Elemental Analysis in Food for Risk Assessment and Provenance Studies

Importance of the Topic

This study addresses the critical need for comprehensive elemental profiling in food matrices to support safety assessments and authenticity verification. Trace and major element analysis are fundamental for monitoring contaminants such as lead, arsenic, cadmium and for ensuring nutritional quality. Furthermore, rare earth element signatures offer a novel route to trace food provenance and confirm labeling claims.

Study Objectives and Overview

The primary aim was to demonstrate the combined use of ICP‐OES and triple quadrupole ICP‐MS for accurate quantification of major and trace elements across diverse food samples. Certified reference materials representing diet, animal tissue and plant leaves were analyzed to evaluate sensitivity, precision and interference removal. The work highlights how axial and radial plasma views, collision/reaction cell strategies and automated dilution streamline workflows for food quality laboratories.

Methodology

Sample Preparation:

• Microwave digestion of 0.3–0.5 g of CRM in HNO₃/HCl mixture
• Final volumes: 50 mL for ICP‐OES, 10 mL for ICP‐MS

Analytical Approaches:

• ICP‐OES: Dual-view measurements (axial for sensitivity, radial for matrix tolerance)
• ICP‐MS: Triple quadrupole operation in SQ‐KED and TQ‐O₂ modes to eliminate spectral interferences
• Automated prescriptive dilution using an autodilution system for out-of-range samples

Used Instrumentation

• Thermo Scientific iCAP 7400 ICP‐OES Duo
• Thermo Scientific iCAP TQ ICP‐MS
• Elemental Scientific prepFAST Autodilution System
• Thermo Scientific Qtegra ISDS software with Reaction Finder Assistant

Main Results and Discussion

ICP‐OES results for major elements (Ca, Mg, Fe, P, Zn) showed recoveries within 96–103%, demonstrating robust performance across axial/radial views. The iCAP TQ ICP‐MS delivered interference‐free quantification of trace elements including As and Se by removing doubly charged rare earth ions using O₂ cell gas. Recoveries for trace analytes in apple and tomato leaf CRMs matched certified values within 90–110%. Rare earth element profiles (e.g., Nd, Gd, Ba) were clearly resolved in mass spectra, underscoring their utility for provenance studies.

Benefits and Practical Applications

This multi‐technique approach offers:

• High throughput analysis of 24 elements in a single sequence
• Automated dilution and method development reduce hands-on time
• Wide dynamic range covering major to ultratrace levels
• Reliable interference removal for food safety and QA/QC laboratories
• Capability to authenticate geographic origin via rare earth signatures

Future Trends and Opportunities

Advancements in hardware and software will drive:

• Integration of AI-guided method optimization for complex matrices
• Expanded non-targeted screening to capture emerging contaminants
• Miniaturization and portable ICP systems for field analysis
• Enhanced data analytics linking elemental fingerprints to supply chain verification

Conclusion

The combination of ICP‐OES and triple quadrupole ICP‐MS, supported by automated dilution and intelligent software, provides a versatile, interference‐free platform for food elemental analysis. This workflow meets regulatory requirements for accuracy and precision, while enabling provenance verification through rare earth profiling.

References

• Application Note 43446: Total elemental analysis of food samples using Thermo Scientific iCAP TQ ICP-MS with autodilution
• Application Note 40755: Robust single method determination of major and trace elements in foodstuffs using Thermo Scientific iCAP 7400 ICP-OES Duo