Selective Associations of Recent Low Concentrations of Perfluoroalkyl Substances With Liver Function Biomarkers NHANES 2011 to 2014 Data on US Adults Aged >= 20 Years

Objective: Perfluoroalkyl substances (PFAS) and liver function biomarkers were reexamined for relatively lower serum concentrations of PFAS observed in recent years. Methods: National Health and Nutrition Examination Survey 2011 to 2014 data were analyzed for obese and nonobese participants for serum perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (PFDA), perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA) as well as four liver function biomarkers in risk-adjusted analysis. Results: Among obese participants only, alanine aminotransferase (ALT) was positively associated with PFOA (beta = 0.07065, P < 0.01), PFHxS (beta = 0.051349, P < 0.01), and with PFNA (beta = 0.072742, P < 0.01). PFOA (beta = 0.07422, P = 0.03) and PFNA (beta = 0.077995, P < 0.01) were associated with gamma glutamyl transferase (GGT) in obese participants. Conclusions: Recent lower levels of PFOA, PFHxS, and PFNA are associated with higher serum liver functions but only among obese participants. The findings are consistent with PFAS animal toxicology concerning steatosis.