Quantification, identification, and chemical characterization of microplastics (MPs) in commercial fishes from the Palk Strait, Southeast India

Abstract
The present study examined the quantification, identification, and their characterization of microplastics (MPs) in the tissues and guts of commercially important fishes from the Palk Strait, Southeast India. A total of 75 specimens representing 10 species were collected from local landing centres. Morphological characterization of MPs, including size, colour, and shape, was performed using a stereomicroscope. In total, 115 MPs/ind. were recorded, with fibres being the predominant type (51 %), followed by fragments (29 %) and films (20 %). The MPs detected ranged in size from 0.1 to 1.0 mm. Fish guts and tissues had mostly black (47%), blue (22%), and colourless (20%) MPs, while green, violet, and red were less common. Fourier-transform infrared spectroscopy (FTIR) analysis identified polyethylene (PE) and polypropylene (PP) as the main polymers. The presence of MPs in edible fish tissues suggests their possible entry into the human body via seafood consumption, underscoring the necessity for comprehensive risk assessment.