PFAS Quantitation from Food Contact Materials Using the Agilent 6495D Triple Quadrupole LC/MS System

Significance of the Topic

Per- and polyfluoroalkyl substances PFAS are extensively used in food contact materials to impart resistance to grease and moisture but can migrate into food raising health and environmental concerns. Sensitive and reliable analytical methods are essential to ensure compliance with evolving regulations and to protect consumer safety.

Study Objectives and Overview

This study develops and validates an analytical workflow for quantifying 110 PFAS, including 73 native and 37 labeled compounds, in paper straw samples. The method aims for low microgram per kilogram detection limits, strong linearity, and robust accuracy and precision in complex matrices.

Methodology and Instrumentation

A paper straw sample was cut into small pieces and a 1 gram aliquot was placed in a polypropylene tube. After spiking with native and surrogate PFAS standards, 10 milliliters of methanol were added and samples were mixed on a mechanical shaker at 2000 rpm for 30 minutes followed by ultrasonic assisted extraction at 60 degrees Celsius for one hour. This extraction cycle was repeated twice. Samples were centrifuged, filtered through PFAS-free nylon syringe filters, and diluted with water and isotope performance standards prior to LC TQ analysis.
Instrumentation included an Agilent 1290 Infinity II UHPLC equipped with a dedicated PFAS-free flow path kit and a ZORBAX RRHD Eclipse Plus C18 column using a gradient of ammonium acetate in water and methanol at 0.4 milliliters per minute. Detection was performed on an Agilent 6495D triple quadrupole mass spectrometer with a Jet Stream electrospray source in negative mode. Data acquisition used a validated multiple reaction monitoring MRM database covering over 100 PFAS targets.

Main Results and Discussion

The method achieved method detection limits MDLs below 0.2 micrograms per kilogram for all 73 native analytes, with 20 compounds exhibiting MDLs below 0.05 micrograms per kilogram. Key regulated PFAS such as PFOA, PFOS, PFNA, PFDA and PFHxS showed MDLs under 0.1 micrograms per kilogram. Linearity was excellent across calibration ranges with correlation coefficients above 0.99 for most targets. Limit of quantification LOQ was 1 microgram per kilogram for 89 percent of analytes. Recovery in matrix spiked quality controls ranged from 65 to 120 percent for 90 percent of targets and precision was within 20 percent relative standard deviation. Procedural blanks showed no contamination and matrix blanks indicated trace PFAS background. Overlay of MRM traces for critical analytes confirmed reproducible retention times and signal responses.

Benefits and Practical Applications

• High sensitivity and reliability for ppt-level PFAS quantitation
• Simple dilute-and-shoot protocol minimizes sample preparation
• Comprehensive coverage of native and labeled PFAS targets
• Suitable for routine screening and regulatory compliance
• Effective removal of background contamination with PFAS-free consumables

Future Trends and Opportunities

Expansion of target lists to include emerging PFAS and transformation products, implementation of non-targeted high resolution mass spectrometry, development of standardized interlaboratory studies, automation of extraction workflows, and application to a broader range of packaging materials and food matrices.

Conclusion

The described LC TQ workflow provides a rapid, sensitive, and robust approach for PFAS quantitation in food contact materials demonstrating low detection limits, excellent linearity, and reliable accuracy and precision. Adoption of PFAS-free instrumentation consumables ensures trustworthy results supporting regulatory monitoring and risk management.

References

1. U S Environmental Protection Agency PFAS Explained
2. National Institute of Environmental Health Sciences Perfluoroalkyl and Polyfluoroalkyl Substances PFAS
3. Consumer Reports Dangerous PFAS Chemicals Are in Your Food Packaging
4. OECD PFASs and Alternatives in Food Packaging
5. Commission Regulation EU No 10 2011 on Plastic Materials
6. European Chemicals Agency Annex XV Restriction Report Proposal for a Restriction of PFAS
7. Per and Polyfluoroalkyl Substances Analysis for Environmental Samples Agilent Technologies
8. Method Development and Screening of Extractable Organofluorine and PFAS in Packaging Materials
9. Wells G Prest H William Russ C Signal Noise and Detection Limits in Mass Spectrometry Agilent Technologies
10. US EPA Definition and Procedure for the Determination of the Method Detection Limit Revision 2
11. AOAC International Standard Method Performance Requirements for PFAS in Food and Feed
12. US Environmental Protection Agency Method 1633 Analysis of PFAS by LC MS MS
13. US Food and Drug Administration Determination of PFAS in Food and Feed by LC MS MS