Molecular and metabolic profiles of individual and combined nanoplastic–BPA exposure assessed by FTIR spectroscopy

The excessive use of plastic has raised concerns about exposure to nanoplastics (NPs) and bisphenol A (BPA) and their impacts on human health. This study aimed to assess a new method of detecting the in vitro effects of NPs and BPA that is sensitive yet simpler and faster compared to cytogenetic techniques such as cytokinesis-blocked micronucleus (CBMN) assay.

Individual and combined exposure of BPA and polystyrene nanoparticles (PS-NPs) was evaluated using the GP202 gastric cell line. The culture media, designated as 0h after exposure and 24h after the exposure, and cells 24h after exposure, were analyzed by Fourier transform infrared (FTIR) spectroscopy. CBMN did not reveal statistically significant differences in exposure to NPs and BPA compared with controls, though a trend towards an increase in MN, nucleoplasmic bridges (NBPs), and nuclear buds (NBUDs) was observed with combined exposure to PS-NPs and BPA. A univariate analysis of several FTIR spectral bands was performed after various spectral preprocessing methods, including baseline correction, baseline correction with normalization, second derivative, and second derivative with normalization. Several statistically different bands were observed, with significance at 1%, 5%, and 10%, both in multiple comparisons between exposure conditions and pairwise comparisons between exposure conditions. These changes were noted in spectra obtained from culture media and directly from cells. The FTIR spectrum represents the molecular profile of the culture media and cells, reflecting the metabolic state of the cells. Thus, FTIR spectroscopy proves to be a highly sensitive, rapid, and straightforward technique for detecting metabolic changes in gastric cell lines when exposed to NPs and BPA, even in conditions where no genotoxic changes are detected, as observed by CBMN.