Ethylene Oxide & 2-Chloroethanol analysis in Foods using Triple Quadrupole GC/MS/MS

Significance of the Topic

Ethylene oxide (EO) fumigation is widely employed in the spice and seed industry to control microbial contaminants while preserving delicate matrices. However, EO reacts to form 2-chloroethanol (2-CE), raising food safety and regulatory concerns. Recent recalls of products such as sesame seeds and locust bean gum–containing foods have driven demand for reliable residue analysis methods.

Objectives and Study Overview

This work reviews multiple GC-MS/MS approaches for quantifying EO and 2-CE in dry food commodities. It compares the established EU Reference Lab single-residue method, a streamlined EO-to-2-CE conversion protocol, and the Korean MFDS procedure. Key goals include demonstrating regulatory compliance, improving throughput, and validating performance in sesame seeds.

Methodology and Instrumentation

Sample preparation strategies include acidified aqueous extraction, salt addition, sonication, and liquid–liquid extraction with ethyl acetate, followed by QuEChERS clean-up.

• GC columns: HP-VOC, VF-624 ms, DB-WAX UI (lengths 30–60 m, internal diameters 0.20–0.25 mm).
• Injection: split or pulsed splitless (2 μL), temperature programs tailored for volatile (EO) and polar (2-CE) analytes.
• MS detection: Agilent triple quadrupole systems (7890B/7010B, 8890/7000D) in EI mode with MRM transitions for EO, 2-CE and deuterated internal standards.

Results and Discussion

The EU-SRM method achieved low-ng/g LOQs for both analytes with clear chromatographic separation. The simplified EO-to-2-CE conversion workflow delivered LOQs of 10 ng/g, recoveries of 82–101 %, and signal-to-noise ratios >14 at regulatory thresholds. The Korean MFDS method provided comparable sensitivity using a wax column and validated MRM settings.

Benefits and Practical Applications

These validated protocols enable laboratories to:

• Monitor EO and 2-CE residues against EU MRLs (0.02–0.1 mg/kg) and U.S. EPA guidelines.
• Adapt workflows to different commodity matrices with minimal lipid interference.
• Leverage deuterated standards and MRM for robust quantitation in regulatory testing.

Future Trends and Potential Applications

Advances may include automated sample preparation, high-throughput GC-MS/MS platforms, and alternative markers such as 2-bromoethanol. Integration of data analytics and cross-lab standardization will further streamline compliance testing across global supply chains.

Conclusion

Robust GC-MS/MS methods offer sensitive, accurate quantitation of EO and 2-CE in foods. Streamlined workflows maintain regulatory compliance while reducing analysis time, supporting quality control and safety monitoring in spice, seed, and processed food industries.

Reference

1. Multi-country recalls due to ethylene oxide in sesame seeds. Food Safety News, 2020.
2. EPA ethylene oxide assessment, EPA.gov.
3. ATSDR toxicological profile for ethylene oxide, CDC.gov.
4. EU Implementing Regulation 2020/1540.
5. EU food recalls over ethylene oxide concerns, Food Quality & Safety.
6. German single-residue method EN-15662.
7. EURL-Pesticides EO SRM observation, 2017.
8. Control procedures for EO contamination in sesame seeds for export to EU.
9. Korean MFDS test method for EO and 2-CE in food.
10. Agilent application note 5994-3805EN: EO and 2-CE in sesame seeds using 8890 GC/7000D TQ.