Glitter ingestion by bromeliad-dwelling macroinvertebrates: implications for freshwater microplastic contamination

Microplastics (MPs) are pervasive pollutants due to their extensive dispersion across terrestrial, marine, freshwater environments, and even the atmosphere. Beyond the common sources of MPs from the degradation of larger plastic items, an often-overlooked primary source is glitter. Widely incorporated into everyday products, glitter not only poses a significant environmental risk due to its ease of dispersion but also holds cultural importance in regions like Brazil, where it is extensively used in festivities. Understanding glitter as a type of MP can offer valuable insights into the effects of MPs on aquatic ecosystems, particularly concerning freshwater macroinvertebrates. Given the ecological significance of this issue, our study investigated the ingestion and potential bioaccumulation of MPs by macroinvertebrates in the phytotelmata of Aechmea blanchetiana bromeliads. Organisms were exposed to a MP treatment (0.1 g/L glitter) for seven days, followed by taxonomic identification and analysis of MP distribution across body segments. Statistical tests assessed variations in MP distribution among taxa and body regions. Results revealed significant MP ingestion, with the highest concentrations in Culicidae and Chironomidae, suggesting that their generalist feeding behaviors facilitate MP intake. Observations also pointed to preferential accumulation of MPs in certain body parts, indicating potential bioaccumulation. Additionally, the presence of fragmenting MP particles within these taxa highlights their potential role in enhancing MP bioavailability in aquatic environments. Chironomidae and Culicidae, through ingestion and fragmentation, may increase MP dispersal across trophic levels, which could exacerbate bioaccumulation risks within the food web. This evidence supports the use of Chironomidae and Culicidae as effective biomonitors for MPs and calls attention to the ecological implications of glitter pollution in tropical freshwater ecosystems.