Microplastics in different tissues of a pelagic squid (Dosidicus gigas) in the northern Humboldt Current ecosystem

Microplastics (MPs) found in marine invertebrates have aroused great concern, but MP ingestion by cephalopods is rare. To evaluate MP contamination in commercially important pelagic squids, we examined the abundance and characteristics of MPs in the gill, intestine, and stomach of jumbo squid Dosidicus gigas (30.9 to 65.0 cm mantle length), collected from the northern Humboldt Current. The average abundance ranged from 4.0 to 7.4 items/individual and 0.2 to 0.7 items/g wet weight for the three tissues. The MPs were sized 80.75 to 4632.27 μm, with larger MPs generally found in the stomach. The majority of MPs were fibrous in shape, blue or black-gray in color, and cellophane in composition. These results revealed the MP distribution in D. gigas and could be driven by its movement pattern and habitat use. Furthermore, this study provides evidence that adherence to gills is probably an alternative means by which pelagic squid accumulate MPs.