Microplastic ingestion ubiquitous in marine turtles

Area of Science:

• Marine Biology
• Environmental Science
• Ecotoxicology

Background:

• Microplastic pollution is a growing environmental concern, yet data on its prevalence in large marine vertebrates is limited.
• Marine turtles are vulnerable to microplastic ingestion due to their feeding habits and habitat range.

Purpose of the Study:

• To investigate the presence and characteristics of synthetic particles in marine turtle ingesta.
• To determine the types, colors, and materials of microplastics found in different marine turtle species and ocean basins.

Main Methods:

• An optimized enzymatic digestion method was used to isolate synthetic particles from marine turtle gastrointestinal tracts.
• Particles were quantified, categorized by type (fibers, fragments, microbeads) and color.
• Fourier transform infrared spectroscopy (FT-IR) was employed to identify the polymer composition of a subset of particles.

Main Results:

• Synthetic particles were detected in all 102 marine turtles examined, representing all seven species and three ocean basins (Atlantic, Mediterranean, Pacific).
• Fibers constituted the majority of particles, with blue and black being the dominant colors.
• Microbeads were identified for the first time in marine megavertebrates (Pacific samples).
• FT-IR analysis revealed diverse synthetic materials including elastomers, thermoplastics, and synthetic regenerated cellulosic fibers (SRCF).

Conclusions:

• Marine turtles are ubiquitously exposed to synthetic particles, with ingestion occurring across species, trophic levels, and ocean basins.
• Multiple ingestion pathways, including direct consumption of polluted seawater/sediments and trophic transfer, are likely.
• The widespread presence of microplastics warrants further investigation into their conservation impact on marine megafauna.