This article, featured in issue 16 of the Analytix Reporter, presents a study on the extraction and analysis of 16 per- and polyfluoroalkyl substances (PFAS) from ultra-high temperature (UHT) processed milk. Employing the FDA's method C-010.02, the research utilizes a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction, enhanced by a subsequent dispersive solid phase extraction (dSPE) for cleanup. The precise quantification of PFAS is accomplished through LC-MS/MS analysis, with protocols designed to mitigate PFAS contamination in food samples.
This study demonstrates an effective method for detecting trace PFAS in milk, achieving recovery rates within FDA guidelines. The use of specific clean-up tubes, extraction salts, columns, and filters effectively supports sensitive PFAS analysis, underscoring their suitability for contaminant testing in food samples.
INTRODUCTION
Due to their chemical stability and widespread use in various products, PFAS pose potential bioaccumulation risks in humans. Regulatory agencies such as the U.S. Food and Drug Administration (FDA) and Environmental Protection Agency (EPA) have introduced limited values and analytical methods for PFAS testing to mitigate health impacts, including cancer and immune system effects.
The FDA's C-010.02 method for analyzing PFAS in food involves a modified QuEChERS extraction and a dSPE clean-up, followed by LC-MS/MS analysis. This method specifies using a mix of 6.0 g MgSO4 and 1.5 g NaCl for extraction, and a clean-up mix of 900 mg MgSO4, 300 mg PSA, and 150 mg graphitized carbon. To comply with these requirements, the Supel™ QuE non-buffered extraction salt mix and the specifically developed Supel™ QuE PSA/ENVI-Carb™ Tube 3 are utilized.
This application describes the analysis of 16 PFAS compounds in milk and was performed in accordance with FDA method C-010.02.
EXPERIMENTAL PROCEDURE
See the full article for details on:
- Solutions and standards preparation
- Sample preparation
- Evaluation of background contamination
- Method performance assessment
- LC-MS/MS analysis
RESULTS & DISCUSSION
All 16 compounds demonstrated a lower limit of quantitation (LLOQ) of 0.01 ng/mL for the HPLC method and an LLOQ of 0.02 ng/mL in the context of the milk sample. Linear calibration curves (0.01-25 ng/mL) with R2 ≥0.99 were obtained for all PFAS analytes.
Read the full article for comprehensive results and discussion.
CONCLUSION
In this application note, the workflow for FDA method C-010.02 to analyze 16 PFAS in processed food using the QuEChERS method was investigated for milk samples. The background values of all used consumables and the LC-MS system resulted in levels below the LLOQs given in the method. Recovery rates for the investigated compounds at both tested concentrations fell within the FDA's recommended range, with relative standard deviations under 11%, demonstrating the method's accuracy and precision. The study confirms the effectiveness and usability of the Supel™ QuE PSA/ENVI-Carb clean-up Tube 3, the non-buffered extraction salt mix, the Ascentis® Express PFAS columns (analytical & delay), and Millex® syringe filters for PFAS analysis in milk samples.