Extractable Organofluorine Analysis in Pooled Human Serum and Placental Tissue Samples from an Austrian Subpopulation-A Mass Balance Analysis Approach.

Andreas-Marius Kaiser,Martin Forsthuber,Christina Hartmann,Maria Uhl,Anna Kärrman,Harald Zeisler,Claudia Gundacker,Rudolf Aro,Leo W Y Yeung,Philipp Foessleitner,Hans Salzer

doi:10.1021/acs.est.1c00883

Abstract

Embryos and fetuses are of major concern due to their high vulnerability. Previous studies demonstrated that human exposure to per- and polyfluoroalkyl substances (PFAS) may be underestimated because only a limited number of known PFAS can be measured. This investigation studied the total PFAS exposure by measuring the extractable organofluorine (EOF) in pooled maternal serum, placental tissue, and cord serum samples (total number of pooled samples: n = 45). The EOF was analyzed using combustion ion chromatography, and the concentrations of known PFAS were determined using ultraperformance liquid chromatography coupled with a tandem mass spectrometer. Using a mass balance analysis approach, the amount of unknown PFAS was estimated between the levels of known PFAS and EOF. The EOF levels ranged from 2.85 to 7.17 ng F/mL (21 PFAS were quantified) in the maternal serum, from 1.02 to 1.85 ng F/g (23 PFAS were quantified) in the placental tissue, and from 1.2 to 2.10 ng F/mL (18 PFAS were quantified) in the cord serum. An average of 24, 51, and 9% of EOF is unidentified in the maternal serum, placental tissue, and cord serum, respectively. The results show that the levels of unidentified EOF are higher in the placental tissue, suggesting accumulation or potential transformation of precursors in the placenta.

Highlights

Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals that have been widely used for numerous industrial and commercial applications since the 1950s because of their unique chemical and physical properties, which include being hydrophobic, lipophobic, and extremely stable even at high temperatures.[1−4] These chemicals have globally been detected in all environmental media, including biota as well as in humans.[5]
In addition to displaying persistent and bioaccumulative properties, some PFAS are suspected to cause multiple adverse health effects, for example, carcinogenicity, immunotoxicity, neurotoxicity, low birth weight in newborns, delayed puberty, and low semen quality in young men.[5−10] The European Food Safety Authority recently set out a lower tolerable weekly intake of 4.4 ng/kg body weight based on the sum of four PFAS [perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS)] due to their adverse effects on the immune system.[11]
Novel PFAS, which have emerged as alternatives to legacy perfluoroalkyl acid (PFAA) (e.g., PFOA and PFOS), such as per- and polyfluoroalkyl ethers [e.g., dodecalfluoro-3H-4,8-dioxanonanoate (ADONA)], were recently detected in human cord serum as well.[15,18,19]

Summary

Introduction

Per- and polyfluoroalkyl substances (PFAS) are a group of synthetic chemicals that have been widely used for numerous industrial and commercial applications since the 1950s because of their unique chemical and physical properties, which include being hydrophobic, lipophobic, and extremely stable even at high temperatures.[1−4] These chemicals have globally been detected in all environmental media, including biota as well as in humans.[5] In addition to displaying persistent and bioaccumulative properties, some PFAS are suspected to cause multiple adverse health effects, for example, carcinogenicity, immunotoxicity, neurotoxicity, low birth weight in newborns, delayed puberty, and low semen quality in young men.[5−10] The European Food Safety Authority recently set out a lower tolerable weekly intake of 4.4 ng/kg body weight based on the sum of four PFAS [perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS)] due to their adverse effects on the immune system.[11] Several studies have reported perfluoroalkyl acid (PFAA) levels in human cord serum,[12−14] human placental tissue,[15,16] and some even in the human embryonic and fetal tissue.[17] Novel PFAS, which have emerged as alternatives to legacy PFAAs (e.g., PFOA and PFOS), such as per- and polyfluoroalkyl ethers [e.g., dodecalfluoro-3H-4,8-dioxanonanoate (ADONA)], were recently detected in human cord serum as well.[15,18,19]. Information on PFAS levels in the Received: February 6, 2021 Revised: June 7, 2021 Accepted: June 8, 2021 Published: June 16, 2021

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