Untargeted high-resolution metabolomics to measure and describe the “perfluorome”

Abstract

OPS 59: The Exposome: progress in methods and applications, Room 412, Floor 4, August 28, 2019, 1:30 PM - 3:00 PM Background/Aim: Poly- and perfluorinated alkyl substances (PFAS) are used in industrial processes and consumer products. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), two PFAS, have been phased out of use in the United States because of their biological and environmental persistence, widespread detection in human sera, and concern over adverse health effects. However, other PFAS have not been well studied. Thus, we aimed to describe exposure to a suite of PFAS – the perfluorome – in order to characterize profiles of exposure to a broad range of PFAS. Methods: We quantified serum concentrations of six PFAS with targeted methods, and conducted untargeted high-resolution metabolomics profiling of serum from 114 8-year old children from Cincinnati, Ohio. We performed Principal Component Analysis (PCA) to characterize serum PFAS profiles. Results: We annotated 178 PFAS measured by untargeted methods and categorized 137 them into families based on their chemical structures. The first three principle components (PC) explained 20% of the variation of these 137 PFAS. Fluorotelomer-related compounds loaded strongly on the first three PCs. Perfluoroalkyl carbonyls, including PFOA, also loaded strongly on PC2. PFOS loaded strongly on PC5, in addition to perfluorohexane sulfonic acid (PFHxS), and perfluorodecanoic acid (PFDA). Notably, correlations between targeted and untargeted methods were strong (r ≥ 0.9), except for PFOA (r = 0.45) and perfluorononanoic acid (PFNA; r = 0.24). Conclusions: In this cohort, we tentatively identified 178 different PFAS in 8-year old children’s serum. Two families of PFAS (fluorotelomer-related compounds and perfluoroalkyl carbonyls), representing exposure to chemicals used in surfactant and surface protection products and their production, were important in explaining the variance of the perfluorome. Future studies should evaluate the potential health risks associated with exposure to these other PFAS.