Microplastic toxicity in aquatic organisms across phylogeny

Microplastic (MP) contamination of aquatic ecosystem had been escalated several folds and became concerning for the inhabiting organisms. Their accumulation in aquatic biota, ranging from lower invertebrates to higher vertebrates, underscores the severity of their toxicological impact and raises critical concerns for ecosystem health. Many of the researchers concentrated on assessment of MP distribution across environmental compartments and analysis of the physicochemical characteristics and their bioaccumulation in freshwater and marine species. Current review provides a comprehensive information on toxicological outcomes across various aquatic phyla exposed to MP polymers. This review collates evidence from diverse studies documenting MP-induced toxic responses, such as genotoxicity, reproductive toxicity, behavioural alterations and oxidative stress in different aquatic metazoans. Additionally, it highlights the role of MPs as vectors of xenobiotics and harmful pathogenic microorganisms, further amplifying their toxic potential on aquatic biota. Reports of physiological toxicity of MPs were reviewed phylogenetically including the extant invertebrates, protochordates and chordates. Our review is the first cross-phylum assessment of MP toxicity. We analysed pollutant vector effects on organisms including invertebrates and vertebrates. Cross species comparisons were made in relation to the perspectives of evolutionary toxicology. This review presents an indepth report of MP toxicity across phylogeny. Whereas, the previous reviews center around single phylum. This review would provide a rich and holistic information base of MP toxicity in the organisms of aquatic ecosystem.