Three decades of microcystin-LR removal in aquatic environments: physical, chemical and biological strategies for environmental detoxification

Abstract

Abstract Microcystin-LR (MC-LR) contamination from cyanobacterial blooms poses a persistent threat to aquatic ecosystems and human health, necessitating effective removal technologies. This study used visualization analyses to examine global research on MC-LR removal in aquatic environments over the past three decades. A total of 978 publications from the Web of Science Core Collection, published from 1993 to August 2025, were analysed. Annual output increased slowly from 1993 to 2003, accelerated thereafter, and remained high after 2020, indicating that research activity entered a relatively stable phase following a period of rapid growth. Water Research, Chemosphere, Chemical Engineering Journal, Journal of Hazardous Materials, and Environmental Science & Technology were identified as leading journals, while China and the United States dominated research output and formed the central axis of international collaboration. Keyword and co-citation analyses showed that physical adsorption, photocatalysis, advanced oxidation processes and biodegradation are the main removal pathways. The field has diversified from early adsorption-assisted removal and conventional oxidation toward mechanism-driven and material-enabled strategies, while microbial degradation has remained an important parallel research direction. Findings suggest future progress should prioritize standardized evaluation of removal and detoxification efficiency, transformation-product toxicity, material regeneration, cost and scalability, thereby supporting reliable and practical cyanotoxin control.