Overview
ISO 14182:1999 specifies a gas chromatographic method for the determination of residues of selected organophosphorus pesticides in animal feeding stuffs. The method is intended for routine pesticide residue analysis in feed matrices and defines sample preparation, extraction, cleanup, chromatographic determination and reporting. It is validated for a defined list of pesticides (e.g., chlorpyrifos, parathion, malathion, diazinon, azinphos‑methyl, pirimiphos‑methyl, etc.) with a lower limit of determination of 0.01 µg/g. The standard also includes informative annexes with example GC operating conditions and interlaboratory results.
Key topics and technical requirements
- Scope & applicability: Method applies to the enumerated organophosphorus pesticides; may be applicable to other OPs but not validated for them.
- Sampling / sample prep: Follow ISO 6498 for preparation of test samples (grinding, homogenizing). Typical test portions: 50 g for dry/low‑moisture feeds, 100 g for high‑moisture feeds.
- Extraction: Test portion is extracted with acetone, diluted with water and saturated NaCl, then partitioned into dichloromethane.
- Cleanup: Concentrated extract purified on a chromatographic column packed with 10% water‑deactivated silica gel; elution solvent recommended is 50% dichloromethane in hexane.
- Chromatography & detection: Gas chromatograph with splitless or on‑column injection and either a phosphorus‑selective detector (FPD or NPD in P mode) or a mass‑selective detector (MSD). Detector sensitivity requirement: minimum detection limit of 50 pg of phosphorus compounds. Capillary columns (nonpolar to mid‑polarity) and temperature programming are recommended.
- Standards & calibration: Uses an internal standard (tributylphosphate). Stock/intermediate/working solution preparation and storage stability guidance are given (e.g., 1 000 µg/ml stock). Linearity of the system is checked using parathion (0.1 ng to 2 ng; inject 2 µl).
- Documentation: Procedures for expression of results, identity confirmation, precision and test reporting are included.
Applications and users
ISO 14182:1999 is used by:
- Accredited pesticide residue laboratories and feed testing labs
- Regulatory agencies performing surveillance of animal feed safety
- Feed manufacturers and quality‑control teams verifying compliance with residue limits
- Contract analytical service providers and research groups studying pesticide contamination in feeds
The method supports regulatory compliance, quality assurance, and risk‑based monitoring of organophosphorus residues in animal feeding stuffs.
Related standards
- ISO 6498 - Preparation of test samples (referenced for sample prep)
- ISO 3696 - Water for analytical laboratory use (referenced for reagent quality)
Keywords: ISO 14182:1999, organophosphorus pesticides, gas chromatographic method, animal feeding stuffs, pesticide residue analysis, phosphorus‑selective detector, mass‑selective detector, silica gel cleanup, acetone extraction.