Trace-level detection and quantification of PFAS

An ultra-high sensitivity analysis of PFAS compounds in multiple water sources

In this method sub-parts per trillion (ppt) levels of detection for 26 PFAS compounds was achieved with LOD values of 0.2 ng/L in diluent and calculated method detection limits in drinking, ground, and surface water ranging between 0.06 ng/L and 1.12 ng/L.

Achieving low parts-per-quadrillion detection limits for PFAS analysis in drinking water

A collaborative exploration of instrument sensitivity and sample preparation for ultra-trace analysis of PFAS on the SCIEX 7500 system.

An ultra-high sensitivity analysis of PFAS compounds in multiple water sources

In this method sub-parts per trillion (ppt) levels of detection for 26 PFAS compounds was achieved with LOD values of 0.2 ng/L in diluent and calculated method detection limits in drinking, ground, and surface water ranging between 0.06 ng/L and 1.12 ng/L

Screening for legacy and novel PFASs using SCIEX Fluoros Library 2.0

Currently there are more than 3000 Per- and Poly- fluorinated substance (PFAS) products that were or are available on the global market. Changing regulations and concern for human environmental impact make detection and identification of PFAS a high priority for many environmental testing laboratories. Many of these products may be not well understood or well characterized, and analytical grade standards are often unavailable, limiting the comprehensibility of targeted methods. Therefore, many laboratories have included suspect screening workflows in their routine analysis. Suspect screening allows laboratories to search against a spectral library or database of characterized compounds without the need of authentic standards, saving time and allowing for a more comprehensive characterization of environmental samples.

Quantitation of PFASs in water samples using LC-MS/MS large-volume direct injection and solid phase extraction

This technical note describes two methods for the quantitation of per- and polyfluorinated alkyl substances (PFASs) in water samples. Both methods achieved accurate quantitation at levels of approximately 1-10 ng/L for more than 17 PFASs. Method 1 is compatibility with EPA Method 537.

Simple and rapid quantification of per- and polyfluoroalkyl substances (PFAS) in seawater

In this technical note, a method is presented for quantifying per-and polyfluoroalkyl compounds (PFAS) in seawater at the low ng/L range using a simple sample preparation approach, with no solid phase extraction (SPE). The sensitivity of the SCIEX 7500 system1 allowed for the ultra-trace level quantification of PFAS in un-spiked seawater samples using only direct injection analysis

Achieving low parts-per-quadrillion detection limits for PFAS analysis in drinking water

This collaborative technical note demonstrated the ability to meet the ultra-trace levels of detection required for the 2022 EPA drinking water health advisory levels for PFAS. Future experiments will include an MDL study at the 4 and 20 ppq (pg/L) spiking levels for PFOA and PFOS, respectively.

Finding PFAS in people

PFAS quantification at trace levels (parts per trillion) can routinely be achieved by sensitivity triple quad mass spectrometers. PFAS, PFOA, PFOS, GenX, etc can be detected and measured with high precision. A large proportion of PFAS ‘unknowns’ exist in human serum however, and required advanced accurate mass workflows with QTOFs to identify the unknowns. Targeted serum analysis coupled with high resolution MRM quantification and non-targeted acquisition with suspect screening enables compound identification as well as fragmentation specificity. Watch this video series to discover how you can Find PFAS in People

PFAS in me

Bioaccumulation of PFAS in the human body resulting from environmental exposure is a growing public health concern. Recent studies have linked PFAS exposure to adverse health outcomes, including childhood health complications, reduction in kidney functions, thyroid disease, hormone suppression, decreased fertility, increased cholesterol levels, and diabetes, among others.

Rapid LC-MS/MS method for monitoring bio-relevant levels of per-and polyfluoroalkyl substances (PFAS) in serum

Here, a comprehensive workflow using the SCIEX QTRAP 6500+ System for the analysis of 22 PFASs in serum is presented. This targeted screening workflow is shown to provide a fast, robust and sensitive analytical method capable of accurately quantifying sub-nanogram per mL levels of PFASs in human serum. Here, a comprehensive workflow using the SCIEX QTRAP 6500+ System for the analysis of 22 PFASs in serum is presented. This targeted screening workflow is shown to provide a fast, robust and sensitive analytical method capable of accurately quantifying sub-nanogram per mL levels of PFASs in human serum.

Confident quantification of per- and polyfluoroalkyl substances in water intended for human consumption

An accurate and robust LC-MRM method using a smaller volume direct injection approach has been developed on the QTRAP 6500+ system, with sensitivity demonstrated to easily meet the current recommended limits set by the European authorities for drinking water (February 2020). Several PFAS specific analytical challenges have been addressed with this method, ensuring the method is easily implemented into labs. Data was also generated on the SCIEX 7500 system to highlight the advantages of increased sensitivity.

Identification and quantification of PFAS in food contact materials using MRMHR Workflow on X500R QTOF System

PFAS are widely used in plastic packaging materials for food and as coating in non-stick pans. MRMHR quantification enables detection and quantification of PFAS to meet EU regulation, national standards in China.

Analysis of hexafluoropropylene oxide dimer acid (HFPO-DA), commonly known as Gen-X, and related PFAS compounds

Gen-X is an emerging polyfluorinated alkyl substance, hexafluoroprolyene oxide (HFPO-DA), and it with other novel PFAS is shown as part of a multi-component PFAS acquisition method. Gen-X and several PFOS-replacement compounds were optimized on the SCIEX Triple Quad™ 4500 System.

Analysis of PFAS in drinking water with EPA method 537.1 and the SCIEX QTRAP 4500 system

In order to protect the safety of drinking water and human health, the EPA releases methods for the detection of contaminants. The EPA method 537.1 describes the detection of selected per- and polyfluorinated alkyl substances in drinking water. Here a robust LC-MRM assay was developed using the QTRAP 4500 system for PFAS detection. Sensitive MDLs of 0.08-0.2 ng/L for all of 14 PFAS compounds in EPA method 537 were achieved, all of which meet or exceed the requirements of the US EPA’s UCMR3 list in a 10 minute run.

Use of electron activated dissociation (EAD) to elucidate PFAS structures

Poly- and perfluoroalkyl substances (PFAS) are widely used and are now broadly detected in the environment. There are an estimated 5,000 unique PFAS manufactured making determination of the specific PFAS compound challenging. Structural assignment depends on obtaining high quality MS/MS spectra, but traditional collision-induced dissociation (CID) do not always yield enough information to provide definitive assignment. Here , electron activated dissociation (EAD) has been evaluated to determine whether this orthogonal fragmentation mode can improve qualitative PFAS structure elucidation.

GenX and legacy PFAS analysis in water and sediment with high selectivity and sensitivity

GenX is a replacement chemical for PFOA and increasingly high levels of GenX contamination in the environment near manufacturing plants is being reported. HRMS is important in monitoring these novel PFAS compounds in complex matrices due to the additional selectivity possible. Here, a targeted method for the detection of perfluoroalkyl ether carboxylic acids (PFECAs), including GenX (HFPO-DA) and shorter-chain analogues, in water and sediment samples was developed using the SCIEX X500 QTOF system. Low to mid parts-per-trillion detection limits with enhanced selectivity were obtained.

Analysis of PFAS at low ppt levels in drinking water via EPA method 533

Per- and polyfluorinated alkyl substances (PFAS) are a group of manmade chemicals that are known to enter the water supply and bioaccumulate in watershed ecosystems. Hence, the US EPA published the fifth unregulated contaminant monitoring rule (UCMR5)5, which proposes maximum residue limits (MRL) for PFAS residues in EPA method 533. A method has been developed here using solid phase extraction (SPE) and the SCIEX Triple Quad 4500 system monitoring 22 different PFAS species. Observed sensitivity and reproducibility meets the UCMR5 requirements for EPA method 533 compounds.

PFAS identification in serum and plasma using data-independent acquisition and MS/MS library matching

In this technical note, the SCIEX X500 QTOF system was used to analyze PFAS in human serum. An unbiased and non-targeted workflow with automatic library matching allowed for wider, comprehensive sample analysis. Additionally, a streamlined sample preparation strategy maintained sample integrity while providing greater laboratory efficiency.

EPA method 533 for PFAS analysis in drinking water at low parts-per-trillion levels

PFAS drinking water analysis by EPA Method 5331 using the SCIEX 5500+ System. Excellent sensitivity and precision were as shown; the “in-sample” minimum reporting limits were 2 ng/L for all analytes except PFHpA which was 4 ng/L. Novel perfluorinated ether carboxylic and sulfonic acids were detected in 0.50 ng/mL standard, which corresponds to 2 ng/L in sample, significantly below the US EPA drinking water guidelines of 70 ng/L for PFOS and PFOA. Custom built calculations and flagging rules in SCIEX OS Software streamlined data review and report generation.

Reducing PFAS interferences during human plasma and serum analysis with accurate mass spectrometry

Co-eluting interferences in biological matrices have been shown for PFOS and PFHxS when monitoring the [SO3]- fragment ion. Here, accurate mass spectrometry was used to mass resolve PFOS & PFHxS from these interferences. The separation used was able to chromatographically resolve the interferences using a 6.5 minute gradient. The interferences were then characterized using their MS/MS fragmentation spectra and library searching.

Low-level quantification of PFAS in water samples with high sensitivity and precision

Per- and polyfluoroalkyl substances (PFAS) have excellent stain repellent properties and are thus widely used in packaging materials, firefighting foams and many other uses. As PFAS have been found in virtually every environmental matrix including drinking water supplies, making monitoring critical to ensure safety. Here, a comprehensive quantitative method for a suite of PFAS compounds was developed for analysis of water samples on the SCIEX 7500 system. This high sensitivity system provided S/N gains of ~5.5x on average across the 54 compounds analyzed versus the SCIEX 6500+ system..

Reducing the effects of system contamination in PFAS analysis

Because of the pervasive nature of PFAS and the suggested PFAS detection limits continuingly being decreased in environmental sample analysis, there is an increasing need to have LC-MS strategies that can effectively manage PFAS background. Here, a workflow was established on the ExionLC 2.0 system with the optional wash system using delay columns to separate background PFAS contamination from sample analysis. An assay for 52 PFAS analytes was used to characterize the performance attributes of the LC system, including carryover. Analysis was performed using the SCIEX Triple Quad 7500 system to obtain very high sensitivity.

Achieving exceptional robustness for PFAS analysis in food with the next-generation SCIEX 7500+ system

This technical note demonstrates >2x robustness improvement for the analysis of PFAS food extracts on the SCIEX 7500+ system. At the end of the study, comprising over 6400 food matrix injections, the majority of PFAS compounds (10 out 13) maintained >70% of the initial sensitivity.