We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Quantifying Polyethylene Microplastics Through Microscopy and Investigating Their Effects on Daphnia magna Growth Rate
AI summary Read the abstract
Researchers used a microscope to detect tiny polyethylene plastic beads in water fleas (Daphnia magna), finding plastic particles in most digested specimens tested. When juvenile Daphnia were fed algae with or without microplastics, growth rates and survival varied between groups, but results were inconclusive due to small sample sizes and high death rates in some groups.
Polyethylene microplastics are among the most abundant pollutants in freshwater environments (Schwarz et. al. 2019). Their ingestion by aquatic organisms has been linked to physiological stress and potential bioaccumulation across trophic levels (Nelms et. al. 2018). This study investigates whether green-fluorescing, low-density polyethylene microspheres can be reliably quantified within Daphnia magna using polarizing light microscopy, and whether exposure affects juvenile growth rates. Two colonies were maintained, with microspheres integrated in algae and water columns as the treatment group. Both live and digested Daphnia specimens were analyzed using an Olympus BX51 Polarizing Light Microscope. Microspheres were detected in 47 of 60 digested individuals (average 5.317±5.691 particles), with particles observed in the digestive tract and carapace of all live specimens. Polarizing light microscopy proved effective for microplastic detection, though it was time-intensive. Growth rate effects were tested by placing juveniles into individual vials containing either just algae (control) or algae mixed with the microspheres (treatment) and the lengths were measured every other day for two weeks. Three experimental groups were tested: control-control, control-plastic, and plastic-plastic. Unexpectedly, Daphnia exposed in the plastic-plastic group exhibited the highest growth rates (1.150±1.344 mm/day). However, these results were inconclusive due to limited replication and high mortality in the control-control and control-plastic groups (2–4 days) compared to the plastic-plastic group (10–14 days). Future work includes measuring microplastic diameters, exploring alternative analytical methods, and assessing energy trade-offs and potential additive leachates (Labbe et. al. 2020) (Schrank et. al. 2019).
More Papers Like This
Effect of Polystyrene Microplastics in Different Diet Combinations on Survival, Growth and Reproduction Rates of the Water Flea (Daphnia magna)
AI summary Read the abstract
Researchers exposed Daphnia magna water fleas to 6-micrometer fluorescent polystyrene microplastics across different diet combinations over 21 days, finding that animals fed only microplastics showed survival declines similar to starved controls and the least growth, while algae co-feeding partially mitigated but did not eliminate reproductive impacts.
The effect of microplastics on the speed, mortality rate, and swimming patterns of Daphnia Magna
AI summary Read the abstract
This study compared how polystyrene and polyethylene microplastics affect the swimming speed, mortality, and movement patterns of Daphnia magna water fleas, finding both plastics caused behavioral changes. Daphnia are key animals in freshwater food webs, and microplastic-induced behavioral impairment could affect their role in aquatic ecosystems.
Consumption and Impacts of Water-Borne Polypropylene Microplastics on Daphnia Similis
AI summary Read the abstract
This study exposed water fleas (Daphnia similis) to polypropylene microplastics and found that the particles accumulated in their digestive tracts and disrupted biochemical processes. Polypropylene is one of the most common plastics in consumer packaging, making it a major contributor to microplastic pollution in aquatic environments. Daphnia are a key link in aquatic food chains, so their disruption could affect fish and other wildlife that consume them.
Ingestion and Egestion of Microplastics by the Cladoceran Daphnia magna: Effects of Regular and Irregular Shaped Plastic and Sorbed Phenanthrene
AI summary Read the abstract
Researchers studied how the water flea Daphnia magna ingests and excretes polyethylene microplastics of different shapes and sizes. They found that irregular-shaped fragments were ingested differently than regular beads, and that neither type caused acute mortality at tested concentrations — but the study raises questions about chronic effects in this key freshwater species.
The Effects of Natural and Anthropogenic Microparticles on Individual Fitness in Daphnia magna
AI summary Read the abstract
Researchers compared the effects of natural and anthropogenic microparticles on the fitness of the water flea Daphnia magna. The study found that both primary microplastics from cosmetic products and secondary microplastics from degraded plastic waste can have detrimental effects on zooplankton feeding and fitness, with particle shape and weathering influencing toxicity.
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.