Per-/polyfluoroalkyl substance concentrations in human serum and their associations with liver cancer.

Per-/polyfluoroalkyl substances (PFASs) are widespread in global human blood, and have some toxic effects on liver. However, effects of PFAS exposure on human liver cancer (LC) risk are still not known. In this study, 203 LC patients and 203 controls were recruited, and their serum samples were collected between 2019 and 2021. We determined the residues of 12 PFASs in serum from all participants and quantified their association with LC incidence and tumor markers. PFOS (9.8 ng/mL) had the highest mean concentration in human serum, followed by PFOA (8.3 ng/mL) and 6:2 Cl-PFESA (3.9 ng/mL). We found that concentrations of PFOS and 6:2 Cl-PFESA in human serum were significantly correlated with the levels of alpha fetoprotein (AFP) (βPFOS = 0.13, 95% confidence interval (CIPFOS): 0.088, 0.17; β6:2 Cl-PFESA = 0.070, CI6:2 Cl-PFESA: 0.036, 0.10). A positive association of PFOS and 6:2 Cl-PFESA with odds ratios (OR) of LC (ORPFOS = 0.609, CIPFOS: 1.179, 4.029, P = 0.001; OR6:2 Cl-PFESA = 1.844, CI6:2 Cl-PFESA: 1.176, 2.512, P = 0.02) were found, after adjusting for different covariates. Moreover, serum PFOA concentrations were associated with carcinoembryonic antigen (CEA), but their correlation with the LC incidence was not statistically significant. This new finding supports the evidence for the positive associations among PFAS exposure, change of specific tumor marker, and LC risks.