Concurrent Assessment of Micro- and Nanoplastics and Bisphenol A in Non-Dialysis Chronic Kidney Patients and Hemodialysis Patients: Results from a Cross-Sectional Human Biomonitoring Study Focusing on Sex-Related Patterns

Patients with chronic kidney disease (CKD), particularly those receiving hemodialysis (HD), may be more vulnerable to exposure to micro- and nanoplastics (MNPs) and bisphenol A (BPA) because of impaired renal clearance and frequent contact to plastic-based medical devices. This study aimed to assess and compare the levels of blood MNPs and urinary BPA in HD patients, non-dialysis CKD patients, and healthy subjects with a focus on sex-related differences and the potential role of hemodialysis as an additional source of exposure. A cross-sectional human biomonitoring study was conducted. Blood and urine samples were collected to quantify BPA using gas chromatography–mass spectrometry (GC–MS) and MNPs using scanning electron microscopy coupled with an Energy-Dispersive X-ray Detector (SEM-EDX). Descriptive statistics included medians, interquartile ranges (IQRs), 95% confidence intervals, frequencies, and percentages. Blood MNP levels were higher in HD [9889 (4525–14,939) p/mL] and non-dialysis CKD patients [9234 (3354–15,429) p/mL] than in healthy subjects [5755 (2488–9042) p/mL]. Urinary MNP levels were also higher in non-dialysis CKD patients [1231 (0–8281) p/mL] than in healthy subjects [411 (0–1636) p/mL]. Urinary MNPs were smaller in non-dialysis CKD patients than in healthy subjects. In contrast, urinary BPA levels were lower in non-dialysis CKD patients [0.16 (0.12–0.16)] than in healthy subjects [0.98 (0.60–2.36)]. Sex-specific patterns were observed. Females had higher blood MNP levels than males among HD patients (median 9907 vs. 9063 p/mL) and healthy subjects (6627 vs. 4131 p/mL), whereas the opposite pattern was observed in non-dialysis CKD patients (10,083 vs. 7340 p/mL). Overall, these findings suggest an increased systemic burden of MNPs and altered BPA elimination in non-dialysis CKD and HD patients. The observed sex-specific patterns suggest that biological sex may contribute to differences in internal exposure within this vulnerable population.