The Contamination of Microplastic Debris in Blue Swimming Crab Portunus pelagicus (Linnaeus, 1758) from Artisanal Fisheries in the Eastern Gulf of Thailand

Microplastics have become a significant concern for human health, primarily because aquatic animals can ingest these particles, which then enter the human food chain. Crabs (<i>Portunus pelagicus</i>) were collected along the coastline of Rayong Province in January, April, and August 2024. Crabs were then examined for MP contamination. Our results revealed that MPs were present at all sampling sites, with a detection rate of 62.5% in external body parts and 72.2% in internal body parts. The gut was the most contaminated tissue, followed by the gills, while no MPs were found in the hepatopancreas or muscle tissues. Although overall MP detection and contamination levels were similar across sites, significant differences in abundance were observed between seasons (<i>p</i> < 0.05), with August showing the highest contamination levels. Polyethylene terephthalate glycol was the most common polymer detected, followed by nylon, polypropylene, polyethylene, polystyrene, and polyester. Anthropogenic and fishing activities contribute significantly to MP pollution in these crabs. Fibers from household laundry, followed by damaged fishing gear, are major sources of MP pollution. Enhancing the quality and durability of fishing equipment is crucial to reducing the amount of abandoned fishing gear that may be ingested by marine organisms, while the proper collection and management of discarded gear in the ocean should also be emphasized.