Ingestion of Microplastics in Edible Beach Invertebrates in Vietnam

Analyzing microplastics in marine organisms is essential for understanding the ecological and toxicological impacts of marine microplastic pollution in coastal food webs. This study investigated microplastic ingestion in three edible invertebrate species commonly found on Vietnamese sandy beaches, wedge clam Donax sp., hermit crabs Pagurus sp., and horn-eyed ghost crabs Ocypode ceratophthalmus, which differ in feeding modes and mobility, using micro-Fourier Transform Infrared spectroscopy (µ-FTIR) with a detection limit of 20 µm. Results showed that all three species ingested microplastics, with ingestion patterns varying according to species-specific traits and habitat-related feeding behaviors. The highly mobile crabs Ocypode ceratophthalmus (omnivore) and Pagurus sp. (scavenger) were found to partially reflect the polymer pollution in their ambient environment. The higher ingestion rate and diversity of polymer types observed in sedentary Donax sp. suggest that this species could serve as a potential bioindicator for microplastic pollution, given its mixed suspension and deposit feeding habits that integrate pollution from both the water column and beach sediments. Overall, these results reveal widespread microplastic ingestion among edible beach fauna, highlighting potential ecological and human health concerns, and emphasizing the need for targeted pollution management and increased public awareness. Advancing our understanding will require larger datasets and controlled experiments to more robustly assess species-specific responses and the likelihood of trophic transfer.