Ingestion of Microplastic by Fish of Different Feeding Habits in Urbanized and Non-urbanized Streams in Southern Brazil

Most studies that address microplastic (MP) ingestion by fish are conducted in marine environments; however, freshwater ecosystems such as rivers and streams are also important sources of these particles in coastal areas. Considering that increasing urbanization surrounding watersheds increases the sources of plastic pollution and that fish feeding behavior may influence the probability of ingestion of these particles, the aim of this study was to evaluate the ingestion of MP by fish of different feeding habits in urbanized and non-urbanized streams. The fish were captured in ten streams in Southern Brazil and the stomach contents of 294 individuals belonging to 13 species were analyzed. Individuals of ten species ingested MP of fiber type. From a generalized linear mixed model, we observed that the urbanized streams and the omnivorous habit showed a positive correlation with MP intake. Our results suggest that both types of streams present MP, but this pollutant is probably more prominent in heavily urbanized sites, which may represent important sources of MP for larger systems along the river basin. This evidences the importance of preserving riparian areas of small order streams as a means to reduce MP inputs into these ecosystems.