en عمومى General مقاله اصیل Original Article <div style="text-align: justify;">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.<br> 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.<br> Results: The particles were categorized into three size ranges: 0.45-25 &mu;m, 25-250 &mu;m, and 250-500 &mu;m. Sixty-six percent fell within the 0.45-25 &mu;m range, predominantly in black and blue colors. Common polymers included polyethylene, polypropylene, polyethylene terephthalate, polystyrene, and polyamide. The average microplastic frequency was 2.57 &plusmn; 1.2, 4.9 &plusmn; 1.95, 3.27 &plusmn; 1.2, and 4.05 &plusmn; 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.<br> Conclusion: This study highlights the presence of microplastics in key marine species in Bandar Abbas waters, posing risks to aquatic ecosystems and human health.</div> Microplastics, Ecosystem, Persian Gulf, Crustaceans, Molluscs 1 10 http://ehemj.com/browse.php?a_code=A-10-1-443&slc_lang=en&sid=1 Somayeh Enayati senayati59@yahoo.com 100319475328460021903 100319475328460021903 No Department of Environmental Sciences, BA.C., Islamic Azad University, Bandar Abbas, Iran Hossein Parvaresh hosseinp1@iau.ac.ir 100319475328460021904 0009-0002-9050-6293 Yes Correspondence to: Department of Environmental Sciences, BA.C., Islamic Azad University, Bandar Abbas, Iran Mahnaz Kerdgari m_kerdgar@yahoo.com 100319475328460021905 100319475328460021905 No Department of Marine Biology, BA.C., Islamic Azad University, Bandar Abbas, Iran Saber Ghasemi saberghasemi@gmail.com 100319475328460021906 100319475328460021906 No Department of Environmental Sciences, BA.C., Islamic Azad University, Bandar Abbas, Iran Mohsen Dehghani Ghanatghestani dehghani933@gmail.com 100319475328460021907 100319475328460021907 No Department of Environmental Sciences, BA.C., Islamic Azad University, Bandar Abbas, Iran