(Uploaded by Plazi for the Bat Literature Project) This study shows the abundance of contamination by microplastics (MPs) and the first record of contamination by MPs in bats. Additionally, we tried to understand the mechanism of the environmental contamination of bats. Therefore, the digestive and respiratory tracts from 81 adult bats belonging to 25 species were extracted for analysis. Bats were captured in different locations in the Brazilian Amazon (Altamira, Bragança, Brasil Novo, Medicilândia, Nova Timboteua, Placas, São Félix do Xingu, Uruará and Vitória do Xingu, all in the state of Pará). The results showed that all species were contaminated with MPs in at least one of the analyzed systems. For the digestive system, the form of contamination occurs through bioaccumulation and biomagnification by the ingestion of contaminated food or water. In the case of the respiratory system, contamination occurs through the inhalation of MPs suspended in the atmospheric air. The different foraging characteristics of bats, the type of capture strategy for this food, and the type of habitat reinforce the idea that plastic contaminants are present in all environments.