Per- and polyfluoroalkyl substances and fluorinated alternatives in urine and serum by on-line solid phase extraction–liquid chromatography–tandem mass spectrometry

Abstract

Per- and polyfluoroalkyl substances (PFAS), man-made chemicals with variable length carbon chains containing the perfluoroalkyl moiety (CF-), are used in many commercial applications. Since 1999-2000, several long-chain PFAS, including perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), have been detected at trace levels in the blood of most participants of the National Health and Nutrition Examination Survey (NHANES)-representative samples of the U.S. general population-while short-chain PFAS have not. Lower detection frequencies and concentration ranges may reflect lower exposure to short-chain PFAS than to PFOS or PFOA or that, in humans, short-chain PFAS efficiently eliminate in urine. We developed on-line solid phase extraction-HPLC-isotope dilution-MS/MS methods for the quantification in 50 μL of urine or serum of 15 C-C PFAS (C only in urine), and three fluorinated alternatives used as PFOA or PFOS replacements: GenX (ammonium salt of 2,3,3,3,-tetrafluoro-2-(1,1,2,2,3,3,3-heptafluoropropoxy)-propanoate, also known as HFPO-DA), ADONA (ammonium salt of 4,8-dioxa-3H-perfluorononanoate), and 9Cl-PF3ONS (9-chlorohexadecafluoro-3-oxanonane-1-sulfonate), main component of F53-B. Limit of detection for all analytes was 0.1 ng/mL. To validate the method, we analyzed 50 commercial urine/serum paired samples collected in 2016 from U.S. volunteers with no known exposure to the chemicals. In serum, detection frequency and concentration patterns agreed well with those from NHANES. By contrast, except for perfluorobutanoate, we did not detect long-chain or short-chain PFAS in urine. Also, we did not detect fluorinated alternatives in either urine or serum. Together, these results suggest limited exposure to both short-chain PFAS and select fluorinated alternatives in this convenience population.

Outcome of a public consultation on the draft risk assessment of perfluoroalkyl substances in food

“…The CONTAM Panel agrees to include the study by Kato et al (2018), and this has now been done. In this subchapter, a recent publication about PFAS serum levels in the Veneto Region, Italy has not been cited: Ingelido et al (2018).…”

Liquid-Chromatographic Methods for Carboxylic Acids in Biological Samples

“…Maestri et al analyzed perfluorooctanoic acid using a C18 disposable SPE cartridge [50]. Oasis WAX cartridges, wherein extraction is conducted in a mixed mode of RP and weak anion exchange, have likewise been used [51,52]. Prior to SPE operation, a mixture of HCl and HNO 3 was added to eliminate the matrix, in the case of bivalve samples, leading to improved recoveries (92-104%) and selectivity.…”

Analysis of hexafluoropropylene oxide-dimer acid (HFPO-DA) by liquid chromatography-mass spectrometry (LC-MS): Review of current approaches and environmental levels

“…In these cases, the additional MRM is used for analyte confirmation, as explicitly stated by Gebbink et al [54]. Generally, the recently introduced stable isotope labeled (SIL) standard for HFPO-DA ( 13 C 3 -HFPO-DA) was also included in the MRM schedule and used in isotope dilution quantification [6,8,54,57,60], or for recovery assessment in sample matrices [section 2.3]. Specific use of 13 C 3 -HFPO-DA in two studies from the same group was not stated, but the SIL was added prior to extraction and was likely used to correct for losses during extraction.…”

“…The establishment of limits-of-detection and quantification (LOD and LOQ) in several studies rely on signal-to-noise (S/N) values of 3 and 10 respectively, or an extrapolation thereof [8,14,[54][55][56][57][58]60]. Comparison of the instrument and method sensitivity values reported for other PFAS can be used to deduce HFPO-DA response in existing methods, described in Table 2.…”

“…However, the first study to report environmental detection of GenX/HFPO-DA, using typical LC methodology employed for legacy PFAS coupled with non-targeted MS acquisition, observed ionisation behaviour which yielded very little of the desired [M−H] − species [2,53]. Although the ionization conditions used presently require improvement, increasing interest in HFPO-DA has resulted in the incorporation of the compound in existing targeted PFAS analyses [3,8,14,[54][55][56][57][58][59][60], along with another PFECA, dodecafluoro-3H-4,8dioxanonanoate (ADONA) [55][56][57]60]. In late 2018, HFPO-DA was added to the United States Environmental Protection Agency (US EPA) Method 537.1 list of 18 PFAS to be determined in drinking water [61].…”