Microplastics in the gastrointestinal tracts of cetaceans from the United States (NCEI Accession 0209240)

Initial study:
Microplastics (MPs, 1 µm-5 mm) are ubiquitous in the marine environment and are of growing environmental concern. Their abundance, small size, and global distribution render them highly bioavailable to a wide variety of marine organisms. Little is known about ingestion of MPs in marine top predators, such as cetaceans. The current study quantified the MP load in the gastrointestinal tract (GIT) of bottlenose dolphins stranded in South Carolina, USA from 2017-2018. GIT contents were washed into glass containers and organic material was removed using a warm base digestion. A density separation step was applied when necessary to remove sediment. Samples were filtered and dried, and MPs were enumerated under a stereomicroscope with the aid of a hot needle. MPs (125 µm – 5 mm) were detected in all GIT (N=7) of stranded bottlenose dolphins. Total MP load ranged between 123-422 among individuals. Fibers were the most abundance morphology and white/clear, black/grey, and blue were the most common color categories observed. MP research in cetaceans is challenging due to their large size, heterogeneous gut contents, and difficulty of acquiring quality samples. Findings from this investigation will aid future studies examining MP in marine apex predators like T. truncatus.



Submission Package ID: 33BGLJ