An advanced integrated GC-MS/MS and LC-MS/MS workflow for the comprehensive analysis of pesticide residues in food

Significance of the Topic

Modern agriculture relies on over a thousand different pesticides to protect crops and maintain yields. However, misuse or overuse can lead to contamination of the food supply and pose risks to consumer health. Regulatory bodies worldwide set Maximum Residue Levels (MRLs) and require routine monitoring to ensure food safety. Sensitive, robust, and efficient analytical workflows are essential for multi‐residue pesticide screening across diverse food matrices.

Study Objectives and Overview

This study evaluated a combined GC‐MS/MS and LC‐MS/MS workflow integrated into Thermo Scientific Chromeleon CDS software. Proficiency test (PT) samples of homogenized French green beans and wheat, each containing 10–25 unknown pesticides at 0.020–0.200 mg/kg from a list of approximately 250 compounds, were analyzed. The goal was to demonstrate improved laboratory productivity, data confidence, and compliance through automated cross‐confirmation and streamlined data review.

Methodology

The QuEChERS AOAC 2007.01 method was used for sample extraction. Green bean samples (15 g) were extracted with 15 mL acetonitrile; wheat samples (5 g) received 15 mL water followed by 15 mL acetonitrile. Extracts for LC‐MS/MS analysis were injected directly, while GC‐MS/MS extracts were cleaned using a QuEChERS clean‐up kit and solvent‐exchanged into heptane.

Instrumentation

• LC‐MS/MS workflow: Vanquish Flex UHPLC coupled to Altis Plus triple quadrupole MS, using a Hypersil GOLD C18 column (150 × 2.1 mm, 3 µm).
• GC‐MS/MS workflow: TRACE 1610 GC with TriPlus SMART autosampler and iConnect Thermospray injector, coupled to TSQ 9610 triple quadrupole with Advanced Electron Ionization source, using a TraceGOLD TG-SQC column (15 m × 0.25 mm, 0.25 µm).

Main Results and Discussion

Combined workflows enabled detection of up to 697 pesticides: 443 via GC‐MS/MS in a 20‐minute run and 593 via LC‐MS/MS in a 22‐minute run, with 49 % overlap. All quantified residues in both green bean and wheat PT samples fell within the expected concentration ranges; Z‐scores were predominantly below 1, classifying all results as satisfactory. The Chromeleon CDS cross‐confirmation interface facilitated rapid identity confirmation and accurate quantitation, even in complex matrices.

Benefits and Practical Applications

• Pre-configured “out-of-the-box” workflows reduce method development time and accelerate laboratory implementation.
• Centralized data processing in Chromeleon CDS minimizes training requirements and unifies review of GC and LC data.
• Automated filtering and customizable view settings focus analysts on exceptions, improving throughput and reducing error rates.
• Cross‐confirmation of LC and GC results increases confidence and reduces the need for repeat analyses, lowering cost per sample.

Future Trends and Applications

Future developments may include expansion to high‐resolution mass spectrometry for non‐targeted screening, incorporation of artificial intelligence for automated data validation, real‐time data sharing across networked instruments, and further miniaturization of sample preparation to increase throughput. Integration with laboratory information management systems will streamline reporting and regulatory compliance.

Conclusion

The integrated GC-MS/MS and LC-MS/MS workflow with Chromeleon CDS provides a robust, high-throughput solution for comprehensive multi-residue pesticide analysis. It delivers accurate, precise, and traceable results in complex food matrices while simplifying data review and improving laboratory efficiency.

References

1. World Health Organization. Pesticide residues in food. Fact Sheet. September 15, 2022.
2. European Commission Directorate General for Health and Safety. Guidance document on analytical quality control and method validation procedures for pesticide residues in food and feed. SANTE/11312/2021. January 1, 2022.
3. Chromeleon CDS – Pesticides Solution. Thermo Fisher Scientific.
4. BIPEA. Proficiency testing and reference materials. https://www.bipea.org/proficiency-testing/
5. BIPEA programs PTS 66b: Multi-residue screening of pesticides – Cereals; PTS 66c: Multi-residue screening of pesticides – Vegetables.