Overview

• Microplastics are now confirmed to permeate the entire ocean water column, including the deepest trenches such as the Mariana Trench, where concentrations reach up to 13,500 particles per cubic meter.
• Smaller microplastic particles remain evenly suspended throughout the ocean, while larger fragments accumulate near the surface and seafloor, with the highest concentrations on continental shelves.
• The study finds microplastics constitute up to 5% of carbon particles at depths of 2,000 meters, disrupting the biological carbon pump and reducing the ocean's ability to sequester atmospheric CO2.
• Plastic-derived carbon is distorting radiocarbon dating by up to 400 years, complicating efforts to analyze historical and environmental processes.
• Researchers identified 56 polymer types in the ocean but note that inconsistent sampling methods and limited coverage hinder comprehensive quantification and understanding of microplastic impacts.