Polyethylene terephthalate (PET) nanoparticles and the physiological effect on intestinal tissue contraction. Ex-vivo approaches

Microplastic ubiquity has been demonstrated in several studies. They are polluting the environment, as well as food and water for human consumption, where the most significant concern has arisen over the ingestion of microplastics. However, there are very few studies on the potential health risks associated with nanoparticles, including those related to polyethylene terephthalate (PET). In this work, PET nanoparticles (253 ± 16 d nm) with irregular shape obtained under controlled conditions, were used for ex vivo analysis of rat intestinal tissue (n = 3 each condition) and their effects on the muscle tone related to peristalsis were determined. Twenty-minute treatment with increasing concentrations of PET-NPs from 0.1 to 100 μg/mL (low concentrations) and from 250 to 750 μg/mL (high concentrations) were assayed. The results showed the rapid capability of PET nanoparticles to cross the intestinal barrier, assessed by fluorescence microscopy and corroborated by RAMAN micro-spectroscopy. Furthermore physiological analysis in isolated rat intestinal segments have demonstrated the effects of PET, especially at 10 μg/mL, on tissue contraction. These results evidenced the potential health risk related to nano-plastic ingestion, due to PET nanoparticles tissue accumulation and the effects on contraction and relaxation tissue functions.