Multiresidue pesticides analysis in Curcumin color additive powder using GCMS-TQ8040 NX and LCMS-8050

Significance of the Topic

The high use of pesticides in turmeric cultivation raises concerns about residual contaminants in curcumin color additive powder used in food and cosmetics. Monitoring these residues is essential to ensure consumer safety and regulatory compliance.

Objectives and Study Overview

This study aimed to validate a multi-residue analytical method for detecting over 70 pesticides in curcumin powder by combining a modified QuEChERS extraction with GC-MS/MS and LC-MS/MS techniques. It focused on assessing linearity, recovery, repeatability and within-laboratory reproducibility at trace levels.

Methodology

A single extraction workflow based on a modified QuEChERS protocol was applied to matrix-matched curcumin powder. The procedure included:

• Extraction with acetonitrile and an optimized salt mixture (NaCl, MgSO4, trisodium citrate dihydrate, disodium hydrogen citrate sesquihydrate)
• Cleanup using C18, graphitized carbon black, primary secondary amine, zirconium and MgSO4 to reduce matrix interference
• Division of the extract: reconstitution in ethyl acetate for GC-MS/MS and dilution with methanol plus filtration for LC-MS/MS

Applied Instrumentation

• GC-MS/MS: Shimadzu GCMS-TQ8040 NX equipped with AOC-20i+s auto-injector and SH-Rxi-5Sil MS column
• LC-MS/MS: Shimadzu LCMS-8050 with Nexera X2 front end and Shim-pack Scepter column
• Method optimization supported by Shimadzu Smart Pesticides Database Ver.2 (GC-MS/MS) and Method Package Ver.3 (LC-MS/MS)
• Data processing via LabSolutions Insight software

Main Results and Discussion

The validated method demonstrated:

• Limits of quantification of 5 µg/kg for 61 pesticides; some compounds showed LOQs of 10 µg/kg or 20 µg/kg depending on instrumental performance
• Recoveries between 60 and 120% at LOQ levels, meeting SMPR criteria
• Repeatability (RSDr) below 20% and reproducibility (RSDR) below 30% for most analytes
• Excellent linearity with correlation coefficients (R²) typically above 0.99
• Suppression of matrix effects through optimized cleanup, enabling sensitive detection in a complex matrix

Benefits and Practical Applications

• Comprehensive screening for a wide range of pesticide residues in complex matrices
• High throughput facilitated by rapid QuEChERS extraction and fast instrument cycles
• Flexible choice between GC-MS/MS and LC-MS/MS based on LOQ and compound properties
• Applicability to quality control in food, cosmetic and pharmaceutical industries

Future Trends and Potential Uses

• Integration with high-resolution mass spectrometry for non-targeted screening
• Automation of sample preparation and data analysis workflows
• Expansion of compound databases for emerging pesticides and transformation products
• Miniaturization and field-deployable systems for on-site monitoring

Conclusion

The study confirms that a modified QuEChERS protocol combined with GC-MS/MS and LC-MS/MS provides a robust, sensitive and reproducible platform for multi-residue pesticide analysis in curcumin powder. The method meets stringent validation criteria and supports effective risk assessment and regulatory compliance.

Reference

1. M Anastassiades, SJ Lehotay, D Štajnbaher, FJ Schenck, Fast and Easy Multiresidue Method Employing Acetonitrile Extraction/Partitioning and Dispersive Solid-Phase Extraction for the Determination of Pesticide Residues in Produce, J AOAC Int, 86 (2003) 412–431
2. Guidance Document on Analytical Quality Control and Method Validation Procedures for Pesticide Residues Analysis in Food and Feed SANTE/12682/2019