Early-life associations between per- and polyfluoroalkyl substances and serum lipids in a longitudinal birth cohort

Background: Exposures to perand polyfluoroalkyl substances (PFASs) may affect metabolic outcomes, including lipid concentrations in the blood. However, few studies have evaluated potential associations between PFASs and lipids longitudinally. Objectives: We estimated associations between PFAS and lipid concentrations at birth and at several points in childhood. Methods: We measured concentrations of five major PFASs in cord serum and in serum collected at 18 months, five years and nine years in 490 children from a prospective cohort in the Faroe Islands. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG) concentrations were measured at birth, 18 months and nine years. We estimated associations between PFAS and lipid concentrations and evaluated possible effect modification by sex. We also tested whether PFAS associations with age-nine lipids varied by exposure period. Results: Serum PFAS concentrations at ages five and nine were positively associated with lipid concentrations at age nine. Cross-sectional associations between PFASs and lipids at age nine were the strongest, with increases in serum concentrations of perfluorodecanoic acid (PFDA), perfluorononanoic acid (PFNA) and perfluorooctanesulfonic acid (PFOS) associated with increases in TC, HDL-C and LDL-C. We found statistically significant differences in estimated PFAS effects by sex, where girls had stronger positive associations between PFASs and TC and LDL-C and boys had stronger positive associations with HDL-C. In repeated measure models, exposure period was a significant modifier of PFAS effects. Conclusions: Our findings suggest that childhood PFAS exposures may be associated with elevated serum lipid concentrations. This is a public health concern, as a detrimental lipid profile in childhood is a risk factor for later development of hyperlipidemia and cardiovascular disease.