Global research trends, intellectual structure, and emerging frontiers in trace metal accumulation in marine organisms: a comprehensive analysis (1981–2026)

Abstract

Trace metal accumulation in marine organisms remains a major environmental and public health concern because metals persist in marine ecosystems, transfer through food webs and may reach humans through seafood consumption. Although research in this field has expanded substantially, its long-term development, intellectual structure, collaboration patterns and emerging research fronts have not been comprehensively mapped. This study provides a field-wide bibliometric assessment of 3039 publications retrieved from the Web of Science Core Collection, covering the period from 1981 to 15 February 2026. VOSviewer was used to analyze publication growth, source-level bibliographic coupling, citation networks, international co-authorship, co-cited references and author-keyword co-occurrence. Scientific output increased markedly after the mid-2000s and accelerated after 2015, reaching 242 publications in 2022 and 240 in 2025. China was the most productive country, whereas the USA and France showed particularly strong international collaboration. Marine Pollution Bulletin was the leading source in publication output and citation influence, while Science of the Total Environment, Environmental Pollution and Environmental Science and Pollution Research occupied central positions in the journal network. Co-citation analysis identified foundational studies linking metal bioaccumulation, seafood contamination and human health risk assessment. Keyword and overlay analyses revealed a thematic shift from conventional monitoring of metals in fish, sediments and bivalves toward integrated assessments of seafood safety, dietary exposure and human-health risk, with cancer risk, hazard index and estimated daily intake becoming increasingly prominent. These findings emphasize the need for strengthened environmental monitoring, whereas microplastic–metal interactions, stable-isotope applications and climate-related effects were interpreted as complementary emerging directions for future research. By integrating productivity, intellectual structure, collaboration and thematic evolution, this study provides a systematic reference for future Marine Pollution Research, monitoring priorities and risk-oriented Environmental Management.