Effects of perfluorooctane sulfonate (PFOS) exposure on markers of inflammation in female B6C3F1 mice

Perfluorooctane sulfonate (PFOS; 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-heptadecafluoro-1-octanesulfonic acid) has been reported to alter humoral immune functions, but inflammatory processes following PFOS exposure have not been fully characterized. Therefore, the current study, assessed TNF-α and IL-6 concentrations in serum and peritoneal lavage fluid, numbers of splenoctyes expressing intracellular TNF-α, IL-6, IL-10 or IL-1, and ex vivo TNF-α and IL-6 production by peritoneal macrophages following either in vivo or in vitro LPS exposure. Adult female B6C3F1 mice were exposed orally for 28 days to 0, 1, 3, or 300 mg PFOS/kg total administered dose [TAD] (e.g., 0, 0.0331, 0.0993 or 9.93 mg/kg/day). Body and spleen masses were significantly reduced in the highest PFOS treatment group compared to the control group, whereas liver mass was significantly increased. Serum TNF-α levels were significantly decreased following exposure to 1 mg PFOS/kg TAD as compared to controls, while serum IL-6 levels were increased. IL-6 concentrations in peritoneal lavage fluid decreased with increasing dose. PFOS treatment did not alter numbers of splenocytes expressing intracellular levels of TNF-α, IL-10 or IL-1. Numbers of splenocytes expressing intracellular levels of IL-6 were significantly decreased in the 3 mg/kg treatment as compared to controls. Overall, these data suggest that PFOS exposure can alter some inflammatory processes, which could potentially lead to misdirected inflammatory responses.