Microplastics alter multiple biological processes of marine benthic fauna

Area of Science:

• Marine Biology
• Environmental Science
• Ecotoxicology

Background:

• Marine sediments act as sinks for microplastics, leading to significant exposure of benthic organisms.
• Seabed invertebrates play crucial roles in marine ecosystem functions, including nutrient cycling and energy transfer.
• A growing body of research investigates the impacts of microplastics on marine life, necessitating comprehensive analysis.

Purpose of the Study:

• To conduct a meta-analysis of experimental studies on microplastic impacts on marine invertebrates.
• To identify general patterns and specific biological processes affected by microplastic exposure.
• To compare the effects of different microplastic types (virgin, aged, contaminated, leachates).

Main Methods:

• Meta-analysis using Hedge's effect size (g) to quantify microplastic impacts.
• Inclusion of studies examining invertebrate feeding, survival, energetics, development, and reproduction.
• Categorization of effects based on life stage, feeding habits, and microplastic characteristics.

Main Results:

• Overall negative impact of microplastics on invertebrates (g = -0.57), with embryos being most vulnerable (g = -1.47).
• Significant negative effects observed across six of seven biological processes, including survival (g = -0.69), development, and reproduction.
• Deposit feeders and omnivores exhibited pronounced negative impacts (g = -0.92 and -0.93, respectively).
• Exposure to microplastic leachates demonstrated the strongest negative effects (g = -0.93).

Conclusions:

• Microplastic pollution poses a significant and consistent threat to seabed invertebrates, impacting fundamental biological processes.
• The findings indicate potential long-term consequences for marine ecosystem functioning due to widespread microplastic contamination.
• Further research focusing on microplastic leachates and contaminants is crucial for understanding and mitigating these impacts.