Intrinsic Peroxidase-like Activity of Polystyrene Nanoplastics Mediates Oxidative Stress

• DOI: 10.1021/acs.est.4c04487
• Publication Date: 2024-08-22T21:52:05Z
• Authors: Yi Tan; Siyue Chen; Mengjiao Wang; Heyun Fu; Pedro J. J. Alvarez; Xiaolei Qu
• Keywords: Polystyrene; Enzyme Kinetics

Nanoplastics represent a global environmental concern due to their ubiquitous presence and potential adverse impacts on public health. There is growing need advance the mechanistic understanding of reactivity as they interact with biological systems. Herein, for first time, we report that polystyrene nanoplastics (PSNPs) have intrinsic peroxidase-like activity are able mediate oxidative stress. The dependent temperature pH, maximum at pH 4.5 40 °C. catalytic exhibits saturation kinetics, described by Michaelis–Menten model. PSNPs attributed ability electron transfer from peroxidase substrates H2O2. Ozone-induced PSNP aging can introduce oxygen-containing groups disrupt aromatic structures nanoplastic surface. While ozonation initially enhances increasing without degrading many structures, extended destroys significantly reducing this activity. stress, which generally positively correlated suggested ascorbic acid assay. These results help explain reported stress exerted provide novel insights into health implications.