Ovarian Cell Accumulation of Model <scp>PVC</scp> Nanoplastics Labelled With <scp>CdSe</scp> ‐ <scp>QDs</scp> Investigated by X‐Ray Fluorescence Microscopy

ABSTRACT The distribution of micro‐ and nanoplastics (MNPs) in the environment is increasingly becoming a cause of concern for human health. The small size of these particles makes them prone to accumulate not only in the tissues of various organs but also enables them to enter cells and act as carriers of external materials and microbes. Since environmental pollutants influence both male and female reproductive function and foetal development, it is expected that this also applies to MNPs, as they can easily accumulate in reproductive organs. This highlights the potential risks associated with MNPs and the need for further research in this area. In the female reproductive system, the ovary plays a crucial role in producing oocytes. The SK‐OV‐3 human ovarian cancer cell line represents an epithelial‐like model for ovarian cells, and it has been widely used in nanomedicine and nanotoxicological studies. In the present study, x‐ray fluorescence (XRF) microscopy was used to investigate the accumulations of model polyvinyl chloride (PVC) nanoplastics (NPs), labelled with cadmium‐selenide quantum dots (CdSe‐QDs), in SK‐OV‐3 cells at sub‐micrometric spatial resolution. The Cd and Se QDs components distribution and the Cl of PVC were successfully used to track the NPs and to confirm that NPs do not leach the QDs, while endogenous elements such as Na, Mg, S and P were also monitored to investigate potential biochemical changes attributed to NPs toxicity. Our study suggests that nanoplastics made of PVC can accumulate in ovarian cells, even if they appear less incline than in other types of cells, such as macrophages. Moreover, our results demonstrate that XRF analyses are a useful tool for biological studies aimed at deepening our understanding on the toxicological mechanisms of pollutants on human fertility.