, especially microplastics, are a diverse group of polymer-based particles, currently emerging as a global environmental threat—plastic pollution. An attempt was made to search for the presence of plastics in soils, particularly in a traditionally agricultural region such as Castilla y León (CYL). This study aimed to evaluate the use of plastics in agricultural soils in general, with an emphasis on CYL, by analyzing the present state and future perspectives on the addition of plastic waste to some agricultural soils in CYL. Surprisingly, many agricultural soils, including arable lands, irrigation, and especially greenhouse soils, receive plastic residues every day, which can lead to contaminants. By analyzing government data, we discovered that the volume of plastic waste from intensive agriculture is increasing (49,131 t in 2020) and that the current management system does not meet the needs of the sector. From this review, it can be inferred that plastics affect cultivated soils in CYL; this could affect both the economy and the soil itself and, by extension, the trophic food chain, food, and human health.