Introduction: Microplastic contamination poses significant challenges to aquatic life and human health. This study aimed to assess the presence, frequency, and characteristics of microplastics in the Blue Swimmer Crab (Portunus armatus), Banana Prawn (Penaeus merguiensis), Bivalve Mollusc Oyster (Amiantis umbonella), and Razor Shell (Solen roseomaculatus) from the coastal waters of Bandar Abbas, Persian Gulf, Iran, which provides a comprehensive analysis of microplastic contamination in these species within this area.
Methods: Five research stations along the Bandar Abbas coast, representing varying levels of urbanity, were chosen for sampling. After collecting biological samples, we isolated microplastics using a digestion procedure and flotation method. The characteristics of microplastics, including shape, color, size, and type, were analyzed with microscopy and Fourier-transform infrared spectroscopy (FTIR). Matrix-spiked (MS) samples were prepared to validate method accuracy and recovery rates. Identified microplastic forms included fibers, fragments, and films, with fibers being the most common.
Results: The particles were categorized into three size ranges: 0.45-25 μm, 25-250 μm, and 250-500 μm. Sixty-six percent fell within the 0.45-25 μm range, predominantly in black and blue colors. Common polymers included polyethylene, polypropylene, polyethylene terephthalate, polystyrene, and polyamide. The average microplastic frequency was 2.57 ± 1.2, 4.9 ± 1.95, 3.27 ± 1.2, and 4.05 ± 1.9 particles/g for Blue Swimmer Crab, Banana Prawn, Bivalve Mollusc Oyster, and Razor Shell, respectively. Correlation analysis indicated a significant positive relationship between microplastic frequency in soft tissues and body size.
Conclusion: This study highlights the presence of microplastics in key marine species in Bandar Abbas waters, posing risks to aquatic ecosystems and human health.