Overview
ISO 15302:2017 specifies a validated analytical method for the determination of benzo[a]pyrene in crude or refined edible animal and vegetable fats and oils. The method uses reverse‑phase high performance liquid chromatography (HPLC) with fluorimetric detection and covers the working range 0.1 µg/kg to 50 µg/kg. Milk and milk products (and fats derived from them) are explicitly excluded from this standard. The document describes sample preparation, cleanup, chromatographic conditions, calibration and calculation of results.
Key topics and technical requirements
- Scope and matrix: Applicable to crude and refined edible oils and fats; milk/milk products excluded.
- Sensitivity: Quantitative range 0.1–50 µg/kg for benzo[a]pyrene.
- Sample preparation & cleanup:
- Test portion dissolved in light petroleum (or hexane) and spiked with benzo[b]chrysene as internal standard.
- Adsorption on deactivated alumina packed column; sodium sulfate layer used for drying.
- Elution with light petroleum, concentration by evaporation and nitrogen drying, residue reconstituted for HPLC injection.
- Chromatography:
- Reverse‑phase HPLC with a PAH‑capable column (typical 250 × 4.6 mm) and guard/precolumn.
- Mobile phase: acetonitrile–water (880 ml : 120 ml) degassed; flow ≈ 1 ml/min.
- Fluorescence detector: excitation 384 nm, emission 406 nm (slits 10 nm).
- Injection volumes and sample loading limits specified to avoid overloading (e.g., ≤1.5 mg residue on column).
- Calibration and quantification:
- Five‑point calibration using benzo[a]pyrene standards (range down to 0.01 ng injected) with internal standard to determine relative response factors.
- Safety and quality:
- Benzo[a]pyrene is a known carcinogen-work in a fume hood with appropriate PPE.
- Use HPLC‑grade solvents; perform blank analyses if non‑recommended solvents are used.
- Precision & reporting: Procedures for repeatability, reproducibility and required test report elements are included.
Applications and users
ISO 15302:2017 is intended for:
- Food testing and quality control laboratories monitoring polycyclic aromatic hydrocarbons (PAHs) in edible oils and fats.
- Regulatory and enforcement bodies requiring standardized, traceable methods for benzo[a]pyrene surveillance.
- Oil and fat manufacturers performing product safety testing and supplier validation.
- Research groups studying contamination, processing effects or environmental transfer of PAHs into food matrices.
Typical applications include contamination screening, compliance testing, import/export verification and process control to reduce PAH exposure.
Related standards
- ISO 661 - Preparation of test sample (referenced for sample prep).
- ISO 5555 - Recommended sampling methods (sampling itself is outside ISO 15302’s method).
- Developed by ISO/TC 34, Subcommittee SC 11 (Animal and vegetable fats and oils).
Keywords: ISO 15302:2017, benzo[a]pyrene, HPLC, reverse‑phase, fluorimetric detection, edible oils, fats, PAHs, analytical method, food safety.