Associations between lipid/lipoprotein levels and perfluoroalkyl substances among US children aged 6-11 years.

Observed levels of lipid/lipoproteins are known to be associated with exposure to perfluoroalkyl substances (PFAS). In order to evaluate and update these associations among US children aged 6-11 years, data (N = 458) from National Health and Nutrition Examination Survey for 2013-2014 were used. The associations between the observed levels of total cholesterol, high density lipoprotein (HDL) cholesterol, and non-HDL cholesterol and selected PFAS were studied. PFAS data were available for perfluorononanoic acid (PFNA), perfluorohexane sulfonate (PFHxS), linear isomer of perfluorooctanoic acid (PFOA), linear isomer of perfluorooctane sulfonate (PFOS), monomethyl branch isomer of PFOS, and sum of PFAS. Regression models were fitted to evaluate these associations. A statistically significant (p = 0.03) positive association between the levels of linear isomer of PFOS and total cholesterol was observed. A 10% increase in the levels of linear isomer of PFOS measured in ng/L was found to be accompanied by a 0.03-0.42% increase in the levels of total cholesterol measured in mg/dL. For PFNA, girls in the first quartile of PFNA were found to have lower adjusted levels for total cholesterol than the girls in the fourth quartile of PFNA (152.6 vs. 164.7 mg/dL, p < 0.01). Also, non-Hispanic blacks in the first quartile of PFNA were found to have lower adjusted levels for total cholesterol than the non-Hispanic blacks in the fourth quartile of PFNA (143.4 vs. 160.5 mg/dL, p = 0.04). A negative association between branch isomer of PFOS and non-HDL cholesterol was also observed (β = -0.0066, p = 0.04). The adjusted levels of non-HDL cholesterol were higher in the second quartile of ∑PFAS than in the fourth quartile of ∑PFAS (103.0 vs. 97.5 mg/dL, p < 0.01). Linear PFOS and possibly PFNA are associated with total cholesterol in the most recent NHANES childhood sample. Concentrations of PFAS and associations with cholesterol have both decreased compared to previous literature.