Determination of 30 Per- and Polyfluoroalkyl Substances in Fruits, Vegetables, and Juices

Significance of the Topic

Determination of per- and polyfluoroalkyl substances (PFAS) in fruits, vegetables, and juices is essential due to increasing regulatory limits and potential health risks. Persistent and bioaccumulative, PFAS contamination in food has prompted recent European Commission regulations and AOAC SMPR guidelines, creating demand for reliable analytical workflows.

Objectives and Study Overview

This study aimed to develop and validate a simplified, high-throughput method for analyzing 30 PFAS in six representative matrices (grape, lettuce, mushroom, carrot, tomato, and orange juice). Key objectives included achieving regulatory limits of quantitation (LOQs), minimizing matrix effects, and ensuring accuracy and precision.

Methodology and Instrumentation

Sample preparation combined QuEChERS extraction with acetonitrile containing 1% acetic acid, followed by passthrough cleanup using Agilent Captiva EMR PFAS Food I cartridges. After evaporation and reconstitution, analytes were separated on a ZORBAX RRHD Eclipse Plus C18 column (2.1×100 mm, 1.8 µm) with a 5 mM ammonium acetate/methanol gradient. Detection employed an Agilent 6470B triple quadrupole LC/MS/MS in negative electrospray ionization with dynamic multiple reaction monitoring and neat standard calibration from 10–5,000 ng/L.

Used Instrumentation

• Agilent 1290 Infinity II LC system (high-speed pump, multisampler, multicolumn thermostat)
• Agilent 6470B LC/TQ mass spectrometer with PFC-free HPLC conversion kit
• Agilent Captiva EMR PFAS Food I cartridges (6 mL, 340 mg)
• Agilent Bond Elut QuEChERS EN extraction kit
• Thermo Centra CL3R centrifuge, Geno/Grinder, Heidolph tube shaker
• Agilent PPM-48 positive pressure manifold, CentriVap concentrator

Main Results and Discussion

EMR mixed-mode cleanup outperformed conventional dispersive SPE, delivering PFAS recoveries of 89–114% (RSD ≈5%) versus 47–105% (RSD ≈20%) for dSPE. Efficient pigment and lipid removal yielded >90% sample volume recovery, enabling low-ppt detection. Validated LOQs met AOAC SMPR requirements (≤0.01 µg/kg for core PFAS) in most matrices; elevated background in mushroom and carrot slightly raised LOQs for PFNA and PFOS. Calibration curves were linear (R2>0.99) over a 500× dynamic range. Accuracy (65–135% recovery) and repeatability (≤25% RSD) satisfied acceptance criteria.

Benefits and Practical Applications

• Rapid, simplified sample cleanup with minimal manual handling
• Robust matrix removal and consistent low-ppt quantitation
• No need for matrix-matched calibration curves
• High throughput suitable for routine QC and regulatory compliance

Future Trends and Potential Applications

Expansion to additional food and environmental matrices, integration with high-resolution mass spectrometry for non-target screening, and adoption of automated sample preparation platforms are anticipated. Advancements in instrument sensitivity (e.g., Agilent 6495D) will support even lower LOQs and evolving regulatory requirements.

Conclusion

The validated QuEChERS-EMR/LC-MS/MS workflow provides a sensitive, reliable, and efficient solution for multiresidue PFAS analysis in fruits, vegetables, and juices. Its strong performance in recovery, precision, and matrix clearance supports routine compliance testing under current regulatory guidelines.

References

1. Commission Regulation (EU) 2023/915 on maximum levels for PFOS, PFOA, PFNA, and PFHxS in food.
2. AOAC SMPR 2023.003 Standard Method Performance Requirements for 30 PFAS in produce, beverages, dairy, eggs, seafood, meat, and feed.
3. Genualdi S.; Young W.; Peprah E.; et al. Analyte and matrix method extension of PFAS in food and feed. Anal Bioanal Chem (2024).
4. Zhao L.; Giardina M.; Parry E. Determination of 30 PFAS in infant formula, milk, and eggs. Agilent Technologies Application Note, 5994-7366EN (2024).
5. Zhao L.; Giardina M.; Parry E. Determination of 30 PFAS in baby food. Agilent Technologies Application Note, 5994-7367EN (2024).