We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Species-specific bioaccessibility of microplastics by benthic macroinvertebrates.
AI summary Read the abstract
Researchers tested how 11 types of freshwater and marine invertebrates, including worms, snails, clams and mussels, ingested a mixture of different-sized microplastic particles in lab experiments. The amount and size of plastic found in each animal varied by species, with most ingested particles measuring between about 5.5 and 27.7 micrometers, and animals egested more particles than remained in their bodies after 24 hours.
Effect and bioaccumulation tests have mainly used monodisperse microplastics, whereas natural microplastics are diverse. Consequently, understanding of their actual biological accessibility remains limited, which constrains risk assessment. The goal of this study was to investigate species-specific uptake of an environmentally representative microplastic mixture (ERMP; 9-5386 μm; PE, PP, PET and PS) in 11 freshwater and marine benthic macroinvertebrate species. Species-specific uptake was assessed by describing ingested particles as a continuum through continuous size distributions and comparing these distributions among species and against controls. Samples underwent enzymatic/hydrogen peroxide digestion and FTIR microscopy, followed by polymer- and size-specific blank correction. Adverse effects previously observed in the freshwater worm Lumbriculus variegatus could be linked more directly to exposure because microplastics were detected in post-depuration organism samples. Only a select fraction of the ERMP mixture was ingested by Asellus aquaticus, Corbicula fluminalis, Corophium volutator, Hyalella azteca, L. variegatus, Limecola balthica, Mytilus edulis and Tubifex spp. Most particles detected in organisms ranged from 5.5 to 27.7 μm and differed in polymer composition among species; 5.5 μm was also the method's lower size-detection limit. Egested ERMP significantly exceeded particles remaining in post-depuration organism samples, indicating substantial egestion during the 24 h depuration period. The lowest ERMP numbers occurred in post-depuration organism samples of the midge larva Chironomus riparius and egestion samples of the mud snail Potamopyrgus antipodarum, respectively, averaging <1 particle/organism. The highest egested count occurred in the mussel M. edulis, at 49.9 particles/organism, primarily polystyrene. Similar size distributions were found for the amphipods A. aquaticus and H. azteca, both sediment grazers/scavengers, and for the clams C. fluminalis and L. balthica, both facultative deposit feeders. These particle size- and species-specific ingestion patterns provide a basis for understanding effect mechanisms such as particle volume-based food dilution.
More Papers Like This
Fate and effects of an environmentally relevant mixture of microplastics in simple freshwater microcosms
AI summary Read the abstract
Researchers tested how a realistic mixture of different microplastic types affects freshwater invertebrates in indoor ecosystems over 28 days. The study found that worms and snails consumed microplastics in sizes related to their mouth dimensions, and while the plastics settled and moved through the water in predictable patterns, no significant harmful effects on the animals were observed at the concentrations tested.
Microplastic ingestion in aquatic and soil biota: A comprehensive review of laboratory studies on edible size and intake pattern
AI summary Read the abstract
This comprehensive review of 169 lab studies found that microplastics smaller than 300 micrometers can be consumed by a wide range of aquatic and soil organisms at the base of the food chain. Even organisms as small as 1 micrometer in body size were found to ingest microplastics. Since these tiny creatures are the foundation of food webs, their consumption of microplastics creates a direct pathway for plastic particles to accumulate up the chain and eventually reach humans through food.
Microplastic accumulation and ecological impacts on benthic invertebrates: Insights from a microcosm experiment
AI summary Read the abstract
In a month-long experiment, researchers exposed marine invertebrates like mussels and clams to small microplastics and found that the particles accumulated mainly in the gut, gills, and reproductive organs. Different species absorbed different types and sizes of microplastics, and bottom-dwelling organisms suffered energy loss from the exposure. Since many of these species are consumed as seafood, their microplastic accumulation represents a direct pathway for human exposure.
Species-specific effects of long-term microplastic exposure on the population growth of nematodes, with a focus on microplastic ingestion
AI summary Read the abstract
Scientists conducted long-term microplastic exposure experiments on freshwater nematode species and found species-specific effects on population growth, with ingestion rates and harm varying substantially across species despite identical exposure conditions.
Sampling, isolating and identifying microplastics ingested by fish and invertebrates
AI summary Read the abstract
This study reviewed sampling and identification methods for microplastics ingested by fish and invertebrates, evaluating each approach for accuracy, reproducibility, and applicability to different species and sample types.
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.