ISO 10695:2000

Overview

ISO 10695:2000 is an International Standard for water quality testing that specifies gas chromatographic methods for the determination of selected organic nitrogen and phosphorus compounds in waters. Published in 2000, it defines two validated sample-preparation routes - liquid/liquid extraction and liquid/solid extraction - and covers instrument requirements, calibration, identification, calculation and reporting. The standard includes informative annexes on detection limits, example chromatograms, MS ions and precision data.

Key SEO keywords: ISO 10695:2000, water quality standard, gas chromatographic methods, organic nitrogen and phosphorus, liquid-liquid extraction, liquid-solid extraction, nitrogen-phosphorus detector, GC-MS.

Key Topics

• Scope and analytes
  • Specifies gas chromatographic analysis for a number of pesticides and organophosphorus compounds (examples: atrazine, simazine, parathion, trifluralin, vinclozolin).
  • Methods can be extended to other substances after validation.
• Extraction methods
  • Liquid/liquid extraction: for drinking, ground, surface and waste waters (suitable for samples with up to ~0.05 g/L suspended solids); uses dichloromethane extraction and concentration prior to GC.
  • Liquid/solid extraction: intended for very low concentration samples (sub-μg/L range) using solid-phase material (e.g., RP-C18).
• Instrumentation and detection
  • Gas chromatograph with capillary columns (different polarities recommended) and a nitrogen–phosphorus detector (NPD); MS may be used for confirmation.
  • Annex B gives example chromatographic conditions.
• Reagents, calibration and QA
  • Purity requirements for solvents, preparation and storage of stock/intermediate/working standards, and blank checks.
  • Calibration guidance for external and internal standards; analytical quality control per ISO/TR 13530.
• Sampling and stability
  • Sampling guidance references ISO 5667 series; samples should be protected from light, stored cold, and extracted promptly due to potential rapid degradation.
• Safety
  • Explicit warning about use of flammable and toxic organic solvents and analytes; follow applicable safety regulations.

Applications and Users

• Environmental and public-health laboratories performing routine monitoring of drinking water, groundwater, surface water and wastewater.
• Regulatory agencies and compliance testing for pesticides and organophosphorus pollutants.
• Research groups validating new analytes by GC or GC–MS for trace organic nitrogen/phosphorus compounds.
• Water utilities and consultants conducting contamination assessments and source-tracking.

Related Standards

• ISO 5667-1 / ISO 5667-2 (sampling guidance)
• ISO/TR 13530 (analytical quality control for water analysis)

ISO 10695:2000 provides a practical, validated framework for trace analysis of organic N and P compounds by GC, supporting accurate monitoring and regulatory compliance in water quality programs.