Acute In Vitro Effects of Polystyrene Microplastics on Cell Viability, Oxidative Status, and DNA Integrity in Zebrafish Erythrocytes

In recent decades, intensified human activities, including industrialization and urban expansion, have given rise to significant environmental challenges, with plastic pollution emerging as a critical concern. Microplastics, particularly those derived from polystyrene (PS-MPs), are widespread in soils and oceans, posing risks to biodiversity and human health through ingestion, inhalation, and contact. This study examined the detrimental impact of PS-MPs on Zebrafish-Danio rerio (Hamilton, 1822) erythrocytes. The zebrafish (Danio rerio) is a well-established model organism in biomedical research, whereas its erythrocytes served as the cellular model investigated in this study. In vitro experiments involved exposing zebrafish erythrocytes, isolated from 25 adult zebrafish, to 105 µg/mL of PS-MPs for 30, 60 and 90 min to assess cytotoxicity, genotoxicity and oxidative stress. The results revealed a time-dependent and statistically significant reduction in erythrocyte viability (−30% to −50%), genomic stability (%GTS −20% to −40%), and a concomitant increase in DNA damage (DFI ~30–38%) and ROS production (~27–35%) compared to controls (all p ≤ 0.05). These molecular disruptions related to reduced cell viability, indicating that PS-MPs are cytotoxic and genotoxic, causing genetic damage and oxidative imbalance. The results obtained confirmed the toxicity of PS-MPs. These data suggest that PS-MPs can interfere with genetic material by inducing apoptosis through oxidative imbalance.