Determination of Pesticide Residues in Rice- Based Baby Food Using GC-MS/MS with APGC After Extraction and Clean Up Using QuEChERS

Significance of the Topic

Infant and young children are especially susceptible to pesticide exposure due to their higher intake of food relative to body weight, incomplete metabolic development, and restricted diet variety. Regulatory bodies in the EU have set stringent maximum residue levels (MRLs) for cereals and baby foods, frequently at or below 0.01 mg/kg and in some cases down to 0.003 mg/kg, to ensure consumer safety. Reliable, high‐throughput analytical methods are therefore essential to monitor compliance with these limits and to support risk assessment efforts.

Objectives and Study Overview

This study aimed to develop and validate a comprehensive multiresidue method for the determination of 166 gas‐chromatography‐amenable pesticides and their relevant degradants in rice‐based baby food. The approach combines a cereal‐adapted QuEChERS extraction with gas chromatography–tandem mass spectrometry (GC-MS/MS) using atmospheric pressure chemical ionization (APGC) on a Xevo TQ-XS platform. Validation followed SANTE/12682/2019 guidelines, focusing on sensitivity, specificity, recovery, repeatability, and linearity at concentrations relevant to regulatory limits and risk assessment.

Methodology and Instrumentation

The extraction protocol employs a modified QuEChERS procedure optimized for cereal matrices to isolate pesticide residues from rice‐based baby food. The analytical determination utilizes GC-MS/MS equipped with APGC, which enhances ionization efficiency and selectivity compared to traditional electron ionization. Key instruments and software included:

• Xevo TQ-XS triple quadrupole mass spectrometer with APGC source
• Conventional splitless GC injection (1 µL acetonitrile extract)
• MassLynx and TargetLynx for data acquisition and processing

Main Results and Discussion

The APGC-GC-MS/MS method achieved exceptional sensitivity, with limits of detection (LODs) of 0.0003 mg/kg for 165 out of 166 pesticides; thiometon exhibited an LOD of 0.0005 mg/kg. Reporting limits were set at 0.001 mg/kg to comply with blank evaluation criteria. Linear calibration curves (r2 > 0.98 for 95% of analytes) were established over the concentration range 0.0003–0.01 mg/kg. Recovery tests at two spike levels (0.0005 and 0.001 mg/kg) showed that 90–92% of analytes fell within the 70–120% recovery window, with repeatability (RSDr) ≤20% for over 96% of compounds. Ion ratio and retention time criteria were met for 94% of analytes.

Benefits and Practical Applications

• High sensitivity and specificity enable compliance monitoring for stringent infant food MRLs without requiring solvent change, large‐volume injection, or specialized injection techniques.
• The streamlined workflow supports high‐throughput laboratories in food safety testing, regulatory monitoring, and industry QA/QC.
• Capability to quantify residues at levels well below legal thresholds aids risk assessment and consumer protection efforts.

Future Trends and Opportunities

Advances in atmospheric pressure ionization and tandem mass spectrometry are expected to further improve sensitivity and reduce analysis time. Integration with automated sample preparation and data processing pipelines can enhance throughput. Emerging hybrid techniques, such as coupling with ion mobility spectrometry, may provide additional separation capabilities for complex matrices. Expanding the pesticide target list and adapting methods for other vulnerable foodstuffs will broaden the utility of APGC-GC-MS/MS in regulatory and research settings.

Conclusion

The developed APGC-GC-MS/MS method combined with QuEChERS extraction demonstrates high sensitivity, accuracy, and robustness for multiresidue analysis of 166 pesticides in rice‐based baby food. Validation results confirm its suitability for regulatory compliance testing and risk assessment, delivering reliable quantification at trace levels without elaborate sample handling.

References

1. Commission Directive 2006/125/EC on processed cereal‐based foods and baby foods for infants.
2. Commission Delegated Regulation (EU) 2021/1041 on pesticides in infant formula and follow‐on formula.
3. Cherta L. et al. J Chromatogr A. 2013;1314:224–240.
4. Waters Application Note 720007654. 2022.
5. EURL‐CF Validation Report 38. 2021.
6. SANTE/12682/2019 Guidance Document on pesticide residue analysis.