Landfill microplastic research in Asia (2013–2025): Bibliometric insights into trends, contributors, and emerging hotspots

Landfill-derived microplastics (MPs) are an emerging environmental concern in Asia. Although MP pollution has received increasing scientific attention, the regional knowledge structure, leading contributors, and emerging hotspots of landfill MP research in Asia remain limited and fragmented. This study addresses this gap through a bibliometric analysis of landfill MP research in Asia from 2013 to 2025. A total of 1992 records were retrieved from the Web of Science Core Collection using a fuzzy logic search strategy. Bibliometric indicators and network-based methods were employed to examine publication growth, document types, country and institutional contributions, subject area distribution, author collaboration, and keyword co-occurrence patterns. The results reveal a rapid expansion of this research field, with annual publication output increasing from 3 records in 2013 to 491 records in 2025. The compound annual growth rate was 52.53%, with a model fit of R 2 = 0.58. Research articles accounted for 38.56% of the dataset, whereas articles represented 37.76%, indicating a relatively narrow gap between empirical and synthesis-based studies. China, India, and Malaysia became the top contributor countries. Malaysia exhibited a high level of collaboration at the author level, whereas China published a high level of research at the institutional level. The largest subject area was environmental science with 1356 publications. Keyword analysis revealed the key emerging hotspots: landfill leachate, risk assessment, bioplastics, circular economy, and health risks. The novelty of the study is that it is the first study focused in Asia that considers publication tendencies, scientific contributors, thematic evolution, and research gaps in a single bibliometric context. Thus, this study serves as a regional evidence base to help facilitate collaboration, enhance field-based monitoring, and inform future risk assessments, management, and policy development for landfills in Asia.