Microplastic Abundance in Gastrointestinal and Gill Tissues of Siganus vermiculatus Landed at Fish Landing Port, Palopo City, South Sulawesi Indonesia

Henny Tribuana Cinnawara (Department of Aquaculture, Faculty of Fisheries, Universitas Andi Djemma, Palopo, Indonesia)
Seto Sugianto Prabowo Rahardjo (Department of Aquaculture, Faculty of Fisheries and Marine Science, Universitas Brawijaya, Malang, Indonesia)
Andi Mi’rajusysyakur Muchlis (Department of Aquaculture, Faculty of Fisheries, Universitas Andi Djemma, Palopo, Indonesia)
Wardha Isjayanti (Fisheries Science Study Program, Graduate Program, Universitas Andi Djemma, Palopo, Indonesia)
Mohammad Afdhal Adidharma (Department of Marine Science, Institut Teknologi dan Bisnis Muhammadiyah Kolaka, Indonesia)

Journal of Fisheries & Marine
2026: IN PRESS ISSUE (JUST ACCEPTED MANUSCRIPT, 2026)

Graphical Abstract Highlight Research Microplastics were detected in 100% of S. vermiculatus, indicating widespread contamination in the coastal waters of Bone Bay. Microplastic abundance was significantly higher in the gills than in the stomach, suggesting the respiratory tract as the primary route of microplastic exposure. Fiber-like microplastics predominated in both tissues, indicating a strong contribution from fishing activities and synthetic textile sources. FTIR analysis identified a variety of polymers (PE, PA, PES, PP, and HDPE), indicating multiple anthropogenic sources of microplastic pollution.   Abstract Microplastic contamination in coastal ecosystems has become an environmental issue attracting attention due to its potential impact on humans through marine food. This study aims to analyze the abundance, characteristics, and composition of microplastic polymers in the consumption fish Siganus vermiculatus landed at the Palopo Fish Landing Port. Fifteen fish samples were examined, and microplastics from gill and stomach tissues were isolated through chemical digestion, observed under a stereomicroscope, and characterized by shape, color, and size. Polymer types were identified using Fourier Transform Infrared Spectroscopy (FTIR) with a spectral similarity level of ≥70%. Microplastics were detected in all samples (100%) with a total abundance of 107 particles (64 in gills, 43 in stomach). Their abundance was higher in the gills (4.27±1.44 MPs/Ind) than in the stomach (2.87±0.99 MPs/Ind), suggesting respiratory uptake as the primary exposure pathway. Fibers predominated (76.56% in gills; 79.07% in stomach), followed by films and fragments. White and blue particles were most abundant, indicating inputs from domestic waste and fisheries activities. Size distribution was dominated by 1-5 mm particles (56.25%), followed by <1 mm (40.63%). Identified polymers included polyethylene (PE), polyamide (PA), polyester (PES), polypropylene (PP), and high-density polyethylene (HDPE), reflecting diverse anthropogenic sources. These results confirm significant microplastic contamination of the edible fish S. vermiculatus from the Palopo City fish landing port. This finding indicates potential microplastic contamination in the benthic ecosystem and coral reefs in Bone Bay, and further research is needed to confirm this suspicion.