Although it is proved that humans ingest microplastics via food, and microplastics were found in human tissues, blood and feces, there needs to be more data on the properties and health-related effects of plastic particles that interact with food and undergo digestion. This study aimed to examine the impact of a real food matrix, milk, on the behavior and gastrointestinal fate of polystyrene microparticles (PSMP). In the presence of the food matrix, the net negative ζ-potential values of PSMP (diameter size of 1.823 μm) decreased significantly due to the formation of the corona, mostly consisting of α and β-casein fragments. Protein corona profiles and morphologies of particles incubated with whole and skim milk were found to be similar, and the protein profiles were completely altered after in vitro digestion simulation. In vitro and in vivo toxicity studies showed that neither bare PSMP nor food-interacted PSMP pose acute toxicity on the Caco-2 cell line and zebrafish embryos under the chosen experimental conditions. In summary, these results may contribute to a better understanding of changes that microplastics undergo in foods. Further studies on repeated exposure or chronic toxicity are needed to fully reveal the effect of food matrix on microplastic toxicity.

尽管已证明人类通过食物摄入微塑料，并且在人体组织、血液和粪便中发现了微塑料，但仍需要更多关于与食物相互作用并消化的塑料颗粒的特性和与健康相关的影响的数据。本研究旨在研究真正的食物基质牛奶对聚苯乙烯微粒 (PSMP) 的行为和胃肠道命运的影响。在食物基质存在的情况下，PSMP（直径大小为 1.823 μm）的净负 z 电势值由于电晕的形成而显着下降，电晕主要由 α 和 β-酪蛋白片段组成。发现用全脂奶和脱脂奶孵育的颗粒的蛋白质电晕谱和形态相似，并且在体外消化模拟后蛋白质谱完全改变。体外和体内毒性研究表明，在选定的实验条件下，裸露的 PSMP 和与食物相互作用的 PSMP 都不会对 Caco-2 细胞系和斑马鱼胚胎产生急性毒性。总之，这些结果可能有助于更好地了解微塑料在食品中发生的变化。需要对重复接触或慢性毒性进行进一步研究，以充分揭示食物基质对微塑料毒性的影响。