Related Experiment Video
Updated: Dec 12, 2025
A Toxicological and Ecotoxicological Assay Based on Mussel (Mytilus galloprovincialis) Hemocytes Motility
Published on: December 13, 2024
Impacts of microplastics exposure on mussel (Mytilus edulis) gut microbiota
Luen-Luen Li1, Rachid Amara2, Sami Souissi3
1Univ. Littoral Côte d'Opale, CNRS, Univ. Lille, UMR 8187, LOG, Laboratoire d'Océanologie et de Géosciences, F 62930 Wimereux, France; ANSES, Laboratoire de Sécurité des Aliments, Boulevard du Bassin Napoléon, 62200 Boulogne-sur-mer, France.
Abstract:
Microplastics (MPs), plastics with particles smaller than 5 mm, have been found almost in every corner of the world, especially in the ocean. Due to the small size, MPs can be ingested by animals and enter the marine trophic chain. MPs can affect animal health by physically causing damage to the digestive tract, leaking plastic chemical components, and carrying environmental pollutants and pathogens into animals. In this study, impacts of MPs ingestion on gut microbiota were investigated. Filter feeding mussels were exposed to "virgin" and "weathered" MPs at relatively realistic concentration 0.2 mg L-1 ("low") and exaggerated concentration 20 mg L-1 ("high") for 6 weeks. Influence in mussel gut microbiota was investigated with 16S rRNA gene high-throughput sequencing. As compared with non-exposed mussels, alteration of gut microbiota was observed after mussels were exposed to MPs for 1 week, 3 weeks, 6 weeks, and even after 8-day post-exposure depuration. Potential human pathogens were found among operational taxonomic units (OTUs) with increased abundance induced by MP-exposure. Faecal pellets containing microorganisms from altered gut microbiota and MPs might further influence microbiota of surrounding environment. Our results have demonstrated impacts of MP-exposure on mussel gut microbiota and suggested possible consequent effects on food quality, food safety, and the well-being of marine food web in the ecosystem for future studies.
Insights
Microplastic (MP) ingestion alters mussel gut microbiota, even after depuration. This contamination introduces potential human pathogens, impacting marine food webs and food safety.
Area of Science:
- Marine Biology
- Environmental Science
- Microbiology
Background:
- Microplastics (MPs) are pervasive environmental contaminants, particularly in marine ecosystems.
- Their small size facilitates ingestion by marine organisms, leading to entry into the food chain.
- MPs pose risks through physical damage, chemical leaching, and pathogen transport.
Purpose of the Study:
- To investigate the impact of microplastic ingestion on the gut microbiota of filter-feeding mussels.
- To assess the effects of different microplastic types (virgin and weathered) and concentrations (low and high) over time.
Main Methods:
- Mussels were exposed to "virgin" and "weathered" microplastics at "low" (0.2 mg L⁻¹) and "high" (20 mg L⁻¹) concentrations for six weeks.
- Gut microbiota composition was analyzed using 16S rRNA gene high-throughput sequencing.
- Microbiota changes were monitored throughout the exposure period and after an eight-day depuration phase.
Main Results:
- Microplastic exposure significantly altered mussel gut microbiota composition within one week.
- These alterations persisted even after a depuration period.
- Operational taxonomic units (OTUs) identified as potential human pathogens increased in abundance due to microplastic exposure.
Conclusions:
- Microplastic ingestion demonstrably impacts the gut microbiota of mussels.
- Altered gut microbiota and microplastics in fecal pellets can affect surrounding environments.
- Findings suggest potential risks to food quality, food safety, and marine ecosystem health.
