Toxicological and ecological impact of microplastics across major invertebrate phyla: a bibliometric review

Background and Aim Invertebrates serve as important bioindicators for assessing the toxicological risk of environmental contaminants, including microplastics, due to their significant ecological roles and sensitivity to pollution. The study aims to fill gaps in existing research by combining quantitative bibliometric analysis with a qualitative, phylum-level synthesis of global research on microplastics in invertebrates. This will help us look at research trends, taxonomic biases, and knowledge gaps.Review Approach A total of 498 documents on “Microplastics in Invertebrates” published between 2013 and 2024 from the Scopus database were analyzed using bibliometric methods through VOSviewer. Additionally, an overlay analysis of “Invertebrate toxicity” was performed using 72,279 documents (2010–2024) to identify emerging research trends.Key Findings and Conclusions The keyword “microplastics,” had the strongest association with "pollution", and "toxicity". Research predominantly focused on Mollusca, Arthropoda, as reflected by keywords“bivalve,” “bivalves,” “oyster”,and "Crustacea", indicating taxonomic bias. The coauthored countries’ networks show increased international collaboration, with China (leading), Italy, Germany, the United Kingdom, and the United States as the top five countries. The University of Chinese Academy of Sciences is a leading contributor in this domain. An overlay analysis shows “toxicity” as the dominant keyword, but “microplastics” has emerged as a core keyword in recent years. Environmental Science ranks first in the subject area. Publication trends emphasized gradual progression over the decade, peaking in 2024, while the geographic distribution of publications reveals that worldwide investigation is necessary.This review identifies key research themes and taxonomic bias toward Mollusca and Arthropoda, highlighting an emerging focus on “microplastics” in recent years and the need for broader global research attention on invertebrates.Impact Statement This is the first bibliometric review on the presence of microplastics in all major invertebrate phyla. Invertebrates serve as vital ecological indicators, and understanding their interaction with microplastics is significant. By mapping the research trends using bibliometric analysis, this study provides an overview of current knowledge in this area. A detailed dataset on microplastic prevalence in key invertebrate phyla can be utilized for evaluating ecosystem health, filter feeding dominates microplastic ingestion in bivalves, which also affects human health via trophic transfer. This review also highlights critical research gaps for future exploration, will aid policymakers in developing ecosystem-specific pollution control strategies.