Topic modeling discovers trending topics in global research on the ecosystem impacts of microplastics

Abstract

Abstract The ecological threats of microplastics have sparked research worldwide. However, changes in the topics of microplastic research over time and space have not been evaluated quantitatively, making it difficult to identify the next frontiers. Here, we apply topic modeling to assess global spatiotemporal dynamics of microplastic research. We identified nine leading topics in current microplastic research. Over time, microplastic research topics have switched from aquatic to terrestrial ecosystems, from distribution to fate, from ingestion to toxicology, and from physiological toxicity to cytotoxicity and genotoxicity. In most of the nine leading topics, a disproportionate amount of independent and collaborative research activity was conducted in and between a few developed countries which is detrimental to understanding the environmental fates of microplastics in a global context. This review recognizes the urgent need for more attention to emerging topics in microplastic research, particularly in regions that are heavily impacted but currently overlooked.