Uptake of nanopolystyrene particles induces distinct metabolic profiles and toxic effects in Caenorhabditis elegans.

Nanoplastics are widely used in modern life, for example, in cosmetics and daily use products, and are attracting concern due to their potential toxic effects on environments. In this study, the uptake of nanopolystyrene particles by Caenorhabditis elegans (C. elegans) and their toxic effects were evaluated. Nanopolystyrene particles with sizes of 50 and 200 nm were prepared, and the L4 stage of C. elegans was exposed to these particles for 24 h. Their uptake was monitored by confocal microscopy, and various phenotypic alterations of the exposed nematode such as locomotion, reproduction and oxidative stress were measured. In addition, a metabolomics study was performed to determine the significantly affected metabolites in the exposed C. elegans group. Exposure to nanopolystyrene particles caused the perturbation of metabolites related to energy metabolism, such as TCA cycle intermediates, glucose and lactic acid. Nanopolystyrene also resulted in toxic effect including induction of oxidative stress and reduction of locomotion and reproduction. Collectively, these findings provide new insights into the toxic effects of nanopolystyrene particles.