Effect of Polystyrene Microplastics Exposure on Blood Parameters in Mice

Microplastics are emerging environmental contaminants capable of crossing epithelial barriers and circulating systemically, potentially affecting organisms, including humans. This study investigated the hematological and biochemical effects of subchronic oral exposure to polystyrene microplastics (PS-MPs) in male Swiss albino mice. Animals received 1 μm PS-MPs in drinking water at 0.01 mg/day for four weeks, followed by a two-week recovery period. Blood samples were collected weekly for analysis. PS-MP exposure increased white blood cell, lymphocyte, and granulocyte counts, with a reduced monocyte percentage after the first week, and a significant rise in platelet count by week six. Elevated alanine and aspartate aminotransferase activities indicated hepatic injury, while altered urea and creatinine levels suggested renal impairment. No significant recovery was observed after PS-MP withdrawal. These findings demonstrate that subchronic oral PS-MP exposure induces inflammatory responses and disrupts liver and kidney function.