Microplastic ingestion by fish from beaches with different characteristics in a tropical bay

This study aimed to identify and quantify microplastic ingestion by fish species in four sites in Todos os Santos Bay (TSB), two beaches with estuarine characteristics and two beaches exposed to the open sea. The gastrointestinal contents of 1,339 individuals (19 species) were analyzed, and 20.01% of the specimens were contaminated. Four trophic guilds were defined: generalists, zooplanktivores, zoobenthivores, and piscivores. Microplastics were present in all trophic guilds, with higher ingestion in piscivorous species. Ingestion occurred in all species, regardless of specimen size, weight, location, or time of year. Our results highlight that microplastic contamination in TSB is widespread, even in less populated areas and species of different trophic guilds. This increases the need for complementary studies to determine the specific composition of microplastics, potential sources of contamination, as well as to determine mitigation measures directed at microplastic pollution in coastal ecosystems.