Pilot Study on Human Exposure to Microplastics in Intraocular Fluids and Bisphenols in Serum: Analytical Detection and Characterisation

The widespread presence of microplastics (MPs) and associated plastic-derived compounds, bisphenols (BPs), in the environment—originating from plastic production or adsorption of environmental pollutants—results in unavoidable human exposure. Therefore, assessing their occurrence in human biological samples is essential for understanding potential health risks. In this study, pyrolysis gas chromatography–mass spectrometry was used to analyse human intraocular fluids—aqueous humour (AH) and vitreous humour (VH)—to identify 11 microplastic polymer clusters. A method based on dansyl chloride derivatisation combined with ultra-performance liquid chromatography–tandem mass spectrometry was employed to screen for five bisphenols (BPs) in blood serum collected from the same patients. Potential MPs isolated from ocular samples were qualitatively assessed by stereomicroscopy. The number of particles ranged from 14 to 69 per gram in AH and from 21 to 34 per gram in VH. Among AH samples, the most frequently detected polymer clusters were C-PVC, C-PMMA, C-PET, and C-PP, with average levels ranging from 0.41 to 0.84 µg/g. The three VH samples contained only C-PMMA, with an average concentration of 0.55 ± 0.12 µg/g. Polymers such as C-PA66 (0.30 ± 0.21 µg/g) and C-PA6 (0.15 ± 0.44 µg/g) were occasionally observed in AH. Analysis of 13 human serum samples demonstrated exposure to bisphenol A (BPA; 4.05–5.18 ng/mL) and bisphenol AF (BPAF; 2.13–4.54 ng/mL), but no clear correlation was observed between serum BP levels and intraocular MPs within the limitations of the present dataset. These findings suggest the presence of MPs and BPs in human biological samples; however, the results should be interpreted with caution owing to potential background contamination and the pilot nature of the study.