We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Impacts des nanoplastiques et microplastiques sur les premiers stades de vie (gamètes, embryons, larves) de l'huître creuse Crassostrea gigas
AI summary Read the abstract
This French thesis investigated the toxicity of micro- and nanoplastics on early life stages of the Pacific oyster (Crassostrea gigas), from gametes through larvae. Nanoplastics (50 nm) were more toxic than microplastics due to their high surface area, causing dose-dependent effects on fertilization success and larval development in this key coastal species.
For 70 years, mismanaged plastic waste accumulates in the oceans. Risk assessment of this contamination is a major concern, especially regarding micro- and presumably nanoplastics (MNP; <5 mm) which are bioavailable for most marine species. The objective of this thesis was to assess adverse effects of MNP to early life stages of the oyster Crassostrea gigas, a key engineer species in coastal ecosystems. MNP toxicity on oyster young stages depended on the particle size. The high surface area- to - volume ratio of polystyrene nanobeads (nano- PS; 50 nm) promoted their reactivity and interactions with biological membranes of gametes and embryos, leading to an inhibition of the fertilization and embryogenesis success while 0.5 and 2 μm polystyrene beads had any detectable effects. The nano-PS toxicity depended on the particle surface properties (e.g. surface functionalization and charge) which govern their aggregation in seawater and affinity with biological membranes. Furthermore, cationic nano- PS which remained at nanometric scale in seawater, had the highest toxic potential to oyster gametes and embryos. Embryonic exposure to these particles at a non-lethal dose reduced first generation larval performances and modulated larval growth at the second generation in response to the same embryonic exposure. All adverse effects were observed at supposedly unrealistic environmental concentrations (no in situ data exists on NP), suggesting low risk of polystyrene beads to oyster early life stages. Future studies will have to take into account the complexity and reality of MNP in oceans (e.g. polymer and shape diversity, concentrations, contaminants adsorption) to assess effects on bivalve species across generations in order to establish more accurately the risks for coastal environments.
More Papers Like This
Impacts of micro- and nanoplastics on early life stages of the Pacific oyster Crassostrea gigas
AI summary Read the abstract
This French-language thesis (a companion to the English version) examines micro- and nanoplastic impacts on early life stages of the oyster Crassostrea gigas, finding that 50 nm polystyrene nanobeads caused inhibition of fertilization and embryogenesis while larger microspheres had no visible effects. Cationic nano-PS particles showed the highest toxicity, driven by their surface properties and affinity for biological membranes, with multigenerational effects observed at environmentally plausible concentrations.
Impact of nano- and micro-sized polystyrene beads on larval survival and growth of the Pacific oyster Crassostrea gigas.
AI summary Read the abstract
Polystyrene beads at nano (0.55 um) and micro (10, 100 um) sizes were tested on Pacific oyster larvae, with smaller particles causing greater mortality and growth inhibition at lower concentrations, suggesting nanoplastics pose a higher risk to early bivalve development than microplastics.
Nanoplastics impaired oyster free living stages, gametes and embryos
AI summary Read the abstract
Researchers performed dose-response experiments exposing oyster gametes and embryos to nanoplastics and found significant impairment of fertilization success, embryo development, and larval survival. The study suggests that nanoplastic contamination could threaten bivalve reproduction by disrupting the most vulnerable free-living life stages.
Ingestion of Nanoplastics and Microplastics by Pacific Oyster Larvae
AI summary Read the abstract
Researchers tested whether Pacific oyster larvae could ingest nanoplastics and microplastics, and what effects this had on their development. They found that larvae consumed plastics as small as 100 nanometers, and exposure to the smallest particles significantly reduced larval growth and survival. The study highlights that the earliest life stages of commercially important shellfish may be especially vulnerable to nanoplastic pollution in coastal waters.
Physiological impacts of microplastics on the Pacific oyster Crassostrea gigas: The role of particle size and concentration
AI summary Read the abstract
Laboratory experiments on Pacific oysters exposed to microplastics of varying sizes and concentrations found decreased survival rates, increased oxygen consumption, and histological damage to digestive and gill tissues, with effects scaling with concentration. Oysters are global seafood staples and efficient bioaccumulators, meaning physiological damage at environmentally relevant concentrations translates directly into concerns about both aquatic ecosystem health and the safety of oysters in the human diet.
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.