Work

Low pH aggravates the toxicity of polystyrene microplastics in crab Eriocheir sinensis: Evidence from metabolome and intestinal microflora

Year: 2025

Type: article

Abstract: Microplastics (MPs) pollution and freshwater acidification represent emerging threats to aquatic ecosystems. The combined toxic effects of these stressors on crustaceans and their underlying immune-metabolic mechanisms remain poorly understood. This study investigated the individual and combined toxic effects of low pH and polystyrene MPs on the Chinese mitten crab ( Eriocheir sinensis ). Through a 21-day exposure experiment combined with enzyme activity analysis, gut microbiota profiling, and hepatopancreas metabolomics, the findings revealed: (1) Combined exposure to low pH (pH 6.5) and MPs exacerbated oxidative damage and immune suppression, demonstrating synergistic toxicity; (2) MPs alone primarily affected pyrimidine metabolism, whereas combined exposure significantly disrupted the tricarboxylic acid (TCA) cycle and arginine biosynthesis while activating serotonin metabolism; (3) Although the α-diversity of gut microbiota remained stable, its COG functional profile underwent significant alterations. The results indicate that freshwater acidification amplifies the toxic effects of MPs on crustaceans through immune-metabolic interactions, highlighting the urgency of assessing multiple environmental stressors in the context of climate change. The study provides novel mechanistic insights for aquatic ecological risk assessment.

Source: Environmental Chemistry and Ecotoxicology

DOI: 10.1016/j.enceco.2025.05.015