0
Article Tier 2 Sign in to save

Are Daphnia similis Playing a Significant Role in Microplastic Biofragmentation?

Water Air & Soil Pollution 2023 12 citations

AI summary Read the abstract

Researchers exposing the freshwater microcrustacean Daphnia similis to polystyrene microspheres found that the organisms reduced particle size by nearly 33% over six days through biofragmentation, demonstrating that zooplankton ingestion is an underappreciated pathway for breaking down microplastics into smaller particles.

Polymers
Models

Environmental plastic contamination is a global problem, which is driven by the growing demand for plastics. Over time, plastics undergo fragmentation processes and become so-called microplastics, which have been shown to be a threat to the various environments where their presence occurs. The most accepted hypothesis is that, like macroplastics, microplastics have fragmented into smaller and smaller particles, with sub-micrometer sizes. However, little is known about fragmentation rates and which are the most determining factors in this process. The main objective of the present study was to investigate the biofragmentation capacity of microplastics by Daphnia similis, a microcrustacean from inland waters. The organisms were exposed to polystyrene spheres (PS; 24 µm), under two concentrations: 135 and 1350 items/50 mL, for a period of 6 days. The rate of biofragmentation was obtained by analyzing the size of the particles over time (48, 96, and 144 h); ingestion and survival rates were also investigated. At the end of the exposure, the microspheres had their size reduced by 32.8%. From the first 48 h, the organisms ingested particles, and the rate of ingestion was dose dependent. Mortality was shown to increase in the treatment of higher concentration. The results demonstrate the ability of this microcrustacean to induce the reduction of the dimensions of microplastics, evidencing a fragmentation pathway previously neglected.

More Papers Like This

Article Tier 2

Chronic and Acute Water-Soluble Microplastics Uptake and Effects on Growth and Reproduction of Daphnia magna

AI summary Read the abstract

Researchers found that two water-soluble microplastics — polyvinyl alcohol and polymethacrylic acid — harm the water flea Daphnia magna, reducing lifespan, reproduction, and causing physical deformities, raising concerns about these less-studied plastic types that dissolve in water rather than forming visible particles.

Article Tier 2

The combined effect of temperature and microplastics on Daphnia pulex Leydig, 1860 (Cladocera)

AI summary Read the abstract

Scientists found that tiny water fleas (a key food source for fish) ate significant amounts of microplastic beads, which slowed their heart rates and cut their feeding by more than half, effects that got worse in warmer water. While this study focused on aquatic life rather than humans directly, it matters because these small creatures sit at the bottom of the food chain, so microplastic pollution combined with rising water temperatures could ripple upward and affect the fish and ecosystems that eventually end up on our plates.

Article Tier 2

Antibiotic and microplastic co-exposure: Effects on Daphnia magna and implications for ecological risk assessment

AI summary Read the abstract

This review pulls together existing research on how antibiotics and microplastics, both common pollutants in lakes and rivers, affect tiny water creatures called Daphnia, which are important indicators of freshwater ecosystem health. The key takeaway: when these two pollutants combine, they appear to cause more harm together than either does alone, suggesting our current safety assessments (which typically test pollutants one at a time) may be underestimating real-world risks. While this study focused on aquatic life rather than humans directly, it matters because these same waterways often feed into our drinking water and food supply, so better understanding combined pollutant effects could help protect

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper