title: Extraction of perfluorinated alkyl acids from human serum for determination of the combined xenoestrogenic transactivity: a method development.
abstract: Humans are exposed to perfluorinated alkyl acids (PFAAs) through food, drinking water, consumer products, dust, etc. The human metabolism and excretion of the long-chain PFAAs is slow with half-lives up to 8.8years. Studies suggest that the PFAAs are potential endocrine-disrupting compounds that might affect human health. We developed a method for extraction of PFAAs from human serum with simultaneous removal of endogenous sex hormones. The developed method includes solid phase extraction, liquid/liquid extraction, HPLC fractionation and weak anion exchange. The method was validated by extraction of seven persistent PFAAs spiked to human male serum obtaining mean recoveries between 49.6% and 78.6%. Using an estrogen receptor (ER) transactivation luciferase reporter gene assay, analysis of the extracted PFAA serum fraction from three pregnant women showed the ER-active endogenous hormones were removed. The developed method was further documented by extraction of the PFAAs from the serum of 18 Danish pregnant women. The PFAA fraction from three of the 18 samples significantly induced the ER-transactivity. Upon co-exposure with the natural ER-ligand 17β-estradiol (E2), 17 of the 18 PFAA fractions caused a significant further increase of the E2 induced ER-transactivity. In conclusion, we developed a method to extract PFAAs from human serum, and the method documentation suggested that PFAAs at the levels found in human serum can transactivate the ER.
authors.affiliation: Centre for Arctic Health & Unit of Cellular and Molecular Toxicology, Department of Public Health, Aarhus University, Bartholins Allé 2, Build. 1260, DK-8000 Aarhus C, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Bjerregaard-Olesen
authors.affiliation: Department of Environmental Science, Aarhus University, Frederiksborgvej 399, DK-4000 Roskilde, Denmark.
authors.forename: Rossana
authors.initials: R
authors.lastname: Bossi
authors.affiliation: Section for Epidemiology, Department of Public Health, Aarhus University, Bartholins Allé 2, Build. 1260, DK-8000 Aarhus C, Denmark.
authors.forename: Bodil Hammer
authors.initials: BH
authors.lastname: Bech
authors.affiliation: Centre for Arctic Health & Unit of Cellular and Molecular Toxicology, Department of Public Health, Aarhus University, Bartholins Allé 2, Build. 1260, DK-8000 Aarhus C, Denmark. Electronic address: ebj@mil.au.dk.
authors.forename: Eva Cecilie
authors.initials: EC
authors.lastname: Bonefeld-Jørgensen
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D052244:Endocrine Disruptors; D005260:Female; D005466:Fluorocarbons / Q000097:blood*; D006801:Humans; D008297:Male; D011247:Pregnancy; D011960:Receptors, Estrogen / Q000378:metabolism*; D052616:Solid Phase Extraction / Q000379:methods
chemical_list: D052244:Endocrine Disruptors; D005466:Fluorocarbons; D011960:Receptors, Estrogen
keywords: Estrogen receptor; Perfluorinated compounds; Preparative normal phase HPLC; Solid Phase Extraction; Weak anion exchange; Xenoestrogenicity