Confident analysis of ultra-trace pesticides residues in baby food using triple quadrupole GC-MS

Importance of the Topic

Ensuring the safety of baby food requires analytical methods capable of detecting ultra-trace levels of pesticide residues. Regulatory bodies in the EU set maximum residue limits (MRLs) as low as 3–8 µg/kg for certain banned compounds in infant products. Laboratories must therefore adopt highly sensitive, selective, and robust workflows to protect consumer health and comply with stringent standards.

Objectives and Study Overview

This study aimed to evaluate the performance of the Thermo Scientific™ TSQ™ 9610 triple quadrupole GC-MS system, coupled to a TRACE™ 1610 GC with programmable temperature vaporizing injector and AI/AS 1610 autosampler, for multi-residue analysis of over 200 pesticides in baby food matrices. Key figures of merit—linearity, sensitivity, recovery, precision, and long-term robustness—were assessed in spiked QuEChERS extracts.

Sample Preparation and Methodology

Baby food samples (2–15 g) were extracted by a citrate-buffered QuEChERS protocol using 10–15 mL acetonitrile, followed by dispersive SPE cleanup. This procedure requires minimal equipment, solvent, and bench space, offers rapid shaking‐only homogenization, and yields clean extracts suitable for GC-MS/MS.

Instrumental Setup

• GC-MS System: Thermo Scientific TSQ 9610 triple quadrupole with NeverVent™ AEI ion source and XLXR™ detector.
• Gas Chromatograph: TRACE 1610 GC equipped with iConnect™ programmable temperature vaporizing (PTV) injector and TraceGOLD™ TG-5SilMS column (30 m × 0.25 mm × 0.25 µm).
• Autosampler: AI/AS 1610 liquid autosampler in fast splitless mode.
• Ionization and Acquisition: Electron ionization (EI), timed-SRM (t-SRM) of quantifier and qualifier transitions per SANTE guidelines.
• Software: Chromeleon™ 7.3 CDS for automated control, acquisition, processing, and compliance checking.

Main Results and Discussion

• Linearity: Matrix-matched calibration from 0.05 to 500 µg/kg yielded R² > 0.99 and AvCF RSD < 15%.
• Detection Limits: Instrument detection limits ranged from 0.006 to 0.65 µg/kg (6–650 fg on column), average 0.073 µg/kg.
• Recovery and Precision: Spiking at 3 µg/kg produced recoveries of 70–120% with RSD ≤ 10%.
• Robustness: Over 500 randomized injections of various baby food matrices at 10 µg/kg, normalized peak areas and ion ratios remained stable. NeverVent AEI allowed ion source cleaning in under two hours without breaking vacuum, ensuring minimal downtime.

Benefits and Practical Applications

The described workflow delivers high sensitivity and selectivity for multi-class pesticide residue screening in baby food. Its fast throughput, low solvent use, reliable performance, and automated compliance checks make it ideal for routine QA/QC laboratories under strict regulatory regimes.

Future Trends and Opportunities

Emerging developments include integration of high-resolution accurate mass detection, advanced data analytics with AI-driven flagging, miniaturized sample preparation for greener workflows, and further automation to increase throughput while reducing maintenance.

Conclusion

The TSQ 9610 GC-MS/MS platform combined with QuEChERS extraction and TRACE 1610 GC demonstrated excellent analytical performance for ultra-trace pesticide residues in baby food. The method meets EU SANTE criteria for sensitivity, accuracy, and robustness, supporting reliable food safety monitoring.

References

1. Fussell R. J. White Paper: Regulation and control of pesticide residues in food, Thermo Fisher Scientific, 2016.
2. European Commission. Guidelines on Maximum Residue Levels, EC website.
3. Directive 2006/125/EC on processed cereal-based foods and baby foods, EU Official Journal.
4. Payá P. et al. Analysis of pesticide residues using QuEChERS with GC- and LC-MS/MS. Anal Bioanal Chem. 2007;389:1697–1714.
5. SANTE/12682/2019. Guidance on analytical quality control and method validation for pesticide residues in food and feed.
6. Thermo Fisher Scientific. NeverVent Advanced Electron Ionization and TRACE 1610 GC Application Notes.