Ingestion and Toxicity of Polystyrene Microplastics in Freshwater Bivalves

Abstract

The ubiquity of microplastics in aquatic ecosystems has raised concerns over their interaction with biota. However, microplastics research on freshwater species, especially mollusks, is still scarce. We, therefore, investigated the factors affecting microplastics ingestion in the freshwater mussel Dreissena polymorpha. Using polystyrene spheres (5, 10, 45, 90 µm), we determined the body burden of microplastics in the mussels in relation to 1) exposure and depuration time, 2) body size, 3) food abundance, and 4) microplastic concentrations. D. polymorpha rapidly ingested microplastics and excreted most particles within 12 h. A few microplastics were retained for up to 1 wk. Smaller individuals had a higher relative body burden of microplastics than larger individuals. The uptake of microplastics was concentration-dependent, whereas an additional food supply (algae) reduced it. We also compared the ingestion of microplastics by D. polymorpha with 2 other freshwater species (Anodonta anatina, Sinanodonta woodiana), highlighting that absolute and relative uptake depends on the species and the size of the mussels. In addition, we determined toxicity of polystyrene fragments (≤63 µm, 6.4-100 000 p mL -1 ) and diatomite (natural particle, 100 000 p mL -1 ) in D. polymorpha after 1, 3, 7, and 42 d of exposure, investigating clearance rate, energy reserves, and oxidative stress. Despite ingesting large quantities, exposure to polystyrene fragments only affected the clearance rate of D. polymorpha. Further, results of the microplastic and diatomite exposure did not differ significantly. Therefore, D. polymorpha is unaffected by or can compensate for polystyrene fragment toxicity even at concentrations above current environmental levels.

Effects of microplastics mixed with natural particles onDaphnia magnapopulations

“…Diatomite has been used as natural reference material in previous microplastics studies. In the freshwater mollusks Dreissena polymorpha and Lymnea stagnalis, diatomite was in general not more toxic than polystyrene microplastics (Weber, Jeckel, et al 2021;Weber, von Randow, et al 2021) but induced a stronger effect on the antioxidant capacity in the former species (Weber, Jeckel, and Wagner 2020) at identical numerical concentrations. In Chironomus riparius larvae, diatomite was toxic but less so than polyvinyl chloride microplastics at identical mass-based concentrations (Scherer et al 2019).…”

Effects of Different Polystyrene Concentrations on the Bioaccumulation of As, Cd, and Pb in Ruditapes Philippinarum

“…Therefore, ingestion of MPs allocates a pathway for the metal transfer to organisms (Naqash et al 2020). However, this is species dependent; as in the experimental exposure to MPs in mussels, it was found that mussels can excrete most microplastic particles within a certain period of time, and that the burden of MPs in large mussels is much less than that in small mussels (Weber et al 2021).…”

Diel Pattern of Microplastic Residues in Zebrafish

“…1,2 The potential toxicity and health effects of MPs have attracted significant research attention. 3,4 The toxicokinetic behavior of pollutants is important for understanding their occurrence and toxicity development in organisms. 5,6 Therefore, the toxicokinetics of MPs and how they may bioaccumulate within organisms have become a critical scientific and practical issue due to the potential health effects of MPs.…”