Polyamide microplastics can mitigate the effects of pathogenic bacterium on the health of marine mussels

Area of Science:

• Environmental Science
• Marine Biology
• Ecotoxicology

Background:

• Ocean pollution by Vibrio parahaemolyticus and microplastics poses a threat to marine life, particularly bivalves.
• Bacteria form harmful biofilms on microplastics, exacerbating risks to aquatic organisms.

Purpose of the Study:

• To investigate the interaction between polyamide microplastics (PA) and Vibrio parahaemolyticus.
• To assess the combined impact of PA microplastics and V. parahaemolyticus on thick-shelled mussels (Mytilus coruscus).

Main Methods:

• V. parahaemolyticus growth and biofilm formation were observed in varying PA concentrations (0-500 particles/L) over 14-48 hours.
• Mussel responses were monitored across four treatments: control, PA alone, V. parahaemolyticus alone, and co-exposure, over 14 days.

Main Results:

• Microplastics were found to suppress V. parahaemolyticus biofilm formation and virulence gene expression.
• Combined exposure to PA microplastics and V. parahaemolyticus induced immune dysregulation, intestinal damage, and microbiome disruption in mussels.
• V. parahaemolyticus alone had a more severe impact on mussels than microplastics alone, but coexistence mitigated some negative effects.

Conclusions:

• This study is the first to explore the interaction between microplastics and V. parahaemolyticus in a marine environment.
• The findings provide crucial insights into the complex ecological risks associated with co-occurring pollutants in marine ecosystems.