The ubiquitous pollution of plastic particles in most environmental matrices leads to concern about any potential adverse effects on human health. Most studies on the toxicological effect of nanoplastics has focused on standard particles of polystyrene. In reality humans are exposed to a large variety of different types and sizes of plastic material via oral intake and inhalation. In this study, we investigated the effect of polyethylene terephthalate (PET) nanoplastic particles from ground food containers from a supermarket. The aim was to investigate a possible link between exposure to PET nanoplastics and genotoxic response in a cell model of the human airway epithelial (A549) cells. Further, we investigated the combined effect of PET and chemicals known to alter the cellular redox state, as a model of partially compromised antioxidant defense system. DNA damage was assessed by the alkaline comet assay. The ground PET nanoplastics have a mean hydrodynamic diameter of 136 nm in water. The results showed that PET exposure led to increased reactive oxygen species production (approximately 30 % increase compared to unexposed cells). In addition, exposure to PET nanoplastic increased the level of DNA strand breaks (net increase = 0.10 lesions/10⁶ base pair, 95 % confidence interval: 0.01, 0.18 lesions/10⁶ base pair). Pre- or post-exposure to hydrogen peroxide or buthionine sulfoximine did not lead to a higher level of DNA damage. Overall, the study shows that exposure to PET nanoplastics increases both intracellular reactive oxygen production and DNA damage in A549 cells.

大多数环境基质中普遍存在的塑料颗粒污染引发了人们对对人类健康潜在不利影响的担忧。大多数关于纳米塑料毒理学效应的研究都集中在聚苯乙烯标准颗粒上。事实上，人类通过口腔摄入和吸入接触到多种不同类型和尺寸的塑料材料。在这项研究中，我们研究了超市研磨食品容器中的聚对苯二甲酸乙二醇酯 (PET) 纳米塑料颗粒的影响。目的是在人类气道上皮 (A549) 细胞模型中研究 PET 纳米塑料暴露与基因毒性反应之间可能存在的联系。此外，我们研究了 PET 和已知可改变细胞氧化还原状态的化学物质的综合效应，作为部分受损的抗氧化防御系统的模型。DNA 损伤通过碱性彗星测定进行评估。研磨后的 PET 纳米塑料在水中的平均流体动力学直径为 136 nm。结果表明，暴露于 PET 会导致活性氧产生增加（与未暴露的细胞相比增加约 30%）。此外，暴露于PET纳米塑料增加了DNA链断裂的水平（净增加=0.10损伤/10 ⁶碱基对，95%置信区间：0.01、0.18损伤/10 ⁶碱基对）。暴露于过氧化氢或丁硫氨酸亚砜亚胺之前或之后不会导致更高水平的 DNA 损伤。总体而言，该研究表明，暴露于 PET 纳米塑料会增加 A549 细胞内活性氧的产生和 DNA 损伤。