Use of Non-Target Analysis for Matrix Mitigation and Accurate Quantification of Legacy PFAS

Advances in High Resolution Mass Spectrometry and Its Emerging Environmental Applications
Oral Presentation

Prepared by C. Neslund
Eurofins Lancaster Laboratories Environment Testing, 2425 New Holland Pike, Lancaster, PA, 17601, United States


Contact Information: [email protected]; 717-556-7231


ABSTRACT

For the majority of analytical applications for the analysis of PFAS in environmental samples, LC/MS/MS is the workhorse used for detection and quantification. For PFAS, the LC/MS/MS application was introduced in applications with drinking water. Most of these applications used single ion transitions because of the vintage of mass spec and the complexity (or lack there of) of the matrix. However, as investigations into PFAS analysis have extended into complex matrices the use of a triple quad has been challenged.

We have tried to adjust to those challenges by adding and improving clean-ups of extracts. We have also added secondary transition ions and ratio matching to help insure the certainty of the identification and quantification in complex matrices. However, LC/MS/MS still has some limitations in the unit mass resolution afforded by that technology.

We will present examples of where complex matrices presented results for legacy PFAS that were unexpectedly high. We used the power of qTOF to determine that within the complex matrices there were coeluting compounds that resulted in falsely high results for legacy PFAS. The qTOF enabled the detection of transition masses that were not characteristic of the legacy PFAS and not resolvable by the triple quad and allowed for the more accurate quantification of the legacy PFAS.