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

Rapid, low-level analysis using the SCIEX 7500 system

Craig Butt


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.

12617 7500


Per- and polyfluoroalkyl substances (PFAS) are synthetic chemical compounds with properties that have excellent resistance to heat, water, oil and grease. PFAS are widely used in food and other product packaging materials, as water and stain repellents, in firefighting foams and within many industrial processes.1 There is now ample evidence that exposure to high levels of PFAS can lead to adverse health outcomes in humans.2 Because PFAS bio-accumulate, the risk is even more profound.

Studies over the last two decades have shown that PFAS can be found in virtually every environmental matrix. Many municipal drinking water supplies within the US and around the world contain PFAS contamination. As a result, the EU has set regulations for acceptable levels of PFAS.3 While the US Environmental Protection Agency (EPA) is still establishing maximum contaminant levels (MCLs) for PFAS, it has issued health advisories. To better evaluate the risks of PFAS to human health, it is important to monitor their levels within humans, water supplies and the environment.

In this technical note, the SCIEX 7500 system was evaluated for the quantification of a comprehensive suite of PFAS compounds in a sample of surface water. This system was designed to enable new levels of sensitivity for the quantification of previously undetectable compounds. Results from the SCIEX 7500 system were compared with results from the SCIEX Triple Quad 6500+ system, an established platform that is routinely used for low-level quantification of PFAS compounds. Figure 1 shows the comparison of a representative PFAS compound, perfluorohexanesulfonic acid (PFHxS).

Figure 1. MRM peaks for perfluorohexanesulfonic acid (PFHxS). The SCIEX 7500 system data (right) shows a 7.1x increase in S/N compared with the SCIEX Triple Quad 6500+ system data (left). Note: gray shaded areas represent the noise region used for the S/N calculation.

Key features of the SCIEX 7500 system for PFAS quantification

  • A fast, 10-min method for quantification of PFAS provides rapid analysis with even greater sensitivity than previous platforms.
  • Greater signal-to-noise (S/N) leads to the ability to quantify PFAS compounds even at trace levels.
  • Excellent precision with CV of less than 10% across multiple replicate injections means higher confidence in quantified levels.
  • Intuitive and user-friendly, SCIEX OS software automatically detects, quantifies, flags outliers and reports results to ease the manual workload and speed up final answers.