Serum Perfluorooctanoate (PFOA) and Perfluorooctane Sulfonate (PFOS) Concentrations and Liver Function Biomarkers in a Population with Elevated PFOA Exposure

Abstract

Background: Perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) persist in the environment and are found in relatively high concentrations in animal livers. Studies in humans have reported inconsistent associations between PFOA and liver enzymes.Objectives: We examined the cross-sectional association between serum PFOA and PFOS concentrations with markers of liver function in adults.Methods: The C8 Health Project collected data on 69,030 persons; of these, a total of 47,092 adults were included in the present analysis. Linear regression models were fitted for natural log (ln)-transformed values of alanine transaminase (ALT), γ-glutamyltransferase (GGT), and direct bilirubin on PFOA, PFOS, and potential confounders. Logistic regression models were fitted comparing deciles of PFOA or PFOS in relation to high biomarker levels. A multilevel analysis comparing the evidence for association of PFOA with liver function at the individual level within water districts to that at the population level between water districts was also performed.Results: ln-PFOA and ln-PFOS were associated with ln-ALT in linear regression models [PFOA: coefficient, 0.022; 95% confidence interval (CI): 0.018, 0.025; PFOS: coefficient, 0.020; 95% CI: 0.014, 0.026] and with raised ALT in logistic regression models [with a steady increase in the odds ratio (OR) estimates across deciles of PFOA and PFOS; PFOA: OR = 1.10; 95% CI: 1.07, 1.13; PFOS: OR = 1.13; 95% CI: 1.07, 1.18]. There was less consistent evidence of an association of PFOA and GGT or bilirubin. The relationship with bilirubin appears to rise at low levels of PFOA and to fall again at higher levels.Conclusions: These results show a positive association between PFOA and PFOS concentrations and serum ALT level, a marker of hepatocellular damage.

Consumption of Seafood, Serum Liver Enzymes, and Blood Levels of PFOS and PFOA in the Japanese Population

“…Positive correlations of serum levels of PFOA with serum liver enzymes (γ -GTP, GOT or GPT) have been reported in several studies on fluorochemical workers with heavy exposure to PFOA or its related substance 32,33) but not in others 34,35) . Positive correlations were also observed between serum levels of PFOA or PFOS and hepatic enzymes (γ -GTP and/or GPT) in populations of the U.S. with high or background exposure to these PFCs 36,37) . One explanation for the positive associations found in the present study may be that liver cell damage alters the rate of elimination of PFOS and PFOA from the human body.…”

Perfluoroalkyl acids (PFAAs) with isomer analysis in the commercial PFOS and PFOA products in China

“…After decades of industrial production and application, PFAAs have been ubiquitous in water, soil, wildlife and humans all over the world (Houde et al, 2006). The most frequently detected PFAAs in the environment are perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), and they may pose potential health risks on humans (Lopez-Espinosa et al, 2011;Shankar et al, 2011;Gallo et al, 2012;Grandjean et al, 2012). Due to the hazardous effects of these chemicals and additional concerns about their persistence in the environment and potential accumulation in food webs, PFOS and its precursors were listed as Annex B persistent organic pollutant under the International Stockholm Convention Treaty in 2009 .…”

Synergistic effects of perfluoroalkyl acids mixtures with J-shaped concentration–responses on viability of a human liver cell line

“…Although these studies suggest that the peroxisome proliferators activated receptor a (PPARa)-dependent mode of action proposed for hepatic tumor induction in rodents is not relevant to humans (Bjork and Wallace, 2009), recent epidemiological data found significant positive associations between PFOA and PFOS concentrations and all lipid outcomes (except high density lipoprotein-cholesterol), with a relatively lower serum level of PFOA (median, 27 ng/mL) and PFOS (median, 20 ng/mL) in 46,294 community residents from a West Virginian chemical plant (C8 Health Project) (Steenland et al, 2009). In addition, researchers have found a linear association between PFOA/PFOS serum concentrations and alanine transferase (a marker of hepatocellular injury) (Gallo et al, 2012). Thus, the ubiquitous presence and persistence of PFAAs in the environment and within the human body have led to efforts to understand adverse effects that may be associated with exposure, in particular scientific and regulatory concerns.…”