Global assessment of fibrous microplastic pollution: Sources, environmental distribution, and ecological impacts

Microplastic pollution is an emerging global concern, with fibrous microplastics (FMPs) representing a dominant class that poses a particular danger due to their persistence and high aspect ratios. FMPs originate from both industrial and consumer activities, with wastewater treatment plants acting as a major transmission pathway. Despite extensive research on microplastics, a morphology-focused understanding of FMP sources, transport pathways, environmental fate, and biological impacts has remained limited. The present study integrates a systematic literature synthesis with a bibliometric analysis using VOSviewer to identify global research hotspots and trends on FMPs. Bibliometric analysis shows that 80% of publications have been led by China, the United States, and European countries in the past 5 years. Thematic clustering reveals textiles, polyester fibers, and wastewater systems as dominant research nodes. Global studies reported a 6.3-fold increase in the production of synthetic microfibers between 1980 and 2015, with the laundering of textiles projected to release over 22 million tonnes of microplastic fibers between 2015 and 2050. Across both industrial and municipal wastewater treatment systems, FMPs consistently emerge as the dominant morphology, accounting for 50%-92% of detected microplastics in treated effluents. This review also identifies a conserved tri-modal impact pattern of FMP exposure, mechanical disruption, oxidative inflammatory activation, and chemical vectoring, highlighting fiber morphology as a critical determinant of ecological and physiological vulnerability across biodiversity. In conclusion, this comprehensive review aims to contribute to the existing scholarship of FMPs and urges the development of strategies, sustainable textile innovations, and targeted research on FMPs and advanced removal technologies to limit their environmental footprint.