Toxicological impact of polyvinyl chloride microplastic-contaminated food: Evidence from a mouse model

Microplastic pollution has emerged as a critical environmental and public health concern, induced by the widespread presence and toxicity of various polymers across diverse environments, food systems, and animal bodies. However, the toxicological assessment of polyvinyl chloride (PVC) is still limited to a narrow range of animal groups. In this study, we evaluated the effect of dietary exposure to different concentrations (5%, 10% and 15%) of PVC microplastics (∼125 μm) in mice over a 13-week period. Exposure to high concentrations (10% and 15%) of microplastics adversely affected growth, blood cell morphology, oxidative stress biomarker, and induced the histopathological changes of the liver, intestine, and kidney, though microplastic accumulation was solely observed in gut tissue. High concentration of microplastics significantly reduced the growth but markedly elevated the hepatosomatic index in mice. The red blood cells of treated groups appeared abnormal in shape, while no significant difference was found in the total blood cell count. Among the oxidative stress biomarkers, serum superoxide dismutase (SOD) concentration was significantly lower in the blood serum of treated mice. In addition, treatment with higher concentrations of PVC microplastics triggered vascular congestion and hepatocyte vacuolization in liver, glomerular atrophy in kidney, and altered crypt cell structure in intestine of mice. Thus, this study provides important insights into the consequences of PVC microplastic exposure in mammalian organisms, including humans, and carries significant implications for mitigating microplastic contamination in food systems.