Trends and gaps in microplastics research in Tropical freshwater ecosystems
Aquatic environment, bibliometric review, plastic pollution, Tropical ecosystems
Although microplastic contamination is a very recent topic, knowledge increased rapidly, especially in the last decade. Despite this, freshwater ecosystems have received less attention than marine ones, particularly in the tropics. Our review aims to present the state of research on microplastic contamination in Tropical freshwater ecosystems. We compared studies across different countries, ecosystems, and types of samples, emphasizing the knowledge advances and existing gaps. We found a total of 190 studies. Research began less than 10 years ago and has increased significantly since 2019. Almost half of the studies were concentrated in Brazil and India. Rivers were the most studied environments, followed by lakes. The contamination was studied in water, sediments, and biota. Although research and study complexity have increased over the years, Tropical freshwater ecosystems remain understudied. We emphasized the need for more studies in African countries and Tropical Australia, as well as in reservoirs across all Tropical regions. It is also crucial to evaluate contamination related to flooding dynamics, in addition to aquatic invertebrates. Advancements in research on this topic are essential to provide a clear picture of the real problem in the tropics, enabling better mitigation and conservation actions in the future.