Different Toxic Effects of Polystyrene Microplastics and Nanoplastics on Caenorhabditis elegans

ABSTRACT Exposure to polystyrene microplastics/nanoplastics (PS‐MPs/NPs) may induce severe toxic effects in organisms. This study compared the toxicity of 2‐μm PS‐MPs and 0.1‐μm PS‐NPs by using Caenorhabditis elegans ( C. elegans ) as the experimental model. The ingestion of both particles increased with increasing exposure concentration. PS‐MPs were taken up more at 0.1, 1, and 10 mg/L, while PS‐NPs were ingested more at 100 mg/L. At concentrations ≥ 1 mg/L, both PS‐MPs and PS‐NPs negatively affected the growth, locomotion, lifespan, and reproduction of C. elegans and induced oxidative stress. At concentrations of 10–100 mg/L, PS‐MPs caused greater toxicity in terms of locomotion, reproduction, and reactive oxygen species (ROS) induction. Notably, the PS‐MPs/NPs ingested by the parental generation were not transmitted to offspring. This study showed the distinct toxicological impacts of PS‐MPs and PS‐NPs on C. elegans , hence enhancing comprehension of the risks to the environment posed by MPs/NPs.