Microplastic emissions from fishing ropes: Quantification, characteristics, and implications for marine pollution

This study quantifies and characterizes microplastics generated through the mechanical abrasion of fishing ropes, a significant yet often overlooked source of marine microplastic pollution. A custom-designed hauler system was used to evaluate the quantity, size distribution, and morphology of microplastics released from polypropylene-based co-polymer ropes under varying hauling weights (5–50 kg) and operational frequencies (1–20 cycles). The results indicated that 92 ± 3% of the released microplastics were non-fiber fragments, closely resembling those observed in Korean coastal waters. A linear regression analysis revealed that each 1 kg increase in hauling weight produced an additional 1.383 microplastic particles per meter. Global estimates suggest that abrasion from new ropes releases approximately 768 trillion microplastic particles (2.8 kilotons) annually. These findings emphasize the substantial contribution of fishing gear abrasion to marine microplastic pollution. Future research is needed to explore polymer-specific fragmentation, environmental weathering, and the fate of particles to refine emission estimates.