Determination of pesticides and persistent organic pollutants in honey by accelerated solvent extraction and GC-MS/MS

Significance of the Topic

This work addresses the critical need to monitor trace-level pesticides and persistent organic pollutants (POPs) in honey. As consumers demand high-quality, contaminant-free natural products and regulators enforce strict residue limits, robust analytical methods are essential to ensure food safety, verify organic labeling, and protect public health.

Objectives and Study Overview

The primary goal was to develop and validate a rapid, solvent-efficient method combining accelerated solvent extraction (ASE) with inline cleanup and tandem mass spectrometry for simultaneous analysis of four pollutant classes in honey. Sixty-eight compounds—including six PCBs, seven PBDEs, 16 organochlorine pesticides, 19 organophosphorus pesticides and 11 additional agrochemicals—were targeted. Fifty-nine organic honey samples from three Italian regions (Calabria, Trentino Alto Adige, Lombardia) were analyzed to assess regional contamination patterns.

Methodology

Samples (2 g honey) were mixed with dispersant and packed into 34 mL ASE cells containing Florisil and cellulose filters for cleanup. Extraction used hexane/ethyl acetate (4:1) at 80 °C and 1500 psi with three static cycles. Extracts were dried, reconstituted, and injected into a GC-MS/MS system. Quantitation employed matrix-matched calibration, internal standards, and selected reaction monitoring to achieve low ng/g detection limits.

Used Instrumentation

• Thermo Scientific Dionex ASE 350 Accelerated Solvent Extractor
• Thermo Scientific Rocket Evaporator for solvent reduction
• Thermo Scientific TRACE 1310 Gas Chromatograph with PTV inlet
• Thermo Scientific TSQ 8000 Evo Triple Quadrupole GC-MS/MS
• Xcalibur and TraceFinder software for data processing

Main Results and Discussion

• Method performance: Recoveries 75–105%, RSD ≤14%, linearity (r²≥0.995), LODs 0.01–1.26 ng/g depending on compound.
• PCBs were found in all samples (0.27–0.92 ng/g), with no significant regional differences.
• PBDEs were below detection, likely reflecting organic production zones.
• Organochlorine pesticides persisted: endrin and aldrin detected in all regions, DDT and metabolites up to 2 ng/g, endosulfan sulfate up to 5.4 ng/g—below EU MRLs.
• Organophosphorus pesticide residues were most prevalent in samples from the apple-growing Trentino Alto Adige, with diazinon, mevinphos and others at 0.7–1.2 ng/g; captan and coumaphos were frequent in Lombardia and Calabria.

Benefits and Practical Applications

This ASE-GC-MS/MS approach streamlines cleanup and extraction into a single step, reducing solvent consumption, analysis time, and instrument maintenance. It meets stringent regulatory requirements for multiresidue monitoring in honey and can be adapted to various food matrices and contaminant panels.

Future Trends and Opportunities

Advances may include integration of high-resolution mass spectrometry for non-target screening, miniaturized extraction platforms for on-site testing, and automated workflows linked to laboratory information systems. Expanding the scope to emerging contaminants and adapting the method for rapid screening in field laboratories will enhance food safety surveillance.

Conclusion

The developed ASE inline-cleanup method coupled with GC-MS/MS delivers reliable, sensitive, and high-throughput analysis of pesticides and POPs in honey. It supports regulatory compliance, protects consumer health, and offers a template for monitoring complex contaminants in diverse food products.

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